Risk Factors for Urinary Tract Infections in Renal Allograft Recipients: Experience of a Tertiary Care Center in Hyderabad, South India.

PubMed

Mohan, M V N L R; Neeraja, M; Sudhaharan, S; Raju, S B; Gangadhar, T; Lakshmi, V

2017-01-01

Renal transplantation is an effective and commonly performed procedure for end-stage renal disease. Urinary tract infections are a major cause of morbidity and mortality in renal transplant patients. As data on postrenal transplant urinary tract infections from the Indian subcontinent are limited, the present study was conducted to estimate the burden of urinary tract infections in this vulnerable group of patients. This was a prospective study on patients undergoing renal transplantation in 2014 at our tertiary hospital in South India with a follow-up of 2 years to evaluate the risk factors for urinary tract infections. The prevalence of urinary tract infections was 41.9% with a male preponderance of 76.9%. Mean age of the 31 patients was 32.4 ± 10.2 years (range: 16-55 years). Gram-negative bacilli were the most common isolates with Escherichia coli being the predominant pathogen (53.3%). All the infections occurred within 1 year of transplantation with delayed graft function ( P < 0.001; confidence interval [CI]: 29.0-96.3) and prolonged hospital stay ( P = 0.0281; CI: 42.1-99.6) being the significant risk factors for acquiring urinary tract infections. Carbapenemase production was noted in 33.3% of isolates and all the Gram-negative organisms isolated in the 1 st month of transplantation were carbapenem-resistant (CR) E. coli . The high rate of carbapenem-resistant organisms in the early posttransplant period is a point of concern, especially with cadaver transplants. Infection control practices and catheter care need to be strictly monitored to minimize the risk for UTI in the immediate posttransplant period.

Evaluation of the in vitro activity of levornidazole, its metabolites and comparators against clinical anaerobic bacteria.

PubMed

Hu, Jiali; Zhang, Jing; Wu, Shi; Zhu, Demei; Huang, Haihui; Chen, Yuancheng; Yang, Yang; Zhang, Yingyuan

2014-12-01

This study evaluated the in vitro anti-anaerobic activity and spectrum of levornidazole, its metabolites and comparators against 375 clinical isolates of anaerobic bacteria, including Gram-negative bacilli (181 strains), Gram-negative cocci (11 strains), Gram-positive bacilli (139 strains) and Gram-positive cocci (44 strains), covering 34 species. Minimum inhibitory concentrations (MICs) of levornidazole, its five metabolites and three comparators against these anaerobic isolates were determined by the agar dilution method. Minimum bactericidal concentrations (MBCs) of levornidazole and metronidazole were measured against 22 strains of Bacteroides fragilis. Levornidazole showed good activity against B. fragilis, other Bacteroides spp., Clostridium difficile, Clostridium perfringens and Peptostreptococcus magnus, evidenced by MIC90 values of 0.5, 1, 0.25, 2 and 1mg/L, respectively. The activity of levornidazole and the comparators was poor for Veillonella spp. Generally, levornidazole displayed activity similar to or slightly higher than that of metronidazole, ornidazole and dextrornidazole against anaerobic Gram-negative bacilli, Gram-positive bacilli and Gram-positive cocci, especially B. fragilis. Favourable anti-anaerobic activity was also seen with levornidazole metabolites M1 and M4 but not M2, M3 or M5. For the 22 clinical B. fragilis strains, MBC50 and MBC90 values of levornidazole were 2mg/L and 4mg/L, respectively. Both MBC50/MIC50 and MBC90/MIC90 ratios of levornidazole were 4, similar to those of metronidazole. Levornidazole is an important anti-anaerobic option in clinical settings in terms of its potent and broad-spectrum in vitro activity, bactericidal property, and the anti-anaerobic activity of its metabolites M1 and M4. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Risk factors associated with fluoroquinolone-resistant enterococcal urinary tract infections in a tertiary care university hospital in north India.

PubMed

Banerjee, Tuhina; Anupurba, Shampa

2016-10-01

Fluoroquinolone resistance in both Gram-positive and Gram-negative bacteria has increased with the widespread use of fluoroquinolones. Fluoroquinolone resistance in Gram-negative bacilli has been widely studied, though staphylococci and enterococci are also notably resistant. Enterococci being the second most common cause of healthcare-associated urinary tract infections (UTIs) fluoroquinolones are often the drug of choice. This study was undertaken to assess the risk factors associated with fluoroquinolone-resistant enterococcal UTI in a tertiary level health facility in north India. A total of 365 patients with UTI caused by enterococci were studied over a period of two years. Patients with ciprofloxacin-resistant and susceptible UTI were considered as cases and controls, respectively. Resistance profile of the isolates against common antibiotics was studied by minimum inhibitory concentration (MIC) determination. Mechanisms for fluoroquinolone resistance was studied by efflux pump inhibitor activity and multiplex PCR targeting the qnr genes. A total of 204 (55.89%) cases and 161 (44.1%) controls were identified. The fluoroquinolone-resistant isolates were significantly resistant to ampicillin, high strength aminoglycosides and vancomycin. The majority (78%) of the resistant isolates showed efflux pump activity. Treatment in indoor locations, presence of urinary catheters and pregnancy along with recent exposure to antibiotics especially fluoroquinolones, third generation cephalosporins and piperacillin-tazobactam were identified as independent risk factors. Our results showed that fluoroquinolone resistance in enterococcal UTI was largely associated with indoor usage of antibiotics and use of indwelling devices. Knowledge of risk factors is important to curb this emergence of resistance.

In Vitro Activity of Delafloxacin against Contemporary Bacterial Pathogens from the United States and Europe, 2014

PubMed Central

Pfaller, M. A.; Sader, H. S.; Rhomberg, P. R.

2017-01-01

ABSTRACT The in vitro activities of delafloxacin and comparator antimicrobial agents against 6,485 bacterial isolates collected from medical centers in Europe and the United States in 2014 were tested. Delafloxacin was the most potent agent tested against methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus, Streptococcus pneumoniae, viridans group streptococci, and beta-hemolytic streptococci and had activity similar to that of ciprofloxacin and levofloxacin against certain members of the Enterobacteriaceae. Overall, the broadest coverage of the tested pathogens (Gram-positive cocci and Gram-negative bacilli) was observed with meropenem and tigecycline in both Europe and the United States. Delafloxacin was shown to be active against organisms that may be encountered in acute bacterial skin and skin structure infections, respiratory infections, and urinary tract infections. PMID:28167542

In Vitro Activity of Delafloxacin against Contemporary Bacterial Pathogens from the United States and Europe, 2014.

PubMed

Pfaller, M A; Sader, H S; Rhomberg, P R; Flamm, R K

2017-04-01

The in vitro activities of delafloxacin and comparator antimicrobial agents against 6,485 bacterial isolates collected from medical centers in Europe and the United States in 2014 were tested. Delafloxacin was the most potent agent tested against methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus , Streptococcus pneumoniae , viridans group streptococci, and beta-hemolytic streptococci and had activity similar to that of ciprofloxacin and levofloxacin against certain members of the Enterobacteriaceae Overall, the broadest coverage of the tested pathogens (Gram-positive cocci and Gram-negative bacilli) was observed with meropenem and tigecycline in both Europe and the United States. Delafloxacin was shown to be active against organisms that may be encountered in acute bacterial skin and skin structure infections, respiratory infections, and urinary tract infections. Copyright © 2017 Pfaller et al.

Isolation, identification and sensitivity pattern of microorganisms isolated from the urine of pregnant women.

PubMed

Karim, S; Khan, K I

1994-01-01

The present studies were conducted to detect and identify the microorganism from the urine of pregnant women having urinary tract infection. The antibiotic susceptibility of these isolated microorganisms was also determined. The microorganisms found responsible for the infection were bacteria, fungi, yeast and protozoa. Among the bacteria two were identified as Gram-positive cocci i.e. Staphylococcus aureus and S. epidermidis, the remaining two were Gram-negative bacilli which were Escherichia coil and Pseudomonas aeruginosa. The fungus was identified as AspelEillus niger and the yeast like fungus Candida albican. The only protozoan found in some of the urine samples was Trichomonas vaginalis. These isolated and identified microorganisms were more susceptible to Norfloxacin, Velosef, Minocin, Nitrofurantoin, Malidixic acid and Metronidazole whereas antibiotics Penbritin and Cefaloridine were least effective against these microorganisms.

Long-term outcome of acute prosthetic joint infections due to gram-negative bacilli treated with retention of prosthesis.

PubMed

Jaén, N; Martínez-Pastor, J C; Muñoz-Mahamud, E; García-Ramiro, S; Bosch, J; Mensa, J; Soriano, A

2012-09-01

To update the clinical information of the 47 patients with a prosthetic joint infection due to Gram-negative bacilli included in a previous study and to reassess the predictors of failure after a longer follow-up. Using the electronic files of our hospital, all the information regarding readmissions to the hospital, new surgical procedures and the reason for the new surgery (infection, aseptic loosening), and the last visit in the hospital were registered. The medical chart of the 35 patients that were considered in remission in the previous publication was reviewed. In 30 patients no clinical evidence of failure was detected and no additional surgery on the previously infected prosthesis was necessary and they were considered in long-term remission. In 5 cases a late complication was identified. One case had a reinfection due to coagulase-negative staphylococci after 22 months from the open debridement and required a 2-stage revision surgery. The other 4 cases developed an aseptic loosening and it was necessary to perform a 1-stage exchange. Receiving a fluoroquinolone when all the Gram-negatives involved in the infection were susceptible to fluoroquinolones was the only factor associated with remission in the univariate analysis (p=0.002). After a long-term follow-up, our results support the importance of using fluoroquinolones in acute PJI due to Gram-negative bacilli.

Microbiology of Drycleaning

PubMed Central

Banville, Robert R.; McNeil, Ethel

1966-01-01

An appreciable number of bacteria on contaminated fabric survived modern drycleaning procedures. Various stages in the process, especially steam pressing, reduced the total number of bacteria, but viable organisms were found on certain areas of garments even after pressing. A significant number of bacteria were redeposited on clean fabric during the washing of ordinary soiled garments in drycleaning units. These bacteria included gram-positive cocci, diphtheroid bacilli, and gram-positive sporeformers. Gram-negative bacilli were seldom found, although some gram-negative bacilli survived drycleaning. The redeposited organisms apparently came mainly from other garments in the same loads, as few bacteria were isolated from the filtered solvent used for washing. The number of bacteria in the drycleaning washwheel was highest shortly after the beginning of the wash, and decreased, with the exchange of solvent in the wheel, to a low level at the end. Although it appears that in most cases several factors combine to reduce to a low level the numbers of bacteria on articles cleaned in a well-operated drycleaning plant, it would seem that under certain conditions pathogenic microorganisms could be disseminated by drycleaning. Images Fig. 2 PMID:4958148

In Vitro Activities of Y-688, a New 7-Substituted Fluoroquinolone, against Anaerobic Bacteria

PubMed Central

MacGowan, A. P.; Bowker, K. E.; Wootton, M.; Holt, H. A.; Reeves, D. S.

1998-01-01

The in vitro activities of Y-688, a new 7-substituted fluoroquinolone derivative, against 317 nonduplicate anaerobic isolates were determined. Eighty-five percent of the Bacteroides fragilis group (n = 89) were inhibited by ≤2 mg of Y-688 per liter, while 78, 100, 89, and 98% of gram-negative bacilli (n = 135), gram-positive cocci (n = 59), and non-spore-forming (n = 58) and spore-forming (n = 51) gram-positive bacilli, respectively, were inhibited by ≤1 mg of Y-688 per liter. PMID:9527797

[Urinary tract infections and their prevention].

PubMed

González-Chamorro, F; Palacios, R; Alcover, J; Campos, J; Borrego, F; Dámaso, D

2012-01-01

This article reviews diverse aspects of the prevention of urinary tract infections, including confirmation of the diagnosis, application of hygiene and dietary measures, antibacterial prophylaxis (preferably consisting of a single nocturnal oral dose per day of an antibiotic or drug with high urinary excretion and good tolerance), and administration of vaccines made with Escherichia coli and other Gram-negative bacilli, consisting of immunostimulating fractions of E. coli strains or E. coli type-1 fimbriae administered through the parenteral or oral route. We aimed to review the new preventive measures against urinary tract infections. ACQUISITION AND SYNTHESIS OF EVIDENCE: We reviewed various microbiological aspects, as well as the physiopathology and virulence factors of uropathogenic E. coli strains expressing type-1 and P fimbriae. The association between blood groups and urinary tract infections in blood group antigen-secretors and nonsecretors was analyzed. New preventive measures against urinary tract infection consist of the use of phenol-inactivated vaccines administered via the mucosal route, inhibitors of bacterial adherence and biofilm formation and cyclic adenosine monophosphate stimulators, especially in women aged between puberty and menopause, who show the highest incidence of these infections. Copyright © 2011 AEU. Published by Elsevier Espana. All rights reserved.

Infective endocarditis due to Enterobacter cloacae resistant to third- and fourth-generation cephalosporins.

PubMed

Yoshino, Yusuke; Okugawa, Shu; Kimura, Satoshi; Makita, Eiko; Seo, Kazunori; Koga, Ichiro; Matsunaga, Naohisa; Kitazawa, Takatoshi; Ota, Yasuo

2015-04-01

We report the case of using a long-term combination of meropenem and amikacin to treat infective endocarditis caused by Enterobacter cloacae resistant to third- and fourth-generation cephalosporins. Multi-drug resistant Gram-negative bacilli, such as the E. cloacae in our study, may become possible pathogens of infective endocarditis. Our experience with this case indicates that long-term use of a combination of β-lactam and aminoglycosides might represent a suitable management option for future infective endocarditis cases due to non-Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella spp. (HACEK group) Gram-negative bacilli such as ours. Copyright © 2012. Published by Elsevier B.V.

Appropriateness of gram-negative agent use at a tertiary care hospital in the setting of significant antimicrobial resistance.

PubMed

Vora, Neil M; Kubin, Christine J; Furuya, E Yoko

2015-01-01

Background.  Practicing antimicrobial stewardship in the setting of widespread antimicrobial resistance among gram-negative bacilli, particularly in urban areas, is challenging. Methods.  We conducted a retrospective cross-sectional study at a tertiary care hospital with an established antimicrobial stewardship program in New York, New York to determine appropriateness of use of gram-negative antimicrobials and to identify factors associated with suboptimal antimicrobial use. Adult inpatients who received gram-negative agents on 2 dates, 1 June 2010 or 1 December 2010, were identified through pharmacy records. Clinical data were collected for each patient. Use of gram-negative agents was deemed optimal or suboptimal through chart review and according to hospital guidelines. Data were compared using χ(2) or Fischer's exact test for categorical variables and Student t test or Mann-Whitney U test for continuous variables. Results.  A total of 356 patients were included who received 422 gram-negative agents. Administration was deemed suboptimal in 26% of instances, with the most common reason being spectrum of activity too broad. In multivariable analysis, being in an intensive care unit (adjusted odds ratio [aOR], .49; 95% confidence interval [CI], .29-.84), having an infectious diseases consultation within the previous 7 days (aOR, .52; 95% CI, .28-.98), and having a history of multidrug-resistant gram-negative bacilli within the past year (aOR, .24; 95% CI, .09-.65) were associated with optimal gram-negative agent use. Beta-lactam/beta-lactamase inhibitor combination drug use (aOR, 2.6; 95% CI, 1.35-5.16) was associated with suboptimal use. Conclusions.  Gram-negative agents were used too broadly despite numerous antimicrobial stewardship program activities.

A molecular gram stain using broad range PCR and pyrosequencing technology: a potentially useful tool for diagnosing orthopaedic infections.

PubMed

Kobayashi, Naomi; Bauer, Thomas W; Togawa, Daisuke; Lieberman, Isador H; Sakai, Hiroshige; Fujishiro, Takaaki; Tuohy, Marion J; Procop, Gary W

2005-06-01

The bacteria associated with orthopaedic infections are usually common gram-positive and gram-negative bacteria. This fundamental grouping of bacteria is a necessary first step in the selection of appropriate antibiotics. Since polymerase chain reaction (PCR) is more rapid and may be more sensitive than culture, we developed a postamplification pyrosequencing method to subcategorize bacteria based on a few nucleotide polymorphisms in the 16S rRNA gene. We validated this method using well-characterized strains of bacteria and applied it to specimens from spinal surgery cases with suspected infections. Lysates of 114 bacteria including 75 species were created following standard cultivation to obtain DNA. The DNA was amplified by a broad-range real-time PCR. The amplicons were evaluated by pyrosequencing and were classified as gram-positive, gram-negative, or acid-fast bacilli based on the first three to five nucleotides sequenced. In addition, clinical cases of suspected infection were obtained from spinal surgery. The results of the "molecular Gram stain" were compared with the results of traditional Gram stain and culture. The lysates of 107 (93.9%) of the bacteria extracts tested were appropriately categorized as gram-positive and gram-negative or as acid-fast bacilli on the basis of this assay. The sensitivity and specificity of this assay were 100% and 97.4% for gram-positive and 88.3% and 100% for gram-negative isolates. All of the five clinical samples were appropriately categorized as containing gram-positive or gram-negative bacteria with this assay. This study demonstrates that high sensitivity and specificity of a molecular gram stain may be achieved using broad-range real-time PCR and pyrosequencing.

Invasive bacterial infections in a pediatric oncology unit in a tertiary care center.

PubMed

Trehan, A; Totadri, S; Gautam, V; Bansal, D; Ray, P

2014-01-01

Multidrug resistant (MDR) pathogens are becoming a major problem worldwide, more so in the immunocompromised hosts resulting in the urgent need of antibiotic stewardship. To analyze the organisms isolated and the drug resistance pattern in a pediatric oncology unit. Data pertaining to infections with 128 positive cultures in patients with febrile neutropenia over a period of 1-year are presented. The unit antibiotic policy is decided depending on the sensitivity of the prevailing common organisms. We isolated Gram-negative organisms in 56% cases. Escherichia coli and Klebseilla were the most frequent lactose fermenting Gram-negative Bacilli and Pseudomonas and Acinetobacter the nonfermenting Gram-negative Bacilli. Only 20-30% of the Gram-negative organisms cultured were sensitive to a 3rd/4th generation cephalosporin. The combination of a beta-lactam/inhibitor covered 2/3rd of Gram-negative organisms. About 80% of the organisms were sensitive to carbapenems. There was no colistin resistance. About 44% of our cultures grew a Gram-positive bacterial organism and included coagulase negative Staphylococcus. We had an incidence of methicillin resistant Staphylococcus aureus to be 30%. About 30% of the enterococci isolated in our unit were vancomycin-resistant enterococci. About 23% of patients with a positive bacterial culture died. Infections in pediatric cancer patient's account for about 15-20% of the deaths in developing countries as these patients are at a high risk for developing MDR infections. Resistance rates among Gram-positive and Gram-negative organisms have increased worldwide. Every unit needs a rational antibiotic policy. Antibiotic de-escalation and judicious decrease in the duration of antibiotics needs to be practiced.

Clinical evaluation of the Vitek ANI card for identification of anaerobic bacteria.

PubMed Central

Schreckenberger, P C; Celig, D M; Janda, W M

1988-01-01

An evaluation of the Vitek Anaerobe Identification (ANI) card was performed with 341 bacterial isolates, including 313 clinical isolates and 28 stock strains of anaerobic microorganisms. Identifications obtained with the ANI card were compared with those determined by conventional methods. The card identified 73.2% of 149 anaerobic gram-negative bacilli, 63.6% of 44 Clostridium spp., 65.8% of 38 anaerobic nonsporeforming gram-positive bacilli, and 69.1% of 110 anaerobic cocci, with no further testing required. When genus-level identifications were included, 83.9% of the anaerobic gram-negative bacilli, 70.5% of Clostridium spp., 73.7% of the anaerobic nonsporeforming gram-positive bacilli, and 73.6% of the anaerobic cocci were identified. Nineteen isolates (5.6%) produced identifications of good confidence but marginal separation or questionable biotype, in which the correct identification was listed with one or two other possible choices and extra tests were required and suggested. A total of 28 (8.2%) were not identified and 29 isolates (8.5%) were misidentified by the ANI card. Among the commonly isolated clinically significant anaerobes, the ANI card identified 100% of 55 Bacteroides fragilis and 100% of 8 Clostridium perfringens. Use of supplemental tests and expansion of the data base to include additional strains of organisms that are difficult to separate even with conventional methods may improve the accuracy of the ANI card as a method for identification of anaerobic bacteria in the clinical laboratory. PMID:3343321

Antibiotic-Resistant Gram Negative Bacilli in Meals Delivered at a General Hospital, Italy

PubMed Central

Plano, Maria Rosa Anna; Di Noto, Anna Maria; Firenze, Alberto; Sciortino, Sonia; Mammina, Caterina

2009-01-01

This study aimed at detecting the presence of antibiotic-resistant Gram-negatives in samples of meals delivered at the University General Hospital of Palermo, Italy. Antibiotic resistant Gram negatives were isolated in July—September 2007 ffrom cold dishes and food contact surfaces and utensils. Bacterial strains were submitted to susceptibility test and subtyped by random amplification of polymorphic DNA (RAPD). Forty-six of 55 (83.6%) food samples and 14 of 17 (82.3%) environmental swabs were culture positive for Gram negative bacilli resistant to at least one group of antibacterial drugs. A total of 134 antibiotic resistant strains, 51 fermenters and 83 non-fermenters, were recovered. Fermenters and non-fermenters showed frequencies as high as 97.8% of resistance to two or more groups of antibiotics and non fermenters were 28.9% resistant to more than three groups. Molecular typing detected 34 different profiles among the fermenters and 68 among the non-fermenters. Antibiotic resistance was very common among both fermenters and non-fermenters. However, the wide heterogeneity of RAPD patterns seems to support a prominent role of cross-contamination rather than a clonal expansion of a few resistant isolates. A contribution of commensal Gram negatives colonizing foods to a common bacterial resistance pool should not been overlooked. PMID:19750189

Antibiotic-resistant gram negative bacilli in meals delivered at a general hospital, Italy.

PubMed

Plano, Maria Rosa Anna; Di Noto, Anna Maria; Firenze, Alberto; Sciortino, Sonia; Mammina, Caterina

2009-01-01

This study aimed at detecting the presence of antibiotic-resistant Gram-negatives in samples of meals delivered at the University General Hospital of Palermo, Italy. Antibiotic resistant Gram negatives were isolated in July-September 2007 ffrom cold dishes and food contact surfaces and utensils. Bacterial strains were submitted to susceptibility test and subtyped by random amplification of polymorphic DNA (RAPD). Forty-six of 55 (83.6%) food samples and 14 of 17 (82.3%) environmental swabs were culture positive for Gram negative bacilli resistant to at least one group of antibacterial drugs. A total of 134 antibiotic resistant strains, 51 fermenters and 83 non-fermenters, were recovered. Fermenters and non-fermenters showed frequencies as high as 97.8% of resistance to two or more groups of antibiotics and non fermenters were 28.9% resistant to more than three groups. Molecular typing detected 34 different profiles among the fermenters and 68 among the non-fermenters. Antibiotic resistance was very common among both fermenters and non-fermenters. However, the wide heterogeneity of RAPD patterns seems to support a prominent role of cross-contamination rather than a clonal expansion of a few resistant isolates. A contribution of commensal Gram negatives colonizing foods to a common bacterial resistance pool should not been overlooked.

Impact of fluoroquinolone administration on the emergence of fluoroquinolone-resistant gram-negative bacilli from gastrointestinal flora.

PubMed

Richard, P; Delangle, M H; Raffi, F; Espaze, E; Richet, H

2001-01-01

We assessed the risk factors for acquisition of fluoroquinolone-resistant, gram-negative organisms in the gastrointestinal tract of hospitalized patients. We analyzed stool samples from 204 patients and recovered fluoroquinolone-resistant, gram-negative organisms from 63. Receipt of fluoroquinolone during the month preceding admission was the only risk factor identified, whereas female sex, duration of hospitalization, exposure to indwelling devices, admission from another hospital, and history of infection were risk factors for fecal colonization after day 4.

Identification and susceptibility testing of microorganism by direct inoculation from positive blood culture bottles by combining MALDI-TOF and Vitek-2 Compact is rapid and effective.

PubMed

Romero-Gómez, María-Pilar; Gómez-Gil, Rosa; Paño-Pardo, Jose Ramón; Mingorance, Jesús

2012-12-01

The objective of this study was to evaluate the reliability and accuracy of the combined use of MALDI-TOF MS bacterial identification and the Vitek-2 Compact antimicrobial susceptibility testing (AST) directly from positive blood cultures. Direct identification by MALDI-TOF MS and AST were performed in parallel to the standard methods in all positively flagged blood cultures bottles during the study period. Three hundred and twenty four monomicrobial positive blood cultures were included in the present study, with 257 Gram-negative and 67 Gram-positive isolates. MALDI-TOF MS identification directly from blood bottles reported the correct identification for Enterobacteriaceae in 97.7%, non-fermentative Gram-negative bacilli 75.0%, Staphylococcus aureus 75.8%, coagulase negative staphylococci 63.3% and enterococci 63.3%. A total 6156 isolate/antimicrobial agent combinations were tested. Enterobacteriaceae group and non-fermentative Gram-negative Bacilli showed an agreement of 96.67% and 92.30%, respectively, for the Gram-positive cocci the overall agreement found was 97.84%. We conclude that direct identification by MALDI-TOF and inoculation of Vitek-2 Compact AST with positive blood culture bottles yielded very good results and decreased time between initial inoculation of blood culture media and determination of the antibiotic susceptibility for Gram-negative rods and Gram-positive cocci causing bacteremia. Copyright © 2012 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

[Complicated urinary tract infections--from the perspective of the medical technologist].

PubMed

Nagasawa, Zenzo

2002-07-01

We would like to propose re-establishment of the protocol for ordering a clinical microbiology laboratory test after a bedside screening test using urine reagent strip when urinary tract infection is suspected. Media for isolation shall be chosen by the clinical microbiology laboratory after checking turbidity and microscopic examination of the urine specimen. In cases of complicated urinary tract infections, quantitative culture should be performed to investigate changes in the number of microorganism to grasp condition of super infection. In such infections, there are many cases in which multiple microorganism growth including glucose non-fermenting gram-negative bacilli can be recognized. Therefore, it is necessary to inspect colonies on media as long as possible (24 hrs culture may be short in some cases). The protocol for microorganism identification and susceptibility test for such specimen varies in each laboratory, considering the Health Insurance Point System (reimbursement system by MHW). It is necessary to communicate with physicians and to refer to past results to proceed with the laboratory test properly. Therefore, a Certified Clinical Microbiology Medical Technologist is needed and the role played by such staff is important.

Effectiveness of hand washing and disinfection methods in removing transient bacteria after patient nursing.

PubMed Central

Ojajärvi, J.

1980-01-01

The effectiveness of various hand washing and disinfection methods in removing transient skin bacteria was studied in hospital after dry or moist contamination of the hands when nursing burn patients. The results were compared with those of laboratory tests with volunteers. A fairly good correlation of the bacterial reductions existed between hospital and laboratory tests. All other methods removed Staph. aureus from the hands more effectively than liquid soap. Gram-negative bacilli were more easily removed than staphylococci, even with soap wash alone. In hospital, none of the washing and disinfection methods always removed all patient-borne bacteria from the hands. After dry or moist contamination and subsequent washing with soap only, colonies of Staph. aureus were often detected in finger-print samples. Staphylococci were more often completely removed by a 4% chlorhexidine detergent scrub and alcoholic solutions (either with or without previous soap wash) than by liquid soap, hexachlorophene or iodophor preparations. Gram-negative bacilli were more easily removed by all the washing and disinfection methods. After moist contamination, Gram-negative bacilli were more often completely removed from the hands by ethanol than by other treatments. The results of the present study emphasize the importance of always using gloves when nursing a profuse spreader of bacteria or one who must be protected from infection. PMID:6778914

[Left-sided endocarditis due to gram-negative bacilli: epidemiology and clinical characteristics].

PubMed

Noureddine, Mariam; de la Torre, Javier; Ivanova, Radka; Martínez, Francisco José; Lomas, Jose María; Plata, Antonio; Gálvez, Juan; Reguera, Jose María; Ruiz, Josefa; Hidalgo, Carmen; Luque, Rafael; García-López, María Victoria; de Alarcón, Arístides

2011-04-01

The aim of this study is to describe the epidemiological, clinical characteristics, and outcome of patients with left-side endocarditis caused by gram-negative bacteria. Prospective multicenter study of left-sided infective endocarditis reported in the Andalusian Cohort for the Study of Cardiovascular Infections between 1984 and 2008. Among the 961 endocarditis, 24 (2.5%) were caused by gram-negative bacilli. The most common pathogens were Escherichia coli, Pseudomonas aeruginosa and Salmonella enterica. Native valves (85.7%) were mainly affected, most of them with previous valve damage (57%). Comorbidity was greater (90% vs 39%; P=.05) than in endocarditis due to other microorganism, the most frequent being, diabetes, hepatic cirrhosis and neoplasm. A previous manipulation was found in 47.6% of the cases, and 37% were considered hospital-acquired. Renal failure (41%), central nervous system involvement (33%) and ventricular dysfunction (45%) were the most frequent complications. Five cases (21%) required cardiac surgery, mostly due to ventricular dysfunction. More than 50% of cases were treated with aminoglycosides, but this did not lead to a better outcome or prognosis. Mortality (10 patients) was higher than that reported with other microorganisms (41% vs 35%; P=.05). Left-sided endocarditis due to gram-negative bacilli is a rare disease, which affects patients with major morbidities and often with a previous history of hospital manipulations. Cardiac, neurological and renal complications are frequent and associated with a high mortality. The association of aminoglycosides in the antimicrobial treatment did not involve a better outcome or prognosis. Copyright © 2010 Elsevier España, S.L. All rights reserved.

[Periodontal microbiota and microorganisms isolated from heart valves in patients undergoing valve replacement surgery in a clinic in Cali, Colombia].

PubMed

Moreno, Sandra; Parra, Beatriz; Botero, Javier E; Moreno, Freddy; Vásquez, Daniel; Fernández, Hugo; Alba, Sandra; Gallego, Sara; Castillo, Gilberto; Contreras, Adolfo

2017-12-01

Periodontitis is an infectious disease that affects the support tissue of the teeth and it is associated with different systemic diseases, including cardiovascular disease. Microbiological studies facilitate the detection of microorganisms from subgingival and cardiovascular samples. To describe the cultivable periodontal microbiota and the presence of microorganisms in heart valves from patients undergoing valve replacement surgery in a clinic in Cali. We analyzed 30 subgingival and valvular tissue samples by means of two-phase culture medium, supplemented blood agar and trypticase soy agar with antibiotics. Conventional PCR was performed on samples of valve tissue. The periodontal pathogens isolated from periodontal pockets were: Fusobacterium nucleatum (50%), Prevotella intermedia/ nigrescens (40%), Campylobacter rectus (40%), Eikenella corrodens (36.7%), Gram negative enteric bacilli (36.7%), Porphyromonas gingivalis (33.3%), and Eubacterium spp. (33.3%). The pathogens isolated from the aortic valve were Propionibacterium acnes (12%), Gram negative enteric bacilli (8%), Bacteroides merdae (4%), and Clostridium bifermentans (4%), and from the mitral valve we isolated P. acnes and Clostridium beijerinckii. Conventional PCR did not return positive results for oral pathogens and bacterial DNA was detected only in two samples. Periodontal microbiota of patients undergoing surgery for heart valve replacement consisted of species of Gram-negative bacteria that have been associated with infections in extraoral tissues. However, there is no evidence of the presence of periodontal pathogens in valve tissue, because even though there were valve and subgingival samples positive for Gram-negative enteric bacilli, it is not possible to maintain they corresponded to the same phylogenetic origin.

Quantifying Glosair™ 400 efficacy for surface disinfection of American Type Culture Collection strains and micro-organisms recently isolated from intensive care unit patients.

PubMed

Herruzo, R; Vizcaíno, M J; Herruzo, I

2014-07-01

Microbial contamination of hospital surfaces may be a source of infection for hospitalized patients. We evaluated the efficacy of Glosair™ 400 against two American Type Culture Collection strains and 18 clinical isolates, placed on glass germ-carriers. Carriers were left to air-dry for 60 min and then exposed to a cycle before detection of any surviving micro-organisms. Antibiotic-susceptible Gram-negative bacilli were less susceptible (although not significantly) to this technique than resistant Gram-negative bacilli or Gram-positive cocci and yeasts (3, 3.4 and 4.6 log10 reduction, respectively). In conclusion, in areas that had not been cleaned, aerosolized hydrogen peroxide obtained >3 log10 mean destruction of patients' micro-organisms. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

[Anaerobic Gram-negative bacilli involved in the etiopathogeny of the abscesses of superficial fascial spaces of the face and neck].

PubMed

Băncescu, Gabriela; Băncescu, A; Dumitriu, Silvia; Skaug, N

2008-01-01

The aim of this study was to isolate and identify at species level the strains of anaerobic Gram-negative bacilli (GNB) from pus samples collected in patients with abscesses of fascial spaces of the face and neck. Microscopy of Gram-stained smears and cultures were performed in each specimen. The strictly anaerobic GNB strains were identified using the conventional methods of diagnosis and the Rapid ID 32 A system. In addition, the other strains isolated in association with these bacteria were identified at least to genus level. The 28 anaerobic GNB isolates belonged to: Fusobacterium nucleatum and different species of Prevotella (4 species) and Bacteroides (3 species). The anaerobic GBN strains were recovered--either alone or in association with other migroorganisms--in more than half of all investigated samples and represented about 40% of all isolates. The most frequently isolated species were P> melaninogenica and B. ureolyticus.

[Placental transfer and pharmacokinetic parameters of flomoxef during the perinatal period].

PubMed

Makinoda, S; Tsuruta, H; Iwaki, M; Negishi, H; Hanatani, K; Tanaka, T; Fujimoto, S

1991-06-01

Flomoxef (FMOX), a new oxacephem with low MIC values against not only Gram-negative bacilli (GNB) but also against Gram-positive cocci (GPC), was evaluated for its transfer into fetus, amniotic fluid, maternal milk, spinal fluid and urine during the perinatal period following a single intravenous drip infusion at a dose of 1 g for 30 minutes. The results obtained are summarized below. 1. High concentrations of FMOX were demonstrated in maternal serum, umbilical arterial serum and amniotic fluid with Cmax values of 48.0, 10.99 and 10.20 micrograms/ml, respectively. 2. Maternal urinary excretion rate was 65.4% in the first 6 hours after administration. 3. In contrast, maternal milk and spinal fluid levels were lower than 3 and 0.20 micrograms/ml, respectively. These results showed a good placental transfer of FMOX, which is very useful for various perinatal infections. No adverse effects were observed in mothers and neonates during the course of this study.

[Identification of anaerobic gram-negative bacilli isolated from various clinical specimens and determination of antibiotic resistance profiles with E-test methods].

PubMed

Demir, Cengiz; Keşli, Recep

2018-01-01

The aim of this study was to identify gram-negative anaerobic bacilli isolated from various clinical specimens that were obtained from patients with suspected anaerobic infections and to determine the antibiotic resistance profiles by using the antibiotic concentration gradient method. The study was performed in Afyon Kocatepe University Ahmet Necdet Sezer Research and Practice Hospital, Medical Microbiology Laboratory between 1 November 2014 and 30 October 2015. Two hundred and seventyeight clinical specimens accepted for anaerobic culture were enrolled in the study. All the samples were cultivated anaerobically by using Schaedler agar with 5% defibrinated sheep blood and Schaedler broth. The isolated anaerobic gram-negative bacilli were identified by using both the conventional methods and automated identification system (VITEK 2, bioMerieux, France). Antibiotic susceptibility tests were performed with antibiotic concentration gradient method (E-test, bioMerieux, France); against penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem for each isolate. Of the 28 isolated anaerobic gram-negative bacilli; 14 were identified as Bacteroides fragilis group, 9 were Prevotella spp., and 5 were Fusobacterium spp. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. No resistance was found against metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem. As a result, isolation and identification of anaerobic bacteria are difficult, time-consuming and more expensive when compared with the cost of aerobic culture. The rate of anaerobic bacteria isolation may be increased by obtaining the appropriate clinical specimen and appropriate transportation of these specimens. We believe that the data obtained from the study in our center may offer benefits for the follow up and treatment of infections caused by anaerobic bacteria and may contribute to the current literature. Because of high resistance rate detected against penicillin, this antibiotic should not be used as a first choice in empirical treatment. Cefoxitin may be used in empirical antimicrobial treatment of anaerobic gram-negatives; but the rate of antibiotic resistance should be detected for more useful and proper treatment. The prior selection of the most effective antibiotic, may contribute to decrease the rate of high resistance. In our study, no resistance was observed against carbapenem group antibiotics and metronidazole; so these antibiotics should be reserved as treatment options in the future for infections caused by resistant gram-negative anaerobic bacteria.

Ceftolozane/tazobactam: a novel cephalosporin/β-lactamase inhibitor combination with activity against multidrug-resistant gram-negative bacilli.

PubMed

Zhanel, George G; Chung, Phillip; Adam, Heather; Zelenitsky, Sheryl; Denisuik, Andrew; Schweizer, Frank; Lagacé-Wiens, Philippe R S; Rubinstein, Ethan; Gin, Alfred S; Walkty, Andrew; Hoban, Daryl J; Lynch, Joseph P; Karlowsky, James A

2014-01-01

Ceftolozane is a novel cephalosporin currently being developed with the β-lactamase inhibitor tazobactam for the treatment of complicated urinary tract infections (cUTIs), complicated intra-abdominal infections (cIAIs), and ventilator-associated bacterial pneumonia (VABP). The chemical structure of ceftolozane is similar to that of ceftazidime, with the exception of a modified side-chain at the 3-position of the cephem nucleus, which confers potent antipseudomonal activity. As a β-lactam, its mechanism of action is the inhibition of penicillin-binding proteins (PBPs). Ceftolozane displays increased activity against Gram-negative bacilli, including those that harbor classical β-lactamases (e.g., TEM-1 and SHV-1), but, similar to other oxyimino-cephalosporins such as ceftazidime and ceftriaxone, it is compromised by extended-spectrum β-lactamases (ESBLs) and carbapenemases. The addition of tazobactam extends the activity of ceftolozane to include most ESBL producers as well as some anaerobic species. Ceftolozane is distinguished from other cephalosporins by its potent activity versus Pseudomonas aeruginosa, including various drug-resistant phenotypes such as carbapenem, piperacillin/tazobactam, and ceftazidime-resistant isolates, as well as those strains that are multidrug-resistant (MDR). Its antipseudomonal activity is attributed to its ability to evade the multitude of resistance mechanisms employed by P. aeruginosa, including efflux pumps, reduced uptake through porins and modification of PBPs. Ceftolozane demonstrates linear pharmacokinetics unaffected by the coadministration of tazobactam; specifically, it follows a two-compartmental model with linear elimination. Following single doses, ranging from 250 to 2,000 mg, over a 1-h intravenous infusion, ceftolozane displays a mean plasma half-life of 2.3 h (range 1.9-2.6 h), a steady-state volume of distribution that ranges from 13.1 to 17.6 L, and a mean clearance of 102.4 mL/min. It demonstrates low plasma protein binding (20 %), is primarily eliminated via urinary excretion (≥92 %), and may require dose adjustments in patients with a creatinine clearance <50 mL/min. Time-kill experiments and animal infection models have demonstrated that the pharmacokinetic-pharmacodynamic index that is best correlated with ceftolozane's in vivo efficacy is the percentage of time in which free plasma drug concentrations exceed the minimum inhibitory concentration of a given pathogen (%fT >MIC), as expected of β-lactams. Two phase II clinical trials have been conducted to evaluate ceftolozane ± tazobactam in the settings of cUTIs and cIAIs. One trial compared ceftolozane 1,000 mg every 8 h (q8h) versus ceftazidime 1,000 mg q8h in the treatment of cUTI, including pyelonephritis, and demonstrated similar microbiologic and clinical outcomes, as well as a similar incidence of adverse effects after 7-10 days of treatment, respectively. A second trial has been conducted comparing ceftolozane/tazobactam 1,000/500 mg and metronidazole 500 mg q8h versus meropenem 1,000 mg q8h in the treatment of cIAI. A number of phase I and phase II studies have reported ceftolozane to possess a good safety and tolerability profile, one that is consistent with that of other cephalosporins. In conclusion, ceftolozane is a new cephalosporin with activity versus MDR organisms including P. aeruginosa. Tazobactam allows the broadening of the spectrum of ceftolozane versus β-lactamase-producing Gram-negative bacilli including ESBLs. Potential roles for ceftolozane/tazobactam include empiric therapy where infection by a resistant Gram-negative organism (e.g., ESBL) is suspected, or as part of combination therapy (e.g., with metronidazole) where a polymicrobial infection is suspected. In addition, ceftolozane/tazobactam may represent alternative therapy to the third-generation cephalosporins after treatment failure or for documented infections due to Gram-negative bacilli producing ESBLs. Finally, the increased activity of ceftolozane/tazobactam versus P. aeruginosa, including MDR strains, may lead to the treatment of suspected and documented P. aeruginosa infections with this agent. Currently, ceftolozane/tazobactam is being evaluated in three phase III trials for the treatment of cUTI, cIAI, and VABP.

Meropenem use and colonization by antibiotic-resistant Gram-negative bacilli in a pediatric intensive care unit.

PubMed

Toltzis, Philip; Dul, Michael; O'Riordan, Mary Ann; Melnick, David; Lo, Mathew; Blumer, Jeffrey

2009-01-01

The carbapenems are broad-spectrum beta-lactam antibiotics with activity against most organisms encountered in the pediatric intensive care unit (PICU). In anticipation of their increased use in critically ill children, we measured the effect of sustained meropenem use on the pattern of Gram-negative bacillus colonization in patients admitted to a tertiary care PICU. : Prospective preintervention/postintervention comparison. Medical/surgical PICU. Consecutive PICU admissions over 2.5 yrs. After a 6-mo baseline period, all children with serious infections admitted to the PICU during the subsequent 2 yrs were administered meropenem. The incidence of colonization by Gram-negative bacilli resistant to one of a battery of broad-spectrum parenteral agents, and by organisms resistant specifically to meropenem, during the baseline period was compared with the period of preferred meropenem use. During the period of preferred meropenem use, the amount of meropenem used increased >seven-fold, whereas the use of other advanced generation beta-lactams was reduced by nearly 80%. The mean prevalence of colonization by antibiotic-resistant bacilli in general was not statistically altered during the period of meropenem preference (7.3 organisms/100 patient-days, vs. 9.4 organisms/100 patient-days at baseline, p < 0.09). The prevalence of colonization by Gram-negative organisms resistant specifically to meropenem was 0.61 organisms/100 patient-days during the baseline period vs. 1.04 organisms/100 patient-days during the period of meropenem preference (p < 0.30). The incidence of nosocomial infections did not change, and the prevalence of nosocomial infections caused by meropenem-resistant organisms was always <1% of all admissions during the period of meropenem preference. There was no statistically detectable effect on the prevalence of colonization by Gram-negative organisms resistant to one or more classes of broad-spectrum parenteral antibiotics, or to colonization by organisms resistant specifically to meropenem, when meropenem was the preferred antibiotic in a PICU.

Antibacterial properties of propolis (bee glue).

PubMed Central

Grange, J M; Davey, R W

1990-01-01

Propolis (bee glue) was found to have antibacterial activity against a range of commonly encountered cocci and Gram-positive rods, including the human tubercle bacillus, but only limited activity against Gram-negative bacilli. These findings confirm previous reports of antimicrobial properties of this material, possibly attributable to its high flavonoid content. PMID:2182860

The usefulness of changing focus during examination using Gram staining as initial diagnostic clue for infective tuberculosis.

PubMed

Atsukawa, Yoshiko; Kawakami, Sayoko; Asahara, Miwa; Ishigaki, Shinobu; Tanaka, Takashi; Ono, Yasuo; Nishiya, Hajime; Fujisaki, Ryuichi; Koga, Ichiro; Ota, Yasuo; Miyazawa, Yukihisa

2011-08-01

Gram staining is a useful technique for detecting bacteria but is highly questionable in detecting Mycobacterium tuberculosis. Its detection generally requires special staining, such as Ziehl-Neelsen staining. We experienced three cases in which tuberculosis was first suggested by Gram staining of sputum or pus, confirmed by Ziehl-Neelsen staining, and diagnosed by polymerase chain reaction or culture. To find colorless tubercle bacilli in clinical samples with various organisms, varying the focus to slightly longer and shorter during study of the slides is indispensable. We present criteria for detecting infective pulmonary tuberculosis in Gram staining. First, in the ordinary focus, weakly stained, thin, gram-positive bacilli are found; second, with a slightly longer focus distance, the thin, cord-like, conspicuous gram-positive bacilli can be observed; and third, with a shorter focus distance, the gram-positive bacilli have changed into the brightened, colorless, or ghost ones. Four laboratory technologists each evaluated 20 Gram-stained samples after being lectured on the criteria, with no prior information about the sample. They accurately evaluated the presence of the bacilli in Gram-stained preparations in more than 90% of samples containing 3+ bacilli on Ziehl-Neelsen staining. Gram staining is available as an easy and rapid initial clue to recognize highly infective tuberculosis.

Pneumonia in the long-term-care facility.

PubMed

Marrie, Thomas J

2002-03-01

Pneumonia is a common infection among residents of long-term-care facilities (LTCFs), with an incidence of 1.2 episodes per 1,000 patient-days. This rate is believed to be six- to tenfold higher than the rate of pneumonia among elderly individuals living in the community. The risk factors for pneumonia among residents of LTCFs are profound disability, bedridden state, urinary incontinence, difficulty swallowing, malnutrition, tube feedings, contractures, and use of benzodiazepines and anticholinergic medications. An elevated respiratory rate is often an early clue to pneumonia in this group of patients. Staphylococcus aureus (including methicillin-resistant S. aureus) and aerobic gram-negative bacilli (including multidrug-resistant isolates) are more frequent causes of pneumonia in this setting than in the community. Criteria have been developed that help identify patients for treatment in their LTCFs.

Curative Treatment of Severe Gram-Negative Bacterial Infections by a New Class of Antibiotics Targeting LpxC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemaître, Nadine; Liang, Xiaofei; Najeeb, Javaria

ABSTRACT The infectious diseases caused by multidrug-resistant bacteria pose serious threats to humankind. It has been suggested that an antibiotic targeting LpxC of the lipid A biosynthetic pathway in Gram-negative bacteria is a promising strategy for curing Gram-negative bacterial infections. However, experimental proof of this concept is lacking. Here, we describe our discovery and characterization of a biphenylacetylene-based inhibitor of LpxC, an essential enzyme in the biosynthesis of the lipid A component of the outer membrane of Gram-negative bacteria. The compound LPC-069 has no known adverse effects in mice and is effectivein vitroagainst a broad panel of Gram-negative clinical isolates,more » including several multiresistant and extremely drug-resistant strains involved in nosocomial infections. Furthermore, LPC-069 is curative in a murine model of one of the most severe human diseases, bubonic plague, which is caused by the Gram-negative bacteriumYersinia pestis. Our results demonstrate the safety and efficacy of LpxC inhibitors as a new class of antibiotic against fatal infections caused by extremely virulent pathogens. The present findings also highlight the potential of LpxC inhibitors for clinical development as therapeutics for infections caused by multidrug-resistant bacteria. IMPORTANCEThe rapid spread of antimicrobial resistance among Gram-negative bacilli highlights the urgent need for new antibiotics. Here, we describe a new class of antibiotics lacking cross-resistance with conventional antibiotics. The compounds inhibit LpxC, a key enzyme in the lipid A biosynthetic pathway in Gram-negative bacteria, and are activein vitroagainst a broad panel of clinical isolates of Gram-negative bacilli involved in nosocomial and community infections. The present study also constitutes the first demonstration of the curative treatment of bubonic plague by a novel, broad-spectrum antibiotic targeting LpxC. Hence, the data highlight the therapeutic potential of LpxC inhibitors against a wide variety of Gram-negative bacterial infections, including the most severe ones caused byY. pestisand by multidrug-resistant and extensively drug-resistant carbapenemase-producing strains.« less

Curative Treatment of Severe Gram-Negative Bacterial Infections by a New Class of Antibiotics Targeting LpxC.

PubMed

Lemaître, Nadine; Liang, Xiaofei; Najeeb, Javaria; Lee, Chul-Jin; Titecat, Marie; Leteurtre, Emmanuelle; Simonet, Michel; Toone, Eric J; Zhou, Pei; Sebbane, Florent

2017-07-25

The infectious diseases caused by multidrug-resistant bacteria pose serious threats to humankind. It has been suggested that an antibiotic targeting LpxC of the lipid A biosynthetic pathway in Gram-negative bacteria is a promising strategy for curing Gram-negative bacterial infections. However, experimental proof of this concept is lacking. Here, we describe our discovery and characterization of a biphenylacetylene-based inhibitor of LpxC, an essential enzyme in the biosynthesis of the lipid A component of the outer membrane of Gram-negative bacteria. The compound LPC-069 has no known adverse effects in mice and is effective in vitro against a broad panel of Gram-negative clinical isolates, including several multiresistant and extremely drug-resistant strains involved in nosocomial infections. Furthermore, LPC-069 is curative in a murine model of one of the most severe human diseases, bubonic plague, which is caused by the Gram-negative bacterium Yersinia pestis Our results demonstrate the safety and efficacy of LpxC inhibitors as a new class of antibiotic against fatal infections caused by extremely virulent pathogens. The present findings also highlight the potential of LpxC inhibitors for clinical development as therapeutics for infections caused by multidrug-resistant bacteria. IMPORTANCE The rapid spread of antimicrobial resistance among Gram-negative bacilli highlights the urgent need for new antibiotics. Here, we describe a new class of antibiotics lacking cross-resistance with conventional antibiotics. The compounds inhibit LpxC, a key enzyme in the lipid A biosynthetic pathway in Gram-negative bacteria, and are active in vitro against a broad panel of clinical isolates of Gram-negative bacilli involved in nosocomial and community infections. The present study also constitutes the first demonstration of the curative treatment of bubonic plague by a novel, broad-spectrum antibiotic targeting LpxC. Hence, the data highlight the therapeutic potential of LpxC inhibitors against a wide variety of Gram-negative bacterial infections, including the most severe ones caused by Y. pestis and by multidrug-resistant and extensively drug-resistant carbapenemase-producing strains. Copyright © 2017 Lemaître et al.

Gentamicin-loaded borate bioactive glass eradicates osteomyelitis due to Escherichia coli in a rabbit model.

PubMed

Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang; Zhang, Changqing

2013-07-01

The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli.

Gentamicin-Loaded Borate Bioactive Glass Eradicates Osteomyelitis Due to Escherichia coli in a Rabbit Model

PubMed Central

Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang

2013-01-01

The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli. PMID:23629702

Usability application of multiplex polymerase chain reaction in the diagnosis of microorganisms isolated from urine of patients treated in cancer hospital

PubMed Central

Cybulski, Zefiryn; Schmidt, Katarzyna; Grabiec, Alicja; Talaga, Zofia; Bociąg, Piotr; Wojciechowicz, Jacek; Roszak, Andrzej; Kycler, Witold

2013-01-01

Background The objective of this study was: i) to compare the results of urine culture with polymerase chain reaction (PCR) -based detection of microorganisms using two commercially available kits, ii) to assess antimicrobial susceptibility of urine isolates from cancer patients to chosen antimicrobial drugs and, if necessary, to update the recommendation of empirical therapy. Materials and methods. A one-year hospital-based prospective study has been conducted in Greater Poland Cancer Centre and Genetic Medicine Laboratory CBDNA Research Centre in 2011. Urine cultures and urine PCR assay from 72 patients were examined Results Urine cultures and urine PCR assay from 72 patients were examined. Urine samples were positive for 128 strains from which 95 (74%) were identical in both tests. The most frequently isolated bacteria in both culture and PCR assay were coliform organisms and Enterococcus spp. The Gram negative bacilli were most resistant to cotrimoxazol. 77.2% of these bacilli and 100% of E. faecalis and S. agalactiae were sensitive to amoxicillin-clavulanic acid. 4.7% of Gram positive cocci were resistant to nitrofurantoin. Conclusions The PCR method quickly finds the causative agent of urinary tract infection (UTI) and, therefore, it can help with making the choice of the proper antimicrobial therapy at an early stage. It appears to be a viable alternative to the recommendations made in general treatment guidelines, in cases where diversified sensitivity patterns of microorganisms have been found. PMID:24133395

Fasting hypochlorhydria with gram positive gastric flora is highly prevalent in healthy old people.

PubMed Central

Husebye, E; Skar, V; Høverstad, T; Melby, K

1992-01-01

Fifteen healthy old people mean age 84 years (range 80-91 years), were examined to assess the effect of advanced age on the microecology of the upper gastrointestinal tract. Twelve of 15 (80%) were hypochlorhydric with pH 6.6 (0.3) (mean (SEM) and a mean bacterial count of 10(8) colony forming units (CFU) per ml (range 10(5)-10(10)) in fasting gastric aspirate. Normochlorhydric subjects had low counts (< or = 10(1) CFU/ml). The microbial flora was dominated by viridans streptococci, coagulase negative staphylococci, and Haemophilus sp. Only one subject harboured significant concentrations of Gram negative bacilli with Escherichia coli (10(4-5) CFU/ml) and Klebsiella (10(4-5)). Strict anaerobes were not found. The total concentration of short chain fatty acids in gastric aspirate was 10.6 (2.9) mmol/l (mean (SEM). Absence of significant, intraluminal fermentation of xylose to CO2 was shown by the 14C-d Xylose breath test, and ambulatory manometry showed preserved fasting motility pattern of the small intestine. Serum immunoglobulins were normal. Advanced age is accompanied by fasting hypochlorhydria and colonisation with mainly Gram positive flora in the upper gut. Other factors than old age and fasting hypochlorhydria are required for colonisation with Gram negative bacilli. PMID:1446855

Utility of Gram Staining for Evaluation of the Quality of Cystic Fibrosis Sputum Samples

PubMed Central

Nair, Bindu; Stapp, Jenny; Stapp, Lynn; Bugni, Linda; Van Dalfsen, Jill; Burns, Jane L.

2002-01-01

The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum. PMID:12149331

Utility of gram staining for evaluation of the quality of cystic fibrosis sputum samples.

PubMed

Nair, Bindu; Stapp, Jenny; Stapp, Lynn; Bugni, Linda; Van Dalfsen, Jill; Burns, Jane L

2002-08-01

The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum.

[Infection control team (ICT) in cooperation with microbiology laboratories].

PubMed

Okazaki, Mitsuhiro

2012-10-01

Infection control as a medical safety measure is an important issue in all medical facilities. In order to tackle this measure, cooperation between the infection control team (ICT) and microbiological laboratory is indispensable. Multiple drug-resistant bacteria have shifted from Gram-positive bacteria to Gram-negative bacilli within the last ten years. There are also a variety of bacilli, complicating the examination method and test results further. Therefore, cooperation between the ICT and microbiological laboratory has become important to understand examination results and to use them. In order to maintain functional cooperation, explanatory and communicative ability between the microbiological laboratory and ICT is required every day. Such positive information exchange will develop into efficient and functional ICT activity.

[Utility of MALDI-TOF MS for the identification of anaerobic bacteria].

PubMed

Zárate, Mariela S; Romano, Vanesa; Nievas, Jimena; Smayevsky, Jorgelina

2014-01-01

The analysis by MALDI-TOF MS (Matrix-assited laser desorption/ionization time-of-flight mass spectrometry) has become a reference method for the identification of microorganisms in Clinical Microbiology. However, data on some groups of microorganisms are still controversial. The aim of this study is to determine the utility of MALDI-TOF MS for the identification of clinical isolates of anaerobic bacteria. One-hundred and six anaerobic bacteria isolates were analyzed by MALDI-TOF MS and by conventional biochemical tests. In those cases where identification by conventional methodology was not applicable or in the face of discordance between sequencing methodologies, 16 S rRNA gene sequence analysis was performed. The conventional method and MALDI-TOF MS agreed at genus and species level by 95.3 %. Concordance in gram-negative bacilli was 91.4% and 100% among gram-positive bacilli; there was also concordance both in the 8 isolates studied in gram-positive cocci and in the single gram-negative cocci included. The data obtained in this study demonstrate that MALDI-TOF MS offers the possibility of adequate identification of anaerobic bacteria. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Ants as vectors of pathogenic microorganisms in a hospital in São Paulo county, Brazil.

PubMed

Máximo, Heros J; Felizatti, Henrique L; Ceccato, Marcela; Cintra-Socolowski, Priscila; Beretta, Ana Laura R Zeni

2014-08-20

The present study aimed to identify and characterize the presence of bacteria carried by ants, and check the distribution of these ants in the physical confines of a medium-sized hospital in São Paulo county, Brazil. The ants were collected from March 2012 to February 2013. Attractive non-toxic baits were used to catch the ants, and the sectors considered for the study were medical wards, outdoor areas, obstetric unit, reception area, kitchen, surgical centres, paediatric clinic and intensive care unit. Captured ants were classified using taxonomic keys and subsequently immersed in Brain Heart Infusion broth. Paratrechina spp. and Monomorium floricola ants were found most frequently in the hospital. Ants had a high capacity for carrying bacteria, and the isolates comprised 68.8% Gram-positive, spore-producing bacilli (Bacillus spp. and Listeria spp.); 14.7% Gram-negative bacilli (Pseudomonas aeruginosa and Klebsiella spp.); and 16.4% Gram-positive cocci (Streptococcus spp. and Staphylococcus aureus). Among the areas being evaluated, the medical wards had the largest number of ants captured, and therefore the most bacteria. Ants in hospitals may carry both Gram-positive and Gram-negative bacteria, and methods of controlling urban ants should be adopted and strictly adhered to, to minimize the risk of infection in hospital patients.

Emergence of colistin resistance in the largest university hospital complex of São Paulo, Brazil, over five years.

PubMed

Rossi, Flávia; Girardello, Raquel; Cury, Ana Paula; Di Gioia, Thais Sabato Romano; Almeida, João Nóbrega de; Duarte, Alberto José da Silva

Colistin resistance involving Gram-negative bacilli infections is a challenge for health institutions around of the world. Carbapenem-resistance among these isolates makes colistin the last therapeutic option for this treatment. Colistin resistance among Enterobacteriaceae, Acinetobacter spp., and Pseudomonas spp. was evaluated between 2010 and 2014 years, at Hospital das Clínicas, São Paulo, Brazil. Over five years 1346 (4.0%) colistin resistant Gram-negative bacilli were evaluated. Enterobacteriaceae was the most frequent (86.1%) pathogen isolated, followed by Acinetobacter spp. (7.6%), and Pseudomonas spp. (6.3%). By temporal analysis there was a trend for an increase of colistin resistance among Enterobacteriaceae, but not among non-fermentative isolates. Among 1346 colistin resistant isolates, carbapenem susceptibility was observed in 21.5%. Colistin resistance in our hospital has been alarmingly increased among Klebsiella pneumoniae isolates in both KPC positive and negative, thus becoming a therapeutic problem. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

A single-tube screen for Salmonella and Shigella.

PubMed

Procop, Gary W; Wallace, Jacqueline D; Tuohy, Marion J; Lasalvia, Margret M; Addison, Rachel M; Reller, L Barth

2008-08-01

Salmonella and Shigella species are routinely sought in stool specimens submitted for culture. It is a common practice to screen lactose-negative colonies by using triple sugar iron agar, lysine iron agar, and Christensen urea agar to determine if further identification is necessary. We designed and evaluated a novel combination of media, which are layered in a single tube, for screening isolates suspected to possibly represent Salmonella or Shigella. We tested this media combination with 106 Salmonella, 56 Shigella, and 56 other gram-negative bacilli. All Salmonella and Shigella isolates tested were appropriately characterized as possible Salmonella or Shigella by using an algorithm developed for use with this media combination. Similarly, 53 (95%) of 56 other gram-negative bacilli were appropriately screened as non -Salmonella and non -Shigella isolates. This unique media combination provides the most important biochemical reactions needed to screen for Salmonella and Shigella in a single-tube format, which decreases labor by two thirds (ie, 1 tube is inoculated vs 3).

Use of elastin fibre detection in the diagnosis of ventilator associated pneumonia.

PubMed

el-Ebiary, M; Torres, A; González, J; Martos, A; Puig de la Bellacasa, J; Ferrer, M; Rodriguez-Roisin, R

1995-01-01

Elastin fibre detection could be a simple and reliable marker of ventilator associated pneumonia. To confirm this, a prospective study was undertaken to evaluate the diagnostic yield of elastin fibre detection in the diagnosis of ventilator associated pneumonia. Seventy eight mechanically ventilated patients were evaluated by examining endotracheal aspirates for the presence of elastin fibres. All patients were previously treated with antibiotics. Quantitative bacterial cultures of endotracheal aspirates and protected specimen brush samples were also performed. Patients were classified into three diagnostic categories: group 1, definite pneumonia (n = 25); group 2, probable pneumonia (n = 35); and group 3, controls (n = 18). Patients with definite and probable pneumonia were grouped together. The presence of elastin fibres in endotracheal aspirate samples was more frequent in groups 1 and 2, being found in 19 of the 60 patients compared with five of the control group. Although the presence of elastin fibres had a low sensitivity (32%), it was a reasonably specific marker (72%) of pneumonia. This specificity increased to 86% and 81% respectively when only Gram negative bacilli and Pseudomonas aeruginosa pneumonia were considered. Again, calculated sensitivity was 43% and 44% when analysing cases infected by Gram negative bacilli and Ps aeruginosa, respectively. The negative predictive value of the detection of elastin fibres in pneumonia caused by Ps aeruginosa was 81%. Detection was more frequent with infection by Gram negative bacilli (14/19), particularly with Ps aeruginosa (8/14). By contrast, pneumonia due to Gram positive cocci or non-bacterial agents uncommonly resulted in positive elastin fibre preparations (4/19, 21%). When analysing patients with and without chronic obstructive pulmonary disease, the diagnostic value of elastin fibre detection did not change. Potassium hydroxide preparation of elastin fibres is a rapid and simple specific marker of ventilator associated pneumonia and may be a useful technique to help diagnose pulmonary infections in mechanically ventilated patients, although this assessment is at present limited to patients without adult respiratory distress syndrome.

Use of elastin fibre detection in the diagnosis of ventilator associated pneumonia.

PubMed Central

el-Ebiary, M.; Torres, A.; González, J.; Martos, A.; Puig de la Bellacasa, J.; Ferrer, M.; Rodriguez-Roisin, R.

1995-01-01

BACKGROUND--Elastin fibre detection could be a simple and reliable marker of ventilator associated pneumonia. To confirm this, a prospective study was undertaken to evaluate the diagnostic yield of elastin fibre detection in the diagnosis of ventilator associated pneumonia. METHODS--Seventy eight mechanically ventilated patients were evaluated by examining endotracheal aspirates for the presence of elastin fibres. All patients were previously treated with antibiotics. Quantitative bacterial cultures of endotracheal aspirates and protected specimen brush samples were also performed. Patients were classified into three diagnostic categories: group 1, definite pneumonia (n = 25); group 2, probable pneumonia (n = 35); and group 3, controls (n = 18). RESULTS--Patients with definite and probable pneumonia were grouped together. The presence of elastin fibres in endotracheal aspirate samples was more frequent in groups 1 and 2, being found in 19 of the 60 patients compared with five of the control group. Although the presence of elastin fibres had a low sensitivity (32%), it was a reasonably specific marker (72%) of pneumonia. This specificity increased to 86% and 81% respectively when only Gram negative bacilli and Pseudomonas aeruginosa pneumonia were considered. Again, calculated sensitivity was 43% and 44% when analysing cases infected by Gram negative bacilli and Ps aeruginosa, respectively. The negative predictive value of the detection of elastin fibres in pneumonia caused by Ps aeruginosa was 81%. Detection was more frequent with infection by Gram negative bacilli (14/19), particularly with Ps aeruginosa (8/14). By contrast, pneumonia due to Gram positive cocci or non-bacterial agents uncommonly resulted in positive elastin fibre preparations (4/19, 21%). When analysing patients with and without chronic obstructive pulmonary disease, the diagnostic value of elastin fibre detection did not change. CONCLUSIONS--Potassium hydroxide preparation of elastin fibres is a rapid and simple specific marker of ventilator associated pneumonia and may be a useful technique to help diagnose pulmonary infections in mechanically ventilated patients, although this assessment is at present limited to patients without adult respiratory distress syndrome. PMID:7886642

Nosocomial bloodstream infections in a Turkish university hospital: study of Gram-negative bacilli and their sensitivity patterns.

PubMed

Köseoğlu , O; Kocagöz, S; Gür, D; Akova, M

2001-06-01

Treatment of nosocomial bacteraemia is usually governed by the surveillance results of the particular unit. Such results are especially important when antimicrobial resistance rates are high. Multiresistant isolates including Gram-negatives producing extended-spectrum beta-lactamases have been frequently reported in tertiary care units in Turkey. In this study, antimicrobial susceptibilities of Gram-negative blood isolates (n=348) were determined by microbroth dilution tests. The results showed carbapenems (meropenem and imipenem) to be uniformly more potent in vitro than any other drug against the Enterobacteriaceae. Quinolone antibiotics were more active in vitro than aminoglycosides against a range of bacteria. Gram-negative bloodstream isolates were highly resistant to many antimicrobial agents in the hospital. In order to prevent hospital infection and antimicrobial resistance, surveillance of aetiological agents must be performed regularly.

Port type is a possible risk factor for implantable venous access port-related bloodstream infections and no sign of local infection predicts the growth of gram-negative bacilli.

PubMed

Hsu, Jui-Feng; Chang, Hsu-Liang; Tsai, Ming-Ju; Tsai, Ying-Ming; Lee, Yen-Lung; Chen, Pei-Huan; Fan, Wen-Chieh; Su, Yu-Chung; Yang, Chih-Jen

2015-09-30

Implantable venous access port (IVAP)-related blood stream infections (BSIs) are one of the most common complications of implantable venous ports. The risk factors and pathogens for IVAP-related BSIs are still controversial. We retrospectively reviewed all patients who received IVAPs at a Hospital in Taiwan from January 1, 2011 to June 31, 2014. Two types of venous port, BardPort® 6.6 fr (Bard port) and Autosuture Chemosite® 7.5 fr (TYCO port) were used. All patients with clinically proven venous port-related BSIs were enrolled. A total of 552 patients were enrolled. There were 34 episodes of IVAP-related BSIs during the study period for a total incidence of 0.177 events/1000 catheter days. Port type (TYCO vs. Bard, HR = 7.105 (95% confidence interval (CI), 1.688-29.904), p = 0.0075), age > 65 years (HR = 2.320 (95 % CI, 1.179-4.564), p = 0.0148), and lung cancer (HR = 5.807 (95% CI, 2.946-11.447), p < 0.001) were risk factors for port infections. We also found that no local sign of infection was significantly associated with the growth of gram-negative bacilli (p = 0.031). TYCO venous ports, age > 65 years, and lung cancer were all significant risk factors for IVAP-related BSIs, and no sign of infection was significantly associated with the growth of gram-negative bacilli.

Patient cytokine response in transfusion-associated sepsis.

PubMed Central

McAllister, S K; Bland, L A; Arduino, M J; Aguero, S M; Wenger, P N; Jarvis, W R

1994-01-01

Cytokine concentrations in plasma from patients transfused with packed erythrocytes contaminated with gram-negative bacilli were measured. Cytokine concentrations in posttransfusion plasma were significantly elevated. A difference in cytokine patterns between survivors and a nonsurvivor was observed. PMID:8168982

Bloodstream infections in patients with solid tumors

PubMed Central

Gudiol, Carlota; Aguado, José María; Carratalà, Jordi

2016-01-01

ABSTRACT Little information is currently available regarding bloodstream infection (BSI) in patients with solid tumors who, for a variety of reasons, are particularly predisposed to develop this condition. In this review we focus on the incidence, epidemiology, clinical features, etiology, antimicrobial resistance, and outcomes of BSI of adult cancer patients with solid tumors. Most episodes of BSI occur in non-neutropenic patients, in whom the site of primary or metastatic tumor often serves as the portal of entry. The urinary tract and the abdomen are the most frequent sources of infection, and cholangitis is the most common recurrent source of BSI. Gram-negative bacilli are becoming the leading cause of BSI in patients with solid tumors, and the rate of multidrug resistance is increasingly being recognized. The case-fatality rate in patients with solid tumors and BSI is high, especially among those with comorbidities, advanced neoplasms, corticosteroid therapy, and shock at presentation. PMID:26787095

Microbiology of liver abscesses and the predictive value of abscess gram stain and associated blood cultures.

PubMed

Chemaly, Roy F; Hall, Gerri S; Keys, Thomas F; Procop, Gary W

2003-08-01

Although rare, pyogenic liver abscesses are potentially fatal. We evaluated the predictive value of Gram stain of liver abscess aspirates and temporally associated blood cultures. Gram stains detected bacteria in 79% of the liver abscesses tested. The sensitivity and specificity of Gram stain of the liver abscesses were 90% and 100% for Gram-positive cocci (GPC) and 52% and 94% for Gram-negative bacilli (GNB). The sensitivities of the blood cultures for any GPC and GNB present in the liver abscess were 30% and 39%, respectively. Although, Gram stains and blood cultures offer incomplete detection of the microbial contents of pyogenic liver abscesses, both tests should always accompany liver abscess cultures.

Antimicrobial susceptibility profiles of gram-negative bacteria causing infections collected across India during 2014-2016: Study for monitoring antimicrobial resistance trend report.

PubMed

Veeraraghavan, Balaji; Jesudason, Mark Ranjan; Prakasah, John Antony Jude; Anandan, Shalini; Sahni, Rani Diana; Pragasam, Agila Kumari; Bakthavatchalam, Yamuna Devi; Selvakumar, Rajesh Joseph; Dhole, T N; Rodrigues, Camilla; Roy, Indranil; Joshi, Sangeetha; Chaudhuri, Bhaskar Narayan; Chitnis, D S

2018-01-01

The emergence of antibiotic resistance among bacterial pathogens in the hospital and community has increased the concern to the health-care providers due to the limited treatment options. Surveillance of antimicrobial resistance (AMR) in frequently isolated bacterial pathogens causing severe infections is of great importance. The data generated will be useful for the clinicians to decide empiric therapy on the local epidemiological resistance profile of the antimicrobial agents. This study aims to monitor the distribution of bacterial pathogen and their susceptibility pattern to the commonly used antimicrobial agents. This study includes Gram-negative bacilli collected from intra-abdominal, urinary tract and respiratory tract infections during 2014-2016. Isolates were collected from seven hospitals across India. All the study isolates were characterised up to species level, and minimum inhibitory concentration was determined for a wide range of antimicrobials included in the study panel. The test results were interpreted as per standard Clinical Laboratory Standards Institute guidelines. A total of 2731 isolates of gram-negative bacteria were tested during study period. The most frequently isolated pathogens were 44% of Escherichia coli (n = 1205) followed by 25% of Klebsiella pneumoniae (n = 676) and 11% of Pseudomonas aeruginosa (n = 308). Among the antimicrobials tested, carbapenems were the most active, followed by amikacin and piperacillin/tazobactam. The rate of extended-spectrum beta-lactamase (ESBL)-positive isolates were ranged from 66%-77% in E. coli to 61%-72% in K. pneumoniae, respectively. Overall, colistin retains its activity in > 90% of the isolates tested and appear promising. Increasing rates of ESBL producers have been noted, which is alarming. Further, carbapenem resistance was also gradually increasing, which needs much attention. Overall, this study data show that carbapenems, amikacin and colistin continue to be the best agents available to treat drug-resistant infections. Thus continuous monitoring of susceptibility profile of the clinically important Gram-negative pathogens is of great importance to guide effective antimicrobial therapy.

Urinary tract infections following radical cystectomy and urinary diversion: a review of 1133 patients.

PubMed

Clifford, Thomas G; Katebian, Behrod; Van Horn, Christine M; Bazargani, Soroush T; Cai, Jie; Miranda, Gus; Daneshmand, Siamak; Djaladat, Hooman

2018-05-01

To investigate the incidence and microbiology of urinary tract infection (UTI) within 90 days following radical cystectomy (RC) and urinary diversion. We reviewed 1133 patients who underwent RC for bladder cancer at our institution between 2003 and 2013; 815 patients (72%) underwent orthotopic diversion, 274 (24%) ileal conduit, and 44 (4%) continent cutaneous diversion. 90-day postoperative UTI incidence, culture results, antibiotic sensitivity/resistance and treatment were recorded through retrospective review. Fisher's exact test, Kruskal-Wallis test, and multivariable analysis were performed. A total of 151 urinary tract infections were recorded in 123 patients (11%) during the first 90 days postoperatively. 21/123 (17%) had multiple infections and 25 (20%) had urosepsis in this time span. Gram-negative rods were the most common etiology (54% of positive cultures). 52% of UTI episodes led to readmission. There was no significant difference in UTI rate, etiologic microbiology (Gram-negative rods, Gram-positive cocci, fungi), or antibiotic sensitivity and resistance patterns between diversion groups. Resistance to quinolones was evident in 87.5% of Gram-positive and 35% of Gram-negative bacteria. In multivariable analysis, Charlson Comorbidity Index > 2 was associated with higher 90-day UTI rate (OR = 1.8, 95% CI 1.1-2.9, p = 0.05) and Candida UTI (OR 5.6, 95% CI 1.6-26.5, p = 0.04). UTI is a common complication and cause of readmission following radical cystectomy and urinary diversion. These infections are commonly caused by Gram-negative rods. High comorbidity index is an independent risk factor for postoperative UTI, but diversion type is not.

9 CFR 145.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... Domesticated. Propagated and maintained under the control of a person. Equivalent or equivalent requirements... provisions of the Plan; (2) As applied to non-Plan but equivalent State poultry improvement programs. The... of this chapter, those organisms which are gram negative, non spore-forming bacilli, which ferment...

9 CFR 145.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

.... Domesticated. Propagated and maintained under the control of a person. Equivalent or equivalent requirements... provisions of the Plan; (2) As applied to non-Plan but equivalent State poultry improvement programs. The... of this chapter, those organisms which are gram negative, non spore-forming bacilli, which ferment...

[Antimicrobial susceptibility testing in clinically relevant non-fermenting gram-negative bacilli: recommendations from the Antimicrobial Agents Subcommittee of the Sociedad Argentina de Bacteriología, Micología y Parasitología Clínicas, Asociación Argentina de Microbiología].

PubMed

Radice, Marcela; Marín, Marcelo; Giovanakis, Marta; Vay, Carlos; Almuzara, Marisa; Limansky, Adriana; Casellas, José M; Famiglietti, Angela; Quinteros, Mirta; Bantar, Carlos; Galas, Marcelo; Kovensky Pupko, Jaime; Nicola, Federico; Pasterán, Fernando; Soloaga, Rolando; Gutkind, Gabriel

2011-01-01

This document contains the recommendations for antimicrobial susceptibility testing of the clinically relevant non-fermenting gram-negative bacilli (NFGNB), adopted after conforming those from international committees to the experience of the Antimicrobial Agents Subcommittee members and invited experts. This document includes an update on NFGNB classification and description, as well as some specific descriptions regarding natural or frequent antimicrobial resistance and a brief account of associated resistance mechanisms. These recommendations not only suggest the antimicrobial drugs to be evaluated in each case, but also provide an optimization of the disk diffusion layout and a selection of results to be reported. Finally, this document also includes a summary of the different methodological approaches that may be used for detection and confirmation of emerging b-lactamases, such as class A and B carbapenemases.

Evaluation of Five Chromogenic Agar Media and the Rosco Rapid Carb Screen Kit for Detection and Confirmation of Carbapenemase Production in Gram-Negative Bacilli

PubMed Central

Gilmour, Matthew W.; DeGagne, Pat; Nichol, Kim; Karlowsky, James A.

2014-01-01

An efficient workflow to screen for and confirm the presence of carbapenemase-producing Gram-negative bacilli was developed by evaluating five chromogenic screening agar media and two confirmatory assays, the Rapid Carb screen test (Rosco Diagnostica A/S, Taastrup, Denmark) and the modified Hodge test. A panel of 150 isolates was used, including 49 carbapenemase-producing isolates representing a variety of β-lactamase enzyme classes. An evaluation of analytical performance, assay cost, and turnaround time indicated that the preferred workflow (screening test followed by confirmatory testing) was the chromID Carba agar medium (bioMérieux, Marcy l'Étoile, France), followed by the Rapid Carb screen test, yielding a combined sensitivity of 89.8% and a specificity of 100%. As an optional component of the workflow, a determination of carbapenemase gene class via molecular means could be performed subsequent to confirmatory testing. PMID:25355764

A Review of Ten Years of the Study for Monitoring Antimicrobial Resistance Trends (SMART) from 2002 to 2011.

PubMed

Morrissey, Ian; Hackel, Meredith; Badal, Robert; Bouchillon, Sam; Hawser, Stephen; Biedenbach, Douglas

2013-11-01

Surveillance of antimicrobial agent resistance provides important information to guide microbiologists and infectious disease specialists understanding of the control and the spread of resistance mechanisms within the local environment. Continued monitoring of antimicrobial resistance patterns in the community and in local hospital environments is essential to guide effective empiric therapy. The Study for Monitoring Antimicrobial Resistance Trends (SMART) has monitored the in vitro susceptibility patterns of clinical Gram-negative bacilli to antimicrobial agents collected worldwide from intra-abdominal infections since 2002 and urinary tract infections since 2009. Resistance trends, with a particular focus on carbapenem resistance and the rate of extended-spectrum β-lactamases (ESBLs), were analyzed. Isolates from intra-abdominal infections (n = 92,086) and urinary-tract infections (n = 24,705) were collected and tested using Clinical and Laboratory Standards Institute methods. This review presents carbapenem susceptibility and ESBL rates over ten years of SMART study analysis, including key publications during this period. The SMART study has proved to be a valuable resource in determining pathogen prevalence and antibiotic susceptibility over the last ten years and continues to provide evidence for regulatory susceptibility breakpoints and clinical decision making.

[Ants as carriers of microorganisms in hospital environments].

PubMed

Pereira, Rogério Dos Santos; Ueno, Mariko

2008-01-01

Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

9 CFR 145.1 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Agriculture. Domesticated. Propagated and maintained under the control of a person. Equivalent or equivalent... bacilli. For the purpose of this chapter, those organisms which are gram negative, non spore-forming... classification on one farm; (2) As applied to disease control. All of the poultry on one farm except that, at the...

9 CFR 145.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Agriculture. Domesticated. Propagated and maintained under the control of a person. Equivalent or equivalent... bacilli. For the purpose of this chapter, those organisms which are gram negative, non spore-forming... classification on one farm; (2) As applied to disease control. All of the poultry on one farm except that, at the...

9 CFR 145.1 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Agriculture. Domesticated. Propagated and maintained under the control of a person. Equivalent or equivalent... bacilli. For the purpose of this chapter, those organisms which are gram negative, non spore-forming... classification on one farm; (2) As applied to disease control. All of the poultry on one farm except that, at the...

Antimicrobial sensitivity pattern of bacterial pathogens in urinary tract infections in South Delhi, India.

PubMed

Akhtar, Mohammad Shabib; Mohsin, Nehal; Zahak, Ahmad; Ain, Mohammad Ruhal; Pillai, P K; Kapur, Prem; Ahmad, Mohammad Zaki

2014-01-01

Seventy-four bacterial proven cases of urinary tract infections were studied, and identified by Mac Conkey agar and blood agar medium separately; all the isolates were subjected to antimicrobial sensitivity testing by Stokes technique. Ninty-six percent of total isolated organisms were found to be gram negative while remaining 4% were gram positive. Among gram negatives, E. coli and gram positive S. aureus were the most prevalent organisms. The percentage of gram negative isolates were as follows, E. coli (79.7%) followed by Klebsiella (9.5%), Pseudomonas, Acinetobacter were (2.7% each), Proteus constituted (1.4%). and among gram positive S. aureus (4%). The antibiotic resistance of identified organisms was carried out by disc-diffusion method with commercially available disc of thirteen antibiotics having different mode of actions such as inhibition of cell wall synthesis, membrane permeability alternatives, inhibition of protein synthesis and DNA synthesis inhibitors. Gram negatives showed more resistance to these antibiotics as compared to gram positive organisms. The most effective antibiotic for gram negative UTI isolates is amikacin showing 63% efficacy followed by Cefotaxime 55% efficacy, Amoxicillin and Ciprofloxacin with (49% each) efficacy. Among gram positives, Chloramphenicol, Co-trimoxazole, Gentamicin, Amikacin, Ciprofloxacin and Cefotaxime are most effective with (66.6% each) efficacy, then Ampicillin, Amoxicillin, Tetracycline and norfloxacin with (33.3% each) efficacy.

Complete Genome Sequences for 59 Burkholderia Isolates, Both Pathogenic and Near Neighbor

DOE PAGES

Johnson, Shannon L.; Bishop-Lilly, Kimberly A.; Ladner, Jason T.; ...

2015-04-30

The genus Burkholderia encompasses both pathogenic (including Burkholderia mallei and Burkholderia pseudomallei, U.S. Centers for Disease Control and Prevention Category B listed), and nonpathogenic Gram-negative bacilli. Presented in this document are full genome sequences for a panel of 59 Burkholderia strains, selected to aid in detection assay development.

Development of rapid phenotypic system for the identification of Gram-negative oxidase-positive bacilli in resource-limited settings.

PubMed

Kazmi, Mahmooda; Khan, Adnan; Kazmi, Shahana Urooj

2013-06-01

Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology. The diagnosis and surveillance of diseases is dependent, to a great extent, on laboratory services, which cannot function without effective reliable reagents and diagnostics. Despite the advancement in microbiology diagnosis globally, resourcelimited countries still struggle to provide an acceptable diagnosis quality which helps in clinical disease management and improve their mortality and morbidity data. During this study an indigenous product, Quick Test Strip (QTS) NE, was developed for the rapid identification of biochemically slower group of Gram-negative oxidase-positive bacilli that covers 19 different bacterial genera. Some of the members belonging to these groups are well-established human pathogens, e.g. various species of Vibrio, Pseudomonas, Burkholderia, Aeromonas, Achromobacter and Stenotrophomonas. This study also evaluates the performance of QTS-NE by comparing with genotypic characterization methods. A total of 232 clinical and reference bacterial isolates were tested by three different methods. QTSNE provides 100 percent concordant results with other rapid identification and molecular characterization methods and confirms the potential to be used in clinical diagnosis.

Identification of gram-negative bacilli using the Autobac IDX.

PubMed

Burdash, N M; Welborn, A L; Teti, G; Bannister, E R; Manos, J P

1985-01-01

The Autobac IDX is a new system for the rapid identification of clinically significant members of the Enterobacteriaceae and Aeromonas, Acinetobacter, Alcaligenes, Flavobacterium, Moraxella, and Pseudomonas species. The use of 18 differentially inhibitory compounds such as dyes and antibiotics along with a computerized algorithm based on a multivariate analysis provides the basis for the identification of 30 different groups of gram-negative bacilli. Required preliminary tests include observations on the presence or absence of swarming on a sheep blood agar plate and noting the following: growth, lactose fermentation, and bile precipitation from a MacConkey plate. Spot indole and spot oxidase tests must be performed as well. Identification by the Autobac IDX System takes 3-6 hr after completion of the preliminary tests. From a total of 403 isolates tested, the Autobac system agreed with the MicroID AND N/F systems on 382 identifications (94.8%). Four isolates, two Acinetobacter anitratus, one Serratia marcescens and one Moraxella osloensis could not be identified by IDX. Additional testing was required on 35 (8.7%) of the isolates.

[Test evaluation and strategy proposal to detect and to characterize carbapenemase-producing gram negative bacilli].

PubMed

Muñoz, Constanza; Zumarán, Cecilia; González, Tamara; Wozniak, Aniela; Castillo, Claudia; García, Patricia

2017-08-01

The detection of carbapenemase-producing gram negative bacilli is complicated, because there are available multiple options of test. The confirmation of the enzyme by molecular characterization is not available in all laboratories in our country. To propose a fast, efficient and simple strategy to detect and confirm CPB. 39 CPB isolates and 8 non-producing were used to evaluate the phenotypic test Carba NP, CarbAcineto NP and Blue-Carba, validating the test Xpert® Carba-R, to be used directly with bacterial colonies with conventional PCR. The sensitivity of Carba NP, CarbAcineto NP and Blue-Carba was 79,5; 87,2 y 84,6%, respectively; and specificity was 79.5; 87.2 and 84.6%, respectively. The limit of detection of Xpert® Carba-R was different for each carbapenemasa: 40.8 ufc/reaction to KPC and NDM and 30.6 ufc/reaction to VIM. On isolates with decreased susceptibility to carbapenems we propose to use as screening the test CarbAcineto NP, follow by Xpert®Carba-R to characterize the carbapenemase and adopt specific infection control measures.

Optimizing empiric therapy for Gram-negative bloodstream infections in children.

PubMed

Chao, Y; Reuter, C; Kociolek, L K; Patel, R; Zheng, X; Patel, S J

2018-06-01

Antimicrobial stewardship can be challenging in children with bloodstream infections (BSIs) caused by Gram-negative bacilli (GNB). This retrospective cohort study explored how data elements in the electronic health record could potentially optimize empiric antibiotic therapy for BSIs caused by GNB, via the construction of customized antibiograms for categorical GNB infections and identification of opportunities to minimize organism-drug mismatch and decrease time to effective therapy. Our results suggest potential strategies that could be implemented at key decision points in prescribing at initiation, modification, and targeting of therapy. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Case of Mycobacterium tuberculosis meningitis: Gram staining as a useful initial diagnostic clue for tuberculous meningitis.

PubMed

Kawakami, Sayoko; Kawamura, Yasuyosi; Nishiyama, Kyouhei; Hatanaka, Hiroki; Fujisaki, Ryuichi; Ono, Yasuo; Miyazawa, Yukihisa; Nishiya, Hajime

2012-12-01

A 32-year-old man was admitted to our hospital because of fever, headache, and loss of consciousness. Four days before admission, he had had difficulty speaking. On the day of admission, his colleague had found him to be unconscious and lying on his back. He was admitted to our hospital. The temperature at the eardrum was 35.2°C. Neurologic evaluation was negative. Computed tomography (CT) scan of the brain showed slight ventricular enlargement bilaterally. An X-ray film of the chest showed no abnormality. On the second hospital day, neck stiffness was noted. The cerebrospinal fluid (CSF) contained 870 white cells/μl, most of which were neutrophils; the glucose level in the CSF was 10 mg/dl, and the protein level was 140 mg/dl. Stained smears of the CSF, including Gram staining and India-ink preparations, disclosed no microorganisms. Capsular antigen tests for several bacteria were negative. Antimicrobial agents were started. However, by changing the microscope focus slightly while viewing Gram stains of the CSF, we could see brightened and Gram-positive bacilli that had been phagocytosed by neutrophils. This finding suggested the presence of Mycobacterium tuberculosis. Ziehl-Neelsen staining of the CSF and gastric juice revealed anti-acid bacilli. Polymerase chain reaction for M. tuberculosis in the gastric juice was positive. This case showed that Gram staining could be useful as an initial adjunct for the diagnosis of tuberculous meningitis, particularly when the CSF shows predominantly neutrocytic pleocytosis, but no other evidence of bacterial meningitis.

[Anaerobic bacteria isolated from patients with suspected anaerobic infections].

PubMed

Ercis, Serpil; Tunçkanat, Ferda; Hasçelik, Gülşen

2005-10-01

The study involved 394 clinical samples sent to the Clinical Microbiology Laboratory of Hacettepe University Adult Hospital between January 1997 and May 2004 for anaerobic cultivation. Since multiple cultures from the same clinical samples of the same patient were excluded, the study was carried on 367 samples. The anaerobic cultures were performed in anaerobic jar using AnaeroGen kits (Oxoid, Basingstoke, U.K.) or GENbox (bioMérieux, Lyon, France). The isolates were identified by both classical methods and "BBL Crystal System" (Becton Dickinson, U.S.A.). While no growth was detected in 120 (32.7%) of the clinical samples studied, in 144 samples (39.2%) only aerobes, in 28 (7.6%) only anaerobes and in 75 (20.5%) of the samples both aerobes and anaerobes were isolated. The number of the anaerobic isolates was 217 from 103 samples with anaerobic growth. Of these 103 samples 15 showed single bacterial growth whereas in 88 samples multiple bacterial isolates were detected. Anaerobic isolates consisted of 92 Gram negative bacilli (Bacteroides spp. 50, Prevotella spp. 14, Porphyromonas spp. 10, Fusobacterium spp. 7, Tisierella spp. 2, unidentified 9), 57 Gram positive bacilli (Clostridium spp.17, Propionibacterium spp. 16, Lactobacillus spp. 8, Actinomyces spp. 5, Eubacterium spp. 2, Bifidobacterium adolescentis 1, Mobiluncus mulieris 1, unidentified nonspore forming rods 7), 61 Gram positive cocci (anaerobic cocci 44, microaerophilic cocci 17), and 7 Gram negative cocci (Veillonella spp.). In conclusion, in the samples studied with prediagnosis of anaerobic infection, Bacteroides spp. (23%) were the most common bacteria followed by anaerobic Gram positive cocci (20.3%) and Clostridium spp (7.8%).

Isolation and determination of four potential antimicrobial components from Pseudomonas aeruginosa extracts

PubMed Central

Xu, Ling-Qing; Zeng, Jian-Wen; Jiang, Chong-He; Wang, Huan; Li, Yu-Zhen; Wen, Wei-Hong; Li, Jie-Hua; Wang, Feng; Ting, Wei-Jen; Sun, Zi-Yong; Huang, Chih-Yang

2017-01-01

Background: Pseudomonas aeruginosa can cause disease and also can be isolated from the skin of healthy people. Additionally, it exhibits certain antimicrobial effects against other microorganisms. Methods: We collected 60 strains of P. aeruginosa and screened their antimicrobial effects against Staphylococcus aureus (ATCC 25923) using the filter paper-disk method, the cross-streaking method and the co-culture method and then evaluated the antimicrobial activity of the chloroform-isolated S. aureus extracts against methicillin-resistant S. aureus (MRSA, Gram-positive cocci), vancomycin intermediate-resistant S. aureus (VISA, Gram-positive cocci), Corynebacterium spp. (CS, Gram-positive bacilli), Acinetobacter baumannii (AB, Gram-negative bacilli), Moraxella catarrhalis (MC, Gram-negative diplococcus), Candida albicans (CA, fungi), Candida tropicalis (CT, fungi), Candida glabrata (CG, fungi) and Candida parapsilosis (CP, fungi). Results: The PA06 and PA46 strains have strong antimicrobial effects. High-performance liquid chromatography (HPLC) analysis revealed that the major components of PA06 and PA46 that exhibit antimicrobial activity are functionally similar to phenazine-1-carboxylic acid (PCA) and pyocyanin. Preparative HPLC was performed to separate and isolate the 4 major potential antimicrobial components: PA06ER10, PA06ER16, PA06ER23 and PA06ER31. Further, the molecular masses of PA06ER10 (260.1), PA06ER16 (274.1), PA06ER23 (286.1) and PA06ER31 (318.2) were determined by electrospray ionization (ESI) mass spectrometry. Conclusion: P. aeruginosa can produce small molecules with potential antimicrobial activities against MRSA, VISA, CS, MC, CA, CT, CG and CP but not against AB. PMID:29200950

Antimicrobial Susceptibility of Enteric Gram Negative Facultative Anaerobe Bacilli in Aerobic versus Anaerobic Conditions

PubMed Central

Amachawadi, Raghavendra G.; Renter, David G.; Volkova, Victoriya V.

2016-01-01

Antimicrobial treatments result in the host’s enteric bacteria being exposed to the antimicrobials. Pharmacodynamic models can describe how this exposure affects the enteric bacteria and their antimicrobial resistance. The models utilize measurements of bacterial antimicrobial susceptibility traditionally obtained in vitro in aerobic conditions. However, in vivo enteric bacteria are exposed to antimicrobials in anaerobic conditions of the lower intestine. Some of enteric bacteria of food animals are potential foodborne pathogens, e.g., Gram-negative bacilli Escherichia coli and Salmonella enterica. These are facultative anaerobes; their physiology and growth rates change in anaerobic conditions. We hypothesized that their antimicrobial susceptibility also changes, and evaluated differences in the susceptibility in aerobic vs. anaerobic conditions of generic E. coli and Salmonella enterica of diverse serovars isolated from cattle feces. Susceptibility of an isolate was evaluated as its minimum inhibitory concentration (MIC) measured by E-Test® following 24 hours of adaptation to the conditions on Mueller-Hinton agar, and on a more complex tryptic soy agar with 5% sheep blood (BAP) media. We considered all major antimicrobial drug classes used in the U.S. to treat cattle: β-lactams (specifically, ampicillin and ceftriaxone E-Test®), aminoglycosides (gentamicin and kanamycin), fluoroquinolones (enrofloxacin), classical macrolides (erythromycin), azalides (azithromycin), sulfanomides (sulfamethoxazole/trimethoprim), and tetracyclines (tetracycline). Statistical analyses were conducted for the isolates (n≥30) interpreted as susceptible to the antimicrobials based on the clinical breakpoint interpretation for human infection. Bacterial susceptibility to every antimicrobial tested was statistically significantly different in anaerobic vs. aerobic conditions on both media, except for no difference in susceptibility to ceftriaxone on BAP agar. A satellite experiment suggested that during first days in anaerobic conditions the susceptibility changes with time. The results demonstrate that assessing effects of antimicrobial treatments on resistance in the host’s enteric bacteria that are Gram negative facultative Anaerobe Bacilli requires data on the bacterial antimicrobial susceptibility in the conditions resembling those in the intestine. PMID:27191612

Community-acquired enterococcal urinary tract infections in hospitalized children.

PubMed

Marcus, Nir; Ashkenazi, Shai; Samra, Zmira; Cohen, Avner; Livni, Gilat

2012-01-01

The objectives of this study were to characterize community-acquired (CA) enterococcal urinary tract infections (UTIs) in a tertiary pediatric center and to determine risk factors for their occurrence, their association with renal abnormalities, their antibiotic susceptibility profile, and the appropriateness of the empiric antibiotic treatment, in comparison to those of Gram-negative UTIs. In a 5-year prospective clinical and laboratory study, we found that enterococcal UTIs caused 6.2% (22/355) of culture-proven CA UTIs. Compared with Gram-negative UTI, enterococcal UTI was associated with male predominance, higher rates of underlying urinary abnormalities (70 vs. 43.7%; p = 0.03) and inappropriate empiric antibiotic therapy (22 vs. 5.6%; p = 0.02), and mainly vesicoureteral reflux (53% of cases). This study highlights the importance of early detection of CA enterococcal UTIs because of their association with underlying urinary abnormalities and a high rate of inappropriate empiric antibiotic therapy. Renal imaging is recommended for children with enterococcal UTIs; Gram stain is suggested in selected cases to detect Gram-positive cocci for early diagnosis of enterococcal UTIs and initiation of appropriate antibiotics.

Antimicrobial Mechanism of Action of Surfactant Lipid Preparations in Enteric Gram-Negative Bacilli

DTIC Science & Technology

2001-12-25

The addition of EDTA/Tris to the reaction the bacterial cells in the assay time (15min). W60C (1%) mixture results in chelation of ions, facilitating... Maillard , J.Y. (1999) Do antisep- Hamouda, T., Hayes, M.M., Cao, Z. et al. (1999) A novel surfac- tics and disinfectants select for antibiotic resistance

Fluoroquinolone antimicrobial agents.

PubMed Central

Wolfson, J S; Hooper, D C

1989-01-01

The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous system toxicities occurring most commonly, but only rarely necessitating discontinuance of therapy. In 17 of 18 prospective, randomized, double-blind comparisons with another agent or placebo, fluoroquinolones were tolerated as well as or better than the comparison regimen. Bacterial resistance has been uncommonly documented but occurs, most notably with P. aeruginosa and Staphylococcus aureus and occasionally other species for which the therapeutic ratio is less favorable. Fluoroquinolones offer an efficacious, well-tolerated, and cost-effective alternative to parenteral therapies of selected infections. PMID:2680058

Cerebral vasculitis and Cardiobacterium valvarum endocarditis.

PubMed

Abraham, R; Irwin, R B; Kannappan, D; Isalska, B; Koroma, M; Younis, N

2012-11-01

We present a case of aortic and tricuspid native valve endocarditis in which Cardiobacterium valvarum was isolated from the blood culture of a 65-year-old man. Cardiobacterium valvarum is a fastidious, Gram-negative bacillus. The genus Cardiobacterium encompasses two species - Cardiobacterium valvarum and Cardiobacterium hominis. Although both species rarely feature as the aetiological agent of endocarditis, Cardiobacterium hominis has a higher incidence than Cardiobacterium valvarum. For this causative organism, we believe this is the first report of fatality prior to surgical intervention and the first clinical course to be complicated by cerebral vasculitis. Native valve endocarditis caused by Gram-negative bacilli is extremely rare and identification of isolates may require the use of reference laboratories with molecular identification techniques.

Resistance profile for pathogens causing urinary tract infection in a pediatric population, and antibiotic treatment response at a university hospital, 2010-2011.

PubMed

Vélez Echeverri, Catalina; Serna-Higuita, Lina María; Serrano, Ana Katherina; Ochoa-García, Carolina; Rojas Rosas, Luisa; María Bedoya, Ana; Suárez, Margarita; Hincapié, Catalina; Henao, Adriana; Ortiz, Diana; Vanegas, Juan José; Zuleta, John Jairo; Espinal, David

2014-01-01

Urinary tract infection (UTI) is one of the most common bacterial infections in childhood and causes acute and chronic morbidity and long-term hypertension and chronic kidney disease. To describe the demographic characteristics, infectious agents, patterns of antibiotic resistance, etiologic agent and profile of susceptibility and response to empirical treatment of UTI in a pediatric population. This is a descriptive, retrospective study. Included in the study were 144 patients, 1:2.06 male to female ratio. The most common symptom was fever (79.9%) and 31.3% had a history of previous UTI. 72.0% of the patients had positive urine leukocyte count (>5 per field), urine gram was positive in 85.0% of samples and gram negative bacilli accounted for 77.8% for the total pathogens isolated. The most frequent uropathogens isolated were Escherichia coli and Klebsiella pneumoniae. Our E.coli isolates had a susceptibility rate higher than 90% to most of the antibiotics used, but a resistance rate of 42.6% to TMP SMX and 45.5% to ampicillin sulbactam. 6.3% of E. coli was extended-spectrum beta-lactamases producer strains. The most frequent empirical antibiotic used was amikacin, which was used in 66.0% of the patients. 17 of 90 patients who underwent voiding cistouretrography (VCUG) had vesicoureteral reflux. This study revealed that E. coli was the most frequent pathogen of community acquired UTI. We found that E. coli and other uropathogens had a high resistance rate against TMP SMX and ampicillin sulbactam. In order to ensure a successful empirical treatment, protocols should be based on local epidemiology and susceptibility rates.

Resistance profile for pathogens causing urinary tract infection in a pediatric population, and antibiotic treatment response at a University Hospital, 2010-2011

PubMed Central

Vélez Echeverri, Catalina; Serrano, Ana Katherina; Ochoa-García, Carolina; Rojas Rosas, Luisa; María Bedoya, Ana; Suárez, Margarita; Hincapié, Catalina; Henao, Adriana; Ortiz, Diana; Vanegas, Juan José; Zuleta, John Jairo; Espinal, David

2014-01-01

Introduction: Urinary tract infection (UTI) is one of the most common bacterial infections in childhood and causes acute and chronic morbidity and long-term hypertension and chronic kidney disease. Objectives: To describe the demographic characteristics, infectious agents, patterns of antibiotic resistance, etiologic agent and profile of susceptibility and response to empirical treatment of UTI in a pediatric population. Methods: This is a descriptive, retrospective study. Results: Included in the study were 144 patients, 1:2.06 male to female ratio. The most common symptom was fever (79.9%) and 31.3% had a history of previous UTI. 72.0% of the patients had positive urine leukocyte count (>5 per field), urine gram was positive in 85.0% of samples and gram negative bacilli accounted for 77.8% for the total pathogens isolated. The most frequent uropathogens isolated were Escherichia coli and Klebsiella pneumoniae. Our E.coli isolates had a susceptibility rate higher than 90% to most of the antibiotics used, but a resistance rate of 42.6% to TMP SMX and 45.5% to ampicillin sulbactam. 6.3% of E. coli was extended-spectrum beta-lactamases producer strains. The most frequent empirical antibiotic used was amikacin, which was used in 66.0% of the patients. 17 of 90 patients who underwent voiding cistouretrography (VCUG) had vesicoureteral reflux. Conclusion: This study revealed that E. coli was the most frequent pathogen of community acquired UTI. We found that E. coli and other uropathogens had a high resistance rate against TMP SMX and ampicillin sulbactam. In order to ensure a successful empirical treatment, protocols should be based on local epidemiology and susceptibility rates. PMID:24970958

Rapid and reliable identification of Gram-negative bacteria and Gram-positive cocci by deposition of bacteria harvested from blood cultures onto the MALDI-TOF plate.

PubMed

Barnini, Simona; Ghelardi, Emilia; Brucculeri, Veronica; Morici, Paola; Lupetti, Antonella

2015-06-18

Rapid identification of the causative agent(s) of bloodstream infections using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) methodology can lead to increased empirical antimicrobial therapy appropriateness. Herein, we aimed at establishing an easier and simpler method, further referred to as the direct method, using bacteria harvested by serum separator tubes from positive blood cultures and placed onto the polished steel target plate for rapid identification by MALDI-TOF. The results by the direct method were compared with those obtained by MALDI-TOF on bacteria isolated on solid media. Identification of Gram-negative bacilli was 100 % concordant using the direct method or MALDI-TOF on isolated bacteria (96 % with score > 2.0). These two methods were 90 % concordant on Gram-positive cocci (32 % with score > 2.0). Identification by the SepsiTyper method of Gram-positive cocci gave concordant results with MALDI-TOF on isolated bacteria in 87 % of cases (37 % with score > 2.0). The direct method herein developed allows rapid identification (within 30 min) of Gram-negative bacteria and Gram-positive cocci from positive blood cultures and can be used to rapidly report reliable and accurate results, without requiring skilled personnel or the use of expensive kits.

Efficacy of Citrilow® and Cecure® spray wash on the prevalence of aerobic and enterobacteriaceae/gram negative enteric bacilli and cattle hide quality

USDA-ARS?s Scientific Manuscript database

Bacterial cross-contamination from the haired outer surface of cattle to the inner meat as well as hide quality deterioration from bacteria are hygienic problems for meat and hide processing facilities. This study investigated spray wash treatments independently with two antimicrobials used in the ...

Emergence of Plasmid-Mediated Fosfomycin-Resistance Genes among Escherichia coli Isolates, France.

PubMed

Benzerara, Yahia; Gallah, Salah; Hommeril, Baptiste; Genel, Nathalie; Decré, Dominique; Rottman, Martin; Arlet, Guillaume

2017-09-01

FosA, a glutathione S-transferase that inactivates fosfomycin, has been reported as the cause of enzymatic resistance to fosfomycin. We show that multiple lineages of FosA-producing extended spectrum β-lactamase Escherichia coli have circulated in France since 2012, potentially reducing the efficacy of fosfomycin in treating infections with antimicrobial drug-resistant gram-negative bacilli.

Ticarcillin in Combination with Cephalothin or Gentamicin as Empiric Antibiotic Therapy in Granulocytopenic Cancer Patients

PubMed Central

Schimpff, Stephen C.; Landesman, Sheldon; Hahn, Davis M.; Standiford, Harold C.; Fortner, Clarence L.; Young, Viola Mae; Wiernik, Peter H.

1976-01-01

Ticarcillin was used in combination with either cephalothin or gentamicin as initial empiric antibiotic therapy for 127 patient trials of suspected infection in granulocytopenic cancer patients. Bacteremia was present in 20%, nonbacteremic microbiologically documented infections in 21%, clinically documented infections in 23%, and possible infections in 5%; infection was doubtful in 31%. Although Staphylococcus aureus was the most common single organism isolated (23%), gram-negative bacilli accounted for 54% of all pathogens. Both antibiotic regimens were highly efficacious, with complete resolution in 46% of bacteremias, 88% of nonbacteremic microbiologically documented infections, and 95% of clinically documented infections. Among bacteremias, 8 of 9 caused by S. aureus but only 4 of 15 (27%) caused by gram-negative bacilli were completely resolved with these antibiotic combinations. Reasons for nonresponse in bacteremias were persistent granulocytopenia, mixed infection and, in two patients, antibiotic-resistant organisms. Toxicities other than hypokalemia were minimal. Although the rate of further infections was high overall (18/127), only one occurred among the 39 patients with <4 days of antibiotic therapy. Ticarcillin in combination with either cephalothin or gentamicin was effective as initial empiric therapy of suspected infection in granulocytopenic cancer patients. PMID:795372

Should the patients colonized with extended-spectrum beta-lactamase-producing Gram-negative bacilli (E-GNB) coming to hospital from the community with pneumonia get anti-E-GNB active empirical treatment?

PubMed

Peterlin, Lara; Žagar, Mateja; Lejko Zupanc, Tatjana; Paladin, Marija; Beović, Bojana

2017-10-01

Extended-spectrum beta-lactamases are responsible for resistance of Gram-negative bacilli to several beta-lactam antibiotics, including those prescribed for treatment pneumonia. To evaluate the importance of colonization with E-GNB for the choice of empirical treatment we performed a retrospective case-control study including 156 patients, hospitalized for treatment of pneumonia from 2009 through 2013. Empirical treatment success and in-hospital survival were significantly lower in patients colonized with E-GNB compared to non-colonized (p = 0.002, p = 0.035). When comparing subgroups of colonized patients, treatment success was significantly lower in patients who were colonized with E-GNB resistant to empirical antibiotic (p = 0.010), but not in those colonized by E-GNB susceptible to empirically given antibiotic (p = 0.104). Difference in in-hospital mortality was insignificant in both subgroups (p = 0.056, p = 0.331). The results of study suggest that an anti-E-GNB active antibiotic should be used for empirical treatment of pneumonia in E-GNB colonized patients.

Identification of aerobic Gram-positive bacilli by use of Vitek MS.

PubMed

Navas, Maria; Pincus, David H; Wilkey, Kathy; Sercia, Linda; LaSalvia, Margaret; Wilson, Deborah; Procop, Gary W; Richter, Sandra S

2014-04-01

The accuracy of Vitek MS mass spectrometric identifications was assessed for 206 clinically significant isolates of aerobic Gram-positive bacilli representing 20 genera and 38 species. The Vitek MS identifications were correct for 85% of the isolates (56.3% to the species level, 28.6% limited to the genus level), with misidentifications occurring for 7.3% of the isolates.

Evolution of sensitivity to fosfomycin in bacteria isolated in 1973, 1974 and 1975 in the Servicio de Microbiologia y Epidemiologia of the 'Clinica Puerta de Hierro', Madrid.

PubMed

Dámaso, D; Moreno-López, M; Martínez-Beltrán, J

1977-01-01

The bacteriostatic activity of fosfomycin was studied in vitro against 1,243 clinical isolations of gram-positive cocci and 4,086 isolations of gram-negative bacilli that were obtained in 1973, 1974 and in the period from January to May of 1975. MIC was determined by the agar diffusion method, quantifying it by means of the standard curve that was worked out with the strain of E. coli NCTC 10,418. A slight increase in resistance was observed in the gram-positive cocci: 64 mug/ml were inhibitory for 63% of the 249 isolations obtained in 1973, 59.1% of the 716 isolations obtained in 1974, and 57.5% of the 278 isolations from 1975. A slight loss of sensitivity was also observed in the gram-negative bacilli: the aforementioned concentration of fosfomycin inhibited 36% of the 742 isolations from 1973, 33.6% of the 2,387 isolations from 1974 and 32.6% of the 957 isolations from 1975. 933 g of this antibiotic were consumed in our hospital in 1973, 4,203 g in 1974 and 957 g in 1975. The consumption rate per patient per year was 0.15, 0.72 and 0.20 g, respectively. In conclusion, although no change was observed in the sensitivity of some bacterial strains to fosfomycin, the overall study indicates a slight decrease in the sensitivity, although it does not apparently have any relationship to the consumption of fosfomycin in our hospital.

Risk factors of all-cause in-hospital mortality among Korean elderly bacteremic urinary tract infection (UTI) patients.

PubMed

Chin, Bum Sik; Kim, Myung Soo; Han, Sang Hoon; Shin, So Youn; Choi, Hee Kyung; Chae, Yun Tae; Jin, Sung Joon; Baek, Ji-Hyeon; Choi, Jun Yong; Song, Young Goo; Kim, Chang Oh; Kim, June Myung

2011-01-01

Urinary tract infection (UTI) is the most frequent cause of bacteremia/sepsis in elderly people and increasing antimicrobial resistance in uropathogens has been observed. To describe the characteristics of bacteremic UTI in elderly patients and to identify the independent risk factors of all-cause in-hospital mortality, a retrospective cohort study of bacteremic UTI patients of age over 65 was performed at a single 2000-bed tertiary hospital. Bacteremic UTI was defined as the isolation of the same organism from both urine and blood within 48 h. Eighty-six elderly bacteremic UTI patients were enrolled. Community-acquired infection was the case for most patients (79.1%), and Escherichia coli accounted for 88.6% (70/79) among Gram-negative organisms. Non-E. coli Gram-negative organisms were more frequent in hospital-acquired cases and male patients while chronic urinary catheter insertion was related with Gram-positive urosepsis. The antibiotic susceptibility among Gram-negative organisms was not different depending on the source of bacteremic UTI, while non-E. coli Gram-negative organisms were less frequently susceptible for cefotaxime, cefoperazone/sulbactam, and aztreonam. All-cause in-hospital mortality was 11.6%, and functional dependency (adjusted hazard ratio=HR=10.9, 95% confidence interval=95%CI=2.2-54.6) and low serum albumin (adjusted HR=27.0, 95%CI=2.0-361.2) were independently related with increased all-cause in-hospital mortality. Crown Copyright © 2010. Published by Elsevier Ireland Ltd. All rights reserved.

Identification of Aerobic Gram-Positive Bacilli by Use of Vitek MS

PubMed Central

Navas, Maria; Pincus, David H.; Wilkey, Kathy; Sercia, Linda; LaSalvia, Margaret; Wilson, Deborah; Procop, Gary W.

2014-01-01

The accuracy of Vitek MS mass spectrometric identifications was assessed for 206 clinically significant isolates of aerobic Gram-positive bacilli representing 20 genera and 38 species. The Vitek MS identifications were correct for 85% of the isolates (56.3% to the species level, 28.6% limited to the genus level), with misidentifications occurring for 7.3% of the isolates. PMID:24501030

Synthesis and Antimicrobial Activity of Some Novel Cross-Linked Chitosan Hydrogels

PubMed Central

Mohamed, Nadia Ahmed; Fahmy, Mona Mohamed

2012-01-01

Four novel hydrogels based on chitosan were synthesized via a cross-linking reaction of chitosan with different concentrations of oxalyl bis 4-(2,5-dioxo-2H-pyrrol- 1(5H)-yl)benzamide. Their structures were confirmed by fourier transform infrared X-ray (FTIR), scanning electron microscopy (SEM) and X-ray diffraction. The antimicrobial activities of the hydrogels against two crop-threatening pathogenic fungi namely: Aspergillus fumigatus (A. fumigatus, RCMBA 06002), and Aspergillus niger (A. niger, RCMBA 06106), and five bacterial species namely: Bacillis subtilis (B. subtilis, RCMBA 6005), Staphylococcus aureus (S. aureus, RCMBA 2004), Streptococcus pneumoniae (S. pneumonia, RCMB 000101) as Gram positive bacteria, and Salmonella typhimurium (S. typhimurium, RCMB 000104), and Escherichia coli (E. coli, RCMBA 5003) as Gram negative bacteria have been investigated. The prepared hydrogels showed much higher antimicrobial activities than that of the parent chitosan. The hydrogels were more potent in case of Gram-positive bacteria than Gram-negative bacteria. Increasing the degree of cross-linking in the hydrogels resulted in a weaker antimicrobial activity. PMID:23109847

Polymicrobial tenosynovitis with Pasteurella multocida and other Gram negative bacilli after a Siberian tiger bite

PubMed Central

Isotalo, P; Edgar, D; Toye, B

2000-01-01

Mammalian bites present a considerable clinical problem because they are often associated with bacterial infections. Pasteurella multocida is a microorganism that commonly infects both canine and small feline bites. Zoonotic infections developing after large feline bites have been recognised, although their reports are limited. We describe a 35 year old man who was bitten by a Siberian tiger and who developed infectious tenosynovitis secondary to P multocida, Bergeyella (Weeksella) zoohelcum, and Gram negative bacteria most like CDC group EF-4b and comamonas species. The latter three bacteria have not been isolated previously from large feline bite wounds. Key Words: animal bite • zoonotic infection • Pasteurella multocida • Bergeyella zoohelcum PMID:11127273

Automated reading of MIC microdilution trays containing fluorogenic enzyme substrates with the Sensititre Autoreader.

PubMed Central

Staneck, J L; Allen, S D; Harris, E E; Tilton, R C

1985-01-01

The Sensititre Autoreader is a microcomputer-driven instrument capable of automatically reading antimicrobial susceptibility microdilution trays. The instrument measures the fluorescence liberated by bacterial enzymatic activity on fluorogenic substrates as an indicator of growth in each well. A mathematical algorithm converts the fluorescent signals from an antimicrobial dilution series to an MIC endpoint. A three-center study evaluated the performance of the Autoreader in comparison with MIC determined visually in a duplicate set of control plates lacking fluorogenic substrate. Among 828 isolates of gram-negative bacilli tested against 17 antimicrobial agents, Autoreader 18-h MIC were within +/- 1 twofold dilution of control MIC values (agreement) in 95.3% of instances. In 3.5% of the instances, Autoreader values occurred +/- 2 half-step dilutions from control values (minor discrepancy), and in only 1.2% of instances did Autoreader values deviate from control values by greater than +/- 2 dilution steps (major discrepancy). Agreement, minor discrepancies, and major discrepancies were noted among 148 gram-positive cocci tested against 11 antimicrobial agents in 93.5, 4.8, and 1.7% of the instances, respectively. Over half of the major discrepancies noted with gram-negative bacilli occurred with Proteus mirabilis-beta-lactam combinations, a problem that was resolved when a lower initial inoculum was used. Inter-and intralaboratory reproducibility was excellent. Standard Sensititre susceptibility trays may be instrument read at 18 h reproducibly and accurately with only slight modification of conventional procedures to include fluorogenic enzyme substrates in the incubation broth. PMID:4031033

Bacteriological Assessment of Pneumonia Caused by Gram-Negative Bacteria in Patients Hospitalized in Intensive Care Unit.

PubMed

Guzek, A; Korzeniewski, K; Tomaszewski, D; Rybicki, Z; Zwolińska, E

2017-01-01

The article presents the results of 11-year study (2005-2015) of Gram-negative bacteria responsible for pneumonia in 2033 mechanically ventilated patients hospitalized in Intensive Care Unit. Of 8796 biological samples, consisting mainly of bronchial aspirate (97.9 %), 2056 bacterial strains were isolated and subjected to identification. VITEK 2 was used to determine drug susceptibility (classified according to the EUCAST criteria). ESBL, MBL and KPC-producing strains were identified by means of phenotypic methods using appropriate discs. The findings were that the predominant bacteria responsible for infections consisted of Enterobacteriaceae (42.0 %), Acinetobacter baumannii (37.2 %), Pseudomonas aeruginosa (16.1 %), and Stenotrophomonas maltophila (4.7 %). We observed a rise in the number of bacteria causing pneumonia throughout the study period, especially in S. maltophila and Enterobacteriaceae ESBL (+). Gram-negative bacilli were 100 % susceptible to colistin, apart from naturally resistant strains such as Proteus mirabilis, Serratia marcescens, whereas Enterobacteriaceae ESBL (+) were susceptible to imipenem and meropenem. Acinetobacter baumannii strains exhibited the lowest drug susceptibility. In conclusion, we report an increase in the prevalence of pneumonia associated with Gram-negative bacteria in mechanically ventilated intensive care patients. Colistin remains the most effective drug against the majority of Gram-negative bacteria. Therapeutic problems are common in the course of treatment of Acinetobacter baumannii infections.

Escherichia coli Isolated from Urinary Tract Infections of Lebanese Patients between 2005 and 2012: Epidemiology and Profiles of Resistance.

PubMed

Daoud, Ziad; Salem Sokhn, Elie; Masri, Khalil; Matar, Ghassan M; Doron, Shira

2015-01-01

The early treatment of urinary tract infections (UTIs) is directly related to decrease in morbidity, which makes the empirical treatment of great importance. Recently, beta lactamases of several types have emerged as significant mechanisms of resistance in Gram-negative bacilli, especially Escherichia coli. Our aim was to study the urinary E. coli isolated from Lebanese patients and to characterize their mechanisms of resistance. The study analyzed data between 2005 and 2012 of UTIs caused by E. coli. The mechanisms of resistance were characterized by phenotypic and genotypic methods and the pulsed-field gel electrophoresis (PFGE) was used to determine the different bacterial clusters. As expected, the highest incidence was observed with E. coli (60.53-73.98%) followed by K. pneumoniae (5.32-8.33%). ICU isolates were constantly associated with the lowest rates of susceptibility to extended-spectrum cephalosporins, ciprofloxacin, as well as most of the tested antibiotics. A 100% occurrence of CTX-M in extended-spectrum β-lactamase (ESBL)-producing isolates was recorded, followed by TEM, SHV, and OXA. In addition, 15.9% harbored 4 different ESBL enzymes and only 13 isolates (14.8%) harbored only one enzyme (CTX-M). Over the years, the simultaneous susceptibility of E. coli to ceftazidime and ciprofloxacin decreased from 62.5% in 2006 to 48.7% in 2012. PFGE results demonstrated that 10 clusters were 32 generated, denoting diversity among detected isolates. Understanding the epidemiology of resistance is 33 instrumental for the implementation of recommendations for the management of antimicrobials, infection 34 control measures, as well as active surveillance and antimicrobial stewardship.

Gram-negative urinary tract infections and increasing isolation of ESBL-producing or ceftazidime-resistant strains in children: results from a single-centre survey.

PubMed

Giardino, Stefano; Bandettini, Roberto; Perotti, Maddalena; Piaggio, Giorgio; Degl'Innocenti, Ludovica; Sacco, Rosanna; Ciucci, Antonella; Caviglia, Ilaria; Barabino, Paola; Ginocchio, Francesca; Losurdo, Giuseppe; Haupt, Riccardo; Castagnola, Elio

2013-03-01

Urinary tract infections (UTIs) are an important cause of morbidity in paediatrics, especially related to urinary tract malformation and neurogenic bladder dysfunction. The infection control team of Istituto Giannina Gaslini, Genova, Italy, performs a prospective survey on the epidemiology of UTI in children admitted in the hospital, and data are expressed as episodes/1000 days of hospital admission. From 2007 to 2011 there was an increase in the rate of Gram-negative UTIs, especially in the Nephrology Unit (from 11.63 to 27.48, r-coefficient 0.95, P minor 0.05), associated with an increase in infections due to ESBL-producing strains (from 0.54 to 2.55, r-coefficient 0.89, P 0.05). This study indicates that there is an increase in the rate of Gram-negative UTIs, also due to resistant strains. The cause may be multifactorial, but it is noteworthy that it has been mainly observed in a ward where low-dose, long-term administration of antibacterial prophylaxis in children with urinary malformations or neurogenic bladder dysfunction is routine. This phenomenon gives cause for concern and should be monitored carefully to avoid the risk of selecting resistant bacteria that have no therapeutic options.

Gram stain microbiological pattern of upper extremities suppuration at Baptist Medical Centre, Ogbomoso Nigeria: a fifteen month review.

PubMed

Oke, A J; Olaolorun, D A; Meier, D E; Tarpley, J L

2011-06-01

Sixty-eight (68) patients with serious upper extremity suppurative infections, presenting within a period of fifteen (15) months, were prospectively studied clinically, Gram stain of aspirates/pus were performed, specimen cultured, planted, and where indicated glucose levels and haemoglobin genotype determined. Half of the patients had hand infections. Staphylococcus aureus was isolated from thirty-nine (39) patients. Gram Negative bacilli, including Salmonella were more isolated from patients with diabetes mellitus or Hgb SS or SC. The Gram stain results correlated with the culture result 90%. When Gram Positive cocci were demonstrated in the primary microscopic examination, cultures were not mandatory. When no organism was demonstrated on primary Gram stain or the patient was diabetic or a sickler, cultures of the specimens were done. The Gram stain, well performed, remains a useful, inexpensive, technologically appropriate laboratory test for abetting decision making in patients with upper extremity suppurative infections. Organisms encountered in this study included: Staphylococcus aureus, Streptococcus pyogenes, Salmonella typhi, Proteus mirabilis, Pseudomonas aeruginosa, and Coliforms.

Diagnostic value and cost utility analysis for urine Gram stain and urine microscopic examination as screening tests for urinary tract infection.

PubMed

Wiwanitkit, Viroj; Udomsantisuk, Nibhond; Boonchalermvichian, Chaiyaporn

2005-06-01

The aim of this study was to evaluate the diagnostic properties of urine Gram stain and urine microscopic examination for screening for urinary tract infection (UTI), and to perform an additional cost utility analysis. This descriptive study was performed on 95 urine samples sent for urine culture to the Department of Microbiology, Faculty of Medicine, Chulalongkorn University. The first part of the study was to determine the diagnostic properties of two screening tests (urine Gram stain and urine microscopic examination). Urine culture was set as the gold standard and the results from both methods were compared to this. The second part of this study was to perform a cost utility analysis. The sensitivity of urine Gram stain was 96.2%, the specificity 93.0%, the positive predictive value 94.3% and the negative predictive value 95.2%. False positives occurred with a frequency of 7.0% and false negatives 3.8%. For the microscopic examination, the sensitivity was 65.4%, specificity 74.4%, positive predictive value 75.6% and negative predictive value 64.0%. False positives occurred with a frequency of 25.6% and false negatives 34.6%. Combining urine Gram stain and urine microscopic examination, the sensitivity was 98.1%, specificity 74.4%, positive predictive value 82.3% and negative predictive value 97.0%. False positives occurred with a frequency of 25.6% and false negatives 1.9%. However, the cost per utility of the combined method was higher than either urine microscopic examination or urine Gram stain alone. Urine Gram stain provided the lowest cost per utility. Economically, urine Gram stain is the proper screening tool for presumptive diagnosis of UTI.

Pseudoclavibacter otitis media in a 3-year-old boy with pulmonary and spinal tuberculosis.

PubMed

Ayuthaya, Satja Issaranggoon na; Leelaporn, Amornrut; Kiratisin, Pattarachai; Oberdorfer, Peninnah

2015-05-01

Pseudoclavibacter has rarely been documented as an etiologic agent of infection in humans. We presented the first case report of Pseudoclavibacter otitis media in a boy with pulmonary and spinal tuberculosis.A 3-year-old boy was referred to our hospital due to prolonged fever and progressive paraplegia for 3 months. He had yellowish discharge from both ear canals. The pleural fluid culture was positive for Mycobacterium tuberculosis. The discharge from both ears culture yielded yellow colonies of gram-positive bacilli with branching. This organism was positive for modified acid-fast bacilli stain but negative for acid-fast bacilli stain. Biochemical characteristics of this isolate were positive for catalase test but negative for oxidase, nitrate, esculin, and sugar utilization tests. The organism was further subjected to be identified by 16S ribosomal deoxyribonucleic acid gene sequencing. The result yielded Pseudoclavibacter species (99.4% identical), which could be most likely a potential pathogen in immunocompromised host like this patient. He responded well with intravenous trimetroprim-sulfamethoxazole for 6 weeks.This is the first case report of Pseudoclavibacter otitis media in children, and this case could emphasize Pseudoclavibacter species as a potential pathogen in immunocompromised host.

Pseudoclavibacter Otitis Media in a 3-Year-Old Boy With Pulmonary and Spinal Tuberculosis

PubMed Central

Ayuthaya, Satja Issaranggoon na; Leelaporn, Amornrut; Kiratisin, Pattarachai; Oberdorfer, Peninnah

2015-01-01

Abstract Pseudoclavibacter has rarely been documented as an etiologic agent of infection in humans. We presented the first case report of Pseudoclavibacter otitis media in a boy with pulmonary and spinal tuberculosis. A 3-year-old boy was referred to our hospital due to prolonged fever and progressive paraplegia for 3 months. He had yellowish discharge from both ear canals. The pleural fluid culture was positive for Mycobacterium tuberculosis. The discharge from both ears culture yielded yellow colonies of gram-positive bacilli with branching. This organism was positive for modified acid-fast bacilli stain but negative for acid-fast bacilli stain. Biochemical characteristics of this isolate were positive for catalase test but negative for oxidase, nitrate, esculin, and sugar utilization tests. The organism was further subjected to be identified by 16S ribosomal deoxyribonucleic acid gene sequencing. The result yielded Pseudoclavibacter species (99.4% identical), which could be most likely a potential pathogen in immunocompromised host like this patient. He responded well with intravenous trimetroprim-sulfamethoxazole for 6 weeks. This is the first case report of Pseudoclavibacter otitis media in children, and this case could emphasize Pseudoclavibacter species as a potential pathogen in immunocompromised host. PMID:25929901

Rapid detection of multidrug resistant Gram-negative bacilli by Cica-Beta-Test strips.

PubMed

Lavigne, J-P; Pfeiffer, C; Vidal, L; Sotto, A

2011-02-01

This study aimed to evaluate the sensitivity and specificity of a new system (Cica-Beta-Test, Kanto Chemical, Japan) for rapid detection of AmpC-derepressed, extended-spectrum β-lactamases (ESβL) and metallo-β-lactamases (MβL). Two hundred Multi-Drug Resistant (MDR)-Gram-negative bacilli were studied: 170 Enterobacteriaceae and 30 Gram-negative non-fermentative bacteria. One hundred and eighteen strains produced an ESβL, seven MβL and 75 derepressed cephalosporinases. One drop of substrate was dispensed onto the filter pad of the Cica-Beta-Test strip. The bacterial colonies were spread on the filter pad of strip. The reading was performed after 2 to 15 min: turning chromogenic indicated the positive test. Three tests were used: Cica-Beta I for detection of MDR bacteria; Cica-Beta MβL for detection of MβL-producing bacteria and Cica-Beta CVA, which distinguish ESβL and AmpC-derepressed producers. Results were compared with molecular assays. Cica-Beta-Test I has detected 194 MDR (sensitivity 97%), Cica-Beta-Test MβL has shown the presence of six MβL tested (sensitivity 85.7%). Five strains were non-MβL false positive (specificity 97.3%). Cica-Beta-Test CVA allowed the differentiation of ESβL-producing strains (109/115) and AmpC-derepressed strains (56/67) (sensitivity 94.8%, specificity 83.8%). Because of their epidemic nature, the MDR strains are screened and require strict hygienic measures patients. The simultaneous use of three strips can quickly determine the presence of MDR including ESβL and MβL. Rapid screening of MDR avoids transmission and limits the use of broad-spectrum antibiotics. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Increasing resistant coagulase negative staphylococci in bovine clinical mastitis.

PubMed

Moniri, R; Dastehgoli, K; Akramian, A

2007-08-01

The aim of this study was to determine Coagulase Negative Staphylococci (CNS) and other bacteria for their resistance to antimicrobial agents approved for the control of pathogens involved in clinical bovine mastitis. This descriptive study was done on 106 milk samples obtained from clinical mastitis in dairy cattle husbandry from April 2006 through August 2006 in Kashan, Iran. From the total of 106 milk samples collected from clinical mastitis, 96 (90.6%) lead to positive culture. Coagulase negative Staphylococci isolated in 51 out of 96 samples (53.1%), Staphylococcus aureus isolated in 21 out of 96 (21.9%), gram negative bacilli isolated in 14 out of 96 (14.6%) and Enterococci isolated in 4 (4.2%). The highest rate of resistant CNS observed to penicillin (56.6%) and the highest rate of sensitivity to enrofloxacin 100%, followed by kanamycin, streptomycin and neomycin, 92.2, 82.3 and 82.3%, respectively. The highest rate of resistance S. aureus exhibited to penicillin (66.6%); while the highest rate of sensitivity showed to trimethoprim-sulphamethoxasole (81%), followed by kanamycin and enrofloxacin both at 76.2%. The highest rate of resistance gram negative bacilli exhibited to ampicillin and erythromycin at 71.4%. Their highest rate of sensitivity observed to enrofloxacin (78.6%), followed by kanamycin, (71.4%). In recent years, CNS is emerging as important minor mastitis pathogens and can be the cause of substantial economic losses. The high resistance rate to penicillin and other antibiotics found in this study emphasize the importance of identification of CNS when a bovine clinical mastitis is present.

Epidemiology, susceptibility, and risk factors for acquisition of MDR/XDR Gram-negative bacteria among kidney transplant recipients with urinary tract infections.

PubMed

Yuan, Xiuhong; Liu, Taohua; Wu, Di; Wan, Qiquan

2018-01-01

Multiple drug resistant/extensively drug resistant (MDR/XDR) Gram-negative urinary tract infections (UTIs) represent a growing threat to kidney transplant recipients. This retrospective study aimed to assess the incidence and microbiological profile of MDR/XDR Gram-negative UTIs, to identify drug susceptibility of MDR/XDR bacteria, and to determine the potential risk factors for MDR/XDR UTIs in kidney recipients. During the study period, 1569 patients underwent consecutive kidney transplantation in two transplantation centers. We studied the demographics, clinical characteristics, and urine culture data from kidney recipients with MDR/XDR Gram-negative UTIs, and verified the risk factors associated with MDR/XDR infections. Eighty-one kidney recipients yielded 88 episodes of MDR/XDR Gram-negative UTIs with five patients (6.2%) succumbing to all-cause in-hospital mortality. The most frequently isolated bacterium was Escherichia coli (62.5%). Almost all MDR/XDR Gram-negative bacteria were resistant to first- and second-generation cephalosporin, and monocyclic beta-lactam. They were relatively sensitive to meropenem, amikacin, and tigecycline. As for the 12 XDR bacteria, all of them were resistant to meropenem and 25% of them were resistant to tigecycline. All XDR Acinetobacter baumannii and E. coli were susceptible to tigecycline. Nosocomial infection (odds ratio [OR] = 11.429, 95% CI = 1.311-99.625, P = 0.027) was the only independent predictor of MDR/XDR Gram-negative UTIs. Non-fermenting bacterial infection (OR = 20.161, 95% CI = 3.409-119.240, P = 0.001), polycystic kidney disease (OR = 39.871, 95% CI = 1.979-803.384, P = 0.016), and serum creatinine level > 1.5 mg/dL (OR = 8.688, 95% CI = 1.354-55.747, P = 0.023) were significantly different between XDR and MDR Gram-negative UTIs. Meropenem, amikacin, and/or tigecycline can be prescribed for MDR/XDR Gram-negative infections. Tigecycline can also be prescribed for XDR A. baumannii and E. coli . Nosocomial infection was a risk factor for MDR/XDR Gram-negative UTIs, while XDR UTIs were associated with non-fermenting bacterial infection, polycystic kidney disease, and impaired renal function.

Lack of clinical utility of urine gram stain for suspected urinary tract infection in pediatric patients.

PubMed

Cantey, Joseph B; Gaviria-Agudelo, Claudia; McElvania TeKippe, Erin; Doern, Christopher D

2015-04-01

Urinary tract infection (UTI) is one of the most common infections in children. Urine culture remains the gold standard for diagnosis, but the utility of urine Gram stain relative to urinalysis (UA) is unclear. We reviewed 312 pediatric patients with suspected UTI who had urine culture, UA, and urine Gram stain performed from a single urine specimen. UA was considered positive if ≥10 leukocytes per oil immersion field were seen or if either nitrates or leukocyte esterase testing was positive. Urine Gram stain was considered positive if any organisms were seen. Sensitivity, specificity, and positive and negative predictive values were calculated using urine culture as the gold standard. Thirty-seven (12%) patients had a culture-proven UTI. Compared to urine Gram stain, UA had equal sensitivity (97.3% versus 97.5%) and higher specificity (85% versus 74%). Empirical therapy was prescribed before the Gram stain result was known in 40 (49%) patients and after in 42 (51%) patients. The antibiotics chosen did not differ between the two groups (P=0.81), nor did they differ for patients with Gram-negative rods on urine Gram stain compared to those with Gram-positive cocci (P=0.67). From these data, we conclude that UA has excellent negative predictive value that is not enhanced by urine Gram stain and that antibiotic selection did not vary based on the urine Gram stain result. In conclusion, the clinical utility of urine Gram stain does not warrant the time or cost it requires. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Lack of Clinical Utility of Urine Gram Stain for Suspected Urinary Tract Infection in Pediatric Patients

PubMed Central

Gaviria-Agudelo, Claudia; McElvania TeKippe, Erin; Doern, Christopher D.

2015-01-01

Urinary tract infection (UTI) is one of the most common infections in children. Urine culture remains the gold standard for diagnosis, but the utility of urine Gram stain relative to urinalysis (UA) is unclear. We reviewed 312 pediatric patients with suspected UTI who had urine culture, UA, and urine Gram stain performed from a single urine specimen. UA was considered positive if ≥10 leukocytes per oil immersion field were seen or if either nitrates or leukocyte esterase testing was positive. Urine Gram stain was considered positive if any organisms were seen. Sensitivity, specificity, and positive and negative predictive values were calculated using urine culture as the gold standard. Thirty-seven (12%) patients had a culture-proven UTI. Compared to urine Gram stain, UA had equal sensitivity (97.3% versus 97.5%) and higher specificity (85% versus 74%). Empirical therapy was prescribed before the Gram stain result was known in 40 (49%) patients and after in 42 (51%) patients. The antibiotics chosen did not differ between the two groups (P = 0.81), nor did they differ for patients with Gram-negative rods on urine Gram stain compared to those with Gram-positive cocci (P = 0.67). From these data, we conclude that UA has excellent negative predictive value that is not enhanced by urine Gram stain and that antibiotic selection did not vary based on the urine Gram stain result. In conclusion, the clinical utility of urine Gram stain does not warrant the time or cost it requires. PMID:25653411

Bovine esophageal and glossal ulceration associated with Pseudomonas aeruginosa and Fusobacterium spp.in a 10-month-old Holstein heifer.

PubMed

Tosaki, Kaori; Kojima, Hirokazu; Akama, Shunsuke; Ootake, Yoshihiro; Inoue, Kyoichi; Katsuda, Ken; Shibahara, Tomoyuki

2018-05-25

An underweight 10-month-old Holstein heifer presented with anorexia and ananastasia and was euthanized. Postmortem examination revealed extensive ulceration in the esophagus, tongue, and omasum. Histopathological examination revealed severe necrotic esophagitis, glossitis, and omasitis. Many Gram-negative bacilli were detected throughout the necrotic area in the digestive tract; these were identified as Pseudomonas aeruginosa on the basis of isolation tests, molecular examinations, and immunohistochemistry. Gram-negative long filamentous organisms in the superficial layers of the necrotic lesions reacted positively with antibodies against Fusobacteriumnecrophorum subsp. necrophorum. Thus, the necrotic lesions were confirmed to be associated with P. aeruginosa and Fusobacterium spp. This is the first detection of P. aeruginosa in bovine esophageal and glossal ulcers associated with Fusobacterium spp.

Anaerobic infections in surgical wards: a two year study

PubMed Central

Ananth-Shenoy, Padmaja; Vishwanath, Shashidhar; Targain, Ryumzook; Shetty, Seema; Sunil-Rodrigues, Gabriel; Mukhopadhyay, Chiranjay; Chawla, Kiran

2016-01-01

Background and Objectives: Anaerobic bacteria are recognized as important pathogens in surgical infections. However, they are the most overlooked microorganisms by the clinic and the laboratory because of the tedious culture techniques with longer turn-around times. The study was aimed to analyze the frequency of anaerobic bacterial surgical infections and their predisposing factors. Materials and Methods: A retrospective study was conducted over a period of two years including patients with surgical infections. The specimens were processed by Gram staining, aerobic and anaerobic culture. The anaerobic bacteria were isolated using standard procedures. The predisposing factors and clinical presentation were studied in these patients. Results: A total of 261 specimens were received from patients with diverse infections from surgical wards. Ninety-one anaerobes were isolated from 64 (24.5%) surgical patients with a predominance of Gram-negative bacilli (37.4%). Anaerobic bacteria as monomicrobial isolates were seen in 21.9% isolates. Anaerobic bacterial isolation along with aerobic bacteria was seen in 71.9% of patients and polymicrobial anaerobic growth was detected in 6.3% of patients. Diabetes mellitus (28, 43.8%) was found to be the most frequent predisposing factor. Bacteroides fragilis group (20.9%) were the most frequent anaerobic Gram-negative bacilli followed by Prevotella spp. (12.1%). Peptostreptococcus anaerobius was the predominant anaerobic cocci isolated (14.3%). Necrotizing fascitis (34.4%) was the most common clinical presentation with anaerobic etiology followed by deep seated abscesses (23.4%). Conclusion: Anaerobic bacteria were isolated from a significant proportion of surgical infections. To avoid therapeutic failures, anaerobic bacteria in surgical infections need to be recognized by surgeons and laboratorians. PMID:27928485

Time-to-positivity, type of culture media and oxidase test performed on positive blood culture vials to predict Pseudomonas aeruginosa in patients with Gram-negative bacilli bacteraemia.

PubMed

Cobos-Triguero, N; Zboromyrska, Y; Morata, L; Alejo, I; De La Calle, C; Vergara, A; Cardozo, C; Arcas, M P; Soriano, A; Marco, F; Mensa, J; Almela, M; Martínez, J A

2017-02-01

The aim of this study was to determine the usefulness of oxidase test and time-to-positivity (TTP) in aerobic and anaerobic blood culture vials to detect the presence of Pseudomonas aeruginosa in patients with Gram-negative bacilli (GNB) bacteraemia. TTP was recorded for each aerobic and anaerobic blood culture vial of monomicrobial bacteraemia due to GNB. Oxidase test was performed in a pellet of the centrifuged content of the positive blood culture. An algorithm was developed in order to perform the oxidase test efficiently taking into account TTP and type of vial. A total of 341 episodes of GNB bacteraemia were analysed. Sensitivity, specificity, positive predictive value and negative predictive value of the oxidase test performed on positive vials with GNB to predict P. aeruginosa were 95%, 99%, 91%, and 99%, respectively. When growth was first or exclusively detected in anaerobic vials, P. aeruginosa was never identified hence the performance of the oxidase test could be avoided. When growth was only or first detected in aerobic vials, a TTP≥8h predicted P. aeruginosa in 37% or cases (63 of 169), therefore oxidase test is highly recommended. Oxidase test performed onto positive blood culture vials previously selected by TTP and type of vials is an easy and inexpensive way to predict P. aeruginosa. In most cases, this can lead to optimization of treatment in less than 24 hours.

[Bacterial culture and drug sensitivity analysis of upper urinary tract calculi complicating with infection].

PubMed

Wang, Shu; Shi, Yong-kang; Huang, Xiao-bo; Ma, Kai; Xu, Qing-quan; Xiong, Lin-lin; Li, Jian-xing; Wang, Xia-feng

2014-10-18

To investigate the bacteriology and drug sensitivity of upper urinary tract calculi patients, and to provide information for choosing suitable antibiotics. In the study, 21 patients who suffered from lithiasis in upper urinary tract and required an emergency drainage for acute obstruction and infection were the "acute group"; 64 patients with calculi in upper urinary tract and accompanied with no infectious symptoms were the "common group". The bacteriology and drug sensitivity of the two groups were investigated. Gram-negative bacteria infected the most common of upper urinary tract calculi patients with infection, accounting for 71.4% in the acute group and 65.7% in the common group, among which Escherichia coli were the predominant ones (35.7% in the acute group and 32.9% in the common group). No difference was found between these two groups in bacterial distribution (P>0.05). Although the average drug resistance rate of Gram-negative bacteria in the acute group was higher than that in the common group, it revealed no significant difference (P>0.05). The drug resistance rate to semisynthetic penicillin, cefuroxime and ceftriaxone were more than 50%, 60%, and 50%, respectively. Quinolones, such as ciprofloxacin and levofloxacin, got a 45% drug resistance. Aminoglycoside, carbapenema were sensitive to Gram-negative bacteria. Cefoperazone/sulbactam and piperacillin/tazobactam were more effective than ceftriaxone and piperacillin, respectively. There was no significant difference between upper urinary tract calculi patients with acute infection and common infection in bacteriology and drug sensitivity. Semisynthetic penicillin, the second generation of cephalosporin and quinolone were no longer the good choices of empirical use. Antibiotics combined with β-lactamase inhibitors would be an ideal empirical therapeutic choice.

Utility of Acridine Orange staining for detection of bacteria from positive blood cultures.

PubMed

Neeraja, M; Lakshmi, V; Padmasri, C; Padmaja, K

2017-08-01

The diagnostic performance of AO stain was evaluated for the detection of bacteria and or fungi from positive blood cultures. The sensitivity of Gram stain (GS) was 98.26% while Acridine Orange (AO) stain proved to be more sensitive (100%) with a Positive and Negative Predictive Value of 100% each. The specificity of both the stains was 100%. Overall agreement between the two stains was 98.23% (688/700). The organisms that were missed by GS and positive by AO were Candida species (Sutton, 2006) and Gram negative bacilli (GNB) (Sutton, 2006). Sensitivity of GS was 82.35% and AO was 100% among mixed cultures. Immediate reporting of the results of AO stain would have a significant impact on clinical management of patients with serious blood stream infections. Copyright © 2017 Elsevier B.V. All rights reserved.

In Vitro Activity of the Siderophore Cephalosporin, Cefiderocol, against a Recent Collection of Clinically Relevant Gram-Negative Bacilli from North America and Europe, Including Carbapenem-Nonsusceptible Isolates (SIDERO-WT-2014 Study).

PubMed

Hackel, Meredith A; Tsuji, Masakatsu; Yamano, Yoshinori; Echols, Roger; Karlowsky, James A; Sahm, Daniel F

2017-09-01

Cefiderocol (formerly S-649266) is an investigational siderophore cephalosporin. Iron-depleted cation-adjusted Mueller-Hinton broth (ID-CAMHB) was prepared according to the Clinical and Laboratory Standards Institute (CLSI) protocol and used to perform broth microdilution testing of cefiderocol against a 2014-2015 collection of clinical isolates of Gram-negative bacilli from North America ( n = 4,239) and Europe ( n = 4,966). The concentrations of cefiderocol inhibiting 90% of isolates tested (MIC 90 s) were 0.5 μg/ml (North America; n = 3,007) and 1 μg/ml (Europe; n = 3,080) for all isolates of Enterobacteriaceae ; 1 μg/ml (North America; n = 30) and 4 μg/ml (Europe; n = 139) for meropenem-nonsusceptible (MIC ≥ 2 μg/ml) isolates of Enterobacteriaceae ; 0.5 μg/ml for both North American ( n = 765) and European ( n = 765) isolates of Pseudomonas aeruginosa ; 0.5 μg/ml (North America; n = 151) and 1 μg/ml (Europe; n = 202) for meropenem-nonsusceptible (MIC ≥ 4 μg/ml) isolates of P. aeruginosa ; 1 μg/ml for both North American ( n = 309) and European ( n = 839) isolates of all Acinetobacter baumannii strains as well as for both North American ( n = 173) and European ( n = 595) isolates of meropenem-nonsusceptible A. baumannii ; and 0.5μg/ml (North America; n = 152) and 0.25 μg/ml (Europe; n = 276) for isolates of Stenotrophomonas maltophilia MICs of cefiderocol were ≤4 μg/ml for 99.9% (6,078/6,087) of all Enterobacteriaceae , 97.0% (164/169) of meropenem-nonsusceptible Enterobacteriaceae , 99.9% (1,529/1,530) of all P. aeruginosa isolates, 100% (353/353) of meropenem-nonsusceptible P. aeruginosa isolates, 97.6% (1,120/1,148) of all A. baumannii isolates, 96.9% (744/768) of meropenem-nonsusceptible A. baumannii isolates, 100% of isolates of S. maltophilia (428/428) and 93.8% of isolates of Burkholderia cepecia (11/12). We conclude that cefiderocol demonstrated potent in vitro activity against a recent collection of clinical isolates of commonly encountered Gram-negative bacilli, including carbapenem-nonsusceptible isolates. Copyright © 2017 American Society for Microbiology.

Fosfomycin: An Alternative Therapy for the Treatment of UTI Amidst Escalating Antimicrobial Resistance.

PubMed

Sabharwal, Ekadashi Rajni; Sharma, Rajni

2015-12-01

Urinary tract infections (UTIs) are the most commonly encountered infectious diseases. The current study was undertaken with a dual purpose, to provide an insight into the current scenario of the microorganisms causing UTI, their antimicrobial sensitivity patterns and also try and evaluate the activity of fosfomycin against E. coli, both ESBL producers as well as non-producers. The study was conducted prospectively in the Department of Microbiology of a tertiary care hospital from January to June 2014. A total of 358 isolates from the urinary samples of the patients with a diagnosis of urinary tract infection were included in the study. Antibiotic sensitivity testing and extended spectrum beta lactamase (ESBL) production testing was done as per CLSI guidelines. These represented 297 (82.9%) gram-negative isolates and 61 (17%) gram-positive isolates. The 297 gram-negative isolates represented 265 (89.2%) members of the Enterobacteriaceae, 185 (69.8%) of which were Escherichia coli, 66 (24.9%) Klebsiella spp. and 14 (5.28%) Proteus spp. Non-fermentative Pseudomonas spp were isolated from 8.9% cases. Amongst the Gram negative isolates tested, 78 (21.8%) formed extended spectrum beta-lactamases. Of the total 358 isolates tested, 338 (94.4%) were found to be susceptible to fosfomycin. Fosfomycin showed good activity against both ESBL-producing and ESBL-negative E. coli isolates. The main finding of our study is that fosfomycin exhibits excellent antimicrobial activity even against the isolates with relatively high levels of antimicrobial resistance and hence can be a useful drug in our armamentarium.

77 FR 11133 - Draft Guidance for Industry on Complicated Urinary Tract Infections: Developing Drugs for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-24

... abnormalities of the urinary tract, but are also considered to be a subset of cUTI. Different types of bacteria can cause cUTI, but Gram-negative bacteria are most often associated with cUTI. This draft guidance..., based on resolution of clinical symptoms and eradication of bacteria from the urinary tract, was derived...

Resistance among Gram-negative ESKAPE pathogens isolated from hospitalized patients with intra-abdominal and urinary tract infections in Latin American countries: SMART 2013-2015.

PubMed

Karlowsky, James A; Hoban, Daryl J; Hackel, Meredith A; Lob, Sibylle H; Sahm, Daniel F

Gram-negative ESKAPE pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are important etiologic agents of nosocomial infection that are frequently resistant to broad-spectrum antimicrobial agents. Gram-negative ESKAPE pathogens were collected from hospitalized patients in 11 Latin American countries from 2013 to 2015 as part of the Study for Monitoring Antimicrobial Resistance Trends (SMART) global surveillance program. In total, 2113 isolates from intra-abdominal infections (IAI) and 970 isolates from urinary tract infections (UTI) were tested against antimicrobial agents using standardized CLSI broth microdilution methodology. Of the agents tested, amikacin demonstrated the highest rates of susceptibility (%) for K. pneumoniae (92.2, 92.3), Enterobacter spp. (97.5, 92.1), and P. aeruginosa (85.3, 75.2) isolates from both IAI and UTI, respectively. Ertapenem (68.5, 62.6) and imipenem (79.2, 75.9) showed substantially higher rates of susceptibility (%) than other β-lactams, including piperacillin-tazobactam (35.9, 37.4) against ESBL-positive isolates of K. pneumoniae from IAI and UTI, respectively. Rates of susceptibility to all agents tested against A. baumannii were ≤30.9%. Gram-negative ESKAPE pathogens isolated from Latin America demonstrated compromised in vitro susceptibility to commonly prescribed broad-spectrum, parenteral antimicrobial agents. Continued surveillance is warranted. New antimicrobial agents with potent activity against Gram-negative ESKAPE pathogens are urgently needed. Copyright © 2017 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

Antibiotic susceptibility patterns of different bacteria isolated from patients with ventilator associated pneumonia (vap).

PubMed

Alqurashi, Abdulrahman M

2005-09-01

Ventilator associated pneumonia (VAP) is a frequent complication of mechanical ventilation (MV) and it is a leading cause of death in MV patients. The development of VAP has been demonstrated as being due to aspiration of oropharyngeal secretion, ventilator tubing condensate, or gastric contents that are colonized with pathogenic microorganisms. The aim of the present study is to isolate and identify bacteria that cause VAP and to study antibiotic susceptibility. This study was carried out on 95 patients who fulfilled the diagnostic criteria for VAP. Quantitative cultures of endotracheal aspirates (EA) using a cut-off point of 10(6) cfu/ml was done. The microbiological results revealed that gram negative bacilli were the most common bacterial agents responsible for VAP and accounted for 78.8% of all the causative agents. The most common isolated organisms were Klebsiella pnemouniae (30.9 %) followed by Pseudomonas aeruginosa (22.5%), Staphylococcus aureus (21.2%), Eschericia coli (12.8 %), Proteus spp. (9.8%), and Citrobacter spp. (2.8%). Blood cultures were positive in 25.9% of patients with Klebsiella pnemouniae in about 33.3%. From this study, it can be concluded that VAP is an important nosocomial infection. EA is a simple procedure to obtain respiratory samples and perform sensitivity testing in patients with VAP. Also, the commonest cause of VAP is gram negative bacilli.

Occurrence of bla genes encoding carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter baumannii from Intensive Care Unit in a tertiary care hospital.

PubMed

Subramaniyan, Jayanthi Siva; Sundaram, Jeya Meenakshi

2018-01-01

ICU shows increasing incidence of infection associated with the use of invasive procedures for the diagnostic purpose as well as the indiscriminate use of antibiotics. Pseudomonas aeruginosa and Acinetobacter species are "very successful" pathogen and the emergence of the Metallo-β-Lactamases (MBL) is becoming a therapeutic challenge. To isolate the Nonfermenting Gram negative bacilli from the ICU samples. To identify the metallo betalactamase producers and to detect the bla gene presence among the Pseudomonas aeruginosa and Acinetobacter baumannii . The Nonfermenting Gram negative bacilli isolates from the ICU samples were taken over for 5 years (2009-2014) in a tertiary care hospital. The isolates of Pseudomonas species and Acinetobacter species were confirmed by API analyser and processed according to standard procedures. Detection of the MBL producers were done by E strip method and subjected for bla gene detection by PCR method. In our study a total of 195 isolates of NFGNB were obtained from various ICU. Of these MBL producers, 26 % were Pseudomonas aeruginosa and 25 % were Acinetobacter baumannii . The subtypes of bla VIM MBL producing P.aeruginosa were 26%. The predominant gene coding for MBL activity in A.baumannii were found to be bla OXA gene 11.9%. The gene accession numbers were KF975367, KF975372. We have to control the development and dissemination of these superbugs among the ICU's.

The Challenging Diagnosis of Non-Community-Acquired Pneumonia in Non-Mechanically Ventilated Subjects: Value of Microbiological Investigation.

PubMed

Messika, Jonathan; Stoclin, Annabelle; Bouvard, Eric; Fulgencio, Jean-Pierre; Ridel, Christophe; Muresan, Ioan-Paul; Boffa, Jean-Jacques; Bachmeyer, Claude; Denis, Michel; Gounant, Valérie; Esteso, Adoracion; Loi, Valeria; Verdet, Charlotte; Prigent, Hélène; Parrot, Antoine; Fartoukh, Muriel

2016-02-01

Early recognition and an attempt at obtaining microbiological documentation are recommended in patients with non-community-acquired pneumonia (NCAP), whether hospital-acquired (HAP) or health care-associated (HCAP). We aimed to characterize the clinical features and microbial etiologies of NCAP to assess the impact of microbiological investigation on their management. This was a prospective 1-y study in a university hospital with 141 non-mechanically ventilated subjects suspected of having HAP (n = 110) or HCAP (n = 31). Clinical criteria alone poorly identified pneumonia (misdiagnosis in 50% of cases). Microbiological confirmation was achievable in 80 subjects (57%). Among 79 microorganisms isolated, 28 were multidrug-resistant aerobic Gram-negative bacilli and group III Enterobacteriaceae and 6 were methicillin-resistant Staphylococcus aureus. Multidrug-resistant aerobic Gram-negative bacilli accounted for one third of the microorganisms in early-onset HAP and for 50% in late-onset HAP. Methicillin-resistant S. aureus was most often recovered from subjects with HCAP. Inappropriate empirical antibiotics were administered to 36% of subjects with confirmed pneumonia. Forty subjects were admitted to the ICU, 13 (33%) of whom died. Overall, 39 subjects (28%) died in the hospital. Integrating the microbiological investigation in the complex clinical diagnostic workup of patients suspected of having NCAP is mandatory. Respiratory tract specimens should be obtained whenever possible for appropriate management. Copyright © 2016 by Daedalus Enterprises.

Misinterpretation of Gram Stain from the Stationary Growth Phase of Positive Blood Cultures for Brucella and Acinetobacter Species.

PubMed

Bazzi, Ali M; Al-Tawfiq, Jaffar A; Rabaan, Ali A

2017-01-01

Acinetobacter baumannii and Brucella species are Gram-negative organisms that are vulnerable to misinterpretation as Gram-positive or Gram-variable in blood cultures. We assess the random errors in gram stain interpretation to reduce the likelihood of such errors and therefore patient harm. Aerobic and anaerobic blood cultures from two patients in an acute care facility in Saudi Arabia were subjected to preliminary Gram-staining. In case 1, VITEK-2 Anaerobe Identification, repeat Gram staining from a blood agar plate, Remel BactiDrop™ Oxidase test, Urea Agar urease test and real-time PCR were used to confirm presence of Brucella and absence of Coryneform species. In case 2, repeat Gram- staining from the plate and the vials, VITEK-2 Gram-Negative Identification, real-time PCR and subculture on to Columbia agar, blood agar, and MacConkey agar were carried out to identify A. baumannii . In case 1, initially pleomorphic Gram-positive bacteria were identified. Coryneform species were suspected. Tiny growth was observed after 24 h on blood agar plates, and good growth by 48 h. Presence of Brucella species was ultimately confirmed. In case 2, preliminary Gram-stain results suggested giant Gram-positive oval cocci. Further testing over 18-24 h identified A. baumannii . Oxidase test from the plate and urease test from the culture vial is recommended after apparent identification of pleomorphic Gram-positive bacilli from blood culture, once tiny growth is observed, to distinguish Brucella from Corynebacterium species. If giant Gram-positive oval cocci are indicated by preliminary Gram-staining, it is recommended that the Gram stain be repeated from the plate after 4-6 h, or culture should be tested in Triple Sugar Iron (TSI) medium and the Gram stain repeated after 2-4 h incubation.

Antibacterial metabolites synthesized by psychrotrophic bacteria isolated from cold-freshwater environments.

PubMed

Barros, Javier; Becerra, José; González, Carlos; Martínez, Miguel

2013-03-01

The ability of three psychrotrophic Gram-negative bacilli isolated from Chilean Patagonian cold freshwater rivers to produce bioactive metabolites was evaluated. The strains were isolated from cold waters rivers and identified by their biochemical properties and 16S rRNA gene analysis. The metabolites fractions showing antibacterial activity were obtained by solvent extraction and partially characterized by gas-mass chromatography (GC-MS). Antibacterial activity of the fractions was evaluated by an agar-well diffusion test upon 14 bacterial strains, both Gram positive and Gram negative. Thermal and proteolytic resistances of the antibacterial metabolites fractions were also evaluated. Molecular analysis allows the identification of the three Patagonian strains as Pseudomonas sp. RG-6 (Pseudomonas brenneri 99.6 % identity), Pseudomonas sp. RG-8 (Pseudomonas trivialis 99.6 % identity) and Yersinia sp. RP-3 (Yersinia aldovae 99.5 % identity). These extracts were able to inhibit both Gram-positive and Gram-negative bacteria but not Listeria monocytogenes. The antibacterial activity of the filtrated supernatants was lost at temperatures ≥60 °C, and was not affected by proteinase K treatment. The chemical structure of the active molecule remains to be elucidated, although the GC-MS analysis of the filtrates suggests that compounds like sesquiterpenes derivatives from β-maaliene or δ-selinene could be responsible of this antibacterial activity. Pristine cold freshwater streams showed to be interesting sources of metabolites-producing microorganisms with antibacterial activity.

Evaluation of the antibacterial potential of Petroselinum crispum and Rosmarinus officinalis against bacteria that cause urinary tract infections

PubMed Central

Petrolini, Fernanda Villas Boas; Lucarini, Rodrigo; de Souza, Maria Gorete Mendes; Pires, Regina Helena; Cunha, Wilson Roberto; Martins, Carlos Henrique Gomes

2013-01-01

In this study we evaluated the antibacterial activity of the crude hydroalcoholic extracts, fractions, and compounds of two plant species, namely Rosmarinus officinalis and Petroselinum crispum, against the bacteria that cause urinary tract infection. The microdilution method was used for determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The crude hydroalcoholic extract of R. officinalis displayed in vitro activity against Gram-positive bacteria, with satisfactory MBC for the clinical isolate S. saprophyticus. The fractions and the pure compound rosmarinic acid did not furnish promising results for Gram-negative bacteria, whereas fractions 2, 3, and 4 gave encouraging results for Gram-positive bacteria and acted as bactericide against S. epidermidis as well as E. faecalis (ATCC 29212) and its clinical isolate. R. officinalis led to promising results in the case of Gram-positive bacteria, resulting in a considerable interest in the development of reliable alternatives for the treatment of urinary infections. PMID:24516424

Evaluation of the antibacterial potential of Petroselinum crispum and Rosmarinus officinalis against bacteria that cause urinary tract infections.

PubMed

Petrolini, Fernanda Villas Boas; Lucarini, Rodrigo; de Souza, Maria Gorete Mendes; Pires, Regina Helena; Cunha, Wilson Roberto; Martins, Carlos Henrique Gomes

2013-01-01

In this study we evaluated the antibacterial activity of the crude hydroalcoholic extracts, fractions, and compounds of two plant species, namely Rosmarinus officinalis and Petroselinum crispum, against the bacteria that cause urinary tract infection. The microdilution method was used for determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The crude hydroalcoholic extract of R. officinalis displayed in vitro activity against Gram-positive bacteria, with satisfactory MBC for the clinical isolate S. saprophyticus. The fractions and the pure compound rosmarinic acid did not furnish promising results for Gram-negative bacteria, whereas fractions 2, 3, and 4 gave encouraging results for Gram-positive bacteria and acted as bactericide against S. epidermidis as well as E. faecalis (ATCC 29212) and its clinical isolate. R. officinalis led to promising results in the case of Gram-positive bacteria, resulting in a considerable interest in the development of reliable alternatives for the treatment of urinary infections.

Enteric gram-negative bacilli bloodstream infections: 17 years' experience in a neonatal intensive care unit.

PubMed

Cordero, Leandro; Rau, Rachel; Taylor, David; Ayers, Leona W

2004-06-01

To assess the occurrence of enteric gram-negative bacilli (EGNB) bloodstream infections (BSI) in a neonatal intensive care setting during a 17-year period in which a consistent antibiotic treatment program was in place. To document infections, outbreaks, or epidemics, emergence of antibiotic resistance, clinical correlates, and outcomes of the most prevalent EGNB (Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae). This study analyzed demographic, clinical, and bacteriologic information from 360 infants born 1986-2002 who developed 633 blood culture-proven BSI. A total of 121 EGNB were isolated (E coli, K pneumoniae, and E cloacae). Early-onset BSI were discovered within 48 hours from birth, and late-onset BSI were those that occurred thereafter. Suspected early-onset BSI were treated with ampicillin and gentamicin, suspected late-onset BSI with vancomycin and gentamicin. Antibiotics were changed on the basis of organism antimicrobial susceptibility. Early-onset BSI were noted in 52 of 21,336 (244/100,000) live births (1986-1991), 40 of 20,402 (196/100,000) live births (1992-1997), and 25 of 17,926 (139/100,000) live births (1998-2002). Of these cases, 39 were caused by E coli and 4 by K pneumoniae. Antibiograms for E coli isolated during the last 5 years of the study showed an increase in antibiotic resistance that coincided with obstetric group B streptococcus antepartum antibiotic prophylaxis. Group B streptococcus declined from 41 to 4 cases from the first to the last period. Late-onset BSI increased from 111 to 230 cases from the first to the second 6-year study period and declined modestly (171 cases) during the last. Fifteen percent (78 cases) of late-onset BSI were caused by EGNB, 5% by other gram-negative bacilli, 67% primarily by coagulase-negative staphylococcus, and 13% by fungus. Nonspecific clinical and hematologic signs of late-onset BSI were similar across EGNB species, but necrotizing enterocolitis was often associated with E coli, whereas pneumonia and prolonged thrombocytopenia characterized K pneumoniae infections. No outbreaks or epidemics were observed, and strains of EGNB with evidence of extended spectrum beta-lactamase production were never isolated. Antepartum antibiotic prophylaxis may have increased antibiotic resistance in E coli isolates from early-onset BSI but has dramatically decreased group B streptococcus infections. Late-onset BSI caused by EGNB increased, but without changes in antibiotic susceptibility. In spite of medical advances, E coli, K pneumoniae, and E cloacae remain responsible for significant morbidity and mortality, especially in very low birth weight infants.

Comparison of methods for the identification of microorganisms isolated from blood cultures.

PubMed

Monteiro, Aydir Cecília Marinho; Fortaleza, Carlos Magno Castelo Branco; Ferreira, Adriano Martison; Cavalcante, Ricardo de Souza; Mondelli, Alessandro Lia; Bagagli, Eduardo; da Cunha, Maria de Lourdes Ribeiro de Souza

2016-08-05

Bloodstream infections are responsible for thousands of deaths each year. The rapid identification of the microorganisms causing these infections permits correct therapeutic management that will improve the prognosis of the patient. In an attempt to reduce the time spent on this step, microorganism identification devices have been developed, including the VITEK(®) 2 system, which is currently used in routine clinical microbiology laboratories. This study evaluated the accuracy of the VITEK(®) 2 system in the identification of 400 microorganisms isolated from blood cultures and compared the results to those obtained with conventional phenotypic and genotypic methods. In parallel to the phenotypic identification methods, the DNA of these microorganisms was extracted directly from the blood culture bottles for genotypic identification by the polymerase chain reaction (PCR) and DNA sequencing. The automated VITEK(®) 2 system correctly identified 94.7 % (379/400) of the isolates. The YST and GN cards resulted in 100 % correct identifications of yeasts (15/15) and Gram-negative bacilli (165/165), respectively. The GP card correctly identified 92.6 % (199/215) of Gram-positive cocci, while the ANC card was unable to correctly identify any Gram-positive bacilli (0/5). The performance of the VITEK(®) 2 system was considered acceptable and statistical analysis showed that the system is a suitable option for routine clinical microbiology laboratories to identify different microorganisms.

Assessment of airborne bacteria in selected occupational environments in Quezon City, Philippines.

PubMed

Rendon, Rhoshela Vi C; Garcia, Bea Clarise B; Vital, Pierangeli G

2017-05-04

Exposure to bioaerosols has been associated with health deterioration among workers in several occupational environments. This highlights the need to study the microbiological quality of air of workplaces as no such study has been conducted yet in the Philippines. To detect and characterize the culturable mesophilic airborne bacteria in selected occupational environments we used passive sedimentation technique. It was observed that the number of colony-forming units was highest in junk shop, followed by the light railway transit station and last the office. By contrast, the bacterial composition was similar in all sites: Gram-positive cocci > Gram-positive bacilli > Gram-negative bacteria. Staphylococcus aureus and Bacillus spp. were also detected in all sites. These findings suggest that the presence of airborne bacteria may be a potential health hazard in urban occupational environments in the Philippines.

Athlete's foot caused by pseudomonas aeruginosa.

PubMed

Abramson, C

1983-01-01

An enzymatically active pigment-producing clinical isolate of Pseudomonas aeruginosa was found to produce a diffusible antifungal product that was shown to be inhibitory to the growth of several dermatophytes, specifically, Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum, and Microsporum audouini. In this study, Trichophyton rubrum was used as the test organism. The antifungal product was partially purified by Sephadex column chromatography and was found to be stable at 5 degrees, 25 degrees, and 37 degrees C. Several investigators have alluded to the fact that as asymptomatic cases of dermatophytosis simplex progress to symptomatic dermatophytosis complex, the bacterial profile changes from a gram-positive bacterial ecosystem to a gram-negative bacterial over-growth. The primary event in the pathogenesis of interdigital athlete's foot is the invasion of the horny layer by dermatophytes. This presents as a mild to moderate scaly lesion and is asymptomatic. As a result of predisposing factors, such as hyperhidrosis, occlusion by tight shoes, minute abrasions due to friction, and fungal-infected skin surfaces, dynamic overgrowth of opportunistic gram-negative bacilli prevails. As the gram-negative population increases, the recovery of dermatophytes dramatically diminishes, until a point is reached when no dermatophytes can be recovered from clinically symptomatic tinea pedis. Pseudomonas aeruginosa is inhibiting its fungal competitor Trichophyton rubrum by producing a diffusible antifungal agent into the infectious environment of the intertriginous foot lesion. Clinically, the patient is diagnosed as having tinea pedis; laboratory culture for fungus and KOH are negative, and what was a paradox just a few years ago can currently be identified and treated appropriately as gram-negative athlete's foot.

Screening of nursing home residents for colonization with carbapenem-resistant Enterobacteriaceae admitted to acute care hospitals: Incidence and risk factors.

PubMed

Cunha, Cheston B; Kassakian, Steven Z; Chan, Ryan; Tenover, Fred C; Ziakas, Panos; Chapin, Kimberle C; Mermel, Leonard A

2016-02-01

There are increasing reports of multidrug-resistant gram-negative bacilli in nursing homes and acute care hospitals. We performed a point prevalence survey to detect fecal carriage of gram-negative bacteria carrying carbapenem resistance genes or which were otherwise resistant to carbapenem antibiotics among 500 consecutive admissions from local nursing homes to 2 hospitals in Providence, Rhode Island. We performed a case-control study to identify risk factors associated with carriage of carbapenem-resistant Enterobacteriaceae (CRE). There were 404 patients with 500 hospital admissions during which they had rectal swab samples cultured. Fecal carriage of any carbapenem-resistant or carbapenemase- producing gram-negative bacteria was found in 23 (4.6%) of the 500 hospital admissions, including 7 CRE (1.4%), 2 (0.4%) of which were Klebsiella pneumoniae carbapenemase (ie, blaKPC) producing (CPE) Citrobacter freundii, 1 of which was carbapenem susceptible by standard testing methods. Use of a gastrostomy tube was associated with CRE carriage (P = .04). We demonstrated fecal carriage of carbapenem-resistant or carbapenemase-producing gram-negative bacteria in 4.6% of nursing home patients admitted to 2 acute care hospitals, but only 0.4% of such admissions were patients with fecal carriage of CPE. Use of gastrostomy tubes was associated with fecal carriage of gram-negative bacteria with detectable carbapenem resistance. CRE fecal carriage is uncommon in our hospital admissions from nursing homes. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Antimicrobial susceptibility of clinically isolated anaerobic bacteria in a University Hospital Centre Split, Croatia in 2013.

PubMed

Novak, Anita; Rubic, Zana; Dogas, Varja; Goic-Barisic, Ivana; Radic, Marina; Tonkic, Marija

2015-02-01

Anaerobic bacteria play a significant role in many endogenous polymicrobial infections. Since antimicrobial resistance among anaerobes has increased worldwide, it is useful to provide local susceptibility data to guide empirical therapy. The present study reports recent data on the susceptibility of clinically relevant anaerobes in a University Hospital Centre (UHC) Split, Croatia. A total of 63 Gram-negative and 59 Gram-positive anaerobic clinical isolates from various body sites were consecutively collected from January to December 2013. Antimicrobial susceptibility testing was performed using standardized methods and interpreted using EUCAST criteria. Patient's clinical and demographic data were recorded by clinical microbiologist. Among 35 isolates of Bacteroides spp., 97.1% were resistant to penicillin (PCN), 5.7% to amoxicillin/clavulanic acid (AMC), 8.6% to piperacillin/tazobactam (TZP), 29.0% to clindamycin (CLI) and 2.9% to metronidazole (MZ). Percentages of susceptible strains to imipenem (IPM), meropenem (MEM) and ertapenem (ETP) were 94.3. Resistance of other Gram-negative bacilli was 76.0% to PCN, 8.0% to AMC, 12.0% to TZP, 28.0% to CLI and 8% to MZ. All other Gram-negative strains were fully susceptible to MEM and ETP, while 96.0% were susceptible to IPM. Clostridium spp. isolates were 100% susceptible to all tested antibiotics except to CLI (two of four tested isolates were resistant). Propionibacterium spp. showed resistance to CLI in 4.3%, while 100% were resistant to MZ. Among other Gram-positive bacilli, 18.2% were resistant to PCN, 9.1% to CLI and 54.5% to MZ, while 81.8% of isolates were susceptible to carbapenems. Gram-positive cocci were 100% susceptible to all tested antimicrobials except to MZ, where 28.6% of resistant strains were recorded. Abdomen was the most common source of isolates (82.5%). The most prevalent types of infection were abscess (22.1%), sepsis (14.8%), appendicitis (13.9%) and peritonitis (6.6%). Twenty four patients (19.7%) received empiric antimicrobial therapy. One hundred and one patients (82.8%) had polymicrobial aerobic/anaerobic isolates cultivated from the same specimens. Almost all aerobic bacteria were of endogenous origin and showed fully susceptible antimicrobial profile; only 8.7% (9/104) were multiresistant and considered as hospital acquired. Based on our findings, β-lactam/β-lactamase inhibitor combinations and metronidazole remain useful antimicrobials for empiric treatment of anaerobic infections, while carbapenems should be reserved for situations were multidrug resistant, aerobic or facultative Gram-negative bacteria are expected. However, a certain percentage of resistant isolates were observed for each of these agents. Therefore, periodic resistance surveillance in anaerobes is highly recommended in order to guide empirical therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identification and Susceptibility Testing of Enterobacteriaceae and Pseudomonas aeruginosa by Direct Inoculation from Positive BACTEC Blood Culture Bottles into Vitek 2

PubMed Central

Bruins, Marjan J.; Bloembergen, Peter; Ruijs, Gijs J. H. M.; Wolfhagen, Maurice J. H. M.

2004-01-01

Inoculation of an automated system for rapid identification (ID) and antimicrobial susceptibility testing (AST) directly from positive blood culture bottles will reduce the turnaround time of laboratory diagnosis of septicemic patients, which benefits clinical outcome and decreases patient costs. Direct test results, however, must always be confirmed by testing a pure overnight culture, which is the “gold standard.” We studied the accuracy of direct testing versus repeat testing in order to investigate the possibility of refraining from repeat testing. We also assessed the clinical risk of reporting results based on direct testing only. We inoculated Vitek 2 (bioMérieux) directly from 410 positive BACTEC 9240 (BD) blood culture bottles containing gram-negative rods and studied the ID and AST results. In a comparison of direct inoculation with the standard method, a total of 344 isolates of Enterobacteriaceae and Pseudomonas aeruginosa were tested, and 93.0% were correctly identified. Of the 39 (10.2%) samples that contained bacilli not identifiable by Vitek 2, only 1 gave a conclusive, correct result. The overall MIC agreement among 312 isolates was 99.2%, with 0.8% very major and 0.02% major error rates. Of only three (polymicrobial) samples, the direct susceptibility pattern would be reported to the clinician as too sensitive. Vitek 2 results obtained from direct inoculation of blood culture bottles containing gram-negative bacilli are safe enough for immediate reporting, provided that ID and AST are consistent. Repeat testing is not necessary, unless Gram stain or overnight subculture results raise doubt about the purity of the culture. PMID:14715724

The abundance and diversity of heterotrophic bacteria as a function of harvesting frequency of duckweed (Lemna minor L.) in recirculating aquaculture systems.

PubMed

Ardiansyah, A; Fotedar, R

2016-07-01

Duckweed (Lemna minor L.) is a potential biofilter for nutrient removal and acts as a substrate for heterotrophic bacteria in recirculating aquaculture systems (RAS). Here, we determined the effects of harvesting frequency of duckweed on heterotrophic bacteria in RAS. Twelve independent RAS consisting of fish-rearing tank, biofilter tank and waste-collection tank were used to study the interactions between duckweed harvest frequencies up to 6 days and the composition, abundance and diversity of heterotrophic bacteria. After 36 days, heterotrophic bacteria in the biofilter tank were primarily Gram-negative cocci or ovoid, coccobacilli, Gram-negative bacilli and Gram-positive bacilli. Most bacterial genera were Bacillus and Pseudomonas while the least common was Acinetobacter. Duckweed harvested after every 2 days produced the highest specific growth rates (SGR) and total harvested biomass of duckweed, but harboured less abundant bacteria, whereas 6-day harvests had a higher growth index (GI) of duckweed than 2-day harvests, but caused a poor relationship between SGR and biomass harvest with the abundance and diversity of heterotrophic bacteria. Stronger correlations (R(2)  > 0·65) between duckweed SGR and biomass harvest with the heterotrophic bacteria diversity were observed at 4-day harvest frequency and the control. This study provides significant information on the interaction between the harvest frequency of duckweed and the composition, abundance and diversity of heterotrophic bacteria in recirculating aquaculture systems (RAS). Different harvest frequencies significantly influence the abundance and diversity of heterotrophic bacteria, which in turn may influence the nitrogen uptake efficiency of the system. The research is useful in improving the efficiency of removing nitrogenous metabolites in RAS directly by the duckweed and associated heterotrophic bacteria. © 2016 The Society for Applied Microbiology.

Microbiological Etiologies of Pneumonia Complicating Stroke: A Systematic Review.

PubMed

Kishore, Amit K; Vail, Andy; Jeans, Adam R; Chamorro, Angel; Di Napoli, Mario; Kalra, Lalit; Langhorne, Peter; Roffe, Christine; Westendorp, Willeke; Nederkoorn, Paul J; Garau, Javier; van de Beek, Diederik; Montaner, Joan; Woodhead, Mark; Meisel, Andreas; Smith, Craig J

2018-06-18

Identifying the causal pathogens of pneumonia complicating stroke is challenging, and antibiotics used are often broad spectrum, without recourse to the microbiological cause. We aimed to review existing literature to identify organisms responsible for pneumonia complicating stroke, before developing a consensus-based approach to antibiotic treatment. A systematic literature review of multiple electronic databases using predefined search criteria was undertaken, in accordance with Cochrane and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidance. Published studies of hospitalized adults with ischemic stroke, intracerebral hemorrhage, or both, which identified microbiological etiologies for pneumonia complicating stroke up to January 1, 2017, were considered. Analysis included summary statistics and random-effects meta-analysis where appropriate. Fifteen studies (40% ischemic stroke, 60% ischemic stroke and intracerebral hemorrhage) involving 7968 patients were included. Reported occurrence of pneumonia varied considerably between studies (2%-63%) with a pooled frequency of 23% (95% confidence interval, 14%-34%; I 2 =99%). Where reported (60%), the majority of pneumonia occurred within 1 week of stroke (78%). Reported frequency of positive culture data (15%-88%) varied widely. When isolated, aerobic Gram-negative bacilli (38%) and Gram-positive cocci (16%) were most frequently cultured; commonly isolated organisms included Enterobacteriaceae (21.8%: Klebsiella pneumoniae , 12.8% and Escherichia coli, 9%), Staphylococcus aureus (10.1%), Pseudomonas aeruginosa (6%), Acinetobacter baumanii (4.6%), and Streptococcus pneumoniae (3.5%). Sputum was most commonly used to identify pathogens, in isolation (40%) or in conjunction with tracheal aspirate (15%) or blood culture (20%). Although the analysis was limited by small and heterogeneous study populations, limiting determination of microbiological causality, this review suggests aerobic Gram-negative bacilli and Gram-positive cocci are frequently associated with pneumonia complicating stroke. This supports the need for appropriately designed studies to determine microbial cause and a consensus-based approach in antibiotic usage and further targeted antibiotic treatment trials for enhanced antibiotic stewardship. © 2018 American Heart Association, Inc.

Late-onset neonatal sepsis: recent developments

PubMed Central

Dong, Ying; Speer, Christian P

2015-01-01

The incidence of neonatal late-onset sepsis (LOS) is inversely related to the degree of maturity and varies geographically from 0.61% to 14.2% among hospitalised newborns. Epidemiological data on very low birth weight infants shows that the predominant pathogens of neonatal LOS are coagulase-negative staphylococci, followed by Gram-negative bacilli and fungi. Due to the difficulties in a prompt diagnosis of LOS and LOS-associated high risk of mortality and long-term neurodevelopmental sequelae, empirical antibiotic treatment is initiated on suspicion of LOS. However, empirical therapy is often inappropriately used with unnecessary broad-spectrum antibiotics and a prolonged duration of treatment. The increasing number of multidrug-resistant Gram-negative micro-organisms in neonatal intensive care units (NICU) worldwide is a serious concern, which requires thorough and efficient surveillance strategies and appropriate treatment regimens. Immunological strategies for preventing neonatal LOS are not supported by current evidence, and approaches, such as a strict hygiene protocol and the minimisation of invasive procedures in NICUs represent the cornerstone to reduce the burden of neonatal LOS. PMID:25425653

Diagnosis and treatment of bacterial prostatitis.

PubMed

Videčnik Zorman, Jerneja; Matičič, Mojca; Jeverica, Samo; Smrkolj, Tomaž

2015-01-01

Prostate inflammation is a common syndrome, especially in men under 50. It usually presents with voiding symptoms and pain in the genitourinary area, and sometimes as sexual dysfunction. Based on clinical and laboratory characteristics, prostatitis is classified as acute bacterial prostatitis, chronic bacterial prostatitis, chronic inflammatory and non-inflammatory prostatitis or chronic pelvic pain syndrome, and asymptomatic inflammatory prostatitis. Bacterial prostatitis is most often caused by infection with uropathogens, mainly Gram-negative bacilli, but Gram-positive and atypical microorganisms have also been identified as causative organisms of chronic prostatitis. According to reports by several authors, Chlamydia trachomatis and Trichomonas vaginalis are some of the most common pathogens, making chronic prostatitis a sexually transmitted disease. Diagnosis and treatment of acute and chronic bacterial prostatitis in particular can be challenging.

THE OCCURRENCE OF POLYGLYCEROPHOSPHATE AS AN ANTIGENIC COMPONENT OF VARIOUS GRAM-POSITIVE BACTERIAL SPECIES

PubMed Central

McCarty, Maclyn

1959-01-01

A bacterial substance has been described which gives a precipitin reaction with certain antisera to Group A streptococci. The precipitating antigen is present in various Gram-positive bacteria, including most hemolytic streptococci, staphylococci, and aerobic sporulating bacilli. It is not present in any of the Gram-negative species examined or in pneumococci, clostridia, or corynebacteria. Analysis of purified preparations obtained from Group A streptococci indicates that the antigen is a simple polymer of glycerophosphate. The identification has been confirmed by immunochemical studies, including precipitin tests and specific inhibition with synthetic polyglycerophosphates. In addition, the infrared spectra of bacterial and synthetic polyglycerophosphate are shown to be closely similar. Immunochemical analysis suggests that the amount of polyglycerophosphate present in Group A streptococci and staphylococci is approximately 1 per cent of the dry weight of the cells. The cellular localization and function of the polyglycerophosphate have not been established. PMID:13641562

Identification of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa in Blood Cultures: a Multicenter Performance Evaluation of a Three-Color Peptide Nucleic Acid Fluorescence In Situ Hybridization Assay▿

PubMed Central

Della-Latta, Phyllis; Salimnia, Hossein; Painter, Theresa; Wu, Fann; Procop, Gary W.; Wilson, Deborah A.; Gillespie, Wendy; Mender, Alayna; Crystal, Benjamin S.

2011-01-01

A multicenter evaluation was undertaken to evaluate the performance of a new three-color peptide nucleic acid fluorescence in situ hybridization assay that identifies isolates directly from blood cultures positive for Gram-negative bacilli (GNB). The assay correctly identified 100% (186/186) of the Escherichia coli isolates, 99.1% (109/110) of the Klebsiella pneumoniae isolates, and 95.8% (46/48) of the Pseudomonas aeruginosa isolates in this study. Negative assay results were correctly obtained for 162 of 165 other GNB (specificity, 98.2%). PMID:21490185

Direct Antimicrobial Susceptibility Testing of Gram-Negative Bacilli in Blood Cultures by an Electrochemical Method

PubMed Central

Huang, Ay Huey; Wu, Jiunn Jong; Weng, Yu Mei; Ding, Hwia Cheng; Chang, Tsung Chain

1998-01-01

Nonfastidious aerobic gram-negative bacilli (GNB) are commonly isolated from blood cultures. The feasibility of using an electrochemical method for direct antimicrobial susceptibility testing of GNB in positive blood cultures was evaluated. An aliquot (10 μl) of 1:10-diluted positive blood cultures containing GNB was inoculated into the Bactometer module well (bioMérieux Vitek, Hazelwood, Mo.) containing 1 ml of Mueller-Hinton broth supplemented with an antibiotic. Susceptibility tests were performed in a breakpoint broth dilution format, with the results being categorized as resistant, intermediate, or susceptible. Seven antibiotics (ampicillin, cephalothin, gentamicin, amikacin, cefamandole, cefotaxime, and ciprofloxacin) were used in this study, with each agent being tested at the two interpretive breakpoint concentrations. The inoculated modules were incubated at 35°C, and the change in impedance in each well was continuously monitored for 24 h by the Bactometer. The MICs of the seven antibiotics for each blood isolate were also determined by the standardized broth microdilution method. Of 146 positive blood cultures (1,022 microorganism-antibiotic combinations) containing GNB tested by the direct method, the rates of very major, major, and minor errors were 0, 1.1, and 2.5%, respectively. The impedance method was simple; no centrifugation, preincubation, or standardization of the inocula was required, and the susceptibility results were normally available within 3 to 6 h after inoculation. The rapid method may allow proper antimicrobial treatment almost 30 to 40 h before the results of the standard methods are available. PMID:9738038

[News of antibiotic resistance among Gram-negative bacilli in Algeria].

PubMed

Baba Ahmed-Kazi Tani, Z; Arlet, G

2014-06-01

Antibiotic resistance has become a major public health problem in Algeria. Indeed the past decade, we have seen a significant increase in resistance to antibiotics especially in Gram-negative bacilli. Resistance to β-lactams in enterobacteria is dominated by the production of ESBL CTX-M-3 and CTX-M-15. The strains producing these enzymes are often the cause of potentially serious infections in both hospital and community settings. Identified plasmid cephalosporinases are CMY-2, CMY-12 and DHA-1. The isolation of strains of Enterobacteriaceae and Pseudomonas aeruginosa producing carbapenemases is rare in Algeria. Some Enterobacteriaceae producing OXA-48 or VIM-19 have been reported; so far, only VIM-2 has been identified in P. aeruginosa. However, the situation regarding the strains of Acinetobacter baumannii resistant to carbapenemases seems to be more disturbing. The carbapenemase OXA-23 is the most common and seems to be endemic in the north. The carbapenemase NDM-1 has also been identified. Resistance to aminoglycosides is marked by the identification armA gene associated with blaCTX-M genes in strains of Salmonella sp. Several other resistance genes have been identified sporadically in strains of Enterobacteriaceae, P. aeruginosa and A. baumannii. Resistance genes to fluoroquinolones are more recent identification in Algeria. The most common are the Qnr determinants followed by the bifunctional enzyme AAC[6']-Ib-cr. Resistance to sulfonamides and trimethoprim was also reported in Enterobacteriaceae strains in the west of the country. Copyright © 2014. Published by Elsevier SAS.

Occurrence of bla genes encoding carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter baumannii from Intensive Care Unit in a tertiary care hospital

PubMed Central

Subramaniyan, Jayanthi Siva; Sundaram, Jeya Meenakshi

2018-01-01

CONTEXT: ICU shows increasing incidence of infection associated with the use of invasive procedures for the diagnostic purpose as well as the indiscriminate use of antibiotics. Pseudomonas aeruginosa and Acinetobacter species are “very successful” pathogen and the emergence of the Metallo-β-Lactamases (MBL) is becoming a therapeutic challenge. AIMS: To isolate the Nonfermenting Gram negative bacilli from the ICU samples. To identify the metallo betalactamase producers and to detect the bla gene presence among the Pseudomonas aeruginosa and Acinetobacter baumannii. SETTINGS AND DESIGN: The Nonfermenting Gram negative bacilli isolates from the ICU samples were taken over for 5 years (2009-2014) in a tertiary care hospital. METHODS AND MATERIALS: The isolates of Pseudomonas species and Acinetobacter species were confirmed by API analyser and processed according to standard procedures. Detection of the MBL producers were done by E strip method and subjected for bla gene detection by PCR method. RESULTS: In our study a total of 195 isolates of NFGNB were obtained from various ICU. Of these MBL producers, 26 % were Pseudomonas aeruginosa and 25 % were Acinetobacter baumannii. The subtypes of blaVIM MBL producing P.aeruginosa were 26%. The predominant gene coding for MBL activity in A.baumannii were found to be blaOXA gene 11.9%. The gene accession numbers were KF975367, KF975372. CONCLUSIONS: We have to control the development and dissemination of these superbugs among the ICU's. PMID:29692589

Outbreak of fluoroquinolone-resistant Escherichia coli infections after transrectal ultrasound-guided biopsy of the prostate.

PubMed

Dumford, Donald; Suwantarat, Nuntra; Bhasker, Vineet; Kundrapu, Sirisha; Zabarsky, Trina F; Drawz, Paul; Zhu, Hui; Donskey, Curtis J

2013-03-01

We conducted an investigation after identifying a cluster of 4 serious infections following transrectal ultrasound-guided biopsy of the prostate (TRUBP) during a 2-month period. Veterans Affairs medical center. Patients with urinary tract infection (UTI) after TRUBP and time-matched controls with no evidence of infection. The incidence of UTI within 30 days after TRUBP was calculated from 2002 through 2010. We evaluated the correlation between infection with fluoroquinolone-resistant gram-negative bacilli (GNB) and fluoroquinolone resistance in outpatient Escherichia coli urinary isolates and performed a case-control study to determine risk factors for infection with fluoroquinolone-resistant GNB. Processes for TRUBP prophylaxis, procedures, and equipment sterilization were reviewed. An outbreak of UTI due to fluoroquinolone-resistant E. coli after TRUBP began 2 years before the cluster was identified and was correlated with increasing fluoroquinolone resistance in outpatient E. coli. No deficiencies were identified in equipment processing or biopsy procedures. Fluoroquinolone-resistant E. coli UTI after TRUBP was independently associated with prior infection with fluoroquinolone-resistant GNB (adjusted odds ratio, 20.8; P=.005). A prediction rule including prior UTI, hospitalization in the past year, and previous infection with fluoroquinolone-resistant GNB identified only 17 (49%) of 35 cases. The outbreak of fluoroquinolone-resistant E. coli infections after TRUBP closely paralleled rising rates of fluoroquinolone resistance among outpatient E. coli isolates. The delayed detection of the outbreak and the absence of sensitive predictors of infection suggest that active surveillance for infection after TRUBP is necessary in the context of increasing fluoroquinolone resistance in the United States.

Drug-resistant gram-negative uropathogens: A review.

PubMed

Khoshnood, Saeed; Heidary, Mohsen; Mirnejad, Reza; Bahramian, Aghil; Sedighi, Mansour; Mirzaei, Habibollah

2017-10-01

Urinary tract infection(UTI) caused by Gram-negative bacteria is the second most common infectious presentation in community medical practice. Approximately 150 million people are diagnosed with UTI each year worldwide. Drug resistance in Gram-negative uropathogens is a major global concern which can lead to poor clinical outcomes including treatment failure, development of bacteremia, requirement for intravenous therapy, hospitalization, and extended length of hospital stay. The mechanisms of drug resistance in these bacteria are important due to they are often not identified by routine susceptibility tests and have an exceptional potential for outbreaks. Treatment of UTIs depends on the access to effective drugs, which is now threatened by antibiotic resistant Gram-negative uropathogens. Although several effective antibiotics with activity against highly resistant Gram-negatives are available, there is not a unique antibiotic with activity against the high variety of resistance. Therefore, antimicrobial susceptibility tests, correlation between clinicians and laboratories, development of more rapid diagnostic methods, and continuous monitoring of drug resistance are urgent priorities. In this review, we will discuss about the current global status of drug-resistant Gram-negative uropathogens and their mechanisms of drug resistance to provide new insights into their treatment options. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Evaluation of the β-CARBA™ test, a colorimetric test for the rapid detection of carbapenemase activity in Gram-negative bacilli.

PubMed

Bernabeu, Sandrine; Dortet, Laurent; Naas, Thierry

2017-06-01

There is an urgent need for accurate and fast diagnostic tests to identify carbapenemase-producing bacteria. Here, we have evaluated a novel colorimetric test (the β-CARBA™ test; Bio-Rad) to detect carbapenemase-producing Gram-negative bacilli from cultured colonies. The performance of the β-CARBA™ test was compared with that of the Carba NP test (or the CarbAcineto NP test) and RAPIDEC ® CARBA NP (bioMérieux) using a collection of 290 isolates with characterized β-lactamase content. This collection included 199 carbapenemase producers (121 Enterobacteriaceae, 36 Pseudomonas and 42 Acinetobacter baumannii ) and 91 non-carbapenemase producers (55 Enterobacteriaceae, 20 Pseudomonas and 16 A. baumannii ). The β-CARBA™ test correctly detected 84.9% of the carbapenemase producers, including all KPC and IMP, 96.4% of VIM, 85.3% of NDM, 80.5% of OXA-48-like and 91.2% of A. baumannii -related OXA carbapenemases (OXA-23, OXA-40, OXA-58, OXA-143 and overexpressed OXA-51). All rare metallo-β-lactamases (SPM, AIM, GIM, DIM and SIM) were detected. Importantly, all non-KPC Ambler class A carbapenemases were not detected, including GES variants with carbapenemase activity ( n  = 6), IMI ( n  = 3), NMC-A ( n  = 1), SME ( n  = 2), FRI-1 ( n  = 1) and BIC-1 ( n  = 1). All non-carbapenemase producers gave a negative result except with OXA-163-, OXA-405- and one TEM-3-producing Citrobacter freundii . The overall sensitivity and specificity of the β-CARBA™ test were 84.9% and 95.6%, respectively. This test is easy to perform and to interpret by non-specialized staff members. Despite lack of specificity towards non-KPC Ambler class A and OXA-48-like carbapenemases, the β-CARBA™ test could complete the existing panel of tests available for the confirmation of carbapenemases in Gram-negatives. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Resistance to oral antibiotics in 4569 Gram-negative rods isolated from urinary tract infection in children.

PubMed

Calzi, Anna; Grignolo, Sara; Caviglia, Ilaria; Calevo, Maria Grazia; Losurdo, Giuseppe; Piaggio, Giorgio; Bandettini, Roberto; Castagnola, Elio

2016-09-01

To investigate antibiotic resistance among pathogens isolated from urines in a tertiary care children's hospital in Italy. Retrospective analysis of prospectively collected data on antibiotic susceptibility of Gram-negatives isolated from urines at the Istituto Giannina Gaslini, Genoa - Italy from 2007 to 2014. Antibiotic susceptibility was evaluated. By means of CLSI criteria from 2007 to 2010, while from 2011 EUCAST criteria were adopted. Data on susceptibility to amoxicillin-clavulanate, co-trimoxazole, cefuroxime, nitrofurantoin, fosfomycin and ciprofloxacin were evaluated for Escherichia coli, while for other Enterobacteriaceae data were collected for amoxicillin-clavulanate, co-trimoxazole and ciprofloxacin and for ciprofloxacin against Pseudomonas aeruginosa. Univariate and multivariable analyses were performed for risk factors associated with resistance. A total of 4596 Gram-negative strains were observed in 3364 patients. A significant increase in the proportion of resistant strains was observed for E.coli against amoxicillin-clavulanate, cefuroxime and ciprofloxacin and for others Enterobacteriaceae against co-trimoxazole and ciprofloxacin. Resistance to nitrofurantoin and fosfomycin was very infrequent in E.coli. Logistic regression analysis showed that repeated episode of urinary tract infections was a risk factor for E.coli resistance to amoxicillin-clavulanate, co-trimoxazole and cefuroxime, while admission in one of the Units usually managing children with urinary tract malformations was significantly associated to resistance to amoxicillin-clavulanate and cefuroxime. In conclusion the present study shows an increase in antibiotic resistance in pediatric bacteria isolated from urines in children, especially in presence of repeated episodes and/or urinary tract malformations. This resistance is worrisome for beta-lactams and cotrimoxazole, and start to increase also for fluoroquinolones while nitrofurantoin and fosfomycin still could represent useful drugs for oral treatment of these infections. • Infections are frequent in patients with urinary tract malformations • Antibiotic prophylaxis can select for resistant pathogens What is New: • The increase in the resistance to β-lactams, co-trimoxazole or fluoroquinolones in pathogens causing urinary tract infections cause a reduction of drugs with oral formulations available for therapy • Old drugs like nitrofurantoin and fosfomycin can represent attractive compounds for oral treatment of urinary tract infections in children presence of resistance to other drug classes.

Antimicrobial Activity of a Novel Vascular Access Film Dressing Containing Chlorhexidine Gluconate.

PubMed

Wibaux, Anne; Thota, Priyaleela; Mastej, Jozef; Prince, Daniel L; Carty, Neal; Johnson, Peter

2015-01-01

Covering insertion sites with chlorhexidine impregnated dressings has been proven to be clinically effective in reducing catheter related blood stream infections (CR-BSI). Two chlorhexidine gluconate (CHG)-impregnated dressings are commercially available, a polyurethane foam disk and a film dressing containing a chlorhexidine gluconate-impregnated gel pad. While both have demonstrated efficacy in clinical settings, the major drawback of high cost and impaired IV insertion site visibility limits their usage. A new, simple film dressing containing CHG within its adhesive layer is now available. The objective of this study was to test the in vitro antimicrobial efficacy of the new dressing in comparison to the CHG-impregnated gel dressing. Quantitative aliquots of suspensions (concentration of 1.0x106 to 5.0x106 cfu/sample) of clinically relevant challenge organisms (Staphylococcus species, gram-negative bacilli, Candida albicans) were incubated in contact with the new CHG-containing film dressing, a placebo version of the same (negative control) and the commercially available CHG-impregnated gel dressing (positive control). Serial dilutions of the surviving organisms were quantified using the pour plate after 1, 3, 5, and 7 days of incubation in order to calculate an antimicrobial log10 reduction for each organism/dressing combination at each point in time. The new CHG-containing film dressing delivered greater than 5.0 log10 reduction throughout the 7 days on all aerobic gram-negative bacilli and Staphylococcus species tested. As of day 1 the CHG-containing film dressing provided greater than 5.0 log10 reduction on Candida albicans. There were no statistically significant differences in the log10 reduction between the two dressings tested. The new CHG-containing film dressing was found to be as effective as the chlorhexidine gluconate-impregnated gel dressing on clinically relevant microbes.

Aerobic Bacteria in the Diaphragmatic Portion of Stethoscope of Medical Professionals of Tertiary Care Hospital.

PubMed

Bham, G; Bhandari, J; Neupane, M R; Dawadi, R; Pradhan, P

2015-01-01

Hospital environment is a reservoir of wide varieties of microorganisms which are frequently reported colonizing in medical equipment. Stethoscopes are essential tools and of universal use in the medical profession, which might be a source of spreading nosocomial infections. This research project was conducted with an aim to assess the presence of aerobic bacteria in the stethoscope of the medical doctors working at Patan Hospital and students of Patan Academy of Health Sciences. It is a cross sectional study based on structured questionnaire and sample assessment from the stethoscope of doctors and students of Patan Hospital and Patan Academy of Health Sciences. The stethescopes used by the doctors of five major departments of Patan Hospital and students of clinical years were included in this study. Total of 99 stethoscope owned by different level of professionals (positions) and different departments were examined for bacterial contamination. Out of them, 36 were found to be considerably contaminated. Single strain of bacteria was grown from a single stethoscope. Among them 34 were Gram positive and remaining were Gram negative. Out of 34 gram postive bacteria, 29 were identified as Staphylococcus aureus, six were identified as Coagulase Negative Staphylococcus and remaining were Gram positive bacilli. There is presence of aerobic bacteria in diaphragmatic portion of stethoscope of medical professional of which the gram positives were the commonest.

Double- and multi-carbapenemase-producers: the excessively armored bacilli of the current decade.

PubMed

Meletis, G; Chatzidimitriou, D; Malisiovas, N

2015-08-01

Multidrug-resistant (MDR) and extensively drug-resistant (XDR) Gram-negative nosocomial pathogens commonly carry one carbapenemase gene conferring resistance to carbapenems and other beta-lactam antibiotics. However, increasing reports show that double-carbapenemase-producing (DCP) and even multi-carbapenemase-producing (MCP) bacteria are emerging in some parts of the world, diminishing further, in some cases, the already limited treatment options. In the present review, the up-to-date reports of DCP and MCP isolates are summarized and concerns regarding their emergence are discussed.

Simplified Protocol for Carba NP Test for Enhanced Detection of Carbapenemase Producers Directly from Bacterial Cultures

PubMed Central

Pasteran, Fernando; Tijet, Nathalie; Melano, Roberto G.

2015-01-01

We compared carbapenemase detection among 266 Gram-negative bacilli (161 carbapenemase producers) using the Carba NP tests issued by the CLSI (CNPt-CLSI) and a novel protocol (CNPt-direct) designed for carbapenemase detection direct from bacterial cultures (instead of bacterial extracts required by the CLSI tests). The specificities were comparable (100%), but the CNPt-direct was more sensitive (98% versus 84%). The CNPt-direct was easier to perform due to the direct use of colonies and offered a more robust detection of carbapenemase producers. PMID:26424841

[Antimicrobial sensitivity of the environmental microbiota in the intensive care units of a peruvian hospital].

PubMed

Díaz-Tello, José; Rojas-Jaimes, Jesús; Ibarra-Trujillo, Jimmy; Tárraga-Gonzales, Delza

2017-01-01

The objective was to detect Gram-negative bacilli and Gram-positive cocci isolated from the environmental microbiota of the Intensive Care Unit (ICU) departments of Neonatology, Pediatrics, and Transplants (kidney, liver, and general) in a Lima hospital and determine their antimicrobial sensitivity. Eighty samples were obtained from inanimate surfaces using a wet swab. A total of 61 bacterial strains were identified, including Staphylococcus epidermis (46.0%), Alcaligenes sp. (21.3%), Pseudomonas aeruginosa (16.4%), Acinetobacter sp. (13.1%), Staphylococcus aureus (1.6%), and Staphylococcus haemolyticus (1.6%). Acinetobacter sp. and P. aeruginosa showed a heightened sensitivity to the antibiotics assessed, while Alcaligenes sp. and S. epidermidis presented the highest antimicrobial resistance. It is recommended that sustained asepsis and monitoring methods be used in ICUs.

[Antimicrobial susceptibility patterns of Gram-negative bacteria isolated in urinary tract infections in Venezuela: Results of the SMART study 2009-2012].

PubMed

Guevara, Napoleón; Guzmán, Manuel; Merentes, Altagracia; Rizzi, Adele; Papaptzikos, Juana; Rivero, Narlesky; Oranges, Carmela; Vlllarroel, Héctor; Limas, Yoxsivell

2015-12-01

Antimicrobial resistance of pathogens causing urinary tract infection (UTI) is a growing problem, which complicates their effective treatment. Surveillance is needed to guide appropriate empiric therapy. to describe the susceptibility patterns of Gram-negative bacteria isolated of patients with UTI to twelve antibiotics as part of the Study for Monitoring Antimicrobial Resistance Trends in Venezuela. Between 2009-2012 a total of 472 Gram-negative bacteria were isolated from hospitalized patients with UTI. The isolates were sent to Central Laboratory (Central Laboratory of International Health Management Associates) to confirm their identification, and to make susceptibility testing as recommended by the Clinical and Laboratory Standards Institute. Enterobacteriacea comprised 96.6% of the total, where Escherichia coli (76.9%) and Klebsiella pneumoniae (10.6%) were the most frequent. Extended-spectrum β-lactamases (ESBL) was detected in 21.6% of isolates. Top antimicrobial activity were ertapenem, imipenem, and amikacin (> 90.0%), slightly lower for amikacin (85.1%) in ESBL-producing strains. Resistance rates to fluoroquinolones and ampicillin/sulbactam were high (40 y 64%, respectively). These data suggest a necessary revision of the therapeutic regimens for the empirical treatment of UTI in Venezuela.

First described case of prosthetic joint infection with Clostridium disporicum.

PubMed

McBride, Joseph A; Sterkel, Alana K; Rehrauer, William M; Smith, Jeannina A

2017-12-01

An orthopedic hardware infection with Clostridium disporicum is described. C. disporicum is a gram positive anaerobic bacillus which can contain two subterminal spores. C. disporicum had not previously been reported in musculoskeletal infections. Gram stains demonstrating gram positive bacilli with two subterminal spores should alert practitioners to the possibility of C. disporicum infection. Published by Elsevier Ltd.

Bacterial profile and drug susceptibility pattern of urinary tract infection in pregnant women at University of Gondar Teaching Hospital, Northwest Ethiopia.

PubMed

Alemu, Agersew; Moges, Feleke; Shiferaw, Yitayal; Tafess, Ketema; Kassu, Afework; Anagaw, Belay; Agegn, Abebe

2012-04-25

Urinary tract infection (UTI) is a common health problem among pregnant women. Proper investigation and prompt treatment are needed to prevent serious life threatening condition and morbidity due to urinary tract infection that can occur in pregnant women. Recent report in Addis Ababa, Ethiopia indicated the prevalence of UTI in pregnant women was 11.6% and Gram negative bacteria was the predominant isolates and showed multi drug resistance. This study aimed to assess bacterial profile that causes urinary tract infection and their antimicrobial susceptibility pattern among pregnant women visiting antenatal clinic at University of Gondar Teaching Hospital, Northwest Ethiopia. A cross-sectional study was conducted at University of Gondar Teaching Hospital from March 22 to April 30, 2011. Mid stream urine samples were collected and inoculated into Cystine Lactose Electrolyte Deficient medium (CLED). Colony counts yielding bacterial growth of 105/ml of urine or more of pure isolates were regarded as significant bacteriuria for infection. Colony from CLED was sub cultured onto MacConkey agar and blood agar plates. Identification was done using cultural characteristics and a series of biochemical tests. A standard method of agar disc diffusion susceptibility testing method was used to determine susceptibility patterns of the isolates. The overall prevalence of UTI in pregnant women was 10.4%. The predominant bacterial pathogens were Escherichia coli 47.5% followed by coagulase-negative staphylococci 22.5%, Staphylococcus aureus 10%, and Klebsiella pneumoniae 10%. Gram negative isolates were resulted low susceptibility to co-trimoxazole (51.9%) and tetracycline (40.7%) whereas Gram positive showed susceptibility to ceftriaxon (84.6%) and amoxicillin-clavulanic acid (92.3%). Multiple drug resistance (resistance to two or more drugs) was observed in 95% of the isolates. Significant bacteriuria was observed in asymptomatic pregnant women. Periodic studies are recommended to check the outcome of asymptomatic bacteriuria and also monitor any changes in the susceptibility patterns of urinary tract pathogens in pregnant women.

Application of WHONET in the Antimicrobial Resistance Surveillance of Uropathogens: A First User Experience from Nepal

PubMed Central

Ghosh, A.N.; Bhatta, D.R.; Ansari, M.T.; Tiwari, H.K.; Mathuria, J.P.; Gaur, A.; Supram, H.S.; Gokhale, S.

2013-01-01

Introduction: WHONET is a freely downloadable, Windows-based database software which is used for the management and analysis of microbiology data, with a special focus on the analysis of antimicrobial susceptibility test results. Urinary Tract Infections (UTI) are a common medical problem and they are responsible for notable morbidity among young and sexually active women. Objectives: The major objective of this study was the utilization and application of the WHONET program for the Antimicrobial Resistance (AMR) surveillance of uropathogens. Methods: A total of 3209 urine samples were collected from patients who visited Manipal Teaching Hospital with a clinical suspicion of UTI, during December 2010 to July 2011. The isolation and characterization of the isolates were done by conventional methods. Antimicrobial Susceptibility Testing (AST) was performed by Kirby Bauer’s disc diffusion method. The data entry and analysis were done by using the WHONET 5.6 software. Results: Out of the 3209 specimens, 497 bacterial isolates were obtained and they were subjected to AST. Escherichia coli (66.2%) was the commonest bacterial isolate, followed by Enterococcus species (9.3%), Staphylococcus aureus (5.0%), and Klebsiella pneumoniae (4.2%). Among the gram-negative enteric bacilli, a high prevalence of resistance was observed against ampicillin and ciprofloxacin. The gram negative nonfermenters exhibited a high degree of resistance to ceftazidime. Staphylococcus species. showed a moderately high resistance to co-trimoxazole. One isolate was Vancomycin Resistant Enterococci (VRE). Conclusion: This study, a first of its kind which was done in Nepal, was carried out by using the WHONET software to monitor, analyze and share the antimicrobial susceptibility data at various levels. This study was also aimed at building a surveillance network in Nepal, with the National Public Health Laboratory, Nepal, acting as a nodal centre. This would help in the formulation of antibiotic policies and in identifying hospital and community outbreaks at the nodal centre, as well as in sharing information with the clinicians at the local level. PMID:23814725

Application of WHONET in the Antimicrobial Resistance Surveillance of Uropathogens: A First User Experience from Nepal.

PubMed

Ghosh, A N; Bhatta, D R; Ansari, M T; Tiwari, H K; Mathuria, J P; Gaur, A; Supram, H S; Gokhale, S

2013-05-01

WHONET is a freely downloadable, Windows-based database software which is used for the management and analysis of microbiology data, with a special focus on the analysis of antimicrobial susceptibility test results. Urinary Tract Infections (UTI) are a common medical problem and they are responsible for notable morbidity among young and sexually active women. The major objective of this study was the utilization and application of the WHONET program for the Antimicrobial Resistance (AMR) surveillance of uropathogens. A total of 3209 urine samples were collected from patients who visited Manipal Teaching Hospital with a clinical suspicion of UTI, during December 2010 to July 2011. The isolation and characterization of the isolates were done by conventional methods. Antimicrobial Susceptibility Testing (AST) was performed by Kirby Bauer's disc diffusion method. The data entry and analysis were done by using the WHONET 5.6 software. Out of the 3209 specimens, 497 bacterial isolates were obtained and they were subjected to AST. Escherichia coli (66.2%) was the commonest bacterial isolate, followed by Enterococcus species (9.3%), Staphylococcus aureus (5.0%), and Klebsiella pneumoniae (4.2%). Among the gram-negative enteric bacilli, a high prevalence of resistance was observed against ampicillin and ciprofloxacin. The gram negative nonfermenters exhibited a high degree of resistance to ceftazidime. Staphylococcus species. showed a moderately high resistance to co-trimoxazole. One isolate was Vancomycin Resistant Enterococci (VRE). This study, a first of its kind which was done in Nepal, was carried out by using the WHONET software to monitor, analyze and share the antimicrobial susceptibility data at various levels. This study was also aimed at building a surveillance network in Nepal, with the National Public Health Laboratory, Nepal, acting as a nodal centre. This would help in the formulation of antibiotic policies and in identifying hospital and community outbreaks at the nodal centre, as well as in sharing information with the clinicians at the local level.

[Nosocomial infection in patients receiving a solid organ transplant or haematopoietic stem cell transplant].

PubMed

Moreno Camacho, Asunción; Ruiz Camps, Isabel

2014-01-01

Bacterial infections are the most common infections in solid organ transplant recipients. These infections occur mainly in the first month after transplantation and are hospital-acquired. Nosocomial infections cause significant morbidity and are the most common cause of mortality in this early period of transplantation. These infections are caused by multi-drug resistant (MDR) microorganisms, mainly Gram-negative enterobacteria, non-fermentative Gram-negative bacilli, enterococci, and staphylococci. The patients at risk of developing nosocomial bacterial infections are those previously colonized with MDR bacteria while on the transplant waiting list. Intravascular catheters, the urinary tract, the lungs, and surgical wounds are the most frequent sources of infection. Preventive measures are the same as those applied in non-immunocompromised, hospitalized patients except in patients at high risk for developing fungal infection. These patients need antifungal therapy during their hospitalization, and for preventing some bacterial infections in the early transplant period, patients need vaccinations on the waiting list according to the current recommendations. Although morbidity and mortality related to infectious diseases have decreased during the last few years in haematopoietic stem cell transplant recipients, they are still one of the most important complications in this population. Furthermore, as occurs in the general population, the incidence of nosocomial infections has increased during the different phases of transplantation. It is difficult to establish general preventive measures in these patients, as there are many risk factors conditioning these infections. Firstly, they undergo multiple antibiotic treatments and interventions; secondly, there is a wide variability in the degree of neutropenia and immunosuppression among patients, and finally they combine hospital and home stay during the transplant process. However, some simple measures could be implemented to improve the current situation. Copyright © 2014 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Efficacy of polymyxin B-immobilized fiber hemoperfusion for patients with septic shock caused by Gram-negative bacillus infection.

PubMed

Saito, Nobuyuki; Sugiyama, Kazuhiro; Ohnuma, Testu; Kanemura, Takashi; Nasu, Michitaka; Yoshidomi, Yuya; Tsujimoto, Yuta; Adachi, Hiroshi; Koami, Hiroyuki; Tochiki, Aito; Hori, Kota; Wagatsuma, Yukiko; Matsumoto, Hisashi

2017-01-01

Septic shock-associated mortality in intensive care units (ICUs) remains high, with reported rates ranging 30-50%. In particular, Gram-negative bacilli (GNB), which induce significant inflammation and consequent multiple organ failure, are the etiological bacterial agent in 40% of severe sepsis cases. Hemoperfusion using polymyxin B-immobilized fiber (PMX), which adsorbs endotoxin, is expected to reduce the inflammatory sepsis cascade due to GNB. However, the clinical efficacy of this treatment has not yet been demonstrated. Here, we aimed to verify the efficacy of endotoxin adsorption therapy using PMX through a retrospective analysis of 413 patients who received broad spectrum antimicrobial treatment for GNB-related septic shock between January 2009 and December 2012 in 11 ICUs of Japanese tertiary hospitals. After aligning the patients' treatment time phases, we classified patients in two groups depending on whether PMX hemoperfusion (PMXHP) therapy was administered or not within 24 hours after ICU admission (PMXHP group: n = 134, conventional group: n = 279). The primary study endpoint was the mortality rate at 28 days after ICU admission. The mean age was 72.4 (standard deviation: 12.6) years, and the mean Sequential Organ Failure Assessment score at ICU admission was 9.9 (3.4). The infection sites included intra-abdominal (38.0%), pulmonary (18.9%), and urinary tract (32.2%), and two thirds of all patients had GNB-related bacteremia. Notably, the mortality at 28 days after ICU admission did not differ between the groups (PMXHP: 29.1% vs. conventional: 29.0%, P = 0.98), and PMXHP therapy was not found to improve this outcome in a Cox regression analysis (hazard ratio = 1.16; 95% confidence interval, 0.81-1.64, P = 0.407). We conclude that PMX-based endotoxin adsorption within 24 hours from ICU admission was not associated with mortality among patients with septic shock due to GNB. University Hospital Medical Information Network Clinical Trial Registry (UMIN-CTR ID: UMIN000012748).

Rapid Discrimination of Gram-Positive and Gram-Negative Bacteria in Liquid Samples by Using NaOH-Sodium Dodecyl Sulfate Solution and Flow Cytometry

PubMed Central

Wada, Atsushi; Kono, Mari; Kawauchi, Sawako; Takagi, Yuri; Morikawa, Takashi; Funakoshi, Kunihiro

2012-01-01

Background For precise diagnosis of urinary tract infections (UTI), and selection of the appropriate prescriptions for their treatment, we explored a simple and rapid method of discriminating gram-positive and gram-negative bacteria in liquid samples. Methodology/Principal Findings We employed the NaOH-sodium dodecyl sulfate (SDS) solution conventionally used for plasmid extraction from Escherichia coli and the automated urine particle analyzer UF-1000i (Sysmex Corporation) for our novel method. The NaOH-SDS solution was used to determine differences in the cell wall structures between gram-positive and gram-negative bacteria, since the tolerance to such chemicals reflects the thickness and structural differences of bacterial cell walls. The UF-1000i instrument was used as a quantitative bacterial counter. We found that gram-negative bacteria, including E. coli, in liquid culture could easily be lysed by direct addition of equal volumes of NaOH-SDS solution. In contrast, Enterococcus faecalis, which is a gram-positive bacterium, could not be completely lysed by the solution. We then optimized the reaction time of the NaOH-SDS treatment at room temperature by using 3 gram-positive and 4 gram-negative bacterial strains and determined that the optimum reaction time was 5 min. Finally, in order to evaluate the generalizability of this method, we treated 8 gram-positive strains and 8 gram-negative strains, or 4 gram-positive and 4 gram-negative strains incubated in voluntary urine from healthy volunteers in the same way and demonstrated that all the gram-positive bacteria were discriminated quantitatively from gram negative bacteria using this method. Conclusions/Significance Using our new method, we could easily discriminate gram-positive and gram-negative bacteria in liquid culture media within 10 min. This simple and rapid method may be useful for determining the treatment course of patients with UTIs, especially for those without a prior history of UTIs. The method may be easily applied in order to obtain additional information for clinical prescriptions from bacteriuria. PMID:23077549

Effect of selective decontamination on antimicrobial resistance in intensive care units: a systematic review and meta-analysis.

PubMed

Daneman, Nick; Sarwar, Syed; Fowler, Robert A; Cuthbertson, Brian H

2013-04-01

Many meta-analyses have shown reductions in infection rates and mortality associated with the use of selective digestive decontamination (SDD) or selective oropharyngeal decontamination (SOD) in intensive care units (ICUs). These interventions have not been widely implemented because of concerns that their use could lead to the development of antimicrobial resistance in pathogens. We aimed to assess the effect of SDD and SOD on antimicrobial resistance rates in patients in ICUs. We did a systematic review of the effect of SDD and SOD on the rates of colonisation or infection with antimicrobial-resistant pathogens in patients who were critically ill. We searched for studies using Medline, Embase, and Cochrane databases, with no limits by language, date of publication, study design, or study quality. We included all studies of selective decontamination that involved prophylactic application of topical non-absorbable antimicrobials to the stomach or oropharynx of patients in ICUs, with or without additional systemic antimicrobials. We excluded studies of interventions that used only antiseptic or biocide agents such as chlorhexidine, unless antimicrobials were also included in the regimen. We used the Mantel-Haenszel model with random effects to calculate pooled odds ratios. We analysed 64 unique studies of SDD and SOD in ICUs, of which 47 were randomised controlled trials and 35 included data for the detection of antimicrobial resistance. When comparing data for patients in intervention groups (those who received SDD or SOD) versus data for those in control groups (who received no intervention), we identified no difference in the prevalence of colonisation or infection with Gram-positive antimicrobial-resistant pathogens of interest, including meticillin-resistant Staphylococcus aureus (odds ratio 1·46, 95% CI 0·90-2·37) and vancomycin-resistant enterococci (0·63, 0·39-1·02). Among Gram-negative bacilli, we detected no difference in aminoglycoside-resistance (0·73, 0·51-1·05) or fluoroquinolone-resistance (0·52, 0·16-1·68), but we did detect a reduction in polymyxin-resistant Gram-negative bacilli (0·58, 0·46-0·72) and third-generation cephalosporin-resistant Gram-negative bacilli (0·33, 0·20-0·52) in recipients of selective decontamination compared with those who received no intervention. We detected no relation between the use of SDD or SOD and the development of antimicrobial-resistance in pathogens in patients in the ICU, suggesting that the perceived risk of long-term harm related to selective decontamination cannot be justified by available data. However, our study indicates that the effect of decontamination on ICU-level antimicrobial resistance rates is understudied. We recommend that future research includes a non-crossover, cluster randomised controlled trial to assess long-term ICU-level changes in resistance rates. None. Copyright © 2013 Elsevier Ltd. All rights reserved.

Case of a lung mass due to melioidosis in Mexico.

PubMed

Truong, Kimberly K; Moghaddam, Samer; Al Saghbini, Samer; Saatian, Bahman

2015-05-06

Melioidosis, an infection caused by the gram-negative bacterium Burkholderia pseudomallei, is an important cause of pneumonia, skin infection, sepsis, and death in Southeast Asia and Australia, but is exceedingly rare in North America. Pulmonary melioidosis typically presents as acute bacterial pneumonia or cavitary lung lesions resembling tuberculosis. We report melioidosis in a 70-year-old active smoker from Mexico with no history of travel to disease-endemic areas. The patient presented with a left supraclavicular abscess and a non-cavitary, left lung mass encasing a pulmonary vein. Incision and drainage of the patient's subcutaneous abscess isolated B. pseudomallei, and fine-needle aspiration of enlarged mediastinal lymph nodes revealed the presence of intracellular gram-negative bacilli with no evidence of malignancy. Biochemical tests determined that the strain the patient acquired from Mexico is identical to only 1 other isolate from Thailand. This report highlights the blurring epidemiological borders of this organism, its rare presentation mimicking lung malignancy, and an aggressive antimicrobial treatment that resulted in resolution of the patient's symptoms.

A case of bacterial peritonitis caused by Roseomonas mucosa in a patient undergoing continuous ambulatory peritoneal dialysis.

PubMed

Matsukuma, Yuta; Sugawara, Koji; Shimano, Shota; Yamada, Shunsuke; Tsuruya, Kazuhiko; Kitazono, Takanari; Higashi, Harumichi

2014-11-01

Bacterial peritonitis remains a life-threatening complication of peritoneal dialysis (PD). Roseomonas is a bacterial genus of pink-pigmented, oxidized, gram-negative coccobacilli that was first named in 1993. Importantly, Roseomonas mucosa exhibits antibiotic resistance, with significant resistance to cephalosporin, which is often selected as an empirical antibiotic regimen for peritonitis in PD patients. We herein report the case of a PD patient with bacterial peritonitis caused by Roseomonas mucosa that was fortunately identified using 16S rRNA gene sequencing and successfully treated with ciprofloxacin. Given that Roseomonas demonstrates resistance to a variety of antibiotics. The administration of empiric antibiotic therapy based on the recommendation of the International Society of Peritoneal Dialysis guidelines occasionally fails, leading to the aggravation of bacterial peritonitis. Hence, nephrologists should consider Roseomonas as one of the potential causative organisms of peritonitis, especially when gram-negative bacilli are resistant to cephalosporin and cannot be identified using standard laboratory methods.

Silver enhances antibiotic activity against gram-negative bacteria.

PubMed

Morones-Ramirez, J Ruben; Winkler, Jonathan A; Spina, Catherine S; Collins, James J

2013-06-19

A declining pipeline of clinically useful antibiotics has made it imperative to develop more effective antimicrobial therapies, particularly against difficult-to-treat Gram-negative pathogens. Silver has been used as an antimicrobial since antiquity, yet its mechanism of action remains unclear. We show that silver disrupts multiple bacterial cellular processes, including disulfide bond formation, metabolism, and iron homeostasis. These changes lead to increased production of reactive oxygen species and increased membrane permeability of Gram-negative bacteria that can potentiate the activity of a broad range of antibiotics against Gram-negative bacteria in different metabolic states, as well as restore antibiotic susceptibility to a resistant bacterial strain. We show both in vitro and in a mouse model of urinary tract infection that the ability of silver to induce oxidative stress can be harnessed to potentiate antibiotic activity. Additionally, we demonstrate in vitro and in two different mouse models of peritonitis that silver sensitizes Gram-negative bacteria to the Gram-positive-specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. Finally, we used silver and antibiotic combinations in vitro to eradicate bacterial persister cells, and show both in vitro and in a mouse biofilm infection model that silver can enhance antibacterial action against bacteria that produce biofilms. This work shows that silver can be used to enhance the action of existing antibiotics against Gram-negative bacteria, thus strengthening the antibiotic arsenal for fighting bacterial infections.

Novel Guanidine Compound against Multidrug-Resistant Cystic Fibrosis-Associated Bacterial Species.

PubMed

Saeed, Aamer; Bosch, Alejandra; Bettiol, Marisa; Nossa González, Diana L; Erben, Mauricio Federico; Lamberti, Yanina

2018-05-11

Chronic pulmonary infection is a hallmark of lung disease in cystic fibrosis (CF). Infections dominated by non-fermentative Gram-negative bacilli are particularly difficult to treat and highlight an urgent need for the development of new class of agents to combat these infections. In this work, a small library comprising thiourea and guanidine derivatives with low molecular weight was designed; these derivatives were studied as antimicrobial agents against Gram-positive, Gram-negative, and a panel of drug-resistant clinical isolates recovered from patients with CF. One novel compound, a guanidine derivative bearing adamantane-1-carbonyl and 2-bromo-4,6-difluouro-phenyl substituents ( H-BDF ), showed potent bactericidal activity against the strains tested, at levels generally higher than those exhibited by tobramycin, ceftazimide and meropenem. The role that different substituents exert in the antimicrobial activity has been determined, highlighting the importance of the halo-phenyl group in the guanidine moiety. The new compound displays low levels of cytotoxicity against THP-1 and A549 cells with a selective index (SI) > 8 (patent application PCT/IB2017/054870, August 2017). Taken together, our results indicate that H-BDF can be considered as a promising antimicrobial agent.

Comparison of antral tap with endoscopically directed nasal culture.

PubMed

Casiano, R R; Cohn, S; Villasuso, E; Brown, M; Memari, F; Barquist, E; Namias, N

2001-08-01

The diagnosis of acute bacterial rhinosinusitis continues to generate controversy in critically ill patients. The efficacy of endoscopically directed cultures in these patients is unknown. We compared antral tap (AT) with endoscopic tissue culture (ETC) of the osteomeatal complex in an intensive care unit (ICU) setting. Twenty patients admitted to a surgical/trauma ICU were evaluated by AT and ENB for the presence of rhinosinusitis. All patients had 1) a fever of unknown origin without resolution on empiric antibiotic therapy for > or =48 hrs; 2) other sources of fever ruled out; 3) computed tomography scan evidence of mucoperiosteal thickening +/- sinus air/fluid levels; and 4) attempt at conservative treatment with topical decongestants and removal of all nasal intubation. Microbiologic data were collected and analyzed for any statistical difference between groups. A total of 29 sides underwent simultaneous tap and endoscopically directed tissue culture. The mean age was 40 years (range, 23-77 y) with 85% being males. Fifteen of 20 (75%) patients in the AT group were culture-positive. Of the 49 isolates from the AT, 55% yielded Gram-negative bacilli (Acinetobacter sp. 37%) and 45% yielded Gram-positive cocci. The ETC group was culture-positive in 18 of 20 (90%) patients. Of the 52 isolates from the ETC, Gram-negative bacilli were found in 58% (Acinetobacter sp. 33%) and 42% yielded Gram-positive cocci. The ETCs were culture-positive in all but 1 patient with positive taps. There appeared to be a concordance between AT and ETC in 60% of the patients. In five instances (25%), results of the AT or ETC changed ICU management. Two patients ultimately required sinus surgery. Sinus taps and/or endoscopically directed tissue cultures led to a change in ICU care in 25% of ICU patients studied. In patients with fever of unknown origin and computed tomography evidence of sinusitis, an antral tap continues to provide important information concerning maxillary sinusitis. However, ETC may give as good a representation of the microbiology and secondary inflammatory changes responsible for bacterial ICU rhinosinusitis causing fever of unknown origin. Further study on a larger group of patients is needed.

Bacteriological profile of neonatal sepsis in a secondary care hospital in rural Tamil Nadu, Southern India.

PubMed

Pavan Kumar, Doniparthi Venkata; Mohan, Jesinth; Rakesh, P S; Prasad, Jasmine; Joseph, Lenikumar

2017-01-01

Neonatal sepsis is a leading cause of neonatal mortality and morbidity in the world. The objective of the current study was to detect the common causative microorganisms of neonatal sepsis and their antimicrobial resistance patterns in a rural secondary hospital in Tamil Nadu, India. Neonates (0-28 days) admitted to this newborn care unit from October 2013 to September 2015, with a diagnosis of probable sepsis were studied. All the enrolled babies had blood cultures taken and were followed up till final outcome, which was discharge or death, irrespective of culture result. Univariate analysis was performed for factors associated with culture positivity, generating odds ratios, and confidence intervals. Among the 107 babies with a diagnosis of probable sepsis, 28 (26.2%) had shown bacteria in culture. The majority (94.4%) were of early-onset sepsis. The predominant organisms were Staphylococcus aureus (10/28) and Klebsiella (6/28). 100% of Gram-negative bacilli and 90% of Staphylococcus were resistant to Ampicillin. Gentamicin resistance among Gram-negative bacilli and Staphylococcus was 52.9% and 20%, respectively, while third-generation cephalosporin resistance was 31.2% and 20%, respectively. Among the neonates diagnosed as probable sepsis, idiopathic prematurity ( P = 0.007) was found to have a statistically significant association with culture-positive sepsis. The culture positivity rate among the neonates with probable sepsis in the current study was 26%. An alarmingly high degree of antibiotic resistance observed calls for robust infection control practices and an urgent evaluation and development of individual and national antibiotic policies for neonatal sepsis.

Beta-lactams in continuous infusion for Gram-negative bacilli osteoarticular infections: an easy method for clinical use.

PubMed

Ribera, Alba; Soldevila, Laura; Rigo-Bonnin, Raul; Tubau, Fe; Padullés, Ariadna; Gómez-Junyent, Joan; Ariza, Javier; Murillo, Oscar

2018-04-01

Continuous infusion (CI) of beta-lactams could optimize their pharmacokinetic/pharmacodynamic indices, especially in difficult-to-treat infections. To validate an easy-to-use method to guide beta-lactams dosage in CI (formula). A retrospective analysis was conducted of a prospectively collected cohort (n = 24 patients) with osteoarticular infections caused by Gram-negative bacilli (GNB) managed with beta-lactams in CI. Beta-lactams dose was calculated using a described formula (daily dose = 24 h × beta-lactam clearance × target "steady-state" concentration) to achieve concentrations above the MIC. We correlated the predicted concentration (C pred  = daily dose/24 h × beta-lactam clearance) with the patient's observed concentration (C obs ) measured by UPLC-MS/MS (Spearman's coefficient). The most frequent microorganism treated was P. aeruginosa (21 cases; 9 MDR). Beta-lactams in CI were ceftazidime (n = 14), aztreonam (7), and piperacillin/tazobactam (3), mainly used in combination (12 with colistin, 5 with ciprofloxacin) and administered without notable side effects. The plasma C obs was higher overall than C pred ; the Spearman correlation between both concentrations was rho = 0.6 (IC 95%: 0.2-0.8) for all beta-lactams, and rho = 0.8 (IC 95%: 0.4-1) for those treated with ceftazidime. The formula may be useful in clinical practice for planning the initial dosage of beta-lactams in CI, while we await a systematic therapeutic drug monitoring. The use of beta-lactams in CI was safe.

10 x '20 Progress--development of new drugs active against gram-negative bacilli: an update from the Infectious Diseases Society of America.

PubMed

Boucher, Helen W; Talbot, George H; Benjamin, Daniel K; Bradley, John; Guidos, Robert J; Jones, Ronald N; Murray, Barbara E; Bonomo, Robert A; Gilbert, David

2013-06-01

Infections caused by antibiotic-resistant bacteria, especially the "ESKAPE" pathogens, continue to increase in frequency and cause significant morbidity and mortality. New antimicrobial agents are greatly needed to treat infections caused by gram-negative bacilli (GNB) resistant to currently available agents. The Infectious Diseases Society of America (IDSA) continues to propose legislative, regulatory, and funding solutions to this continuing crisis. The current report updates the status of development and approval of systemic antibiotics in the United States as of early 2013. Only 2 new antibiotics have been approved since IDSA's 2009 pipeline status report, and the number of new antibiotics annually approved for marketing in the United States continues to decline. We identified 7 drugs in clinical development for treatment of infections caused by resistant GNB. None of these agents was included in our 2009 list of antibacterial compounds in phase 2 or later development, but unfortunately none addresses the entire spectrum of clinically relevant GNB resistance. Our survey demonstrates some progress in development of new antibacterial drugs that target infections caused by resistant GNB, but progress remains alarmingly elusive. IDSA stresses our conviction that the antibiotic pipeline problem can be solved by the collaboration of global leaders to develop creative incentives that will stimulate new antibacterial research and development. Our aim is the creation of a sustainable global antibacterial drug research and development enterprise with the power in the short term to develop 10 new, safe, and efficacious systemically administered antibiotics by 2020 as called for in IDSA's "10 × '20 Initiative."

BACTERIAL CONTAMINATION OF STETHOSCOPES

PubMed Central

Bukharie, Huda A.; Al-Zahrani, Hussain; Rubaish, Abdullah M.; Abdulmohsen, Mohammed F.

2004-01-01

Background: A stethoscope, an essential tool of the medical profession, can become a source of nosocomial infection. Objective: To determine the frequency of bacterial contamination of stethoscopes as well as the practices used for cleaning them. Methods: Cultures were taken from 100 stethoscopes used by different medical personnel in different hospital services. The stethoscopes were collected while the staff filled in a questionnaire. Results: Thirty (30%) out of the 100 stethoscopes surveyed were contaminated with microorganisms. The majority of organisms isolated were gram-positive bacteria (gram positive bacilli 12%, gram-negative bacteria 9%, gram-positive cocci 9%). None of the stethoscopes grew methicillin-resistant staphylococcus aureus. Overall, 21% of the health personnel cleaned their stethoscopes daily, 47% weekly, and 32% yearly. None of the health care workers cleaned their stethoscopes after every patient. Nurses cleaned their stethoscopes more often than physicians and medical students. Conclusion: Stethoscopes may be important in the spread of infectious agents. Their regular disinfection after use on each patient should be considered, particularly in such areas of the hospital, as the critical care units, and oncology units which house many patients with antibiotic-resistant organisms. PMID:23012043

Does negative-pressure wound therapy influence subjacent bacterial growth? A systematic review.

PubMed

Glass, Graeme E; Murphy, George R F; Nanchahal, Jagdeep

2017-08-01

Negative-pressure wound therapy is a ubiquitous wound management resource. The influence of NPWT on the bacterial bioburden of the subjacent wound remains unclear. We sought to examine the evidence. MEDLINE, Embase, PubMed, the Cochrane Database of Systematic Reviews and the Cochrane Controlled Trials Register were searched for articles quantitatively evaluating bacterial load under NPWT. Twenty-four studies met the inclusion criteria including 4 randomised controlled trials, 8 clinical series and 12 experimental studies. Twenty studies evaluated conventional NPWT, while 4 evaluated infiltration-based NPWT. While 8 studies using conventional NPWT failed to demonstrate an observable effect on bacterial load, 7 studies reported that NPWT was inherently bacteriostatic and 5 others reported species selectivity with suppression of non-fermentative gram-negative bacilli (NFGNB), including Pseudomonas spp. Simultaneously, there was some evidence of enhanced proliferation of gram-positive cocci where the niche was cleared of NFGNB. Two of the 4 studies using infiltration-based NPWT also reported selectively impaired proliferation of Pseudomonas spp. The assumption that NPWT suppresses bacterial proliferation is oversimplified. There is evidence that NPWT exhibits species selectivity, suppressing the proliferation of NFGNB. However, this may depopulate the niche for exploitation by gram-positive cocci. This, in turn, has implications for the use of NPWT where highly virulent strains of gram-positive cocci have been isolated and the duration of NPWT therapy and frequency of dressing changes. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

ANTIBIOTIC RESISTANCE SPECTRUM OF NON FERMENTING GRAM NEGATIVE BACILLI ISOLATED IN THE ORTHOPEDIC TRAUMATOLOGY CLINIC OF "SF. SPIRIDON" CLINICAL EMERGENCY HOSPITAL IAŞI.

PubMed

Tucaliuc, D; Alexa, O; Tuchiluş, Cristina Gabriela; Ursu, Ramona Gabriela; Tucaliuc, Elena Simona; Jelihovsky, I; Iancu, Luminiţa Smaranda

2015-01-01

The retro-prospective analysis of antibiotic sensitivity of non-fermenting gram negative bacilli strains circulating in the Orthopedics-Traumatology Clinic from "Sf. Spiridon" Emergency Clinical Hospital in view of determining the trend of the resistance phenomenon and indicating the most useful treatment for the infections caused by these strains. The retrospective component was conducted from 01.01.2003 to 31.12.2012, and the result of the diffusimetric antibiograms was taken from the hospital's informatics system; the prospective component of the study involved the collection of pathological products from the patients admitted during January-December 2013, who showed clinical suspicion of infection, in compliance with the general collection norms for the products destined for the bacteriological exam. From the total 167 strains of Pseudomonas aeruginosa isolated and identified from the patients, 48 (28.74%) were sensitive to at least one antibiotic from each tested class, 29 (17.39%) were resistant to a single antibiotic and the rest of 90 (53.89%) showed multiple resistance. We noticed a statistically significant difference between the number of strains sensitive to at least one antibiotic from each tested class and those with multiple resistance (p < 0.05). For the strains of Acinetobacter baumanii combined resistance was identified for 121 (87.04%), out of which 55 (39.56%) were resistant to two classes of antibiotics and the other (47.48%) to all three classes. The most frequently met was the association of resistance to quinolones and aminoglycosides, namely for a number of 49 strains (35.25%); only 3.59% of them were simultaneously sensitive to the three classes of antibiotics. The already high percentages and the rising trends of antibiotic resistance of non-fermenting gram-negative bacteria described in this study confirm the continuous decrease of the efficiency of antimicrobial agents and underline the necessity of a global strategy which aims at all health sectors regarding the rational use of antibiotics, on the one hand, and the continuation of studies concerning the surveillance of the antimicrobial resistance phenomenon, on the other hand.

Asymptomatic bacteriuria of pregnancy in Ibadan, Nigeria: a re-assessment.

PubMed

Akinloye, O; Ogbolu, D O; Akinloye, O M; Terry Alli, O A

2006-01-01

Asymptomatic bacteriuria in pregnancy is the major risk factor for developing symptomatic urinary tract infection during pregnancy. In the present study, 300 pregnant women are screened for significant asymptomatic bacteriuria in order to provide an insight into the prevalence in developing countries, reassessment of some predisposing factors and aetiological agents and their susceptibility tests. The mean age of the patients in the study is 26.8 years (SD: 5.8 years, range: 16-40 years). Using 10(3) organisms/mL as a significant level of bacteriuria, the prevalence was found to be 21.0%. One hundred and fifty-eight samples had no pus cells, with 25 showing significant bacteriuria, 116 samples contained 1-4 pus cells/high power field (hpf) with 25 showing significant bacteriuria, while 26 samples had > or = 5 pus cells/hpf with 13 showing significant bacteriuria. There was no particular trend associated with age and rate of infection. However, there was a decline in the rate of infection in the 26-30 age group, with a sharp increase as age increased. There was high incidence of bacteriuria during the third trimester of pregnancy (21.9%) compared with that in the first trimester (7.7%), while the level in the second trimester was 22.5%. Multiparity is associated with increased bacteriuria in pregnancy. Thirty-one (49.2%) isolates grew Gram-negative bacilli; 27 (42.9%) grew Gram-positive cocci and the remainder (7.9%) grew yeast-like cells. Staphylococcus aureus was the most frequent pathogen (41.3%), followed by Klebsiella species (33.3%) and Escherichia coli (11.1%). Bacterial isolates from this study were most sensitive to ceftazidime, followed by ceftriazone, and least susceptible to co-trimoxazole.

A prediction tool for nosocomial multi-drug Resistant Gram-Negative Bacilli infections in critically ill patients - prospective observational study.

PubMed

Vasudevan, Anupama; Mukhopadhyay, Amartya; Li, Jialiang; Yuen, Eugene Goh Yu; Tambyah, Paul Ananth

2014-11-25

The widespread use of empiric broad spectrum antibiotics has contributed to the global increase of Resistant Gram-Negative Bacilli (RGNB) infections in intensive care units (ICU). The aim of this study was to develop a tool to predict nosocomial RGNB infections among ICU patients for targeted therapy. We conducted a prospective observational study from August'07 to December'11. All adult patients who were admitted and stayed for more than 24 hours at the medical and surgical ICU's were included. All patients who developed nosocomial RGNB infections 48 hours after ICU admission were identified. A prediction score was formulated by using independent risk factors obtained from logistic regression analysis. This was prospectively validated with a subsequent cohort of patients admitted to the ICUs during the following time period of January-September 2012. Seventy-six patients with nosocomial RGNB Infection (31bacteremia) were compared with 1398 patients with Systemic Inflammatory Response Syndrome (SIRS) without any gram negative bacterial infection/colonization admitted to the ICUs during the study period. The following independent risk factors were obtained by a multivariable logistic regression analysis - prior isolation of Gram negative organism (coeff: 1.1, 95% CI 0.5-1.7); Surgery during current admission (coeff: 0.69, 95% CI 0.2-1.2); prior Dialysis with end stage renal disease (coeff: 0.7, 95% CI 0.1-1.1); prior use of Carbapenems (coeff: 1.3, 95% CI 0.3-2.3) and Stay in the ICU for more than 5 days (coeff: 2.4, 95% CI 1.6-3.2). It was validated prospectively in a subsequent cohort (n = 408) and the area-under-the-curve (AUC) of the GSDCS score for predicting nosocomial ICU acquired RGNB infection and bacteremia was 0.77 (95% CI 0.68-0.89 and 0.78 (95% CI 0.69-0.89) respectively. The GSDCS (0-4.3) score clearly differentiated the low (0-1.3), medium (1.4-2.3) and high (2.4-4.3) risk patients, both for RGNB infection (p:0.003) and bacteremia (p:0.009). GSDCS is a simple bedside clinical score which predicts RGNB infection and bacteremia with high predictive value and differentiates low versus high risk patients. This score will help clinicians to choose appropriate, timely targeted antibiotic therapy and avoid exposure to unnecessary treatment for patients at low risk of nosocomial RGNB infection. This will reduce the selection pressure and help to contain antibiotic resistance in ICUs.

Infectious peritonitis profile in peritoneal dialysis at Ibn Sina University Hospital: a 6-year data report.

PubMed

Bekaoui, Samira; Haddiya, Intissar; Houti, Maria Slimani; Berkchi, Fatima Zahra; Ezaitouni, Fatima; Ouzeddoun, Naima; Bayahia, Rabia; Benamar, Loubna

2014-01-01

Infectious peritonitis (IP) is the most common complication in peritoneal dialysis (PD). The purpose of this study is to assess the prevalence of IP and to determine its clinical, biological, and evolutive characteristics. We conducted a five year, five months retrospective study from July 2006 to December 2011. All patients on peritoneal dialysis that have been followed on PD for a minimum of 3 months and who presented IP during follow-up were included. Data were analyzed using SPSS 17.0. The 76 episodes of IP were identified in 36 patients. The peritonitis rate (months × patients/peritonitis), as calculated by the Registre de Dialyse Péritonéale de Langue Française (RDPLF Registry) [French peritoneal dialysis registry] in December 2011, was 18.59. Time to occurrence of peritonitis from the start of peritoneal exchange was 15.44±10 months. The mean age of our patients was 49.1±16.8 years [10-80]: the youngest patient's age was 10, while the oldest was 80 years old (male to female: sex ratio M/F=1,66). Also, 22% of our patients were diabetic. The mean follow-up in PD was 22.6±14 months. Abdominal pain was present in 79% of the cases. Fever and vomiting were noted in 42% and 38% of cases, respectively. The C-reactive protein rate was elevated in 77% of cases, and leukocytosis was found in 27% of cases. Bacteriological proof was present in 73.68% of cases. Gram-positive cocci were involved in 56.6% of microbiologically proven IP cases. Gram-negative bacilli were represented in 37.7%. The outcome was favorable in 89.4%. The PD catheter was removed in 2.63% of the cases. In addition, 7.89% of our patients were transferred to hemodialysis. The rate of IP remains high in our series. More than one-half of the peritonitis cases with positive cultures (56.6%) were caused by Gram-positive cocci. Gram-negative bacilli ranked second (27.7%). These results agree with data in the literature. Moreover, the rate of culture-negative IP in our series is high (26%). Evolution is good in most cases (89%). Despite the gradual decrease of its rate, peritonitis remains frequent in our center and calls for optimization of means of prevention. The high frequency of negative culture IP in our study urges us toward better collaboration with biologists to target antibiotic therapy and improve IP management.

Spectrum of systemic bacterial infections during febrile neutropenia in pediatric oncology patients in tertiary care pediatric center.

PubMed

Siddaiahgari, Sirisharani; Manikyam, A; Kumar, K Anand; Rauthan, A; Ayyar, R

2014-01-01

Outcome of pediatric cancers has significantly improved with modern chemotherapy and good supportive care. However, febrile neutropenia remains one of the important limiting factors in these patients especially with the emergence of resistant organisms. Choosing appropriate antimicrobials is possible only if we understand the local microbial spectrum and their sensitivity pattern. To study the likely etiologic agents and their antibiotic sensitivity pattern among systemic infections in children with cancer. This is a prospective study. The study was conducted at a tertiary care center for pediatrics, in which culture samples representing blood stream infections and others like urinary tract infections sent from the Oncology services of the Hospital during the year of 2013 were analyzed. The microbiological profile and antibiotic sensitivity pattern of these isolates were studied. There were 89 isolates that represented blood and urinary tract infections in neutropenic patients with cancer.Out of 89 positive cultures 76 were gram negative isolates. The most common gram negative bacterial isolates were Escherichia coli 33 (37%), followed by Pseudomonas 21 (23.5%). Acinetobacter grew in 2 patients (2.2%). Extended spectrum beta-lactamases (ESBL's), carbepenem resistant and pan-resistant organisms seen in 28 (31.4%), 5 (5.6%) and 2 cases (2.3%) respectively. Over all Gram-positive organisms were 13/89 (12.3%). Staphylococcus was the most common Gram-positive organism and methicillin resistant Staphylococcus aureus seen in 5 each. Gram-negative organism is a common isolate in cancer children with febrile neutropenia, which is resistant to first-line antibiotic cefepime. Meropenem is most sensitive antibiotic and ESBL's are sensitive to piperacillin-tazobactam.

Nitrofurantoin safety and effectiveness in treating acute uncomplicated cystitis (AUC) in hospitalized adults with renal insufficiency: antibiotic stewardship implications.

PubMed

Cunha, B A; Cunha, C B; Lam, B; Giuga, J; Chin, J; Zafonte, V F; Gerson, S

2017-07-01

Nitrofurantoin remains a key oral antibiotic stewardship program (ASP) option in the treatment of acute uncomplicated cystitis (AUC) due to multi-drug resistant (MDR) Gram negative bacilli (GNB). However, there have been concerns regarding decreased nitrofurantoin efficacy with renal insufficiency. In our experience over the past three decades, nitrofurantoin has been safe and effective in treating AUC in hospitalized adults with renal insufficiency. Accordingly, we retrospectively reviewed our recent experience treating AUC in hospitalized adults with decreased renal function (CrCl < 60 ml/min) with nitrofurantoin. Excluded were complicated urinary tract infections. Urinary isolated susceptibility testing was done by micro broth dilution (MBD). Treatment duration was 5-7 days. Cure was defined as eradication of the uropathogen and failure was defined as minimal/no decrease in urine colony counts. Of 26 evaluable patients with renal insufficiency (CrCl < 60 ml/min), nitrofurantoin eradicated the uropathogen in 18/26 (69%) of patients, and failed in 8/26 (31%). Of the eight failures, five were due to intrinsically resistant uropathogens, e.g., Proteus sp., and one failure was related to an alkaline urine. Of the treatment failures, only two were due to renal insufficiency, i.e., CrCl < 30 ml/min. Since there are few oral antibiotics available to treat AUC due to MDR GNB uropathogens, these results have important ASP implications. Currently, nitfurantoin is not recommended if CrCl < 60 ml/min. In our experience, used appropriately against susceptible uropathogens, nitrofurantoin was highly effective in nearly all patients with CrCl = 30-60 ml/min., and only failed in two patients due to renal insufficiency (CrCl < 30 ml/ml).

In Vivo Bioluminescent Monitoring of Therapeutic Efficacy and Pharmacodynamic Target Assessment of Antofloxacin against Escherichia coli in a Neutropenic Murine Thigh Infection Model.

PubMed

Zhou, Yu-Feng; Tao, Meng-Ting; He, Yu-Zhang; Sun, Jian; Liu, Ya-Hong; Liao, Xiao-Ping

2018-01-01

Antimicrobial resistance among uropathogens has increased the rates of infection-related morbidity and mortality. Antofloxacin is a novel fluoroquinolone with broad-spectrum antibacterial activity against urinary Gram-negative bacilli, such as Escherichia coli This study monitored the in vivo efficacy of antofloxacin using bioluminescent imaging and determined pharmacokinetic (PK)/pharmacodynamic (PD) targets against E. coli isolates in a neutropenic murine thigh infection model. The PK properties were determined after subcutaneous administration of antofloxacin at 2.5, 10, 40, and 160 mg/kg of body weight. Following thigh infection, the mice were treated with 2-fold-increasing doses of antofloxacin from 2.5 to 80 mg/kg administered every 12 h. Efficacy was assessed by quantitative determination of the bacterial burdens in thigh homogenates and was compared with the bioluminescent density. Antofloxacin demonstrated both static and killing endpoints in relation to the initial burden against all study strains. The PK/PD index area under the concentration-time curve (AUC)/MIC correlated well with efficacy ( R 2 = 0.92), and the dose-response relationship was relatively steep, as observed with escalating doses of antofloxacin. The mean free drug AUC/MIC targets necessary to produce net bacterial stasis and 1-log 10 and 2-log 10 kill for each isolate were 38.7, 66.1, and 147.0 h, respectively. In vivo bioluminescent imaging showed a rapid decrease in the bioluminescent density at free drug AUC/MIC exposures that exceeded the stasis targets. The integration of these PD targets combined with the results of PK studies with humans will be useful in setting optimal dosing regimens for the treatment of urinary tract infections due to E. coli . Copyright © 2017 American Society for Microbiology.

Evaluation of the in vitro growth of urinary tract infection-causing gram-negative and gram-positive bacteria in a proposed synthetic human urine (SHU) medium.

PubMed

Ipe, Deepak S; Ulett, Glen C

2016-08-01

Bacteriuria is a hallmark of urinary tract infection (UTI) and asymptomatic bacteriuria (ABU), which are among the most frequent infections in humans. A variety of gram-negative and gram-positive bacteria are associated with these infections but Escherichia coli contributes up to 80% of cases. Multiple bacterial species including E. coli can grow in human urine as a means to maintain colonization during infections. In vitro bacteriuria studies aimed at modeling microbial growth in urine have utilized various compositions of synthetic human urine (SHU) and a Composite SHU formulation was recently proposed. In this study, we sought to validate the recently proposed Composite SHU as a medium that supports the growth of several bacterial species that are known to grow in normal human urine and/or artificial urine. Comparative growth assays of gram-negative and gram-positive bacteria E. coli, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus agalactiae, Staphylococcus saprophyticus and Enterococcus faecalis were undertaken using viable bacterial count and optical density measurements over a 48h culture period. Three different SHU formulations were tested in various culture vessels, shaking conditions and volumes and showed that Composite SHU can support the robust growth of gram-negative bacteria but requires supplementation with 0.2% yeast extract to support the growth of gram-positive bacteria. Experiments are also presented that show an unexpected but major influence of P. mirabilis towards the ability to measure bacterial growth in generally accepted multiwell assays using absorbance readings, predicted to have a basis in the release of volatile organic compound(s) from P. mirabilis during growth in Composite SHU medium. This study represents an essential methodological validation of a more chemically defined type of synthetic urine that can be applied to study mechanisms of bacteriuria and we conclude will offer a useful in vitro model to investigate the basis of some of the most common infections of humans. Copyright © 2016 Elsevier B.V. All rights reserved.

Serum bactericidal activities of moxifloxacin and levofloxacin against aerobic and anaerobic intra-abdominal pathogens.

PubMed

Stein, Gary E; Schooley, Sharon; Tyrrell, Kerin L; Citron, Diane M; Nicolau, David P; Goldstein, Ellie J C

2008-02-01

We studied the serum bactericidal activity (SBA) of moxifloxacin and levofloxacin against common pathogens associated with complicated intra-abdominal infections. Ten healthy volunteers received a single dose of moxifloxacin (400 mg) and levofloxacin (750 mg) and serum samples were collected at 2, 4, 8, 12, and 24h after the dose of each drug. Bactericidal titers in serum over time were determined for aerobic gram-negative bacilli (Escherichia coli, Klebseilla pneumoniae, and Enterobacter cloacae) and anaerobic bacteria (Bacteroides fragilis, Bacteroides thetaiotaomicron, Prevotella bivia, and Finegoldia magna). Both fluoroquinolones provided rapid (2h) attainment and prolonged (24h) SBA (titers > or = 1:8) against each of the aerobic bacilli studied. SBA was observed for at least 12h against B. fragilis strains with MICs < or = 2 microg/ml to moxifloxacin and < or = 4 microg/ml to levofloxacin. Prolonged (12h) SBA (titers > or = 1:2) was also observed against isolates of B. thetaiotaomicron, P. bivia, and F. magna with moxifloxacin < or = MICs 2 microg/ml.

Simplified Protocol for Carba NP Test for Enhanced Detection of Carbapenemase Producers Directly from Bacterial Cultures.

PubMed

Pasteran, Fernando; Tijet, Nathalie; Melano, Roberto G; Corso, Alejandra

2015-12-01

We compared carbapenemase detection among 266 Gram-negative bacilli (161 carbapenemase producers) using the Carba NP tests issued by the CLSI (CNPt-CLSI) and a novel protocol (CNPt-direct) designed for carbapenemase detection direct from bacterial cultures (instead of bacterial extracts required by the CLSI tests). The specificities were comparable (100%), but the CNPt-direct was more sensitive (98% versus 84%). The CNPt-direct was easier to perform due to the direct use of colonies and offered a more robust detection of carbapenemase producers. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Rapid Identification of OXA-48 and OXA-163 Subfamilies in Carbapenem-Resistant Gram-Negative Bacilli with a Novel Immunochromatographic Lateral Flow Assay.

PubMed

Pasteran, Fernando; Denorme, Laurence; Ote, Isabelle; Gomez, Sonia; De Belder, Denise; Glupczynski, Youri; Bogaerts, Pierre; Ghiglione, Barbara; Power, Pablo; Mertens, Pascal; Corso, Alejandra

2016-11-01

We assessed a novel immunochromatographic lateral flow assay for direct identification of OXA-48-like carbapenemases and accurate differentiation of allele variants with distinct substrate profiles (OXA-48 or OXA-163 subfamilies). The assay allowed rapid (less than 4 min) and reliable direct confirmation of OXA-163- and/or OXA-48-like enzymes (with 100% sensitivity and 100% specificity) from cultured colonies that were recovered from both solid medium and spiked blood culture bottles. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

[Influence of serious infections due to Gram-negative bacteria on the hospital economy].

PubMed

Martínez, B; Gómez, J; Gómez Vargas, J; Guerra, B; Ruiz Gómez, J; Simarro, E; Baños, V; Canteras, M; Valdes, M

2000-12-01

Nosocomial infections due to Gram-negative bacteria are very important since they are associated with high morbidity and high hospital costs. A prospective study of 250 inpatients was carried out, 200 of whom had Gram-negative bacterial infections. Patients were divided into groups of 50 according to the localization of the infection (urinary, surgical wound, respiratory tract and bacteremia), with a control group of 50 patients with similar characteristics but no infection. We calculated the cost for the different groups by multiplying the average length of hospital stay in days by the daily cost of the stay. Significant differences were observed in the average length of stay per patient according to the type of infection and how it was acquired. In terms of cost, nosocomial infection due to Gram-negative bacteria was 1,049,139 pesetas more expensive than community-acquired infection. The cost of the stay for patients with postsurgical infection due to Gram-negative bacteria was 1,108, 252 pesetas more expensive than for the group of control patients. Nosocomial infection due to Gram-negative bacteria is associated with a prolongation in hospital stay of 9 to 28 days, which is the factor that most reflects the cost that can be attributed to nosocomial infection. Consensual and protocolized measures which allow for better clinical management need to be developed.

Identification of urinary tract pathogens after 3-hours urine culture by MALDI-TOF mass spectrometry.

PubMed

Haiko, Johanna; Savolainen, Laura E; Hilla, Risto; Pätäri-Sampo, Anu

2016-10-01

Complicated urinary tract infections, such as pyelonephritis, may lead to sepsis. Rapid diagnosis is needed to identify the causative urinary pathogen and to verify the appropriate empirical antimicrobial therapy. We describe here a rapid identification method for urinary pathogens: urine is incubated on chocolate agar for 3h at 35°C with 5% CO2 and subjected to MALDI-TOF MS analysis by VITEK MS. Overall 207 screened clinical urine samples were tested in parallel with conventional urine culture. The method, called U-si-MALDI-TOF (urine short incubation MALDI-TOF), showed correct identification for 86% of Gram-negative urinary tract pathogens (Escherichia coli, Klebsiella pneumoniae, and other Enterobacteriaceae), when present at >10(5)cfu/ml in culture (n=107), compared with conventional culture method. However, Gram-positive bacteria (n=28) were not successfully identified by U-si-MALDI-TOF. This method is especially suitable for rapid identification of E. coli, the most common cause of urinary tract infections and urosepsis. Turnaround time for identification using U-si-MALDI-TOF compared with conventional urine culture was improved from 24h to 4-6h. Copyright © 2016 Elsevier B.V. All rights reserved.

Antimicrobial susceptibility of Gram-negative ESKAPE pathogens isolated from hospitalized patients with intra-abdominal and urinary tract infections in Asia-Pacific countries: SMART 2013-2015.

PubMed

Karlowsky, James A; Hoban, Daryl J; Hackel, Meredith A; Lob, Sibylle H; Sahm, Daniel F

2017-01-01

Gram-negative ESKAPE pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) are responsible for increases in antimicrobial-resistant infections worldwide. We determined in vitro susceptibilities to eight parenteral antimicrobial agents using Clinical and Laboratory Standards Institute broth microdilution methodology for Gram-negative ESKAPE pathogens isolated from hospitalized patients with intra-abdominal infections (IAIs) (n=3052) and urinary tract infections (UTIs) (n=1088) in 11 Asia-Pacific countries/regions from 2013 to 2015. Amikacin (98.3, 96.4 %), imipenem (97.1, 95.5 %) and ertapenem (95.3, 93.2 %) demonstrated the highest rates of susceptibility for isolates of K. pneumoniae from IAI and UTI, respectively, whereas susceptibility to advanced-generation cephalosporins was <84 and <71 %, respectively. K. pneumoniae with an extended-spectrum β-lactamase-positive phenotype were more common in UTI (27.1 %) than IAI (16.2 %). Imipenem and amikacin were the most active agents against extended-spectrum β-lactamase-positive K. pneumoniae from IAI (95.1, 91.8 %) and UTI (94.9, 92.3 %), respectively, whereas <54 % were susceptible to piperacillin-tazobactam. Against Enterobacter spp. and P. aeruginosa, amikacin demonstrated the highest rates of susceptibility for isolates from IAI (99.7, 95.5 %) and UTI (90.9, 91.5 %), respectively. K. pneumoniae, Enterobacter spp. and P. aeruginosa from urine demonstrated lower susceptibility to levofloxacin (74.1, 81.8 and 73.8 %) than from IAI (87.6, 91.8 and 85.4 %). For A. baumannii, rates of susceptibility to all agents tested were <43 %. We conclude that the studied Gram-negative ESKAPE pathogens demonstrated reduced susceptibility to commonly prescribed advanced-generation cephalosporins, piperacillin-tazobactam and levofloxacin, while amikacin and carbapenems were the most active. Ongoing surveillance to monitor evolving resistance trends and the development of novel antimicrobial agents with potent activity against Gram-negative ESKAPE pathogens are mandatory.

Direct detection of Streptococcus mutans in human dental plaque by polymerase chain reaction.

PubMed

Igarashi, T; Yamamoto, A; Goto, N

1996-10-01

Streptococcus mutans is an etiological agent in human dental caries. A method for the detection of S. mutans directly from human dental plaque by polymerase chain reaction has been developed. Oligonucleotide primers specific for a portion of the dextranase gene (dexA) of S. mutans Ingbritt (serotype c) were designed to amplify a 1272-bp DNA fragment by polymerase chain reaction. The present method specifically detected S. mutans (serotypes c, e and f), but none of the other mutans streptococci: S. cricetus (serotype a), S. rattus (serotype b), S. sobrinus (serotypes d and g), and S. downei (serotype h), other gram-positive bacteria (16 strains of 12 species of cocci and 18 strains of 12 species of bacilli) nor gram-negative bacteria (1 strain of 1 species of cocci and 20 strains of 18 species of bacilli). The method was capable of detecting 1 pg of the chromosomal DNA purified from S. mutans Ingbritt and as few as 12 colony-forming units of S. mutans cells. The S. mutans cells in human dental plaque were also directly detected. Seventy clinical isolates of S. mutans isolated from the dental plaque of 8 patients were all positive by the polymerase chain reaction. These results suggest that the dexA polymerase chain reaction is suitable for the specific detection and identification of S. mutans.

Systemic Edwardsiella tarda infection in a Western African lungfish (Protopterus annectens) with cytologic observation of heterophil projections.

PubMed

Rousselet, Estelle; Stacy, Nicole I; Rotstein, David S; Waltzek, Tom B; Griffin, Matt J; Francis-Floyd, Ruth

2018-06-08

This report describes a case of systemic bacterial infection caused by Edwardsiella tarda in a Western African lungfish (Protopterus annectens) exposed to poor environmental and husbandry conditions. The fish presented with a large, external ulcerative lesion and died 2 weeks after developing anorexia. Histological evaluation revealed multifocal areas of necrosis and heterophilic and histiocytic inflammation throughout multiple tissues. Gram stain identified small numbers of intra- and extracellular monomorphic Gram-negative 1 to 2 μm rod-shaped bacilli. Cytology of lung granuloma, kidney and testes imprints identified heterophilic inflammation with phagocytosis of small monomorphic bacilli and some heterophils exhibiting cytoplasmic projections indicative of heterophil extracellular traps (HETs). Initial phenotypic analysis of isolates from coelomic fluid cultures identified E. tarda. Subsequent molecular analysis of spleen, liver and intestine DNA using an E. tarda-specific endpoint PCR assay targeting the bacterial fimbrial subunit yielded a 115 bp band. Sequencing and BLASTN search revealed the sequence was identical (76/76) to E. tarda strain FL95-01 (GenBank acc. CP011359) and displayed 93% sequence identity (66/71) to Edwardsiella hoshinae strain ATCC 35051 (GenBank acc. CP011359). This is the first report of systemic edwardsiellosis in a lungfish with concurrent cytologically identified structures suggestive of HETs. © 2018 John Wiley & Sons Ltd.

[Clinical analysis for patients with continuous ambulatory peritoneal dialysis associated peritonitis].

PubMed

Liu, Jian; Huang, Xun; Liu, Yao; Xu, Hui; Gong, Rui'e; Li, Chunhui

2016-12-28

To analyze the clinical characteristics of continuous ambulatory peritoneal dialysis (CAPD) associated peritonitis in the tertiary hospitals and to discuss the preventive and therapeutic strategy.
 Methods: The clinical characteristics, pathogens, resistance and outcomes of 126 CAPD associated peritonitis in 104 patients from Jan, 2013 to June, 2016, were retrospectively analyzed.
 Results: Among the patients, the incidence rates of abdominal pain, fever, diarrhea and emesis were 104 (82.54%), 56 (44.44%), 49 (38.89%), and 31 (23.60%), respectively. Among them, 88 patients suffered peritonitis once, other 16 patients suffered multiple peritonitis or recurrent peritonitis for 38 times. Among the 38 times, the numbers for recurrent, repeated or catheter-associated peritonitis were 2, 2, or 3, respectively. Peritoneal fluids from 103 cases were cultured, and 64 cases were positive in bacteria, with a rate of 62.14%. A total of 70 strains of bacteria were separated, including 42 strains of gram-positive bacteria, 21 strains of gram-negative bacteria, and 7 strains of fungus. The most common gram-positive pathogens were Staphylococcus epidermidis, Enterococcus faecalis and Staphylococcus haemolyticus, while Escherichia coli, Klebsiella pneumoniae and Klebsiella pneumoniae were the most common gram-negative bacteria. Candida albicans was the major fungal pathogens. Gram-positive cocci showed resistance to gentamycin, levofloxacin, moxifloxacin, vancomycin and linezolid, with a rate at 20.00%, 36.11%, 5%, 0%, and 0%, respectively. The gram-negative bacilli were resistent to cefoperazone/sulbactam, gentamycin, cephazolin, and ceftazidime, with a rate at 6.25%, 10.53%, 64.29%, and 15.38%, respectively. There were no imipenem, amikacin, piperacillin/tazobactam-resistant strains were found.
 Conclusion: The most common pathogen causing CAPD associated peritonitis is gram-positive bacteria. It is crucial to take the anti-infection therapy for CAPD associated peritonitis early. The positive rates for bacterial culture need to be enhanced through improvement of methods. At the same time, doctors could improve the outcome of CAPD associated peritonitis by adjusting the medication according to the drug sensitivity results.

Prosthetic joint infection caused by Trueperella bernardiae.

PubMed

Gilarranz, Raul; Chamizo, Francisco; Horcajada, Iballa; Bordes-Benítez, Ana

2016-09-01

Trueperella bernardiae is a Gram-positive coryneform bacilli which role as human pathogen is unknown because it has been usually considered a contaminant. Furthermore its identification by biochemical test was difficult. We describe a prosthetic joint infection in a women who years ago underwent a total knee replacement with superinfection and necrosis of the patellar tendon as major complications. In the sample of synovial fluid collected grew a gram-positive bacilli which was identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) as T. bernardiae. The patient was treated with ciprofloxacin and currently preserves the prosthesis without signs of infection. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Etiology of Bacteremia in Young Infants in Six Countries

PubMed Central

Darmstadt, Gary L.; Carlin, John B.; Zaidi, Anita K. M.; Yeboah-Antwi, Kojo; Saha, Samir K.; Ray, Pallab; Narang, Anil; Mazzi, Eduardo; Kumar, Praveen; Kapil, Arti; Jeena, Prakash M.; Deorari, Ashok; Chowdury, A.K. Azad; Bartos, Andrés; Bhutta, Zulfiqar A.; Adu-Sarkodie, Yaw; Adhikari, Miriam; Addo-Yobo, Emmanuel; Weber, Martin W.

2015-01-01

Background: Neonatal illness is a leading cause of death worldwide; sepsis is one of the main contributors. The etiologies of community-acquired neonatal bacteremia in developing countries have not been well characterized. Methods: Infants <2 months of age brought with illness to selected health facilities in Bangladesh, Bolivia, Ghana, India, Pakistan and South Africa were evaluated, and blood cultures taken if they were considered ill enough to be admitted to hospital. Organisms were isolated using standard culture techniques. Results: Eight thousand eight hundred and eighty-nine infants were recruited, including 3177 0–6 days of age and 5712 7–59 days of age; 10.7% (947/8889) had a blood culture performed. Of those requiring hospital management, 782 (54%) had blood cultures performed. Probable or definite pathogens were identified in 10.6% including 10.4% of newborns 0–6 days of age (44/424) and 10.9% of infants 7–59 days of age (39/358). Staphylococcus aureus was the most commonly isolated species (36/83, 43.4%) followed by various species of Gram-negative bacilli (39/83, 46.9%; Acinetobacter spp., Escherichia coli and Klebsiella spp. were the most common organisms). Resistance to second and third generation cephalosporins was present in more than half of isolates and 44% of the Gram-negative isolates were gentamicin-resistant. Mortality rates were similar in hospitalized infants with positive (5/71, 7.0%) and negative blood cultures (42/557, 7.5%). Conclusions: This large study of young infants aged 0–59 days demonstrated a broad array of Gram-positive and Gram-negative pathogens responsible for community-acquired bacteremia and substantial levels of antimicrobial resistance. The role of S. aureus as a pathogen is unclear and merits further investigation. PMID:25389919

Etiology of bacteremia in young infants in six countries.

PubMed

Hamer, Davidson H; Darmstadt, Gary L; Carlin, John B; Zaidi, Anita K M; Yeboah-Antwi, Kojo; Saha, Samir K; Ray, Pallab; Narang, Anil; Mazzi, Eduardo; Kumar, Praveen; Kapil, Arti; Jeena, Prakash M; Deorari, Ashok; Chowdury, A K Azad; Bartos, Andrés; Bhutta, Zulfiqar A; Adu-Sarkodie, Yaw; Adhikari, Miriam; Addo-Yobo, Emmanuel; Weber, Martin W

2015-01-01

Neonatal illness is a leading cause of death worldwide; sepsis is one of the main contributors. The etiologies of community-acquired neonatal bacteremia in developing countries have not been well characterized. Infants <2 months of age brought with illness to selected health facilities in Bangladesh, Bolivia, Ghana, India, Pakistan and South Africa were evaluated, and blood cultures taken if they were considered ill enough to be admitted to hospital. Organisms were isolated using standard culture techniques. Eight thousand eight hundred and eighty-nine infants were recruited, including 3177 0-6 days of age and 5712 7-59 days of age; 10.7% (947/8889) had a blood culture performed. Of those requiring hospital management, 782 (54%) had blood cultures performed. Probable or definite pathogens were identified in 10.6% including 10.4% of newborns 0-6 days of age (44/424) and 10.9% of infants 7-59 days of age (39/358). Staphylococcus aureus was the most commonly isolated species (36/83, 43.4%) followed by various species of Gram-negative bacilli (39/83, 46.9%; Acinetobacter spp., Escherichia coli and Klebsiella spp. were the most common organisms). Resistance to second and third generation cephalosporins was present in more than half of isolates and 44% of the Gram-negative isolates were gentamicin-resistant. Mortality rates were similar in hospitalized infants with positive (5/71, 7.0%) and negative blood cultures (42/557, 7.5%). This large study of young infants aged 0-59 days demonstrated a broad array of Gram-positive and Gram-negative pathogens responsible for community-acquired bacteremia and substantial levels of antimicrobial resistance. The role of S. aureus as a pathogen is unclear and merits further investigation.

EVALUATION OF OCULAR PROSTHESIS BIOFILM AND ANOPHTHALMIC CAVITY CONTAMINATION AFTER USE OF THREE CLEANSING SOLUTIONS

PubMed Central

Paranhos, Regina Márcia Zuccolotto Felippe; Batalhão, Carlos Henrique; Semprini, Marisa; Regalo, Simone Cecílio Hallak; Ito, Izabel Yoko; de Mattos, Maria da Glória Chiarello

2007-01-01

In addition to an initial socket discomfort, ocular prosthesis (OP) installation may allow the adherence of fungi and/or bacteria due to the superficial characteristics of the prosthesis’ material, use of inadequate cleansing solutions and methods, or because the void located between the internal portion of the prosthesis and the anophthalmic cavity (AC) mucosa. Objective: The aim of this study was to evaluate OP biofilm formation and the level of contamination of the internal portion of the OP and the AC in 24 patients. Material and Methods: Material was collected from the AC at the beginning of the study and 15 days after cleansing of the OP with 3 cleansing solutions: a neutral liquid soap, a multiuse solution for contact lens (Complete) and 0.12% chlorhexidine (Periogard). The collected materials were sowed in Petri dishes containing selective media for aerobic and facultative microorganisms, specifically staphylococci (Hipersalt agar with egg yolk), aerobic microorganisms (Brain Heart Infusion Blood Agar), streptococci (Mitis salivarius Agar), gram-negative bacilli (MacConkey Agar) and yeasts (Chromagar CandidaTM), incubated at 35°C or 37°C and the number of colony forming units were counted. Data were analyzed statistically by ANOVA, Friedman’s test and Spearman’s correlation. Results: Aerobic microorganisms, gram-negative bacilli and S. aureus were found in the OP biofilm and in the AC. There was statistically significant difference (p<0.05) between the number of microorganisms before and after the use of the cleansing solutions. Conclusion: There was positive correlation with respect to the microorganisms present in the OP biofilm and AC for the 4 proposed treatments, indicating that the decrease of OP contamination leads to AC contamination as well. PMID:19089097

10 × '20 Progress—Development of New Drugs Active Against Gram-Negative Bacilli: An Update From the Infectious Diseases Society of America

PubMed Central

Boucher, Helen W.; Talbot, George H.; Benjamin, Daniel K.; Bradley, John; Guidos, Robert J.; Jones, Ronald N.; Murray, Barbara E.; Bonomo, Robert A.; Gilbert, David

2013-01-01

Infections caused by antibiotic-resistant bacteria, especially the “ESKAPE” pathogens, continue to increase in frequency and cause significant morbidity and mortality. New antimicrobial agents are greatly needed to treat infections caused by gram-negative bacilli (GNB) resistant to currently available agents. The Infectious Diseases Society of America (IDSA) continues to propose legislative, regulatory, and funding solutions to this continuing crisis. The current report updates the status of development and approval of systemic antibiotics in the United States as of early 2013. Only 2 new antibiotics have been approved since IDSA's 2009 pipeline status report, and the number of new antibiotics annually approved for marketing in the United States continues to decline. We identified 7 drugs in clinical development for treatment of infections caused by resistant GNB. None of these agents was included in our 2009 list of antibacterial compounds in phase 2 or later development, but unfortunately none addresses the entire spectrum of clinically relevant GNB resistance. Our survey demonstrates some progress in development of new antibacterial drugs that target infections caused by resistant GNB, but progress remains alarmingly elusive. IDSA stresses our conviction that the antibiotic pipeline problem can be solved by the collaboration of global leaders to develop creative incentives that will stimulate new antibacterial research and development. Our aim is the creation of a sustainable global antibacterial drug research and development enterprise with the power in the short term to develop 10 new, safe, and efficacious systemically administered antibiotics by 2020 as called for in IDSA's “10 × '20 Initiative.” PMID:23599308

Towards a phenotypic screening strategy for emerging β-lactamases in Gram-negative bacilli.

PubMed

Willems, Elise; Verhaegen, Jan; Magerman, Koen; Nys, Sita; Cartuyvels, Reinoud

2013-02-01

The purpose of this manuscript was to review recent literature and guidelines regarding phenotypic detection of emerging β-lactamases [extended-spectrum β-lactamases (ESBLs), AmpC β-lactamases and carbapenemases] in Gram-negative bacilli (GNB) in order to formulate recommendations on best practice to screen for them. We conclude that chromogenic ESBL screening agar plates are suitable to screen for ESBL-producing Enterobacteriaceae directly from clinical samples. Furthermore, ceftazidime (CAZ) and ceftriaxone or cefotaxime (CTX) are the indicator antimicrobial agents of choice for ESBL detection in GNB. In non-inducible Enterobacteriaceae, the combined double-disk synergy test (CDDST) with at least CTX and CAZ and additionally cefepime as indicators is the preferred ESBL confirmation assay. The two most suitable ESBL confirmation strategies in AmpC co-producing Enterobacteriaceae are adapted CDDSTs: (i) with addition of 3-aminophenylboronic acid to CTX and CAZ disks; and (ii) with addition of cloxacillin (CLOX) to Mueller-Hinton agar. Reduced cefoxitin susceptibility and decreased susceptibility to cefotetan are regarded as suitable screening tests for plasmid-mediated and derepressed AmpC production. A CLOX-based CDDST with CTX and CAZ as indicators is considered to be the best AmpC confirmation assay. Finally, in Enterobacteriaceae isolates we suggest to screen for carbapenemases with a 0.5 μg/mL meropenem screening breakpoint. For class A carbapenemase confirmation, the home-prepared as well as the commercially available boronic acid-based CDDST can be considered. For metallo-β-lactamase confirmation, ethylene diamine tetra-acetic-acid-based home-prepared assays are recommended. The most suitable method (CDDST or DDST) and indicator antimicrobial agent(s) vary depending on the bacterial genus. Copyright © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Activities of fosfomycin, tigecycline, colistin, and gentamicin against extended-spectrum-β-lactamase-producing Escherichia coli in a foreign-body infection model.

PubMed

Corvec, Stéphane; Furustrand Tafin, Ulrika; Betrisey, Bertrand; Borens, Olivier; Trampuz, Andrej

2013-03-01

Limited antimicrobial agents are available for the treatment of implant-associated infections caused by fluoroquinolone-resistant Gram-negative bacilli. We compared the activities of fosfomycin, tigecycline, colistin, and gentamicin (alone and in combination) against a CTX-M15-producing strain of Escherichia coli (Bj HDE-1) in vitro and in a foreign-body infection model. The MIC and the minimal bactericidal concentration in logarithmic phase (MBC(log)) and stationary phase (MBC(stat)) were 0.12, 0.12, and 8 μg/ml for fosfomycin, 0.25, 32, and 32 μg/ml for tigecycline, 0.25, 0.5, and 2 μg/ml for colistin, and 2, 8, and 16 μg/ml for gentamicin, respectively. In time-kill studies, colistin showed concentration-dependent activity, but regrowth occurred after 24 h. Fosfomycin demonstrated rapid bactericidal activity at the MIC, and no regrowth occurred. Synergistic activity between fosfomycin and colistin in vitro was observed, with no detectable bacterial counts after 6 h. In animal studies, fosfomycin reduced planktonic counts by 4 log(10) CFU/ml, whereas in combination with colistin, tigecycline, or gentamicin, it reduced counts by >6 log(10) CFU/ml. Fosfomycin was the only single agent which was able to eradicate E. coli biofilms (cure rate, 17% of implanted, infected cages). In combination, colistin plus tigecycline (50%) and fosfomycin plus gentamicin (42%) cured significantly more infected cages than colistin plus gentamicin (33%) or fosfomycin plus tigecycline (25%) (P < 0.05). The combination of fosfomycin plus colistin showed the highest cure rate (67%), which was significantly better than that of fosfomycin alone (P < 0.05). In conclusion, the combination of fosfomycin plus colistin is a promising treatment option for implant-associated infections caused by fluoroquinolone-resistant Gram-negative bacilli.

Effect of Surotomycin, a Novel Cyclic Lipopeptide Antibiotic, on Intestinal Colonization with Vancomycin-Resistant Enterococci and Klebsiella pneumoniae in Mice

PubMed Central

Deshpande, Abhishek; Hurless, Kelly; Cadnum, Jennifer L.; Chesnel, Laurent; Gao, Lihong; Chan, Luisa; Kundrapu, Sirisha; Polinkovsky, Alexander

2016-01-01

Surotomycin (formerly called CB-183,315) is a novel, orally administered cyclic lipopeptide antibacterial in development for the treatment of Clostridium difficile infection (CDI) that has potent activity against vancomycin-resistant enterococci (VRE) but limited activity against Gram-negative bacilli, including Bacteroides spp. We used a mouse model to investigate the impact of surotomycin exposure on the microbiome, and to test the consequences of the disruption on colonization by vancomycin-resistant enterococci (VRE) and extended-spectrum β-lactamase-producing Klebsiella pneumoniae (ESBL-KP), in comparison with the effects of oral vancomycin and metronidazole. Mice (8 per group) received saline, vancomycin, metronidazole, or surotomycin through an orogastric tube daily for 5 days and were challenged with 105 CFU of VRE or ESBL-KP administered through an orogastric tube on day 2 of treatment. The concentrations of the pathogens in stool were determined during and after treatment by plating on selective media. A second experiment was conducted to determine if the antibiotics would inhibit established VRE colonization. In comparison to controls, oral vancomycin promoted VRE and ESBL-KP overgrowth in stool (8 log10 to 10 log10 CFU/g; P < 0.001), whereas metronidazole did not (<4 log10 CFU/g; P > 0.5). Surotomycin promoted ESBL-KP overgrowth (>8 log10 CFU/g; P, <0.001 for comparison with saline controls) but not VRE overgrowth. Surotomycin suppressed preexisting VRE colonization, whereas metronidazole and vancomycin did not. These results suggest that treatment of CDI with surotomycin could reduce levels of VRE acquisition and overgrowth from those with agents such as vancomycin and metronidazole. However, surotomycin and vancomycin may promote colonization by antibiotic-resistant Gram-negative bacilli. PMID:26976870

Emergence of Imipenem-Resistant Gram-Negative Bacilli in Intestinal Flora of Intensive Care Patients

PubMed Central

Angebault, Cécile; Barbier, François; Hamelet, Emilie; Defrance, Gilles; Ruppé, Etienne; Bronchard, Régis; Lepeule, Raphaël; Lucet, Jean-Christophe; El Mniai, Assiya; Wolff, Michel; Montravers, Philippe; Plésiat, Patrick; Andremont, Antoine

2013-01-01

Intestinal flora contains a reservoir of Gram-negative bacilli (GNB) resistant to cephalosporins, which are potentially pathogenic for intensive care unit (ICU) patients; this has led to increasing use of carbapenems. The emergence of carbapenem resistance is a major concern for ICUs. Therefore, in this study, we aimed to assess the intestinal carriage of imipenem-resistant GNB (IR-GNB) in intensive care patients. For 6 months, 523 consecutive ICU patients were screened for rectal IR-GNB colonization upon admission and weekly thereafter. The phenotypes and genotypes of all isolates were determined, and a case control study was performed to identify risk factors for colonization. The IR-GNB colonization rate increased regularly from 5.6% after 1 week to 58.6% after 6 weeks in the ICU. In all, 56 IR-GNB strains were collected from 50 patients: 36 Pseudomonas aeruginosa strains, 12 Stenotrophomonas maltophilia strains, 6 Enterobacteriaceae strains, and 2 Acinetobacter baumannii strains. In P. aeruginosa, imipenem resistance was due to chromosomally encoded resistance (32 strains) or carbapenemase production (4 strains). In the Enterobacteriaceae strains, resistance was due to AmpC cephalosporinase and/or extended-spectrum β-lactamase production with porin loss. Genomic comparison showed that the strains were highly diverse, with 8 exceptions (4 VIM-2 carbapenemase-producing P. aeruginosa strains, 2 Klebsiella pneumoniae strains, and 2 S. maltophilia strains). The main risk factor for IR-GNB colonization was prior imipenem exposure. The odds ratio for colonization was already as high as 5.9 (95% confidence interval [95% CI], 1.5 to 25.7) after 1 to 3 days of exposure and increased to 7.8 (95% CI, 2.4 to 29.8) thereafter. In conclusion, even brief exposure to imipenem is a major risk factor for IR-GNB carriage. PMID:23318796

Late-onset neonatal sepsis: recent developments.

PubMed

Dong, Ying; Speer, Christian P

2015-05-01

The incidence of neonatal late-onset sepsis (LOS) is inversely related to the degree of maturity and varies geographically from 0.61% to 14.2% among hospitalised newborns. Epidemiological data on very low birth weight infants shows that the predominant pathogens of neonatal LOS are coagulase-negative staphylococci, followed by Gram-negative bacilli and fungi. Due to the difficulties in a prompt diagnosis of LOS and LOS-associated high risk of mortality and long-term neurodevelopmental sequelae, empirical antibiotic treatment is initiated on suspicion of LOS. However, empirical therapy is often inappropriately used with unnecessary broad-spectrum antibiotics and a prolonged duration of treatment. The increasing number of multidrug-resistant Gram-negative micro-organisms in neonatal intensive care units (NICU) worldwide is a serious concern, which requires thorough and efficient surveillance strategies and appropriate treatment regimens. Immunological strategies for preventing neonatal LOS are not supported by current evidence, and approaches, such as a strict hygiene protocol and the minimisation of invasive procedures in NICUs represent the cornerstone to reduce the burden of neonatal LOS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Bacterial profile and drug susceptibility pattern of urinary tract infection in pregnant women at Tikur Anbessa Specialized Hospital Addis Ababa, Ethiopia.

PubMed

Assefa, Addisu; Asrat, Daniel; Woldeamanuel, Yimtubezinash; G/Hiwot, Yirgu; Abdella, Ahmed; Melesse, Tadele

2008-07-01

Urinary tract infection (UTI) is a common complication of pregnancy. It may be symptomatic or asymptomatic. The aim of this cross sectional study was to identify bacterial agents and their antibiotic susceptibility pattern isolated from pregnant women with UTI attending antenatal clinic of Tikur Anbessa Specialized Hospital (TASH). Four hundred and fourteen pregnant women with asymptomatic UTI (n = 369) and symptomatic UTI (n = 45) were investigated for urinary tract infection from January to March 2005. The age range of both groups was 18 to 44 years. Bacteriological screening of mid-stream urine specimens revealed that 39/369 (10.6%) and 9/45 (20%) had significant bacteriuria in asymptomatic and symptomatic group, respectively (p = 0.10). The overall prevalence of urinary tract infection was 48/414 (11.6%). The bacterial pathogens isolated were predominantly E. coil (44%), followed by S. aureus (20%), coagulase-negative staphylococci (16%), and K. pneumoniae (8%). Others found in small in number included P. mirabilis, P. aeruginosa, Enterococcus spp. and non-Group A-beta hemolytic Streptococcus, this accounted 2% for each. The gram positive and negative bacteria accounted 40% and 60% respectively. The susceptibility pattern for gram-negative bacteria showed that most of the isolates (> 65% of the strains) were sensitive to amoxicillin-clavulanic acid (70%), chloramphenicol (83.3%), gentamicin (93.3%), kanamycin (93.3%), nitrofurantoin (87.7%) and trimethoprim-sulphamethoxazole (73.3%). Among the gram-positives, more than 60% of the isolates were sensitive to amoxicillin-clavulanic acid (100%), cephalothin (95%), chloramphenicol (70%), erythromycin (80%), gentamicin (85%), methicillin (83.3%), nitrofurantoin (100%) and trimethoprim-sulphamethoxazole (65%). Generally, amoxicillin-clavulanic acid, chloramphenicol, gentamicin, nitrofurantoin and trimethoprim-sulphamethoxazole were effective at least in 70% of the isolates. Multiple drug resistance (resistance two or more drugs) was observed in 74% of the isolates. Significant bacteriuria was observed in both asymptomatic and symptomatic pregnant women. Periodic studies are recommended to confirm the findings of this study and also monitor any changes in the susceptibility patterns of uropathogens causing urinary tract infection in the pregnant women.

Bacterial profile and drug susceptibility pattern of urinary tract infection in pregnant women at University of Gondar Teaching Hospital, Northwest Ethiopia

PubMed Central

2012-01-01

Background Urinary tract infection (UTI) is a common health problem among pregnant women. Proper investigation and prompt treatment are needed to prevent serious life threatening condition and morbidity due to urinary tract infection that can occur in pregnant women. Recent report in Addis Ababa, Ethiopia indicated the prevalence of UTI in pregnant women was 11.6 % and Gram negative bacteria was the predominant isolates and showed multi drug resistance. This study aimed to assess bacterial profile that causes urinary tract infection and their antimicrobial susceptibility pattern among pregnant women visiting antenatal clinic at University of Gondar Teaching Hospital, Northwest Ethiopia. Methods A cross-sectional study was conducted at University of Gondar Teaching Hospital from March 22 to April 30, 2011. Mid stream urine samples were collected and inoculated into Cystine Lactose Electrolyte Deficient medium (CLED). Colony counts yielding bacterial growth of 105/ml of urine or more of pure isolates were regarded as significant bacteriuria for infection. Colony from CLED was sub cultured onto MacConkey agar and blood agar plates. Identification was done using cultural characteristics and a series of biochemical tests. A standard method of agar disc diffusion susceptibility testing method was used to determine susceptibility patterns of the isolates. Results The overall prevalence of UTI in pregnant women was 10.4 %. The predominant bacterial pathogens were Escherichia coli 47.5 % followed by coagulase-negative staphylococci 22.5 %, Staphylococcus aureus 10 %, and Klebsiella pneumoniae 10 %. Gram negative isolates were resulted low susceptibility to co-trimoxazole (51.9 %) and tetracycline (40.7 %) whereas Gram positive showed susceptibility to ceftriaxon (84.6 %) and amoxicillin–clavulanic acid (92.3 %). Multiple drug resistance (resistance to two or more drugs) was observed in 95 % of the isolates. Conclusion Significant bacteriuria was observed in asymptomatic pregnant women. Periodic studies are recommended to check the outcome of asymptomatic bacteriuria and also monitor any changes in the susceptibility patterns of urinary tract pathogens in pregnant women. PMID:22534117

[Bacteriologic study of abscesses caused by bites of snakes of the genus Bothrops].

PubMed

de Andrade, J G; Pinto, R N; de Andrade, A L; Martelli, C M; Zicker, F

1989-01-01

The bacterial flora of 99 cases of abscesses following Bothrops snakebite were analysed. They corresponded to 61.1% of all snakebite abscesses observed in 1030 patients attending the Hospital de Doenças Tropicais de Goiánia in Goiás, Brazil, from January 1984 to April 1988. An exsudate sample of each abscess was examined by Gram stain, culture and susceptibility tests. The Gram negative bacillis, Morganella morganii, Escherichia coli and Providencia sp were the most frequent bacterias isolated. They were identified in 44.4%, 20.2% and 13.1% of the samples respectively. This flora was similar to those described in snake mouth and venom by other researchers. Based on the results of the susceptibility tests the authors suggested the use of chloramphenicol for the treatment of those abscesses which do not respond to simple drainage.

Reduction in clinical response to empiric antimicrobial therapy of febrile granulocytopenic patients receiving TMP/SMX infection prophylaxis

PubMed Central

Bow, Eric J; Pater, Joseph L; Louie, Thomas J; Feld, Ronald; Mandell, Lionel; Robson, Hugh G; Chow, Anthony; Belch, Andrew; Miedzinski, Lilly; Paul, Nancy; Elliott, Catherine R; Willan, Andrew R

1992-01-01

In the course of a multicentre clinical trial evaluating two antibacterial regimens for the empiric treatment of suspected infection in febrile neutropenic cancer patients, a suboptimal response was noted among recipients of antibacterial prophylaxis with trimethoprim/sulphamethoxazole (TMP/SMX). Multivariate analysis identified TMP/SMX prophylaxis as a predictor of poor outcome independent of other variables such as classification of infection, marrow recovery, neutrophil count at first fever, indwelling central venous catheter use, and underlying disease. This effect appeared to be restricted to recipients of tobramycin plus ticarcillin (TT). TMP/SMX suppresses potentially pathogenic aerobic Gram-negative bacilli and allows colonization and subsequent infection by Gram-positive microorganisms against which TT-like regimens have limited activity. Recognition of this phenomenon may permit a more appropriate selection of antibacterial agents for the therapy of suspected infection in the neutropenic patient. PMID:22416197

Clinical factors associated with shock in bacteremic UTI.

PubMed

Shigemura, Katsumi; Tanaka, Kazushi; Osawa, Kayo; Arakawa, Sochi; Miyake, Hideaki; Fujisawa, Masato

2013-06-01

Urinary tract infection (UTI) often causes bacteremia, resulting in shock. The purpose of this study is to investigate urological bacteremia and bacteremia shock cases and seek for the clinical factors associated with urological bacteremic shock. Seventy consecutive cases with bacteremia caused by UTI from the Department of Urology, Kobe University Hospital were studied. These cases were diagnosed from 2000 to 2010 and had full data available for analysis. We investigated the potential clinical factors associated with bacteremic shock (systolic blood pressure ≤ 90 mmHg with UTI), including: (1) the number of basal general diseases (such as diabetes, malignancy, immune diseases, heart diseases, liver diseases, and kidney diseases), (2) causative bacteria, (3) antibiotics and therapeutic intervention, (4) gram-negative bacteria, (5) resistance to imipenem (which is often used in this infection), and (6) serum white blood cell counts and C-reactive protein (CRP) at the time of diagnosis of bacteremic UTI. A total of 81 causative bacteria were isolated: 42 cases were gram-negative and 39 were gram-positive bacteria. In detail, Escherichia coli was the most common, followed by Methicillin-resistant Staphylococcus aureus. The comparison data revealed that urological bacteremic shock cases had significantly increased CRP (p < 0.001). Our univariate analyses showed indwelling urinary tract catheters (p = 0.02) as a significant clinical factor associated with urological bacteremic shock and multivariate analyses showed that the presence of indwelling urinary tract catheters before UTI was a significant clinical factor associated with urological bacteremic shock (p = 0.04). Indwelling urinary catheters before UTI and high CRP were clinical factors associated with urological bacteremic shock. This result should be considered during decision-making for UTI treatments in high risk cases or urological bacteremia cases.

Discrimination of selected species of pathogenic bacteria using near-infrared Raman spectroscopy and principal components analysis

NASA Astrophysics Data System (ADS)

de Siqueira e Oliveira, Fernanda S.; Giana, Hector E.; Silveira, Landulfo, Jr.

2012-03-01

It has been proposed a method based on Raman spectroscopy for identification of different microorganisms involved in bacterial urinary tract infections. Spectra were collected from different bacterial colonies (Gram negative: E. coli, K. pneumoniae, P. mirabilis, P. aeruginosa, E. cloacae and Gram positive: S. aureus and Enterococcus sp.), grown in culture medium (Agar), using a Raman spectrometer with a fiber Raman probe (830 nm). Colonies were scraped from Agar surface placed in an aluminum foil for Raman measurements. After pre-processing, spectra were submitted to a Principal Component Analysis and Mahalanobis distance (PCA/MD) discrimination algorithm. It has been found that the mean Raman spectra of different bacterial species show similar bands, being the S. aureus well characterized by strong bands related to carotenoids. PCA/MD could discriminate Gram positive bacteria with sensitivity and specificity of 100% and Gram negative bacteria with good sensitivity and high specificity.

Phenotypic and genotypic characterization of Klebsiella pneumonia recovered from nonhuman primates

USDA-ARS?s Scientific Manuscript database

Klebsiella pneumoniae is a zoonotic, Gram-negative member of the family Enterobacteriaceae and is the causative agent of nosocomial septicemic, pneumonic, and urinary tract infections. Recently, pathogenic strains of K. pneumoniae sharing a hypermucoviscosity (HMV) phenotype have been attributed to ...

Antimicrobial Activity of a Novel Vascular Access Film Dressing Containing Chlorhexidine Gluconate

PubMed Central

Wibaux, Anne; Thota, Priyaleela; Mastej, Jozef; Prince, Daniel L.; Carty, Neal; Johnson, Peter

2015-01-01

Background Covering insertion sites with chlorhexidine impregnated dressings has been proven to be clinically effective in reducing catheter related blood stream infections (CR-BSI). Two chlorhexidine gluconate (CHG)-impregnated dressings are commercially available, a polyurethane foam disk and a film dressing containing a chlorhexidine gluconate-impregnated gel pad. While both have demonstrated efficacy in clinical settings, the major drawback of high cost and impaired IV insertion site visibility limits their usage. A new, simple film dressing containing CHG within its adhesive layer is now available. The objective of this study was to test the in vitro antimicrobial efficacy of the new dressing in comparison to the CHG-impregnated gel dressing. Methods Quantitative aliquots of suspensions (concentration of 1.0x106 to 5.0x106 cfu/sample) of clinically relevant challenge organisms (Staphylococcus species, gram-negative bacilli, Candida albicans) were incubated in contact with the new CHG-containing film dressing, a placebo version of the same (negative control) and the commercially available CHG-impregnated gel dressing (positive control). Serial dilutions of the surviving organisms were quantified using the pour plate after 1, 3, 5, and 7 days of incubation in order to calculate an antimicrobial log10 reduction for each organism/dressing combination at each point in time. Results The new CHG-containing film dressing delivered greater than 5.0 log10 reduction throughout the 7 days on all aerobic gram-negative bacilli and Staphylococcus species tested. As of day 1 the CHG-containing film dressing provided greater than 5.0 log10 reduction on Candida albicans. There were no statistically significant differences in the log10 reduction between the two dressings tested. Conclusion The new CHG-containing film dressing was found to be as effective as the chlorhexidine gluconate-impregnated gel dressing on clinically relevant microbes. PMID:26599087

Evaluation of the Sysmex UF1000i flow cytometer for ruling out bacterial urinary tract infection.

PubMed

De Rosa, Rita; Grosso, Shamanta; Bruschetta, Graziano; Avolio, Manuela; Stano, Paola; Modolo, Maria Luisa; Camporese, Alessandro

2010-08-05

Urine culture is one of the most frequently requested tests in microbiology, and it represents the gold standard for the diagnosis of UTIs. Considering the high prevalence of negative results and the long TAT of the culture test, the use of a rapid and reliable screening method is becoming more and more important, as it reduces the workload, the TAT of negative results, and above all, unnecessary antibiotic prescription. The Sysmex UF1000i is a new urine flow cytometry analyzer capable of quantifying urinary particles, including BACT, WBCs, and YLCs. To evaluate the analytical performance of the UF1000i as a method for ruling out UTIs, we examined 1349 urine samples and compared the UF1000i results with standard urine culture results. With instrument cut-off values of 170BACTx10(6)/L and 150WBCsx10(6)/L, we obtained a sensitivity of 98.8%, a specificity of 76.5%, a NPV of 99.5%, and four false negative results (1.2%), avoiding the culture of 57.1% of samples. The Sysmex UF1000i was capable of improving the efficiency of a routine microbiology laboratory by processing 100samples/h and providing negative results in a few minutes, thus reducing unnecessary testing with an acceptable number of false negative results. In addition, the preliminary evaluation of B_FSC and B_FLH parameters from bacteria histograms seems to be useful for the distinction of bacterial strains detected (Gram-negatives versus Gram-positives). In fact when B_FSC was less than 30 ch, it allowed the distinction of Gram-negative bacteria in 97% of the samples. Copyright 2010 Elsevier B.V. All rights reserved.

Micro-Raman spectroscopy for identification and classification of UTI bacteria

NASA Astrophysics Data System (ADS)

Yogesha, M.; Chawla, Kiran; Acharya, Mahendra; Chidangil, Santhosh; Bankapur, Aseefhali

2017-07-01

Urinary tract infection (UTI) is one of the major clinical problems known to mankind, especially among adult women. Conventional methods for identification of UTI causing bacteria are time consuming and expensive. Therefore, a rapid and cost-effective method is desired. In the present study, five bacteria (one Gram-positive and four Gram-negative), most commonly known to cause UTI, have been identified and classified using micro-Raman spectroscopy combined with principal component analysis (PCA).

CHANGES IN THE MICROFLORA OF HADDOCK FILLETS AND SHUCKED SOFT-SHELLED CLAMS AFTER IRRADIATION WITH Co$sup 60$ GAMMA RAYS AND STORAGE TO 0 C AND 6 C

DOE Office of Scientific and Technical Information (OSTI.GOV)

Masurovsky, E.B.; Voss, J.S.; Goldblith, S.A.

1963-05-01

Microbiologic analyses were made on haddock fillets and shucked soft- shelled clams before and after treatment with doses of from 50000 to 800000 rad of Co/sup 60/ gamma rays. A decided change occurred in the constitution of the microbial populations of both products: from a mixed gram-negativegram-positive flora to a predominantly gram-positive flora immediately after irradiation. The majority of these surviving microorganisms were micrococci, spore-forming bacilli, yeasts, molds, and actinomyces. During storage at refrigeration temperatures above freezing, the microflora changed from the more radioresistant gram-positive species to the more prolific gram-negative psychrophilic species that flourish at low temperatures. Micrococci andmore » gram-positive rods declined somewhat during the rise of the actively proteolytic-lipolytic pseudomonads and related species, but still remained at high enough levels to contribute significantly to the spoilage observed at different times in storage. The eventual spoilage of haddock fillets was characterized by discoloration with water-soluble yellow, green, and red bacterial pigments; degradation of the tissue, by proteolytic and other microbial enzymes; and formation of volatile compounds that smelled putrid, rancid, and generally foul and pungent. Shucked soft-shelled clams displayed a different spoilage pattern, changing to a gelatinous mass with stale, acrid, putrid, sulfurous odor. These differences are attributable to the varied biochemical nature of the tissues involved, the Eh potential within the tissues, the time sequence of microfloral change, and the species and types of microorganisms associated with each product. Staphylococci were present in small numbers, but did not appear to be species of public health significance. Gram-negative enteric rods were also encountered, but were considered to be of doubtful public health importance. (BBB)« less

Hyperammoniemic coma in a patient with ureterosigmoidostomy and normal liver function.

PubMed

Van Laethem, J L; Gay, F; Franck, N; Van Gossum, A

1992-11-01

Hyperammoniemic encephalopathy has been reported after ureterosigmoidostomy. Its development is related to a problem of bacterial overgrowth and, most often, is favored by the presence of an underlying liver dysfunction. We report the case of a 43-year-old woman with a ureterosigmoidostomy done 28 years earlier who developed hyperammoniemic coma induced by an acute rectocolitis and in the absence of any detectable liver dysfunction. Neither administration of Lactilol and neomycin nor rectal tube drainage were effective; systemic antimicrobial therapy effective against the urease-producing gram-negative bacilli was required and led to a decrease in serum ammonia levels and a dramatic clinical improvement.

Septicemia in a neonatal calf associated with Chromobacterium violaceum.

PubMed

Ajithdoss, D K; Porter, B F; Calise, D V; Libal, M C; Edwards, J F

2009-01-01

Chromobacterium violaceum infections are highly fatal and rarely reported in domestic animals. This report describes a fatal case of C. violaceum septicemia in a 7-day-old female beef calf. The calf had necrosuppurative omphalophlebitis, necrotizing interstitial pneumonia, necrosuppurative hepatitis and splenitis, anterior uveitis with hypopyon, suppurative polyarthritis, and disseminated hemorrhagic meningitis with multifocal necrotizing encephalitis. Histologically, clusters of gram-negative bacilli were found in many of the lesions. C. violaceum was isolated in high numbers from the lungs, liver, spleen, carpus, and in pure culture from the cerebrospinal fluid. To our knowledge, this is the first case report of chromobacteriosis in a calf.

Multifocal suppurative granuloma caused by Actinobacillus lignieresii in the peritoneum of a beef steer

PubMed Central

KASUYA, Kazufumi; MANCHANAYAKE, Tilusha; UENOYAMA, Kei; KAWA, Sayaka; TAKAYAMA, Kou; IMAI, Naoto; SHIBAHARA, Tomoyuki

2016-01-01

An imported crossbred Angus beef steer aged eight to twelve months died suddenly on the eighth day of a quarantine period in Japan. Gross examination showed the peritoneum and mesentery consisted of numerous nodules of various sizes. Histological examination revealed chronic suppurative granulomatous peritonitis with eosinophilic rosettes surrounding colonies of Gram-negative bacilli. The bacteria isolated from the nodules were confirmed to be Actinobacillus lignieresii based on the results of 16S rRNA gene sequencing and immunohistochemistry. Antibiotic sensitivity testing showed that the isolate was resistant to penicillin. Thus, a diagnosis of atypical actinobacillosis caused by A. lignieresii was made. PMID:27773882

Multifocal suppurative granuloma caused by Actinobacillus lignieresii in the peritoneum of a beef steer.

PubMed

Kasuya, Kazufumi; Manchanayake, Tilusha; Uenoyama, Kei; Kawa, Sayaka; Takayama, Kou; Imai, Naoto; Shibahara, Tomoyuki

2017-01-20

An imported crossbred Angus beef steer aged eight to twelve months died suddenly on the eighth day of a quarantine period in Japan. Gross examination showed the peritoneum and mesentery consisted of numerous nodules of various sizes. Histological examination revealed chronic suppurative granulomatous peritonitis with eosinophilic rosettes surrounding colonies of Gram-negative bacilli. The bacteria isolated from the nodules were confirmed to be Actinobacillus lignieresii based on the results of 16S rRNA gene sequencing and immunohistochemistry. Antibiotic sensitivity testing showed that the isolate was resistant to penicillin. Thus, a diagnosis of atypical actinobacillosis caused by A. lignieresii was made.

Moraxella osloensis: an unusual cause of central venous catheter infection in a cancer patient

PubMed Central

Hadano, Yoshiro; Ito, Kenta; Suzuki, Jun; Kawamura, Ichiro; Kurai, Hanako; Ohkusu, Kiyofumi

2012-01-01

Moraxella osloensis is a rare causative organism of infections in humans, with most cases reported in cancer patients. We report the case of a 67-year-old Japanese man with advanced cancer of the pancreatic head and multiple liver metastases who developed fever with chills. Blood culture was found to be positive for Gram-negative bacilli that were aerobic, oxidase-positive, and catalase-positive. M. osloensis was identified by 16 rRNA gene sequencing. Prompt control of the infection was achieved by treatment with cefepime for 14 days, without the need for removal of the central venous catheter. PMID:23109812

Moraxella osloensis: an unusual cause of central venous catheter infection in a cancer patient.

PubMed

Hadano, Yoshiro; Ito, Kenta; Suzuki, Jun; Kawamura, Ichiro; Kurai, Hanako; Ohkusu, Kiyofumi

2012-01-01

Moraxella osloensis is a rare causative organism of infections in humans, with most cases reported in cancer patients. We report the case of a 67-year-old Japanese man with advanced cancer of the pancreatic head and multiple liver metastases who developed fever with chills. Blood culture was found to be positive for Gram-negative bacilli that were aerobic, oxidase-positive, and catalase-positive. M. osloensis was identified by 16 rRNA gene sequencing. Prompt control of the infection was achieved by treatment with cefepime for 14 days, without the need for removal of the central venous catheter.

Microbiology and Epidemiology of Legionnaire's Disease.

PubMed

Burillo, Almudena; Pedro-Botet, María Luisa; Bouza, Emilio

2017-03-01

Legionnaire's disease (LD) is the pneumonic form of legionellosis caused by aerobic gram-negative bacilli of the genus Legionella. Individuals become infected when they inhale aerosolized water droplets contaminated with Legionella species. Forty years after the identification of Legionella pneumophila as the cause of the 1976 pneumonia outbreak in a hotel in Philadelphia, we have non-culture-based diagnostic tests, effective antibiotics, and preventive measures to handle LD. With a mortality rate still around 10%, underreporting, and sporadic outbreaks, there is still much work to be done. In this article, the authors review the microbiology, laboratory diagnosis, and epidemiology of LD. Copyright © 2016 Elsevier Inc. All rights reserved.

Protective efficacy of heat-inactivated B. thailandensis, B. mallei or B. pseudomallei against experimental melioidosis and glanders.

PubMed

Sarkar-Tyson, Mitali; Smither, Sophie J; Harding, S V; Atkins, Timothy P; Titball, Richard W

2009-07-16

Burkholderia pseudomallei and Burkholderia mallei are gram-negative bacilli that are the causative agents of melioidosis and glanders, respectively. Both humans and animals are susceptible to both diseases. There is currently no vaccine available for the prevention of disease. We report the protective efficacy of heat-inactivated Burkholderia thailandensis, B. mallei or B. pseudomallei cells as vaccines against murine melioidosis and glanders. Immunisation with heat-inactivated B. pseudomallei cells provided the highest levels of protection against either melioidosis or glanders. These studies indicate the longer term potential for heat-inactivated bacteria to be developed as vaccines against melioidosis and glanders.

Septic abortion presenting as a right lower trapezius abscess secondary to Bacteroides fragilis bacteraemia.

PubMed

Yamanaka, Yusuke; Shimabukuro, Akira

2017-08-21

A 43-year-old Japanese woman was evaluated in the outpatient department for right shoulder pain and fever, which began 5 days earlier. MRI of the right shoulder revealed a high-intensity area deep in the right trapezius muscle. Aspiration revealed purulent fluid, and Gram staining of the fluid showed Gram-negative bacilli. The patient was also found to be profoundly anaemic and to have a positive urine pregnancy test. On admission, we initiated intravenous ampicillin-sulbactam and aztreonam. She underwent dilatation and curettage for septic abortion and surgical drainage of the right shoulder abscess. Bacteroides fragilis was isolated from the blood, uterine aspiration and abscess samples. On hospital day 4, a whole-body CT scan revealed no other abscesses, and ampicillin-sulbactam was continued for 28 days. The patient was discharged on hospital day 29. Gram staining is an important tool for evaluating infectious aetiologies. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Isolation and speciation of Prevotella strains from periodontal abscesses.

PubMed

Dumitriu, S; Băncescu, G; Murea, A; Skaug, N

1998-01-01

The aims of the study were to isolate and to identify at species level the Prevotella strains in pus samples collected by needle aspiration from 25 Romanian patients with periodontal abscesses. Gram-stained smears and cultures on selective and nonselective media were performed from each of the 25 pus samples. The isolates were identified on the basis of Gram staining, cultural characteristics and standard biochemical reactions. The Gram-negative anaerobic bacilli isolates were biochemically characterized and identified at species level using the Rapid ID 32 A system (Bio Mérieux, France). Fifteen Prevotella isolates belonging to one of the following species: P. melaninogenica, P. denticola, P. oralis, P. loescheii and P. bivia were recovered. All Prevotella isolates reacted similarly in 20 tests in the Rapid ID 32 A system. The P. melaninogenica strain showed approximately the same biochemical profile and only two sugar fermentation tests were not constantly positive. The study confirmed that Prevotella is often involved in periodontal abscesses (> 50% of the cases) in association with other anaerobic or/and aerobic bacteria. P. melaninogenica was the most frequently isolated Prevotella species from the investigated cases.

Soil microbial community responses to acid exposure and neutralization treatment.

PubMed

Shin, Doyun; Lee, Yunho; Park, Jeonghyun; Moon, Hee Sun; Hyun, Sung Pil

2017-12-15

Changes in microbial community induced by acid shock were studied in the context of potential release of acids to the environment due to chemical accidents. The responses of microbial communities in three different soils to the exposure to sulfuric or hydrofluoric acid and to the subsequent neutralization treatment were investigated as functions of acid concentration and exposure time by using 16S-rRNA gene based pyrosequencing and DGGE (Denaturing Gradient Gel Electrophoresis). Measurements of soil pH and dissolved ion concentrations revealed that the added acids were neutralized to different degrees, depending on the mineral composition and soil texture. Hydrofluoric acid was more effectively neutralized by the soils, compared with sulfuric acid at the same normality. Gram-negative ß-Proteobacteria were shown to be the most acid-sensitive bacterial strains, while spore-forming Gram-positive Bacilli were the most acid-tolerant. The results of this study suggest that the Gram-positive to Gram-negative bacterial ratio may serve as an effective bio-indicator in assessing the impact of the acid shock on the microbial community. Neutralization treatments helped recover the ratio closer to their original values. The findings of this study show that microbial community changes as well as geochemical changes such as pH and dissolved ion concentrations need to be considered in estimating the impact of an acid spill, in selecting an optimal remediation strategy, and in deciding when to end remedial actions at the acid spill impacted site. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative Evaluation of Four Phenotypic Tests for Detection of Carbapenemase-Producing Gram-Negative Bacteria

PubMed Central

Noël, Audrey; Berhin, Catherine; Hoebeke, Martin; Bouchahrouf, Warda; Yunus, Sami; Bogaerts, Pierre; Glupczynski, Youri

2016-01-01

ABSTRACT Four screening assays aimed for rapid detection of carbapenemase production from Gram-negative bacterial isolates, i.e., the Neo-Rapid Carb kit (Rosco Diagnostica A/S), the Rapidec Carba NP test (bioMérieux SA), the β Carba test (Bio-Rad Laboratories N.V.), and a homemade electrochemical assay (BYG Carba test) were evaluated against a panel comprising 328 clinical isolates (Enterobacteriaceae [n = 198] and nonfermentative Gram-negative bacilli [n = 130]) with previously characterized resistance mechanisms to carbapenems. Among Enterobacteriaceae isolates, the BYG Carba test and the β Carba test showed excellent sensitivities (respectively, 100% and 97.3%) and specificities (respectively, 98.9% and 97.7%). The two other assays yielded poorer performances with sensitivity and specificity of 91.9% and 83.9% for the Rapidec Carba NP test and of 89.2% and 89.7% for the Neo-Rapid Carb kit, respectively. Among Pseudomonas spp., sensitivities and specificities ranged, respectively, from 87.3% to 92.7% and from 88.2% to 94.1%. Finally, all tests performed poorly against Acinetobacter spp., with sensitivities and specificities, respectively, ranging from 27.3% to 75.8% and from 75 to 100%. Among commercially available assays, the β Carba test appeared to be the most convenient for routine use and showed the best overall performances, especially against OXA-48-like producers. The excellent performance of the BYG Carba test against Enterobacteriaceae was confirmed (100% sensitivity and 98.9% specificity). PMID:27927915

Antimicrobial susceptibility of Gram-negative bacteria causing intra-abdominal infections in China: SMART China 2011.

PubMed

Zhang, Hui; Yang, Qiwen; Xiao, Meng; Chen, Minjun; Badal, Robert E; Xu, Yingchun

2014-01-01

The Study for Monitoring Antimicrobial Resistance Trends program monitors the activity of antibiotics against aerobic and facultative Gram-negative bacilli (GNBs) from intra-abdominal infections (IAIs) in patients worldwide. In 2011, 1 929 aerobic and facultative GNBs from 21 hospitals in 16 cities in China were collected. All isolates were tested using a panel of 12 antimicrobial agents, and susceptibility was determined following the Clinical Laboratory Standards Institute guidelines. Among the Gram-negative pathogens causing IAIs, Escherichia coli (47.3%) was the most commonly isolated, followed by Klebsiella pneumoniae (17.2%), Pseudomonas aeruginosa (10.1%), and Acinetobacter baumannii (8.3%). Enterobacteriaceae comprised 78.8% (1521/1929) of the total isolates. Among the antimicrobial agents tested, ertapenem and imipenem were the most active agents against Enterobacteriaceae, with susceptibility rates of 95.1% and 94.4%, followed by amikacin (93.9%) and piperacillin/tazobactam (87.7%). Susceptibility rates of ceftriaxone, cefotaxime, ceftazidime, and cefepime against Enterobacteriaceae were 38.3%, 38.3%, 61.1%, and 50.8%, respectively. The leastactive agent against Enterobacteriaceae was ampicillin/sulbactam (25.9%). The extended-spectrum β-lactamase (ESBL) rates among E. coli, K. pneumoniae, Klebsiella oxytoca, and Proteus mirabilis were 68.8%, 38.1%, 41.2%, and 57.7%, respectively. Enterobacteriaceae were the major pathogens causing IAIs, and the most active agents against the study isolates (including those producing ESBLs) were ertapenem, imipenem, and amikacin. Including the carbapenems, most agents exhibited reduced susceptibility against ESBL-positive and multidrug-resistant isolates.

Multi-Drug–Resistant Gram-Negative Infections in Deployment-Related Trauma Patients

PubMed Central

Li, Ping; Whitman, Timothy J.; Blyth, Dana M.; Schnaubelt, Elizabeth R.; Mende, Katrin; Tribble, David R.

2017-01-01

Abstract Background: The contribution of multi-drug–resistant gram-negative bacilli infections (MDRGN-I) in patients with trauma is not well described. We present characteristics of MDRGN-Is among military personnel with deployment-related trauma (2009–2014). Patients and Methods: Data from the Trauma Infectious Disease Outcomes Study were assessed for infectious outcomes and microbial recovery. Infections were classified using standardized definitions. Gram-negative bacilli were defined as multi-drug–resistant if they showed resistance to ≥3 antibiotic classes or were producers of extended-spectrum β-lactamase or carbapenemases. Results: Among 2,699 patients admitted to participating U.S. hospitals, 913 (33.8%) experienced ≥1 infection event, of which 245 (26.8%) had a MDRGN-I. There were 543 MDRGN-I events (24.6% of unique 2,210 infections) with Escherichia coli (48.3%), Acinetobacter spp. (38.6%), and Klebsiella pneumoniae (8.4%) as the most common MDRGN isolates. Incidence of MDRGN-I was 9.1% (95% confidence interval [CI]: 8.0–10.2). Median time to MDRGN-I event was seven days with 75% occurring within 13 days post-trauma. Patients with MDRGN-Is had a greater proportion of blast injuries (84.1% vs. 62.5%; p < 0.0001), traumatic amputations (57.5% vs. 16.3%; p < 0.0001), and higher injury severity (82.0% had injury severity score ≥25 vs. 33.7%; p < 0.0001) compared with patients with either no infections or non-MDRGN-Is. Furthermore, MDRGN-I patients were more frequently admitted to the intensive care unit (90.5% vs. 48.5%; p < 0.0001), colonized with a MDRGN before infection (58.0% vs. 14.7%; p < 0.0001), and required mechanical ventilation (78.0% vs. 28.8% p < 0.0001). Antibiotic exposure before the MDRGN-I event was significantly higher across antibiotic classes except first generation cephalosporins and tetracyclines, which were very commonly used with all patients. Regarding outcomes, patients with MDRGN-Is had a longer length of hospitalization than the comparator group (53 vs. 18 days; p < 0.0001). Conclusions: We found a high rate of MDRGN-I in our population characterized by longer hospitalization and greater injury severity. These findings inform treatment and infection control decisions in the trauma patient population. PMID:29173084

Microbiology, infection control and infection related outcome in pediatric patients in an oncology center in Eastern India: Experience from Tata Medical Center, Kolkata.

PubMed

Bhattacharyya, Arpita; Krishnan, Shekhar; Saha, Vaskar; Goel, Gaurav; Bhattacharya, Sanjay; Hmar, Lalawmpuia

2014-01-01

Infection is a major determinant in the outcome of patients with cancer. The aim was to know the epidemiology and outcome of patients with cancer in a cancer care center in Eastern India. Retrospective study of pediatric patients in Tata Medical Center, Kolkata, India. Patients (n = 262) between the age group of 0 and 18 years were reviewed for infections and infection-related outcome (January to December 2013). Modified Wald method was used to determine confidence interval of proportions. Gram-negative bacteria were found to be the most common cause of bloodstream infections (BSIs) (56.4%), followed by Gram-positive cocci (34.5%), and Candida species (9.1%). Carbapenem-resistance was noted among 24% of Gram-negative bacilli (GNB), and extended-spectrum beta-lactamase among 64% of GNBs. A single case of Vibrio cholerae septicemia was also noted. No case of vancomycin-resistant Enterococcus was observed, whereas only two cases of methicillin-resistant Staphylococcus aureus bacteremia (1/3 of all Staphylococcus aureus bacteremia) were detected. Escherichia coli, followed by Klebsiella, Pseudomonas, and Acinetobacter were the predominant organisms detected in BSIs. Among Candida spp. BSIs no resistance to caspofungin, amphotericin B, Voriconazole was noted. Candida tropicalis was the most common isolate, and 1 isolate of Candida glabrata showed dose-dependent sensitivity to fluconazole. Three out of 25 patients died of multi-drug resistant Gram-negative bacteria (12%) in 2013. Seventeen patients had radiological evidence of invasive fungal infections (no mortality was noted). Periodic review of infection-related data, as well as infection control practices, is essential to optimize clinical outcome in patients with pediatric malignancies.

[Analysis of characteristics of bacteria in respiratory tract infection in 2013-2016 in Heibei 3A hospital: a single-center report of 7 497 patients].

PubMed

Hou, Lili; Liu, Lili; Dang, Ping; Kang, Guannan; Zhang, Qinfeng; Li, Dongling

2017-09-01

To analyze the changes and characteristics of respiratory tract bacteria in Hebei 3A Hospital, and to provide new rationale for clinical diagnosis and treatment. A single-center retrospective analysis was conducted. 7 497 patients with respiratory tract infection admitted to Hebei Chest Hospital from January 2013 to December 2016 were enrolled. Deep sputum was collected, and the bacterial cultures and susceptibility analysis was conducted in sputum and upper respiratory secretions were collected by fiberoptic bronchoscopy. A total of 7 497 patients with respiratory tract infection were enrolled in the study, and 11 909 strains of 13 kinds of dominant pathogens were isolated. The dominant pathogens for respiratory tract infection were Monilia albican (23.7%), Klebsiella pneumoniae (12.9%), Pseudomonas aeruginosa (11.6%), Escherichia coli (9.5%), Candida glabrata (9.1%), Acinetobacter baumanii (7.9%), Aspergillus (6.7%), Stenotrophomonas maltophilia (4.5%), coagulase negative Staphylococcus (3.7%) and some species of Pseudomonas (3.7%), Staphylococcus aureus (3.0%), Aerobacter cloacae (1.9%), and Candida tropicalis (1.8%). A total of 6 198 strains of 7 kinds of Gram negative (G - ) bacilli infection dominant pathogens accounts for 52.0% of all infections, Klebsiella pneumonia (24.8%), Pseudomonas aeruginosa (22.3%), Escherichia coli (18.2%) and Acinetobacter baumanii (15.3%) were the main pathogens, and increased year by year. Susceptibility analysis showed that the preferred antibiotics for G - bacteria were carbapenems, followed by risperidone, sulbactam, cefepime, amikacin, and the third generation of cephalosporins. A total of 798 strains of 2 kinds of Gram positive (G + ) bacilli infection dominant pathogens accounted for 6.7% of all infections, were coagulase negative Staphylococcus (54.8%) and Staphylococcus aureus (45.2%), each had changed little by year. Susceptibility analysis showed that G + bacteria were sensitive to glycopeptides, followed by cefoxitin, cotrimoxazole, the tetracyclines, quinolones, azithromycin, erythromycin and so on. The advantages of 4 species of fungi were 4 913 strains, accounted for all of the 41.3% strains, with 57.5% of Candida albicans, and the trend was increasing year by year. Susceptibility analysis results showed that the antifungal susceptibility of dominant fungi were higher. G - bacilli is still the main source of infection, and showed an upward trend year by year. Fungal infection rate cannot be ignored, and we must pay attention to fungal infection incentives. We should strengthen the rational use of antibiotics.

Novel fastidious, partially acid-fast, anaerobic Gram-positive bacillus associated with abscess formation and recovered from multiple medical centers.

PubMed

Harrington, S M; Bell, M; Bernard, K; Lagacé-Wiens, P; Schuetz, A N; Hartman, B; McQuiston, J R; Wilson, D; Lasalvia, M; Ng, B; Richter, S; Taege, A

2013-11-01

We report a novel anaerobe causing abscess in four patients at three hospitals. In the clinical specimen, bacilli were branching, Gram positive, and acid fast. The organism grew slowly and was not identified by 16S rRNA sequencing. Our findings support the description of a new genus and species of the suborder Corynebacterineae.

Molecular analysis, biochemical characterization, antimicrobial activity and immunological analysis of proteus mirabilis isolated from broilers

USDA-ARS?s Scientific Manuscript database

Proteus mirabilis, a peritrichously flagellated Gram-negative bacterium, is ubiquitous in the environment and is the normal microflora in the human gastrointestinal tract. However, this bacterium is an opportunistic pathogen for human, often causing urinary tract infection. Moreover, Proteus has b...

Fecal Microbiota Transfer for Multidrug-Resistant Gram-Negatives: A Clinical Success Combined With Microbiological Failure.

PubMed

Stalenhoef, Janneke E; Terveer, Elisabeth M; Knetsch, Cornelis W; Van't Hof, Peter J; Vlasveld, Imro N; Keller, Josbert J; Visser, Leo G; Kuijper, Eduard J

2017-01-01

Combined fecal microbiota transfer and antibiotic treatment prevented recurrences of urinary tract infections with multidrug-resistant (MDR) Pseudomonas aeruginosa , but it failed to eradicate intestinal colonization with MDR Escherichia coli . Based on microbiota analysis, failure was not associated with distinct diminished microbiota diversity.

Urinary tract infections: a retrospective, descriptive study of causative organisms and antimicrobial pattern of samples received for culture, from a tertiary care setting

PubMed Central

Kalal, Bhuvanesh Sukhlal; Nagaraj, Savitha

2016-01-01

Introduction Urinary tract infections (UTI) are common infections encountered by physicians either on an outpatient or inpatient basis. These infections have taken center stage due to increasing resistance being reported for commonly used antibiotics. Understanding the distribution and antibiotic susceptibility patterns of uropathogens would facilitate appropriate therapy. Methods A retrospective analysis of the culture isolates obtained from urine samples received at the Department of Microbiology, St. John’s Medical College Hospital, Bengaluru India, was performed between January 2012 and May 2012. Results Of the 5592 urine specimens received, 28.2% showed significant growth. A total of 1673 identified pathogens were used in the analysis. Escherichia coli (54.6%) was the most common Gram-negative bacillus, followed by Klebsiella species (9.7%) and Pseudomonas species (7.5%). The most common Gram-positive coccus was Enterococcus (8.8%). Most of the Gram-negative isolates were resistant to ampicillin (79.3%) and cephalosporins (60%). Resistance to cephalosporins and fluoroquinolones was higher in isolates from inpatients. Other than Klebsiella spp., all other Enterobacteriaceae were susceptible to carbapenems (93%) and aminoglycosides (85%), whilst fluoroquinolones were effective for all Gram-positive bacteria. Conclusion Due to a high level of antimicrobial resistance amongst the pathogens causing UTI in India, it is cautious to advise or modify therapy, as far as possible, after culture and sensitivity testing have been performed. Regional surveillance programs are warranted for the development of national UTI guidelines. PMID:28053916

Urinary tract infections: a retrospective, descriptive study of causative organisms and antimicrobial pattern of samples received for culture, from a tertiary care setting.

PubMed

Kalal, Bhuvanesh Sukhlal; Nagaraj, Savitha

2016-12-01

Urinary tract infections (UTI) are common infections encountered by physicians either on an outpatient or inpatient basis. These infections have taken center stage due to increasing resistance being reported for commonly used antibiotics. Understanding the distribution and antibiotic susceptibility patterns of uropathogens would facilitate appropriate therapy. A retrospective analysis of the culture isolates obtained from urine samples received at the Department of Microbiology, St. John's Medical College Hospital, Bengaluru India, was performed between January 2012 and May 2012. Of the 5592 urine specimens received, 28.2% showed significant growth. A total of 1673 identified pathogens were used in the analysis. Escherichia coli (54.6%) was the most common Gram-negative bacillus, followed by Klebsiella species (9.7%) and Pseudomonas species (7.5%). The most common Gram-positive coccus was Enterococcus (8.8%). Most of the Gram-negative isolates were resistant to ampicillin (79.3%) and cephalosporins (60%). Resistance to cephalosporins and fluoroquinolones was higher in isolates from inpatients. Other than Klebsiella spp., all other Enterobacteriaceae were susceptible to carbapenems (93%) and aminoglycosides (85%), whilst fluoroquinolones were effective for all Gram-positive bacteria. Due to a high level of antimicrobial resistance amongst the pathogens causing UTI in India, it is cautious to advise or modify therapy, as far as possible, after culture and sensitivity testing have been performed. Regional surveillance programs are warranted for the development of national UTI guidelines.

Discrimination of selected species of pathogenic bacteria using near-infrared Raman spectroscopy and principal components analysis

NASA Astrophysics Data System (ADS)

de Siqueira e Oliveira, Fernanda SantAna; Giana, Hector Enrique; Silveira, Landulfo

2012-10-01

A method, based on Raman spectroscopy, for identification of different microorganisms involved in bacterial urinary tract infections has been proposed. Spectra were collected from different bacterial colonies (Gram-negative: Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa and Enterobacter cloacae, and Gram-positive: Staphylococcus aureus and Enterococcus spp.), grown on culture medium (agar), using a Raman spectrometer with a fiber Raman probe (830 nm). Colonies were scraped from the agar surface and placed on an aluminum foil for Raman measurements. After preprocessing, spectra were submitted to a principal component analysis and Mahalanobis distance (PCA/MD) discrimination algorithm. We found that the mean Raman spectra of different bacterial species show similar bands, and S. aureus was well characterized by strong bands related to carotenoids. PCA/MD could discriminate Gram-positive bacteria with sensitivity and specificity of 100% and Gram-negative bacteria with sensitivity ranging from 58 to 88% and specificity ranging from 87% to 99%.

Childhood pyogenic meningitis: clinical and investigative indicators of etiology and outcome.

PubMed Central

Johnson, Abdul-Wahab B. R.; Adedoyin, Olanrewaju T.; Abdul-Karim, Aishat A.; Olanrewaju, Abdul-Waheed I.

2007-01-01

The relevant parameters of 71 consecutive pediatric admissions for pyogenic meningitis at the University of Ilorin Teaching Hospital, Ilorin, Nigeria, were analyzed to identify possible clinical and nonmicrobiologic investigative clues of disease etiology and mortality. Cerebrospinal fluid (CSF) was Gram-smear positive (GSP) in 41 (57.6%) of the 71 cases. Twenty-three (56.1%) had Gram-positive cocci (GPC), 14 (34.2%) Gram-negative bacilli (GNB) and three (7.3%) Gram-negative diplococci (GND). The respective mean ages of GPC, GNB and GND cases were 4.49 +/- 5.3, 3.06 +/- 4.8 and 4.47 +/-4.9 years. Streptococcus pneumoniae accounted for 22 (78.6%) of the 28 CSF isolates (p=0.00), Haemophilus influenzae for two (7.1%) cases and Neisseria meningitides in one (3.5%). Anemia was significantly more common among GSP cases (p=0.04), as was convulsion among those with GNB-positive smears (p=0.03) and a bulging fontanelle in the Gram-smear-negative category. Otherwise, the prevalence and resolution times of the other clinical parameters were comparable across the etiological categories. There were 30 deaths (42.3%) among which GNB-positive cases had significantly shorter stay (p=0.045). Mortality was significantly higher in those with an abnormal respiratory rhythm at admission (p=0.04), purulent/turbid CSF (p=0.03), CSF protein of >150 mg/dl (p=0.02) and glucose <1 mg/dl (p=0.047). Our findings highlight the inherent limitations of predicting the etiology of pediatric meningitides from the clinical parameters as well as the poor prognostic import of respiratory dysrhythmia and a profoundly deranged CSF protein and glucose. The etiological burden of GPC/S. pneumoniae in childhood meningitides in sub-Saharan Africa, the propensity of GNB/H. influenzae for quick fatality and the need for the relevant preventive vaccines are expounded in the discussion. PMID:17722674

Prevotella maculosa sp. nov., isolated from the human oral cavity.

PubMed

Downes, Julia; Sutcliffe, Iain C; Booth, Veronica; Wade, William G

2007-12-01

Three strains of anaerobic Gram-negative bacilli isolated from human oral sites were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis revealed the strains to constitute a novel group within the genus Prevotella, most closely related to Prevotella oris and Prevotella salivae. A novel species, Prevotella maculosa sp. nov., is proposed to accommodate these strains. Prevotella maculosa is saccharolytic and produces acetic and succinic acids as end products of fermentation. The G+C content of the DNA of the type strain is 48 mol%. The type strain of Prevotella maculosa is W1609(T) (=DSM 19339(T) =CCUG 54766(T)).

Infections in cancer patients on a protected environment-prophylactic antibiotic program.

PubMed

Bodey, G P; Rodriguez, V

1975-10-01

A total of 102 studies were conducted on 89 patients receiving cancer chemotherapy while on a protected environment-prophylactic antibiotic program. Major infections occurred during 22 studies. The majority of both minor and major infections originated during the first five weeks after the patients entered the protected environment units. The frequency of infectious complications was inversely related to the circulating neutrophil count. The majority of infections were cases of cellulitis, pharyngitis, pneumonia and septicemia. Most of the infections were caused by gram-negative bacilli. The majority of organisms causing infection had persisted in the patients after their entry into the protected environment units despite the use of prophylactic antibiotics.

Hand sanitizer dispensers and associated hospital-acquired infections: friend or fomite?

PubMed

Eiref, Simon D; Leitman, I Michael; Riley, William

2012-06-01

Waterless alcohol-based hand sanitizers are an increasingly popular method of hand hygiene and help prevent hospital-acquired infection (HAI). Whether hand sanitizer dispensers (HSDs) may themselves harbor pathogens or act as fomites has not been reported. All HSDs in the surgical intensive care unit of an urban teaching hospital were cultured at three sites: The dispenser lever, the rear underside, and the area surrounding the dispensing nozzle. All HSDs yielded one or more bacterial species, including commensal skin flora and enteric gram-negative bacilli. Colonization was greatest on the lever, where there is direct hand contact. Hand sanitizer dispensers can become contaminated with pathogens that cause HAI and thus are potential fomites.

β-Lactamase Production in Key Gram-Negative Pathogen Isolates from the Arabian Peninsula

PubMed Central

Balkhy, Hanan H.; Walsh, Timothy R.; Paterson, David L.

2013-01-01

SUMMARY Infections due to Gram-negative bacilli (GNB) are a leading cause of morbidity and mortality worldwide. The extent of antibiotic resistance in GNB in countries of the Gulf Cooperation Council (GCC), namely, Saudi Arabia, United Arab Emirates, Kuwait, Qatar, Oman, and Bahrain, has not been previously reviewed. These countries share a high prevalence of extended-spectrum-β-lactamase (ESBL)- and carbapenemase-producing GNB, most of which are associated with nosocomial infections. Well-known and widespread β-lactamases genes (such as those for CTX-M-15, OXA-48, and NDM-1) have found their way into isolates from the GCC states. However, less common and unique enzymes have also been identified. These include PER-7, GES-11, and PME-1. Several potential risk factors unique to the GCC states may have contributed to the emergence and spread of β-lactamases, including the unnecessary use of antibiotics and the large population of migrant workers, particularly from the Indian subcontinent. It is clear that active surveillance of antimicrobial resistance in the GCC states is urgently needed to address regional interventions that can contain the antimicrobial resistance issue. PMID:23824364

[Study of bacterial flora in the oral cavity and stomach of elderly patients receiving nasogastric tube feeding].

PubMed

Matsuura, T; Suzuki, K; Yamakoshi, M; Yamamoto, T; Yamamoto, T; Yoshitomo, K; Tonegawa, K; Ariga, K; Odawara, F

1997-05-01

To investigate the significance of oropharyngeal flora and gastric flora in elderly patients receiving nasogastric tube feeding, throat secretions and gastric aspirates were cultured and the pH of the latter was measured. Of 116 bacterial isolates from throat secretions of 27 elderly patients, 30 were beta-streptococci and 28 were Pseudomonas aeruginosa. Bacteria isolated from gastric aspirates numbered 86 and 24 (27.9%) of them were the same species as those found in the throat secretions. Patients with gastric pH were below 3.5 had significantly lower concentrations of gram-negative bacili in gastric aspirates. We also studied oropharyngeal flora in 33 elderly patients who were admitted to Nagoyashi Koseiin Geriatric Hospital. The major bacterial isolates from throat swabs of bedridden patients were gram-negative bacilli and beta-streptococci, especially group B streptococci (GBS). We measured the level of antibody to GBS in these patients. Those from whom GBS were isolated had high titers. These results suggest that in elderly patients receiving enteral nasogastric) tube feeding, large numbers of bacteria colonize the oral cavity and stomach. The measurement of type-specific antibody to GBS may be useful in managing such patients.

Effectiveness of oral antibiotics for definitive therapy of Gram-negative bloodstream infections.

PubMed

Kutob, Leila F; Justo, Julie Ann; Bookstaver, P Brandon; Kohn, Joseph; Albrecht, Helmut; Al-Hasan, Majdi N

2016-11-01

There is paucity of data evaluating intravenous-to-oral antibiotic switch options for Gram-negative bloodstream infections (BSIs). This retrospective cohort study examined the effectiveness of oral antibiotics for definitive treatment of Gram-negative BSI. Patients with Gram-negative BSI hospitalised for <14 days at Palmetto Health Hospitals in Columbia, SC, from 1 January 2010 through 31 December 2013 and discharged on oral antibiotics were included in this study. The cohort was stratified into three groups based on bioavailability of oral antibiotics prescribed (high, ≥95%; moderate, 75-94%; and low, <75%). Kaplan-Meier analysis and multivariate Cox proportional hazards regression were used to examine treatment failure. Among the 362 patients, high, moderate and low bioavailability oral antibiotics were prescribed to 106, 179 and 77 patients, respectively, for definitive therapy of Gram-negative BSI. Mean patient age was 63 years, 217 (59.9%) were women and 254 (70.2%) had a urinary source of infection. Treatment failure rates were 2%, 12% and 14% in patients receiving oral antibiotics with high, moderate and low bioavailability, respectively (P = 0.02). Risk of treatment failure in the multivariate Cox model was higher in patients receiving antibiotics with moderate [adjusted hazard ratio (aHR) = 5.9, 95% CI 1.6-38.5; P = 0.005] and low bioavailability (aHR = 7.7, 95% CI 1.9-51.5; P = 0.003) compared with those receiving oral antimicrobial agents with high bioavailability. These data demonstrate the effectiveness of oral antibiotics with high bioavailability for definitive therapy of Gram-negative BSI. Risk of treatment failure increases as bioavailability of the oral regimen declines. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Monolateral suppurative parotitis in a neonate and review of literature.

PubMed

Decembrino, Lidia; Ruffinazzi, Giulia; Russo, Fabio; Manzoni, Paolo; Stronati, Mauro

2012-07-01

Neonatal suppurative parotitis is a rare condition characterized by swelling, pain, and erythema over the affected gland. Antimicrobials and adequate hydration are an essential part of treatment. Surgical intervention is reserved for organized abscesses and for infections not responding to medical management. A case report and review of the literature. Only few case reports and case series are reported in literature on neonatal parotitis. Transmission of bacteria seems to occur mainly by ascending spread through Stensen's duct, or by hematogenous spread from a distant focus. Dehydration, low birth weight, immune suppression, ductal obstruction, oral trauma and structural abnormalities of the parotid gland are recognised as risk factors. The most common pathogen is Staphylococcus aureus. Other less frequent agents are other Gram-positive cocci, Gram-negative bacilli and rarely anaerobic bacteria. Advances in antimicrobial therapy have improved both outcome and prognosis. Thanks to the prompt antibiotic treatment complications are now drastically reduced. Ultrasound examination may help in the diagnosis and monitoring of clinical course. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

[Prevotella species involved in the onset of superficial face and neck abscesses].

PubMed

Băncescu, Gabriela; Dumitriu, Silvia; Băncescu, A; Preoteasa, Elena; Skaug, N

2004-01-01

The aim of the study was to identify at species level the Prevotella strains from 30 pus samples collected by needle aspiration in patients with abscesses of fascial spaces of the face and neck. Microscopy of Gram-stained direct smear and cultures on selective and nonselective media incubated aerobically and anaerobically were performed in each pus specimen. All strains of Gram-negative strictly anaerobic bacilli were identified to genus and species level using conventional methods of diagnosis and the Rapid ID 32 A system (BioMérieux, Marcy-l'Etoile, France). The Prevotella isolates were recovered (alone or in association with other bacteria) in 46.6% of the investigated specimens and were represented in reverse order of frequency by the following species: P. melaninogenica, P. denticola, P. oralis and P. loescheii. In conclusion, the rate of Prevotella isolation was relatively high and the most frequently isolated species was P. melaninogenica (followed by P. denticola), while no P. intermedia was found.

Detection of biological threats. A challenge for directed molecular evolution.

PubMed

Petrenko, Valery A; Sorokulova, Iryna B

2004-08-01

The probe technique originated from early attempts of Anton van Leeuwenhoek to contrast microorganisms under the microscope using plant juices, successful staining of tubercle bacilli with synthetic dyes by Paul Ehrlich and discovery of a stain for differentiation of gram-positive and gram-negative bacteria by Hans Christian Gram. The technique relies on the principle that pathogens have unique structural features, which can be recognized by specifically labeled organic molecules. A hundred years of extensive screening efforts led to discovery of a limited assortment of organic probes that are used for identification and differentiation of bacteria. A new challenge--continuous monitoring of biological threats--requires long lasting molecular probes capable of tight specific binding of pathogens in unfavorable conditions. To respond to the challenge, probe technology is being revolutionized by utilizing methods of combinatorial chemistry, phage display and directed molecular evolution. This review describes how molecular evolution methods are applied for development of peptide, antibody and phage probes, and summarizes the author's own data on development of landscape phage probes against Salmonella typhimurium. The performance of the probes in detection of Salmonella is illustrated by a precipitation test, enzyme-linked immunosorbent assay (ELISA), fluorescence-activated cell sorting (FACS) and fluorescent, optical and electron microscopy.

Epidemiology and trends in the antibiotic susceptibilities of Gram-negative bacilli isolated from patients with intra-abdominal infections in the Asia-Pacific region, 2010-2013.

PubMed

Chang, Ya-Ting; Coombs, Geoffrey; Ling, Thomas; Balaji, V; Rodrigues, Camilla; Mikamo, Hiroshige; Kim, Min-Ja; Rajasekaram, Datin Ganeswrie; Mendoza, Myrna; Tan, Thean Yen; Kiratisin, Pattarachai; Ni, Yuxing; Barry, Weinman; Xu, Yingchun; Chen, Yen-Hsu; Hsueh, Po-Ren

2017-06-01

This study was conducted to investigate the epidemiology and antimicrobial susceptibility patterns of Gram-negative bacilli (GNB) isolated from intra-abdominal infections (IAIs) in the Asia-Pacific region (APR) from 2010-2013. A total of 17 350 isolates were collected from 54 centres in 13 countries in the APR. The three most commonly isolated GNB were Escherichia coli (46.1%), Klebsiella pneumoniae (19.3%) and Pseudomonas aeruginosa (9.8%). Overall, the rates of extended-spectrum β-lactamase (ESBL)-producing E. coli and K. pneumoniae were 38.2% and 24.3%, respectively, and they were highest in China (66.6% and 38.7%, respectively), Thailand (49.8% and 36.5%, respectively) and Vietnam (47.9% and 30.4%, respectively). During 2010-2013, the rates of ESBL-producing E. coli and K. pneumoniae isolates causing community-associated (CA) IAIs (collected <48 h after admission) were 26.0% and 13.5%, respectively, and those causing hospital-associated (HA) IAIs were 48.0% and 30.6%, respectively. Amikacin, ertapenem and imipenem were the most effective agents against ESBL-producing isolates. Piperacillin/tazobactam displayed good in vitro activity (91.4%) against CA ESBL-producing E. coli. For other commonly isolated Enterobacteriaceae, fluoroquinolones, cefepime and carbapenems exhibited better in vitro activities than third-generation cephalosporins. Amikacin possessed high in vitro activity against all GNB isolates (>80%) causing IAIs, except for Acinetobacter calcoaceticus-baumannii (ACB) complex (30.9% for HA-IAI isolates). All of the antimicrobial agents tested exhibited <45% in vitro activity against ACB complex. Antimicrobial resistance is a persistent threat in the APR and continuous monitoring of evolutionary trends in the susceptibility patterns of GNB causing IAIs in this region is mandatory. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Multidrug and co-resistance patterns of non-fermenting Gram-negative bacilli involved in ventilator-associated pneumonia carrying class 1 integron in the North of Iran.

PubMed

Bagheri-Nesami, Masoumeh; Rezai, Mohammad Sadegh; Ahangarkani, Fatemeh; Rafiei, Alireza; Nikkhah, Attieh; Eslami, Gohar; Shafahi, Kheironesa; Hajalibeig, Azin; Khajavi, Rezvan

2017-09-01

Ventilator-associated pneumonia (VAP) due to non-fermenting Gram-negative bacilli (NFGNB), especially Pseudomonas aeruginosa and Acinetobacter spp., is one of the main hospital-acquired infections leading to mortality and morbidity, especially in intensive care units (ICUs). This study seeks to determine the multidrug and co-resistance (MDR) patterns of NFGNB that are agents of VAP, and assess the presence of class 1 integron in these bacteria. This cross-sectional study involved VAP patients admitted in the ICUs of 18 hospitals in the Mazandaran province, located in the North of Iran. The antibiotic susceptibility pattern was determined by the minimum inhibitory concentration (MIC) test by using broth microdilution method. Presence of class 1 integron was evaluated by the polymerase chain reaction (PCR) assay. Out of a total of 83 patients who were microbiologically diagnosed as VAP, 52 non-duplicated NFGNBs (24 P. aeruginosa and 28 A. baumannii ) were causative of VAP, out of which MDR NFGNBs were responsible for 48 (57.83%) cases. The frequencies of MDR NFGNBs were as follows: 27 (56.25%) A. baumannii and 21 (43.75%) P. aeruginosa . P. aeruginosa isolates were resistant to all aminoglycoside antibiotics (50%), ciprofloxacin (45.8%), ceftazidime (70.8%), cefepime (87.5%), colistin (62.5%), and imipenem (29.2%). A. baumannii isolates were resistant to aminoglycosides (53.6%), ciprofloxacin (85.7%), ceftazidime (92. 9%), cefepime (92.9%), colistin (35.7%), and imipenem (57.1%). Twelve isolates were resistant to all 10 tested antibiotics. The number of rates of class 1 integron, positive for MDR P. aeruginosa and MDR A. baumannii , were 20 (95.23%) and 21 (77.78%), respectively. The high prevalence of multidrug resistance and incidence of class 1 integron is a therapeutic concern. Employing antibiotic stewardship in hospitals could prevent the dissemination of MDR bacteria.

Clinical pulmonary infection score and a spot serum procalcitonin level to guide discontinuation of antibiotics in ventilator-associated pneumonia: a study in a single institution with high prevalence of nonfermentative gram-negative bacilli infection.

PubMed

Wongsurakiat, Phunsup; Tulatamakit, Sirapat

2018-01-01

Background We wanted to determine the impact of combined Clinical Pulmonary Infection Score (CPIS) and a spot serum procalcitonin (PCT)-guided protocol to shorten the duration of antibiotic treatment in patients with ventilator-associated pneumonia (VAP), mainly caused by nonfermentative gram-negative bacilli (NF-GNB). Methods Patients with VAP who received appropriate antibiotics for 7 days, temperature ⩽ 37.8°C, without shock, and CPIS ⩽ 6 were allocated to the PCT group or conventional group according to the treating physicians' decisions. In the PCT group, antibiotics were stopped if the PCT level on day 8 < 0.5 ng/ml. In the conventional group, antibiotics were stopped according to physicians' discretion. Results There were 24 patients in the PCT group and 26 patients in the conventional group. NF-GNB were responsible for VAP in 79.2% of the PCT group and 65.4% of the conventional group. PCT group had a greater number of antibiotic-free days alive during the 28 days after VAP onset than the conventional group (14.6 ± 5.4 days versus 5.9 ± 5.7 days, respectively; p <.001). In the multivariate, propensity score-adjusted analysis, the PCT group [coefficient = -9.1 (-12.2 to -6); p <.001] and extrapulmonary infections [coefficient = 6.4 (3.3-9.5); p <.001] were independent predictors of total antibiotic exposure days. There was no relapse in both groups. Meanwhile, 12.5% of the PCT group and 26.9% of the conventional group subsequently developed recurrent VAP compatible with superinfections. Conclusions CPIS and a spot serum PCT level appeared effective and safe to guide discontinuation of antibiotic treatment in patients with VAP caused by NF-GNB. TCTR20160726002.

Outcome of Acute Prosthetic Joint Infections Due to Gram-Negative Bacilli Treated with Open Debridement and Retention of the Prosthesis▿

PubMed Central

Martínez-Pastor, Juan C.; Muñoz-Mahamud, Ernesto; Vilchez, Félix; García-Ramiro, Sebastián; Bori, Guillem; Sierra, Josep; Martínez, José A.; Font, Lluis; Mensa, Josep; Soriano, Alex

2009-01-01

The aim of our study was to evaluate the outcome of acute prosthetic joint infections (PJIs) due to gram-negative bacilli (GNB) treated without implant removal. Patients with an acute PJI due to GNB diagnosed from 2000 to 2007 were prospectively registered. Demographics, comorbidity, type of implant, microbiology data, surgical treatment, antimicrobial therapy, and outcome were recorded. Classification and regression tree analysis, the Kaplan-Meier survival method, and the Cox regression model were applied. Forty-seven patients were included. The mean age was 70.7 years, and there were 15 hip prostheses and 32 knee prostheses. The median number of days from the time of arthroplasty was 20. The most frequent pathogens were members of the Enterobacteriaceae family in 41 cases and Pseudomonas spp. in 20 cases. Among the Enterobacteriaceae, 14 were resistant to ciprofloxacin, while all Pseudomonas aeruginosa isolates were susceptible to ciprofloxacin. The median durations of intravenous and oral antibiotic treatment were 14 and 64 days, respectively. A total of 35 (74.5%) patients were in remission after a median follow-up of 463 days (interquartile range, 344 to 704) days. By use of the Kaplan-Meier survival curve, a C-reactive protein (CRP) concentration of ≤15 mg/dl (P = 0.03) and receipt of a fluoroquinolone, when all GNB isolated were susceptible (P = 0.0009), were associated with a better outcome. By use of a Cox regression model, a CRP concentration of ≤15 mg/dl (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.05 to 12.5; P = 0.043) and receipt of a fluoroquinolone (OR, 9.09; 95% CI, 1.96 to 50; P = 0.005) were independently associated with better outcomes. Open debridement without removal of the implant had a success rate of 74.5%, and the factors associated with good prognosis were a CRP concentration at the time of diagnosis ≤15 mg/dl and treatment with a fluoroquinolone. PMID:19687237

The Increasing Challenge of Multidrug-Resistant Gram-Negative Bacilli

PubMed Central

Giuffrè, Mario; Geraci, Daniela M.; Bonura, Celestino; Saporito, Laura; Graziano, Giorgio; Insinga, Vincenzo; Aleo, Aurora; Vecchio, Davide; Mammina, Caterina

2016-01-01

Abstract Colonization and infection by multidrug-resistant gram-negative bacilli (MDR GNB) in neonatal intensive care units (NICUs) are increasingly reported. We conducted a 5-year prospective cohort surveillance study in a tertiary NICU of the hospital “Paolo Giaccone,” Palermo, Italy. Our objectives were to describe incidence and trends of MDR GNB colonization and the characteristics of the most prevalent organisms and to identify the risk factors for colonization. Demographic, clinical, and microbiological data were prospectively collected. Active surveillance cultures (ASCs) were obtained weekly. Clusters of colonization by extended spectrum β-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae were analyzed by conventional and molecular epidemiological tools. During the study period, 1152 infants were enrolled in the study. Prevalences of colonization by MDR GNB, ESBL-producing GNB and multiple species/genera averaged, respectively, 28.8%, 11.7%, and 3.7%. Prevalence and incidence density of colonization by MDR GNB and ESBL-producing GNB showed an upward trend through the surveillance period. Rates of ESBL-producing E coli and K pneumoniae colonization showed wide fluctuations peaking over the last 2 years. The only independent variables associated with colonization by MDR GNB and ESBL-producing organisms and multiple colonization were, respectively, the days of NICU stay (odds ratio [OR] 1.041), the days of exposure to ampicillin–sulbactam (OR 1.040), and the days of formula feeding (OR 1.031). Most clusters of E coli and K pneumoniae colonization were associated with different lineages. Ten out of 12 clusters had an outborn infant as their index case. Our study confirms that MDR GNB are an increasing challenge to NICUs. The universal once-a-week approach allowed us to understand the epidemiology of MDR GNB, to timely detect new clones and institute contact precautions, and to assess risk factors. Collection of these data can be an important tool to optimize antimicrobials use and control the emergence and dissemination of resistances in NICU. PMID:26962817

Outcome of acute prosthetic joint infections due to gram-negative bacilli treated with open debridement and retention of the prosthesis.

PubMed

Martínez-Pastor, Juan C; Muñoz-Mahamud, Ernesto; Vilchez, Félix; García-Ramiro, Sebastián; Bori, Guillem; Sierra, Josep; Martínez, José A; Font, Lluis; Mensa, Josep; Soriano, Alex

2009-11-01

The aim of our study was to evaluate the outcome of acute prosthetic joint infections (PJIs) due to gram-negative bacilli (GNB) treated without implant removal. Patients with an acute PJI due to GNB diagnosed from 2000 to 2007 were prospectively registered. Demographics, comorbidity, type of implant, microbiology data, surgical treatment, antimicrobial therapy, and outcome were recorded. Classification and regression tree analysis, the Kaplan-Meier survival method, and the Cox regression model were applied. Forty-seven patients were included. The mean age was 70.7 years, and there were 15 hip prostheses and 32 knee prostheses. The median number of days from the time of arthroplasty was 20. The most frequent pathogens were members of the Enterobacteriaceae family in 41 cases and Pseudomonas spp. in 20 cases. Among the Enterobacteriaceae, 14 were resistant to ciprofloxacin, while all Pseudomonas aeruginosa isolates were susceptible to ciprofloxacin. The median durations of intravenous and oral antibiotic treatment were 14 and 64 days, respectively. A total of 35 (74.5%) patients were in remission after a median follow-up of 463 days (interquartile range, 344 to 704) days. By use of the Kaplan-Meier survival curve, a C-reactive protein (CRP) concentration of < or = 15 mg/dl (P = 0.03) and receipt of a fluoroquinolone, when all GNB isolated were susceptible (P = 0.0009), were associated with a better outcome. By use of a Cox regression model, a CRP concentration of < or = 15 mg/dl (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.05 to 12.5; P = 0.043) and receipt of a fluoroquinolone (OR, 9.09; 95% CI, 1.96 to 50; P = 0.005) were independently associated with better outcomes. Open debridement without removal of the implant had a success rate of 74.5%, and the factors associated with good prognosis were a CRP concentration at the time of diagnosis < or = 15 mg/dl and treatment with a fluoroquinolone.

Surveillance of antimicrobial susceptibility of aerobic and facultative Gram-negative bacilli isolated from patients with intra-abdominal infections in China: the 2002-2009 Study for Monitoring Antimicrobial Resistance Trends (SMART).

PubMed

Yang, Qiwen; Wang, Hui; Chen, Minjun; Ni, Yuxing; Yu, Yunsong; Hu, Bijie; Sun, Ziyong; Huang, Wenxiang; Hu, Yunjian; Ye, Huifen; Badal, Robert E; Xu, Yingchun

2010-12-01

The objective of this study was to investigate the distribution and susceptibility of aerobic and facultative Gram-negative bacilli (GNB) isolated from patients with intra-abdominal infections (IAIs) in China. From 2002 to 2009, minimum inhibitory concentrations of 14 antibiotics for 3420 aerobic and facultative GNB from up to eight hospitals in six cities were determined by the broth microdilution method. Enterobacteriaceae comprised 82.9% (2834/3420) of the total isolates, with Escherichia coli (49.2%) being the most commonly isolated species followed by Klebsiella pneumoniae (17.0%), Enterobacter cloacae (5.8%) and Citrobacter freundii (2.3%). Amongst the antimicrobial agents tested, the three carbapenems (ertapenem, imipenem and meropenem) were the most active agents against Enterobacteriaceae, with susceptibility rates of 96.1-99.6% (2002-2009), 98.2-100% (2002-2009) and 99.6-100% (2002-2004), respectively, followed by amikacin (86.8-95.1%) and piperacillin/tazobactam (84.5-94.3%). Susceptibility rates of all tested third- and fourth-generation cephalosporins against Enterobacteriaceae declined by nearly 30%, with susceptibility rates of 40.2%, 39.1%, 56.3% and 51.8% in 2009 for ceftriaxone, cefotaxime, ceftazidime and cefepime, respectively. The occurrence of extended-spectrum β-lactamases increased rapidly, especially for E. coli (from 20.8% in 2002 to 64.9% in 2009). Susceptibility of E. coli to ciprofloxacin decreased from 57.6% in 2002 to 24.2% in 2009. The least active agent against Enterobacteriaceae was ampicillin/sulbactam (SAM) (25.3-44.3%). In conclusion, Enterobacteriaceae were the major pathogens causing IAIs, and carbapenems retained the highest susceptibility rates over the 8-year study period. Third- and fourth-generation cephalosporins, fluoroquinolones and SAM may not be ideal choices for empirical therapy of IAIs in China. Copyright © 2010 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Impact of imipenem and amikacin pharmacokinetic/pharmacodynamic parameters on microbiological outcome of Gram-negative bacilli ventilator-associated pneumonia.

PubMed

Pajot, O; Burdet, C; Couffignal, C; Massias, L; Armand-Lefevre, L; Foucrier, A; Da Silva, D; Lasocki, S; Laouénan, C; Mentec, H; Mentré, F; Wolff, M

2015-05-01

Despite recent advances, antibiotic therapy of ventilator-associated pneumonia (VAP) in ICU patients is still challenging. We assessed the impact of imipenem and amikacin pharmacokinetic and pharmacodynamic parameters on microbiological outcome in these patients. Patients with Gram-negative bacilli (GNB) VAP were prospectively included. Blood samples for pharmacokinetic analysis were collected after empirical administration of a combination of imipenem three times daily and one single dose of amikacin. MICs were estimated for each GNB obtained from respiratory samples. Microbiological success was defined as a ≥10(3) cfu/mL decrease in bacterial count in quantitative cultures between baseline and the third day of treatment. Thirty-nine patients [median (min-max) age = 60 years (28-84) and median SAPS2 at inclusion = 40 (19-73)] were included. Median MICs of imipenem and amikacin were 0.25 mg/L (0.094-16) and 2 mg/L (1-32), respectively. Median times over MIC and over 5× MIC for imipenem were 100% (8-100) and 74% (3-100), respectively. The median C1/MIC ratio for amikacin was 23 (1-76); 34 patients (87%) achieved a C1/MIC ≥10. Microbiological success occurred in 29 patients (74%). No imipenem pharmacodynamic parameter was significantly associated with the microbiological success. For amikacin, C1/MIC was significantly higher in the microbiological success group: 26 (1-76) versus 11 (3-26) (P = 0.004). In ICU patients with VAP, classic imipenem pharmacodynamic targets are easily reached with usual dosing regimens. In this context, for amikacin, a higher C1/MIC ratio than previously described might be necessary. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Distribution and Antimicrobial Susceptibility Pattern of Bacterial Pathogens Causing Urinary Tract Infection in Urban Community of Meerut City, India

PubMed Central

Prakash, Devanand; Saxena, Ramchandra Sahai

2013-01-01

Urinary tract infection is one of the common infections in the Indian community. Distribution and susceptibility of UTI-causing pathogens change according to time and place. This study was conducted to determine the distribution and antimicrobial susceptibility of uropathogens in the Indian community as well as to determine the effect of gender and age on the etiology of bacterial uropathogens. Clean catch midstream urine samples were collected from 288 patients of the age ranging from 15 to ≥48 years. Antimicrobial susceptibility was performed on all isolated bacteria by Kirby Bauer's disc diffusion method. The multiple antibiotic resistance (MAR) index of each antibiotic was calculated. The UTI prevalence was 53.82% in patients; however, the prevalence was significantly higher in females than in males (females: 73.57%; males: 35.14%; P = 0.000). Females within the age group of 26–36 years and elderly males of ≥48 years showed higher prevalence of UTI. Gram negative bacteria (90.32%) were found in high prevalence than Gram positive (9.68%). Escherichia coli (42.58%) was the most prevalent gram negative isolate. Nitrofurantoin (78.71%) was found the most resistant drug among all uropathogens. Tested carbapenems were found the most susceptible drug against isolated uropathogens which showed 92.26% and 84.52% susceptibility, respectively. PMID:24288649

Cerebral hemorrhage in infective endocarditis caused by Actinobacillus actinomycetemcomitans.

PubMed

Lin, Gen-Min; Chu, Kai-Min; Juan, Chun-Jung; Chang, Feng-Yee

2007-11-01

Cerebral hemorrhage occurs rarely in endocarditis caused by Actinobacillus actinomycetemcomitans. A 51-year-old man with a prosthetic mitral valve, who had been prophylactically treated (7 years) with warfarin, presented with intermittent fever. On admission, a Levine grade II/VI systolic cardiac murmur was detected. A transthoracic echocardiogram was negative for valve vegetation. Cefepime (1 g every 8 hours) was administered intravenously. On day 4, culturing of Gram-negative bacilli from blood and a transesophageal echocardiogram revealed a small oscillating filament attached to lateral mitral prosthetic ring on the atrial side. Ceftriaxone (2 g once daily) was started. Gait instability and left-side weakness developed abruptly 2 weeks later; brain magnetic resonance imaging revealed a hematoma over the right parietal-occipital lobe. Ceftriaxone was adjusted to 2 g every 12 hours. Actinobacillus actinomycetemcomitans was identified 3 weeks later. Recovery was achieved, with significant interval improvement and resolution of the cerebral lesions evident on CT.

Antibiotic prescribing at the transition from hospitalization to discharge: a target for antibiotic stewardship

PubMed Central

Yogo, Norihiro; Haas, Michelle K; Knepper, Bryan C; Burman, William J; Mehler, Philip S; Jenkins, Timothy C

2016-01-01

Of 300 patients prescribed oral antibiotics at the time of hospital discharge, urinary tract infection, community-acquired pneumonia , and skin infections accounted for 181 (60%) of the treatment indications. Half of the prescriptions were antibiotics with broad gram-negative activity. Discharge prescriptions were inappropriate in 79 (53%) of 150 cases reviewed. PMID:25782905

Population Pharmacokinetic Analysis of Cefiderocol, a Parenteral Siderophore Cephalosporin, in Healthy Subjects, Subjects with Various Degrees of Renal Function, and Patients with Complicated Urinary Tract Infection or Acute Uncomplicated Pyelonephritis

PubMed Central

Kawaguchi, Nao; Echols, Roger; Wajima, Toshihiro

2018-01-01

ABSTRACT Cefiderocol, a novel parenteral siderophore cephalosporin, exhibits potent efficacy against most Gram-negative bacteria, including carbapenem-resistant strains. The aim of this study was to perform a population pharmacokinetic (PK) analysis based on plasma cefiderocol concentrations in healthy subjects, subjects with various degrees of renal function, and patients with complicated urinary tract infection (cUTI) or acute uncomplicated pyelonephritis (AUP) caused by Gram-negative pathogens and to calculate the fraction of the time during the dosing interval where the free drug concentration in plasma exceeds the MIC (fTMIC). Population PK models were developed with three renal function markers, body surface area-adjusted estimated glomerular filtration rate (eGFR), absolute eGFR, and creatinine clearance, on the basis of 2,571 plasma concentrations from 91 subjects without infection and 238 patients with infection. The population PK models with each renal function marker adequately described the plasma cefiderocol concentrations. Clear relationships of total clearance (CL) to all renal function markers were observed. Body weight and disease status (with or without infection) were also significant covariates. The CL in patients with infection was 26% higher than that in subjects without infection. The fTMIC values were more than 75% in all patients (and were 100% in most patients), suggesting that a sufficient exposure to cefiderocol was provided by the tested dose regimens (2 g every 8 h as the standard dose regimen) for the treatment of cUTI or AUP caused by Gram-negative pathogens. PMID:29038272

Urinary tract infection in children after cardiac surgery: Incidence, causes, risk factors and outcomes in a single-center study.

PubMed

Kabbani, Mohamed S; Ismail, Sameh R; Fatima, Anis; Shafi, Rehana; Idris, Julinar A; Mehmood, Akhter; Singh, Reetam K; Elbarabry, Mahmoud; Hijazi, Omar; Hussein, Mohamed A

2016-01-01

Nosocomial urinary tract infection (UTI) increases hospitalization, cost and morbidity. In this cohort study, we aimed to determine the incidence, risk factors, etiology and outcomes of UTIs in post-operative cardiac children. To this end, we studied all post-operative patients admitted to the Pediatric Cardiac Intensive Care Unit (PCICU) in 2012, and we divided the patients into two groups: the UTI (UTI group) and the non-UTI (control group). We compared both groups for multiple peri-operative risk factors. We included 413 children in this study. Of these, 29 (7%) had UTIs after cardiac surgery (UTI group), and 384 (93%) were free from UTIs (control group). All UTI cases were catheter-associated UTIs (CAUTIs). A total of 1578 urinary catheter days were assessed in this study, with a CAUTI density rate of 18 per 1000 catheter days. Multivariate logistic regression analysis demonstrated the following risk factors for CAUTI development: duration of urinary catheter placement (p<0.001), presence of congenital abnormalities of kidney and urinary tract (CAKUT) (p<0.0041) and the presence of certain syndromes (Down, William, and Noonan) (p<0.02). Gram-negative bacteria accounted for 63% of the CAUTI. The main causes of CAUTI were Klebsiella (27%), Candida (24%) and Escherichia coli (21%). Resistant organisms caused 34% of CAUTI. Two patients (7%) died in the UTI group compared with the one patient (0.3%) who died in the control group (p<0.05). Based on these findings, we concluded that an increased duration of the urinary catheter, the presence of CAKUT, and the presence of syndromes comprised the main risk factors for CAUTI. Gram-negative organisms were the main causes for CAUTI, and one-third of them found to be resistant in this single-center study. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Clinicomicrobiological profile of endophthalmitis: A 10 year experience in a Tertiary Care Center in North India.

PubMed

Satpathy, Gita; Nayak, Niranjan; Wadhwani, Meenakshi; Venkwatesh, Pradeep; Kumar, Atul; Sharma, Yograj; Sreenivas, Vishnu

2017-01-01

To determine the clinicomicrobiological profile of infectious agents and their antibiotic susceptibility in different type of endophthalmitis. A retrospective review of clinical and microbiological records from January 2001 to December 2010, was performed in 1110 patients diagnosed with different type of endophthalmitis (postoperative, posttraumatic, endogenous and post keratitis) to record the demographic details, clinical presentations; microbiological agents isolated with their antimicrobial sensitivity pattern. Antimicrobial susceptibility testing for various culture positive isolates (bacterial/fungal) was performed by the disc diffusion technique. Out of the 1110 intra-ocular specimens processed, 384 (34.6%) were positive for bacteria. S epidermidis was the most predominant isolate accounting for 42.7% of all bacteria obtained, followed by Pseudomonas aeruginosa (24.5%). Besides Pseudomonas, Acinetobacter spp. were the next common gram negative bacilli detected (8.3%) followed by Klebsiella, E. coli, Enterobacter and Alkaligenes in 2.6%, 0.8%, 0.8% and 0.5% cases respectively. The predominant fungal species were Aspergillus spp., in 36.1%, followed by Fusarium spp. in 26.4% cases. Overall susceptibility pattern in our study showed that gram positive bacteria were most susceptible to glycopeptides like vancomycin (80-100%) and fluoroquinolones (87-91%). The sensitivity pattern of gram negative organisms like Pseudomonas and Klebsiella towards fluoroquinolones ranged between 61% - 82%. S epidermidis was the most common bacteria isolated in postoperative and posttraumatic endophthalmitis, Pseudomonas aeruginosa was the most common bacterial isolated in posttraumatic endophthalmitisAmongst fungi Aspergillus was the most common organism.

The effects of antiperspirant on the perineal skin flora of patients with spinal cord injury.

PubMed

Montgomerie, J Z; Gilmore, D S; Graham, I E; Schick, D G

1988-07-01

The relationship of pH and moisture to Pseudomonas aeruginosa and Klebsiella pneumoniae colonization of the perineal skin was studied in male patients with spinal cord injury. The increased pH of the perineal skin was significantly associated with the presence of P. aeruginosa but not other bacterial species. No correlation between colonization and moisture or pH and moisture was found. An antiperspirant produced a significant reduction in the number of total aerobic bacteria, total gram-negative bacilli, P. aeruginosa and K. pneumoniae over a 24-h period. Long-term use of the antiperspirant for 10 days did not alter the persistence of P. aeruginosa of the same serotypes on the perineum.

Two Cases of Bacteremia Due to Roseomonas mucosa.

PubMed

Kim, Yu Kyung; Moon, Jung Suk; Song, Kyung Eun; Lee, Won Kil

2016-07-01

Roseomonas is a genus of pink-pigmented nonfermentative bacilli. These slow-growing, gram-negative cocobacilli form pink-colored colonies on sheep blood agar. They differ from other pink-pigmented nonfermenters, including Methylobacterium, in morphology, biochemical characteristics, and DNA sequence. Roseomonas strains are rarely isolated in clinical laboratories; therefore, we report two cases in order to improve our ability to identify these pathogens. We isolated two strains of Roseomonas mucosa from the venous blood cultures of two patients, an 84-yr-old woman with common bile duct obstruction and a 17-yr-old male with acute myeloid leukemia who had an indwelling central-venous catheter for chemotherapy. The isolated strains were confirmed as R. mucosa by 16S rRNA sequencing.

Two Cases of Bacteremia Due to Roseomonas mucosa

PubMed Central

Kim, Yu Kyung; Moon, Jung Suk; Song, Kyung Eun

2016-01-01

Roseomonas is a genus of pink-pigmented nonfermentative bacilli. These slow-growing, gram-negative cocobacilli form pink-colored colonies on sheep blood agar. They differ from other pink-pigmented nonfermenters, including Methylobacterium, in morphology, biochemical characteristics, and DNA sequence. Roseomonas strains are rarely isolated in clinical laboratories; therefore, we report two cases in order to improve our ability to identify these pathogens. We isolated two strains of Roseomonas mucosa from the venous blood cultures of two patients, an 84-yr-old woman with common bile duct obstruction and a 17-yr-old male with acute myeloid leukemia who had an indwelling central-venous catheter for chemotherapy. The isolated strains were confirmed as R. mucosa by 16S rRNA sequencing. PMID:27139611

Antimicrobial resistance in Gram-positive bacteria from Timorese River Buffalo (Bubalus bubalis) skin microbiota.

PubMed

Oliveira, Manuela; Monteiro, José L; Rana, Sílvia; Vilela, Cristina L

2010-06-01

The Timorese River Buffalo (Bubalus bubalis) plays a major role in the East Timor economy, as it is an important source of animal protein in human nutrition. They are widely spread throughout the country and are in direct contact with the populations. In spite of this proximity, information on their microbiota is scarce. This work aimed at characterizing the skin microbiota of the East Timorese River Buffalo and its antimicrobial resistance profile. Skin swab samples were taken from 46 animals in surveys conducted in three farms located in "Suco de Nairete", Lospalos district, during July and August 2006. Bacteria were isolated and identified according to conventional microbiological procedures. A total of 456 isolates were obtained, including Gram-positive (n = 243) and Gram-negative (n = 213) bacteria. Due to their importance as potential pathogens and as vehicles for antimicrobial resistance transmission, Gram-positive cocci (n = 27) and bacilli (n = 77) isolates were further characterized, and their antimicrobial resistance profile determined by the disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines. This study shows the high bacterial diversity of B. bubalis skin microbiota, representing an important first step towards understanding its importance and epidemiologic role in animal health. It also points out the potential role of these animals as vectors of antimicrobial resistant bacteria dissemination and the importance of antimicrobial resistance monitoring in developing countries.

Quinolone-based antibacterial chemoprophylaxis in neutropenic patients: effect of augmented gram-positive activity on infectious morbidity. National Cancer Institute of Canada Clinical Trials Group.

PubMed

Bow, E J; Mandell, L A; Louie, T J; Feld, R; Palmer, M; Zee, B; Pater, J

1996-08-01

To determine whether augmented quinolone-based antibacterial prophylaxis in neutropenic patients with cancer reduces infections caused by gram-positive cocci and preserves the protective effect against aerobic gram-negative bacilli. Open, randomized, controlled, multicenter clinical trial. Centers participating in the National Cancer Institute of Canada Clinical Trials Group. 111 eligible and evaluable patients hospitalized for severe neutropenia (neutrophil count < 0.5 x 10(9)/L lasting at least 14 days) who were receiving cytotoxic therapy for acute leukemia or bone marrow autografting. One of three oral antibacterial prophylactic regimens (norfloxacin, 400 mg every 12 hours; ofloxacin, 400 mg every 12 hours; or ofloxacin, 400 mg, plus rifampin, 300 mg every 12 hours) beginning with cytotoxic therapy. Incidence and cause of suspected or proven infection. Microbiologically documented overall infection rates for norfloxacin, ofloxacin, and ofloxacin plus rifampin were 47%, 24%, and 9%, respectively (P < 0.001). Corresponding rates were 24%, 13%, and 3%, respectively for staphylococcal bacteremia (P = 0.03) and, 21%, 3%, and 3%, respectively for streptococcal bacteremia (P < 0.01). The pattern of bacteremia suggested that rifampin played a role in suppressing staphylococcal infection. Both ofloxacin alone and ofloxacin plus rifampin had a clinically significant antistreptococcal effect. Aerobic gram-negative rods were cleared from rectal surveillance cultures in all patients after a median of 5.5 days and caused infection in only one patient (0.9%). The reductions in the number of microbiologically documented infections among ofloxacin recipients and ofloxacin plus rifampin recipients were offset by concomitant increases in the number of unexplained fevers (24% of norfloxacin recipients, 53% of ofloxacin recipients, and 49% of ofloxacin plus rifampin recipients; P = 0.02). No statistically significant difference was found among the treatment arms with respect to the overall incidence of febrile neutropenic episodes as defined for this trial (79% for the norfloxacin group, 82% for the ofloxacin group, and 77% for the ofloxacin plus rifampin group). Quinolone-based antibacterial chemoprophylaxis protected patients from aerobic gram-negative bacillary infections. Augmentation of the gram-positive activity reduced the incidence of gram-positive infections but did not influence the overall incidence of febrile neutropenic episodes.

Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract

PubMed Central

Kline, Kimberly A.; Lewis, Amanda L.

2015-01-01

Gram-positive bacteria are a common cause of urinary tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI. PMID:27227294

Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract.

PubMed

Kline, Kimberly A; Lewis, Amanda L

2016-04-01

Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.

Microbial investigation of biofilms recovered from endotracheal tubes using sonication in intensive care unit pediatric patients.

PubMed

Ferreira, Thiago de Oliveira; Koto, Rafael Yoshio; Leite, Gabriel Fialkovitz da Costa; Klautau, Giselle Burlamaqui; Nigro, Stanley; Silva, Cely Barreto da; Souza, Ana Paula Idalgo da Fonseca; Mimica, Marcelo Jenne; Cesar, Regina Grigolli; Salles, Mauro José Costa

2016-01-01

To compare cultured microorganisms identified on endotracheal tubes biofilms through sonication technique with traditional tracheal aspirate collected at extubation of pediatric intensive care unit patients. Demographic and epidemiological data were analyzed to identify factors possibly related with the microbiological profile of the two collection methods. Associations between categorical and continuous variables were analyzed using the chi-square or Fisher's exact test, or Student's t test. p-Value <0.05 were considered significant. Thirty endotracheal tubes and tracheal aspirates samples from 27 subjects were analyzed. Only one patient presented the clinical diagnosis of ventilator-associated pneumonia. Overall, 50% of bacteria were Gram-negative bacilli, followed by Gram-positive bacteria in 37%, and fungi in 10%. No statistically significant difference on the distribution of Gram-positive or Gram-negative bacteria (p=0.996), and fungi (p=0.985) were observed between the collection methods. Pseudomonas spp. was the most frequent microorganism identified (23.8%), followed by Streptococcus spp. (18.5%), Acinetobacter spp. (15.9%), coagulase-negative staphylococci (11.2%), and Klebsiella spp. (8.6%). Concordant results between methods amounted to 83.3%. Pseudomonas aeruginosa and Acinetobacter baumannii showed carbapenem resistance in 50% and 43.7% of the isolates, respectively. In general, cultures after endotracheal tubes sonication (non-centrifuged sonication fluid and centrifuged sonication fluid) yielded bacteria with higher rates of antimicrobial resistance compared to tracheal aspirates cultures. Additionally, in 12 subjects (40%), we observed discrepancies regarding microbiologic profiles of cultures performed using the collection methods. Our study demonstrated that sonication technique can be applied to ET biofilms to identify microorganisms attached to their surface with a great variety of species identified. However, we did not find significant differences in comparison with the traditional tracheal aspirate culture approach. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

Bacteriological Profile of Isolates From Urine Samples in Patients of Benign Prostatic Hyperplasia and or Prostatitis Showing Lower Urinary Tract Symptoms.

PubMed

Mishra, Prem Prakash; Prakash, Ved; Singh, Kashmir; Mog, H; Agarwal, Sumit

2016-10-01

The incidence of Benign Prostatic Hyperplasia (BPH) or Prostatitis is increasing considerably worldwide. The Lower Urinary Tract Symptoms (LUTS) due to bacterial aetiology are one of the common factors for the complications among the patients. To determine the bacterial agents and their antibiotic sensitivity pattern from the urine samples of patients of BPH or Prostatitis showing symptoms of LUTS. The cross-sectional study was carried out in the Department of Microbiology of Rohilkhand Medical College and Hospital of Northern India from June 2014 to May 2015. A total of 105 urine specimens from patients of BPH and/ or Prostatitis were cultured by a semi-quantitative method. The isolated bacteria were identified by colony morphology, Gram's staining, motility and biochemical tests. Antibiotic sensitivity was done according to the CLSI 2007 guidelines by disc diffusion method. Data was analysed by SPSS and Microsoft office 2007. Proportions and percentages were used as statistical measures. The urine cultures from patients with BPH and or chronic Prostatitis, showed n=66/105 (62.85%) culture positivity. Out of 66 isolates the frequency was in following order Escherichia coli 21/66 (31.81%), Klebsiella spp 19/66 (28.78%), Staphylococcus aureus 11/66 (16.66%), Pseudomonas aeruginosa (10.60%), Proteus spp, Enterococcus spp, Acinetobacter spp and Citrobacter spp. The most susceptible 1 st , 2 nd and 3 rd line antibiotics for Gram negative isolates were ampicillin, amikacin and tigecycline respectively. Amongst the Gram positive isolates, the susceptible 1 st , 2 nd and 3 rd line antibiotics were cefoxitin, vancomycin, teicoplanin and linezolid. Multidrug resistance was seen in Escherichia coli (n=6), Klebsiella spp (n=7), Pseudomonas aeruginosa (n=4) and Staphylococcus aureus (n=3). Based on the above findings we can say that accurate aetiology of the LUTS among the patients of BPH and/or Prostatitis is warranted to initiate the therapeutic management. Based on our study we state that the prime pathogens are E.coli , Klebsiella among Gram negative isolates and S. aureus among Gram positive. The most sensitive drugs are aminoglycosides, tetracyclines and carbepenems for Gram neagtive isolates and oxazolidinones and glycopeptides among Gram positive isolates.

Complicated urinary tract infections: practical solutions for the treatment of multiresistant Gram-negative bacteria.

PubMed

Pallett, Ann; Hand, Kieran

2010-11-01

Resistance in Gram-negative bacteria has been increasing, particularly over the last 6 years. This is mainly due to the spread of strains producing extended-spectrum β-lactamases (ESBLs) such as CTX-M enzymes or AmpC β-lactamases. Many of the isolates producing these enzymes are also resistant to trimethoprim, quinolones and aminoglycosides, often due to plasmid co-expression of other resistance mechanisms. CTX-M-producing Escherichia coli often occurs in the community and as E. coli is one of the commonest organisms causing urinary tract infections (UTIs) the choice of agents to treat these infections is diminishing. Novel combinations of antibiotics are being used in the community and broad-spectrum agents such as carbapenems are being used increasingly as empirical treatment for severe infections. Of particular concern therefore are reports in the UK of organisms that produce carbapenemases. As resistance is becoming more widespread, prudent use of antimicrobials is imperative and, as asymptomatic bacteriuria is typically benign in the elderly, antibiotics should not be prescribed without clinical signs of UTI. The use of antibiotics as suppressive therapy or long-term prophylaxis may no longer be defensible.

Evaluation of the automated urine particle analyzer UF-1000i screening for urinary tract infection in nonpregnant women.

PubMed

Dai, Qingkai; Jiang, Yongmei; Shi, Hua; Zhou, Wei; Zhou, Shengjie; Yang, Hui

2014-01-01

Urinary tract infection (UTI) is a widespread disease in women. Urine culture is still the "gold standard" diagnostic test for UTI, but most of them are negative. To reduce unnecessary culture, we evaluated the automated urine particle analyzer UF-1000i screening for UTI in nonpregnant women. The urine specimens submitted to our laboratory were submitted for culture and tested by the Sysmex UF-1000i. Bacteria and white blood cell (WBC) counts were compared to standard urine culture results to assess the best cutoff values. In this study, 272 urine samples were included, of which 98 (36.0%) were culture positive with a bacterial cutoff value of 10 x 10(5) CFU/mL. A combination of bacterial (> 95/microL) and/or WBC count (> 24/microL) provided the best screening for UTI, with a sensitivity of 0.99 and a specificity of 0.82 compared with the urine culture. Sysmex UF-1000i could be used as a screening test for UTI in nonpregnant women. According to the distribution and range of the bacterial scattergram, we could primarily identify and differentiate between Gram-negative and Gram-positive bacteria.

In vitro activity of imipenem/relebactam against Gram-negative ESKAPE pathogens isolated in 17 European countries: 2015 SMART surveillance programme.

PubMed

Karlowsky, James A; Lob, Sibylle H; Kazmierczak, Krystyna M; Hawser, Stephen P; Magnet, Sophie; Young, Katherine; Motyl, Mary R; Sahm, Daniel F

2018-04-11

Relebactam is an inhibitor of class A β-lactamases, including KPC β-lactamases, and class C β-lactamases, and is currently under clinical development in combination with imipenem. The objective of the current study was to evaluate the in vitro activity of imipenem/relebactam against Gram-negative ESKAPE pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) submitted by clinical laboratories in 17 European countries to the Study for Monitoring Antimicrobial Resistance Trends (SMART) global surveillance programme in 2015. MICs were determined using the CLSI standard broth microdilution method and interpreted using EUCAST clinical breakpoints. Relebactam was tested at a fixed concentration of 4 mg/L in combination with doubling dilutions of imipenem. Imipenem/relebactam MICs were interpreted using breakpoints for imipenem. Rates of susceptibility to imipenem and imipenem/relebactam for isolates of P. aeruginosa (n = 1705), K. pneumoniae (n = 1591) and Enterobacter spp. (n = 772) were 72.0/94.7%, 88.7/94.8% and 95.6/96.8%, respectively. Relebactam restored imipenem susceptibility to 81.1%, 54.2% and 26.5% of imipenem-non-susceptible isolates of P. aeruginosa (n = 477), K. pneumoniae (n = 179) and Enterobacter spp. (n = 34). Most imipenem/relebactam-non-susceptible isolates carried MBLs, OXA-48 or GES carbapenemases. Relebactam did not increase the number of isolates of A. baumannii (n = 486) susceptible to imipenem. Relebactam restored susceptibility to imipenem for the majority of imipenem-non-susceptible isolates of P. aeruginosa and K. pneumoniae tested as well as some isolates of imipenem-non-susceptible Enterobacter spp. Based on our results, imipenem/relebactam appears to be a promising therapeutic option for treating patients with infections caused by antimicrobial-resistant Gram-negative bacilli.

Nosocomial Bloodstream Infections in Brazilian Pediatric Patients: Microbiology, Epidemiology, and Clinical Features

PubMed Central

Pereira, Carlos Alberto Pires; Marra, Alexandre R.; Camargo, Luis Fernando Aranha; Pignatari, Antônio Carlos Campos; Sukiennik, Teresa; Behar, Paulo Renato Petersen; Medeiros, Eduardo Alexandrino Servolo; Ribeiro, Julival; Girão, Evelyne; Correa, Luci; Guerra, Carla; Carneiro, Irna; Brites, Carlos; Reis, Marise; de Souza, Marta Antunes; Tranchesi, Regina; Barata, Cristina U.; Edmond, Michael B.

2013-01-01

Background Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality and are the most frequent type of nosocomial infection in pediatric patients. Methods We identified the predominant pathogens and antimicrobial susceptibilities of nosocomial bloodstream isolates in pediatric patients (≤16 years of age) in the Brazilian Prospective Surveillance for nBSIs at 16 hospitals from 12 June 2007 to 31 March 2010 (Br SCOPE project). Results In our study a total of 2,563 cases of nBSI were reported by hospitals participating in the Br SCOPE project. Among these, 342 clinically significant episodes of BSI were identified in pediatric patients (≤16 years of age). Ninety-six percent of BSIs were monomicrobial. Gram-negative organisms caused 49.0% of these BSIs, Gram-positive organisms caused 42.6%, and fungi caused 8.4%. The most common pathogens were Coagulase-negative staphylococci (CoNS) (21.3%), Klebsiella spp. (15.7%), Staphylococcus aureus (10.6%), and Acinetobacter spp. (9.2%). The crude mortality was 21.6% (74 of 342). Forty-five percent of nBSIs occurred in a pediatric or neonatal intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 95 patients (27.8%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (66.4%). Methicillin resistance was detected in 37 S. aureus isolates (27.1%). Of the Klebsiella spp. isolates, 43.2% were resistant to ceftriaxone. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 42.9% and 21.4%, respectively, were resistant to imipenem. Conclusions In our multicenter study, we found a high mortality and a large proportion of gram-negative bacilli with elevated levels of resistance in pediatric patients. PMID:23861860

Comparison of two commercial carbapenemase gene confirmatory assays in multiresistant Enterobacteriaceae and Acinetobacter baumannii-complex.

PubMed

Rösner, Stephan; Gehlweiler, Kevin; Küsters, Uta; Kolbert, Mathias; Hübner, Kirsten; Pfennigwerth, Niels; Mack, Dietrich

2018-01-01

Multidrug-resistant Gram-negative bacilli (MDR-GNB) producing carbapenemases are increasing at an alarming speed. Rapid confirmation of carbapenemase type will be an important diagnostic step in clinical microbiology laboratories not only to reduce the risk of transmissions but also for optimising antibiotic therapy in the future. We compared diagnostic reliability of two commercially available molecular assays (Check-Direct CPE vs. AID line probe assay) for detection and typing of carbapenemase genes in 80 well-characterized isolates of MDR-GNB. Respective strains were isolated in various clinical specimens at our clinical microbiology laboratory. The reference standard included confirmation of carbapenemase-production at the molecular level at the German National Reference Laboratory for Multidrug-resistant Gram-negative bacteria (Ruhr-University Bochum, Germany). 53 Enterobacteriaceae and 27 members of the A. baumannii-complex were used in this study. The tested assays appeared highly reliable to confirm carbapenemase-producing Enterobacteriaceae (CPE) with respective sensitivities of 97.7%, but are currently unsuitable for analysis of members of the A. baumannii-complex. Both assays are easy to perform and rapid tools for confirmation and typing of the most common carbapenemase genes in Enterobacteriaceae. Implementation should be possible for any clinical microbiology laboratory with Check-Direct CPE being easier to handle and having less technological requirements.

First case report of sepsis caused by Rhizobium pusense in Japan.

PubMed

Kuchibiro, Tomokazu; Hirayama, Katsuhisa; Houdai, Katsuyuki; Nakamura, Tatsuya; Ohnuma, Kenichirou; Tomida, Junko; Kawamura, Yoshiaki

2018-01-01

Species of the genus Rhizobium are opportunistic, usually saprophytic, glucose-non-fermenting, Gram-negative bacilli found in agricultural soil. Rhizobium pusense infections are the least common Rhizobium infections and have low incidence. Herein, we report the first case of sepsis with R. pusense in Japan in a 67-year-old Japanese woman with a history of hyperlipidaemia, hypertension, diabetes, hypothyroidism and osteoporosis. She had undergone cerebrovascular treatment because she was diagnosed with a subarachnoid haemorrhage. The results of postoperative blood culture showed oxidase-positive, urease-positive, non-lactose-fermenting Gram-stain-negative rods. Using the Vitek2 system, the isolate was distinctly identified as Rhizobium radiobacter . However, 16S rRNA gene sequencing showed 99.93 % similarity with the type strain of R. pusense and 99.06 % similarity with the type strain of R. radiobacter . Additional gene sequencing analysis using recA (97.2 %) and atpD (96.2 %) also showed that the isolated strain is most closely related to R. pusense . The patient was cured by treatment using intravenous meropenem (3 g/d) for 4 weeks and was discharged safely. The definite source of sepsis was unknown. However, the possibility of having been infected through the catheter during the cerebrovascular operation was speculated.

The Assessment of Oral Microflora Exposed to 3% Ethanolic Extract of Brazilian Green Propolis Preparation Used for Hygiene Maintenance following Minor Oral Surgeries

PubMed Central

Morawiec, Tadeusz; Wojtyczka, Robert D.; Niedzielska, Iwona; Bubiłek-Bogacz, Anna; Wróbel, Jacek; Tanasiewicz, Marta; Wesołowski, Piotr; Król, Wojciech

2015-01-01

The aim of this study was to investigate the influence of a topically administered hygienic preparation containing a 3% ethanolic extract of Brazilian green propolis (EEP-B) on oral microflora spectrum changes in a group of patients who underwent common oral surgery procedures. Two gel samples were compared: the tested gel containing an active ingredient, that is, a 3% EEP-B (gel GA), and a placebo as the negative control (gel GC). The collection of microbiological material included 14 patients requiring surgical extraction of wisdom molars and short endosseous implant installation. Clinical examinations were carried out as follow-up, that is, baseline and after 5-6 weeks' time. During the first and subsequent assessment, swabs were taken from the mucosal surface. The number of microorganism species was found to have increased following the application of GC gel over the period of 5-6 weeks. This mainly affected Gram-positive rods and bacilli as well as Gram-negative rods. Application of the GA gel enriched with 3% EEP-B caused a profound reduction in the amount of Neisseria spp. and Bifidobacterium spp. strains. Elimination of seven species of microorganisms was observed: Streptococcus acidominimus, Streptococcus oralis, Staphylococcus epidermidis, Veillonella parvula, Bifidobacterium breve, Bifidobacterium longum, and Lactobacillus acidophilus. PMID:26380300

Treatment strategy for a multidrug-resistant Klebsiella UTI.

PubMed

Fleming, Erin; Heil, Emily L; Hynicka, Lauren M

2014-01-01

To describe the management strategy for a multidrug-resistant (MDR) Klebsiella urinary tract infection (UTI). A 69-year-old Caucasian woman with a past medical history of recurrent UTIs and a right-lung transplant presented with fever to 101.4°F, chills, malaise, and cloudy, foul-smelling urine for approximately 1 week. She was found to have a MDR Klebsiella UTI that was sensitive to tigecycline and cefepime. To further evaluate the degree of resistance Etest minimum inhibitory concentrations were requested for cefepime, amikacin, meropenem, and ertapenem. The patient received a 14-day course of amikacin, which resulted in resolution of her symptoms. One month later, the patient's UTI symptoms returned. The urine culture again grew MDR Klebsiella, sensitive only to tigecycline. Fosfomycin was initiated and resulted in limited resolution of her symptoms. Colistin was started, however, therapy was discontinued on day 5 secondary to the development of acute kidney injury. Despite the short course of therapy, the patient's symptoms resolved. The case presented lends itself well to numerous discussion items that are important to consider when determining optimal treatment for MDR Gram-negative bacilli (GNBs). Susceptibility testing is an important tool for optimizing antibiotic therapy, however, automated systems may overestimate the susceptibility profile for a MDR GNB. Treatment strategies evaluated to treat MDR GNB, include combination therapy with a carbepenem and synergy using polymyxin. We have described the management strategy for a MDR Klebsiella UTI, the consequences of the initial management strategy, and potential strategies to manage these types of infections in future patients.

Phosphonopeptides as Antibacterial Agents: Alaphosphin and Related Phosphonopeptides

PubMed Central

Allen, John G.; Atherton, Frank R.; Hall, Michael J.; Hassall, Cedric H.; Holmes, Simon W.; Lambert, Robert W.; Nisbet, Louis J.; Ringrose, Peter S.

1979-01-01

Alaphosphin, l-alanyl-l-1-aminoethylphosphonic acid, was selected from a range of phosphonopeptides for evaluation in humans on the basis of its antibacterial activity, pharmacokinetics, and stability to intestinal and kidney peptidases. In vitro, the antibacterial action was antagonized by small peptides, resulting in low activity on peptone media. On an antagonist-free medium alaphosphin was bactericidal and rapidly lysed most susceptible gram-negative bacteria, but it was largely bacteriostatic and essentially nonlytic against gram-positive organisms. Its spectrum included most strains normally isolated from urinary tract infections, but potency was greatly reduced by very high inoculum levels and by alkaline pH. Although strains of Proteus and Pseudomonas were less susceptible to alaphosphin than were other common gram-negative bacteria, like other species they formed spheroplasts when exposed under appropriate conditions. Alaphosphin was equally effective against penicillin-susceptible and -resistant strains and showed no cross-resistance with known antibiotics. Good synergy and increased bactericidal activity were demonstrated with combinations of alaphosphin and d-cycloserine or β-lactam antibiotics. Images PMID:43113

Isolation and whole genome analysis of endospore-forming bacteria from heroin.

PubMed

Kalinowski, Jörn; Ahrens, Björn; Al-Dilaimi, Arwa; Winkler, Anika; Wibberg, Daniel; Schleenbecker, Uwe; Rückert, Christian; Wölfel, Roman; Grass, Gregor

2018-01-01

Infections caused by endospore-forming bacteria have been associated with severe illness and death among persons who inject drugs. Analysis of the bacteria residing in heroin has thus been biased towards species that affect human health. Similarly, exploration of the bacterial diversity of seized street market heroin correlated with the skin microflora of recreational heroin users insofar as different Staphylococus spp. or typical environmental endospore formers including Bacillus cereus and other Bacilli outside the B. cereus sensu lato group as well as diverse Clostridia were identified. In this work 82 samples of non-street market ("wholesale") heroin originating from the German Federal Criminal Police Office's heroin analysis program seized during the period between 2009 and 2014 were analyzed for contaminating bacteria. Without contact with the end user and with only little contaminations introduced by final processing, adulteration and cutting this heroin likely harbors original microbiota from the drug's original source or trafficking route. We found this drug to be only sparsely populated with retrievable heterotrophic, aerobic bacteria. In total, 68 isolates were retrieved from 49 out of 82 samples analyzed (60% culture positive). All isolates were endospore-forming, Gram-positive Bacilli. Completely absent were non-endospore-formers or Gram-negatives. The three most predominant species were Bacillus clausii, Bacillus (para)licheniformis, and Terribacillus saccharophilus. Whole genome sequencing of these 68 isolates was performed using Illumina technology. Sequence data sets were assembled and annotated using an automated bioinformatics pipeline. Average nucleotide identity (ANI) values were calculated for all draft genomes and all close to identical genomes (ANI>99.5%) were compared to the forensic data of the seized drug, showing positive correlations that strongly warrant further research on this subject. Copyright © 2017 Elsevier B.V. All rights reserved.

A Comparative Evaluation on Antimicrobial Effect of Honey, Neem Leaf Extract and Sodium Hypochlorite as Intracanal Irrigant: An Ex-Vivo Study

PubMed Central

Narayanan, Retna Kumari; Vadakkepurayil, Kannan

2016-01-01

Introduction The major determinant of the success of root canal treatment depends on meticulous disinfection of the root canal using intracanal irrigants. The most commonly used root canal irrigant is sodium hypochlorite which has disadvantages of cytotoxicity and unpleasant taste. So there is a need to identify a more biocompatible root canal irrigant. Aim The aim of this ex-vivo study was to evaluate the efficacy of 40% honey, 100% neem leaf extract and 5.25% sodium hypochlorite as an intracanal irrigant against the isolated microorganisms from infected root canal. Materials and Methods The samples were collected from infected root canals of 60 primary molar teeth indicated for pulpectomy. Alpha hemolytic Streptococci, gram negative bacilli, Candida, Staphylococci, Lactobacilli, Enterococci, Spore bearing gram positive bacilli and Micrococci were the microorganisms isolated from the samples. The zone of inhibition against the microbial growth was measured by agar well diffusion method. Statistical analysis was done by Repeated Analysis of Variance (ANOVA) and Bonferroni method. Results Statistical analysis showed that the means of the zones of inhibition measured in this study were 18.56mm, 2.09mm and 1.62mm for sodium hypochlorite, 100% neem leaf extract and 40% honey respectively. The significance was greater between sodium hypochlorite and the other two agents as p-value was <0.001. Conclusion The results indicated that 5.25% sodium hypochlorite is more effective as root canal irrigant when compared with 100% neem leaf extract and 40% honey. It was also observed that 100% neem leaf extract has greater antimicrobial effect than 40% honey. PMID:27656571

Red blood cell distribution width is an independent predictor of mortality in patients with gram-negative bacteremia.

PubMed

Ku, Nam Su; Kim, Hye-Won; Oh, Hyung Jung; Kim, Yong Chan; Kim, Min Hyung; Song, Je Eun; Oh, Dong Hyun; Ahn, Jin Young; Kim, Sun Bean; Jeong, Su Jin; Han, Sang Hoon; Kim, Chang Oh; Song, Young Goo; Kim, June Myung; Choi, Jun Yong

2012-08-01

Red blood cell distribution width (RDW) is known to be a predictor of severe morbidity and mortality in some chronic diseases such as congestive heart failure. However, to our knowledge, little is known about RDW as a predictor of mortality in patients with Gram-negative bacteremia, a major nosocomial cause of intra-abdominal infections, urinary tract infections, and primary bacteremia. Therefore, we investigated whether RDW is an independent predictor of mortality in patients with Gram-negative bacteremia. Clinical characteristics, laboratory parameters, and outcomes of 161 patients with Gram-negative bacteremia from November 2010 to March 2011 diagnosed at Severance Hospital, Yonsei University College of Medicine, Seoul, Korea, were retrospectively analyzed. The main outcome measure was 28-day all-cause mortality. The 28-day mortality rate was significantly higher in the increased RDW group compared with the normal RDW group (P < 0.001). According to multivariate Cox proportional hazard analysis, RDW levels at the onset of bacteremia (per 1% increase, P = 0.036), the Charlson index (per 1-point increase, P < 0.001), and the Sequential Organ Failure Assessment score (per 1-point increase, P = 0.001) were independent risk factors for 28-day mortality. Moreover, the nonsurvivor group had significantly higher RDW levels 72 h after the onset of bacteremia than did the survivor group (P = 0.001). In addition, the area under the curve of RDW at the onset of bacteremia, the 72-h RDW, and the Sequential Organ Failure Assessment score for 28-day mortality were 0.764 (P = 0.001), 0.802 (P < 0.001), and 0.703 (P = 0.008), respectively. Red blood cell distribution width at the onset of bacteremia was an independent predictor of mortality in patients with Gram-negative bacteremia. Also, 72-h RDW could be a predictor for all-cause mortality in patients with Gram-negative bacteremia.

A Targeted Infection Prevention Intervention in Nursing Home Residents With Indwelling Devices

PubMed Central

Mody, Lona; Krein, Sarah L.; Saint, Sanjay K.; Min, Lillian C.; Montoya, Ana; Lansing, Bonnie; McNamara, Sara E.; Symons, Kathleen; Fisch, Jay; Koo, Evonne; Rye, Ruth Anne; Galecki, Andrzej; Kabeto, Mohammed U.; Fitzgerald, James T.; Olmsted, Russell N.; Kauffman, Carol A.; Bradley, Suzanne F.

2015-01-01

IMPORTANCE Indwelling devices (eg, urinary catheters and feeding tubes) are often used in nursing homes (NHs). Inadequate care of residents with these devices contributes to high rates of multidrug-resistant organisms (MDROs) and device-related infections in NHs. OBJECTIVE To test whether a multimodal targeted infection program (TIP) reduces the prevalence of MDROs and incident device-related infections. DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial at 12 community-based NHs from May 2010 to April 2013. Participants were high-risk NH residents with urinary catheters, feeding tubes, or both. INTERVENTIONS Multimodal, including preemptive barrier precautions, active surveillance for MDROs and infections, and NH staff education. MAIN OUTCOMES AND MEASURES The primary outcome was the prevalence density rate of MDROs, defined as the total number of MDROs isolated per visit averaged over the duration of a resident's participation. Secondary outcomes included new MDRO acquisitions and new clinically defined device-associated infections. Data were analyzed using a mixed-effects multilevel Poisson regression model (primary outcome) and a Cox proportional hazards model (secondary outcome), adjusting for facility-level clustering and resident-level variables. RESULTS In total, 418 NH residents with indwelling devices were enrolled, with 34 174 device-days and 6557 anatomic sites sampled. Intervention NHs had a decrease in the overall MDRO prevalence density (rate ratio, 0.77; 95% CI, 0.62–0.94). The rate of new methicillin-resistant Staphylococcus aureus acquisitions was lower in the intervention group than in the control group (rate ratio, 0.78; 95% CI, 0.64–0.96). Hazard ratios for the first and all (including recurrent) clinically defined catheter-associated urinary tract infections were 0.54 (95% CI, 0.30–0.97) and 0.69 (95% CI, 0.49–0.99), respectively, in the intervention group and the control group. There were no reductions in new vancomycin-resistant enterococci or resistant gram-negative bacilli acquisitions or in new feeding tube–associated pneumonias or skin and soft-tissue infections. CONCLUSIONS AND RELEVANCE Our multimodal TIP intervention reduced the overall MDRO prevalence density, new methicillin-resistant S aureus acquisitions, and clinically defined catheter-associated urinary tract infection rates in high-risk NH residents with indwelling devices. Further studies are needed to evaluate the cost-effectiveness of this approach as well as its effects on the reduction of MDRO transmission to other residents, on the environment, and on referring hospitals. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01062841 PMID:25775048

Quorum-Quenching and Matrix-Degrading Enzymes in Multilayer Coatings Synergistically Prevent Bacterial Biofilm Formation on Urinary Catheters.

PubMed

Ivanova, Kristina; Fernandes, Margarida M; Francesko, Antonio; Mendoza, Ernest; Guezguez, Jamil; Burnet, Michael; Tzanov, Tzanko

2015-12-16

Bacteria often colonize in-dwelling medical devices and grow as complex biofilm communities of cells embedded in a self-produced extracellular polymeric matrix, which increases their resistance to antibiotics and the host immune system. During biofilm growth, bacterial cells cooperate through specific quorum-sensing (QS) signals. Taking advantage of this mechanism of biofilm formation, we hypothesized that interrupting the communication among bacteria and simultaneously degrading the extracellular matrix would inhibit biofilm growth. To this end, coatings composed of the enzymes acylase and α-amylase, able to degrade bacterial QS molecules and polysaccharides, respectively, were built on silicone urinary catheters using a layer-by-layer deposition technique. Multilayer coatings of either acylase or amylase alone suppressed the biofilm formation of corresponding Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. Further assembly of both enzymes in hybrid nanocoatings resulted in stronger biofilm inhibition as a function of acylase or amylase position in the layers. Hybrid coatings, with the QS-signal-degrading acylase as outermost layer, demonstrated 30% higher antibiofilm efficiency against medically relevant Gram-negative bacteria compared to that of the other assemblies. These nanocoatings significantly reduced the occurrence of single-species (P. aeruginosa) and mixed-species (P. aeruginosa and Escherichia coli) biofilms on silicone catheters under both static and dynamic conditions. Moreover, in an in vivo animal model, the quorum quenching and matrix degrading enzyme assemblies delayed the biofilm growth up to 7 days.

Population Pharmacokinetic Analysis of Cefiderocol, a Parenteral Siderophore Cephalosporin, in Healthy Subjects, Subjects with Various Degrees of Renal Function, and Patients with Complicated Urinary Tract Infection or Acute Uncomplicated Pyelonephritis.

PubMed

Kawaguchi, Nao; Katsube, Takayuki; Echols, Roger; Wajima, Toshihiro

2018-02-01

Cefiderocol, a novel parenteral siderophore cephalosporin, exhibits potent efficacy against most Gram-negative bacteria, including carbapenem-resistant strains. The aim of this study was to perform a population pharmacokinetic (PK) analysis based on plasma cefiderocol concentrations in healthy subjects, subjects with various degrees of renal function, and patients with complicated urinary tract infection (cUTI) or acute uncomplicated pyelonephritis (AUP) caused by Gram-negative pathogens and to calculate the fraction of the time during the dosing interval where the free drug concentration in plasma exceeds the MIC ( fT MIC ). Population PK models were developed with three renal function markers, body surface area-adjusted estimated glomerular filtration rate (eGFR), absolute eGFR, and creatinine clearance, on the basis of 2,571 plasma concentrations from 91 subjects without infection and 238 patients with infection. The population PK models with each renal function marker adequately described the plasma cefiderocol concentrations. Clear relationships of total clearance (CL) to all renal function markers were observed. Body weight and disease status (with or without infection) were also significant covariates. The CL in patients with infection was 26% higher than that in subjects without infection. The fT MIC values were more than 75% in all patients (and were 100% in most patients), suggesting that a sufficient exposure to cefiderocol was provided by the tested dose regimens (2 g every 8 h as the standard dose regimen) for the treatment of cUTI or AUP caused by Gram-negative pathogens. Copyright © 2018 Kawaguchi et al.

Multi-resistant gram negative enteric bacteria causing urinary tract infection among malnourished underfives admitted at a tertiary hospital, northwestern, Tanzania.

PubMed

Ahmed, Maimuna; Moremi, Nyambura; Mirambo, Mariam M; Hokororo, Adolfine; Mushi, Martha F; Seni, Jeremiah; Kamugisha, Erasmus; Mshana, Stephen E

2015-06-19

Infections are common complications occurring in malnourished childrenas a result of impaired immunity. Urinary tract infections (UTI) have been found to be the commonest cause of fever in normal children in developing countries. However, data regarding UTI among malnourished children is limited because in most of time severe and moderately malnourished children are afebrile despite significant bacteriuria. A total of 402 malnourished underfives were enrolled. Demographic and other clinical characteristics were collected using standardized data collection tool. Urine specimens were cultured and interpreted according to standard operating procedures. Data were analyzed using STATA version 11. Out of 402 malnourished underfives, 229 (56.9 %) were male. The median age in months was 17 (IQR; 12-31). Of 402 malnourished underfives, 83 (20.3 %) had significant bacteriuria of gram negative enteric bacteria. Escherichia coli 35/84 and Klebsiella pneumonia 20/84 were predominant bacteria isolated. More than 37 % of isolates were resistant to third generation cephalosporins with all of them exhibiting extended spectrum beta lactamase (ESBL) phenotype. Rates of resistance to ampicillin, amoxillin/clavulanic acid, gentamicin and ciprofloxacin were 82/84 (98.7 %), 47/55 (85.4 %), 45/84 (57.8 %) and 9/84 (10.8 %) respectively. Decrease in age and increase in lymphocytes count were independent factors on multivariate logistic regression analysis found to predict UTI (p<0.05). Multi-resistant gram negative enteric bacteria are common cause of UTI among underfives. A significant number of severe and moderate malnourished children with bacteriuria had no fever. Therefore, routine testing for UTI is emphasized in all malnourished underfives so that appropriate treatment can be initiated.

The role of chiropractic adjusting tables as reservoirs for microbial diseases.

PubMed

Bifero, Antonio E; Prakash, Jaya; Bergin, Jeff

2006-04-01

Our goal was to enumerate the microbial flora on the headrest, armrest, and thoracic portion of chiropractic adjusting tables to determine the presence of pathogenic microorganisms and identify the potential for nosocomial transmission. Defined portions of the headrest, armrest, and thoracoabdominal pieces from 9 chiropractic adjusting tables were randomly sampled using the ACT II culture transport system (Remel, Lenexa, KS). Samples were incubated using standard culture techniques for bacteriology and mycology that included 15 mL of heart infusion agar at 35 degrees C for 24 hours and 15 mL of Sabouraud dextrose agar at 30 degrees C up to 7 days. Identification of microorganisms by biochemical analysis yielded a wide variety of gram-positive (G+) and gram-negative (G-) cocci and bacilli as well as standard fungi. Many were of the genus Staphylococcus. Methicillin-resistant S. aureus (MRSA) isolates were recovered from 2 separate tables. This study supports a growing consensus that those outpatient facilities that do not adhere to strict infection control protocols may become ecological reservoirs of potentially harmful human pathogens.

Levofloxacin for the treatment of community-acquired pneumonia.

PubMed

Lynch, Joseph P; File, Thomas M; Zhanel, George G

2006-10-01

New respiratory fluoroquinolones (FQs), such as levofloxacin, offer many improved qualities over older agents, such as ciprofloxacin. These include retaining excellent Gram-negative bacilli activity, with improved Gram-positive activity. New FQ-like levofloxacin possesses greater bioavailabilty and a longer serum half-life compared with ciprofloxacin, allowing for once-daily dosing, which may improve patient adherence. The high bioavailability of levofloxacin allows for rapid step-down from intravenous administration to oral therapy, minimizing unnecessary hospitalization, which may decrease costs and improve patient quality of life. Levofloxacin has been evaluated for the treatment of community-acquired pneumonia (CAP) in numerous randomized clinical trials. Most published studies have used the 500 mg dose, although more recent studies have investigated the 750 mg dose once daily. These trials demonstrate that levofloxacin is effective and safe for the treatment of CAP, displaying relatively mild adverse effects that are more or less comparable with ciprofloxacin. Levofloxacin has much to offer in terms of bacterial eradication, including for resistant respiratory pathogens. However, ciprofloxacin-resistant organisms are becoming more prevalent so prudence must be exercised when prescribing this agent.

Semisynthetic Penicillin 6-[d(—)-α-Carboxy-3-Thienylacetamido] Penicillanic Acid Active Against Pseudomonas In Vitro

PubMed Central

Neu, H. C.; Winshell, E. B.

1971-01-01

The activity of 6-[d(—)-α-carboxy-3-thienylacetamido] penicillanic acid, BRL2288, was determined against Pseudomonas aeruginosa and various gram-negative bacilli. The majority of Pseudomonas strains (89%) were inhibited by 100 μg of the antibiotic per ml. BRL2288 is twofold more active than carbenicillin against Pseudomonas at 100 μg/ml or less. Among Enterobacteriaceae tested, 87% Enterobacter and 87% of Proteus mirabilis strains were inhibited by 25 μg/ml or less. Indole-positive Proteus were inhibited by 10 μg/ml or less. Fifty-five per cent of ampicillin-resistant Escherichia coli were inhibited by 100 μg/ml. Klebsiella were uniformly resistant. BRL2288 is not hydrolyzed by most resistant Pseudomonas, but it is destroyed by the β-lactamases of E. coli and P. mirabilis. The antibiotic shows synergy with gentamicin but not with penicillinase-resistant penicillins such as cloxacillin. Activity of BRL2288 against gram-positive organisms is two- to eightfold less than that of ampicillin or benzylpenicillin G. PMID:4993233

Gram-negative bacteraemia; a multi-centre prospective evaluation of empiric antibiotic therapy and outcome in English acute hospitals.

PubMed

Fitzpatrick, J M; Biswas, J S; Edgeworth, J D; Islam, J; Jenkins, N; Judge, R; Lavery, A J; Melzer, M; Morris-Jones, S; Nsutebu, E F; Peters, J; Pillay, D G; Pink, F; Price, J R; Scarborough, M; Thwaites, G E; Tilley, R; Walker, A S; Llewelyn, M J

2016-03-01

Increasing antibiotic resistance makes choosing antibiotics for suspected Gram-negative infection challenging. This study set out to identify key determinants of mortality among patients with Gram-negative bacteraemia, focusing particularly on the importance of appropriate empiric antibiotic treatment. We conducted a prospective observational study of 679 unselected adults with Gram-negative bacteraemia at ten acute english hospitals between October 2013 and March 2014. Appropriate empiric antibiotic treatment was defined as intravenous treatment on the day of blood culture collection with an antibiotic to which the cultured organism was sensitive in vitro. Mortality analyses were adjusted for patient demographics, co-morbidities and illness severity. The majority of bacteraemias were community-onset (70%); most were caused by Escherichia coli (65%), Klebsiella spp. (15%) or Pseudomonas spp. (7%). Main foci of infection were urinary tract (51%), abdomen/biliary tract (20%) and lower respiratory tract (14%). The main antibiotics used were co-amoxiclav (32%) and piperacillin-tazobactam (30%) with 34% receiving combination therapy (predominantly aminoglycosides). Empiric treatment was inappropriate in 34%. All-cause mortality was 8% at 7 days and 15% at 30 days. Independent predictors of mortality (p <0.05) included older age, greater burden of co-morbid disease, severity of illness at presentation and inflammatory response. Inappropriate empiric antibiotic therapy was not associated with mortality at either time-point (adjusted OR 0.82; 95% CI 0.35-1.94 and adjusted OR 0.92; 95% CI 0.50-1.66, respectively). Although our study does not exclude an impact of empiric antibiotic choice on survival in Gram-negative bacteraemia, outcome is determined primarily by patient and disease factors. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Gram-stain plus MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry) for a rapid diagnosis of urinary tract infection.

PubMed

Burillo, Almudena; Rodríguez-Sánchez, Belén; Ramiro, Ana; Cercenado, Emilia; Rodríguez-Créixems, Marta; Bouza, Emilio

2014-01-01

Microbiological confirmation of a urinary tract infection (UTI) takes 24-48 h. In the meantime, patients are usually given empirical antibiotics, sometimes inappropriately. We assessed the feasibility of sequentially performing a Gram stain and MALDI-TOF MS mass spectrometry (MS) on urine samples to anticipate clinically useful information. In May-June 2012, we randomly selected 1000 urine samples from patients with suspected UTI. All were Gram stained and those yielding bacteria of a single morphotype were processed for MALDI-TOF MS. Our sequential algorithm was correlated with the standard semiquantitative urine culture result as follows: Match, the information provided was anticipative of culture result; Minor error, the information provided was partially anticipative of culture result; Major error, the information provided was incorrect, potentially leading to inappropriate changes in antimicrobial therapy. A positive culture was obtained in 242/1000 samples. The Gram stain revealed a single morphotype in 207 samples, which were subjected to MALDI-TOF MS. The diagnostic performance of the Gram stain was: sensitivity (Se) 81.3%, specificity (Sp) 93.2%, positive predictive value (PPV) 81.3%, negative predictive value (NPV) 93.2%, positive likelihood ratio (+LR) 11.91, negative likelihood ratio (-LR) 0.20 and accuracy 90.0% while that of MALDI-TOF MS was: Se 79.2%, Sp 73.5, +LR 2.99, -LR 0.28 and accuracy 78.3%. The use of both techniques provided information anticipative of the culture result in 82.7% of cases, information with minor errors in 13.4% and information with major errors in 3.9%. Results were available within 1 h. Our serial algorithm provided information that was consistent or showed minor errors for 96.1% of urine samples from patients with suspected UTI. The clinical impacts of this rapid UTI diagnosis strategy need to be assessed through indicators of adequacy of treatment such as a reduced time to appropriate empirical treatment or earlier withdrawal of unnecessary antibiotics.

Osteomyelitis associated with Nocardiopsis composta in a dog.

PubMed

Salas, Elisa N; Royal, Debra; Kurz, Lance; Loy, J Dustin

2015-05-01

We report the first detection of Nocardiopsis composta in association with osteomyelitis in a young male miniature Australian shepherd dog. Findings included suppurative osteomyelitis containing intralesional Fite's acid fast bacilli, aerobic culture of branching Gram-positive rods, and positive identification via phenotypic analysis and 16S rDNA sequencing.

Epidemic microclusters of blood-culture proven sepsis in very-low-birth weight infants: experience of the German Neonatal Network.

PubMed

Härtel, Christoph; Faust, Kirstin; Avenarius, Stefan; Bohnhorst, Bettina; Emeis, Michael; Gebauer, Corinna; Groneck, Peter; Heitmann, Friedhelm; Hoehn, Thomas; Hubert, Mechthild; Kribs, Angela; Küster, Helmut; Laux, Reinhard; Mögel, Michael; Müller, Dirk; Olbertz, Dirk; Roll, Claudia; Siegel, Jens; Stein, Anja; Vochem, Matthias; Weller, Ursula; von der Wense, Axel; Wieg, Christian; Wintgens, Jürgen; Hemmelmann, Claudia; Simon, Arne; Herting, Egbert; Göpel, Wolfgang

2012-01-01

We evaluated blood culture-proven sepsis episodes occurring in microclusters in very-low-birth-weight infants born in the German Neonatal Network (GNN) during 2009-2010. Thirty-seven centers participated in GNN; 23 centers enrolled ≥50 VLBW infants in the study period. Data quality was approved by on-site monitoring. Microclusters of sepsis were defined as occurrence of at least two blood-culture proven sepsis events in different patients of one center within 3 months with the same bacterial species. For microcluster analysis, we selected sepsis episodes with typically cross-transmitted bacteria of high clinical significance including gram-negative rods and Enterococcus spp. In our cohort, 12/2110 (0.6%) infants were documented with an early-onset sepsis and 235 late-onset sepsis episodes (≥72 h of age) occurred in 203/2110 (9.6%) VLBW infants. In 182/235 (77.4%) late-onset sepsis episodes gram-positive bacteria were documented, while coagulase negative staphylococci were found to be the most predominant pathogens (48.5%, 95%CI: 42.01-55.01). Candida spp. and gram-negative bacilli caused 10/235 (4.3%, 95%CI: 1.68% -6.83%) and 43/235 (18.5%) late-onset sepsis episodes, respectively. Eleven microclusters of blood-culture proven sepsis were detected in 7 hospitals involving a total 26 infants. 16/26 cluster patients suffered from Klebsiella spp. sepsis. The median time interval between the first patient's Klebsiella spp. sepsis and cluster cases was 14.1 days (interquartile range: 1-27 days). First patients in the cluster, their linked cases and sporadic sepsis events did not show significant differences in short term outcome parameters. Microclusters of infection are an important phenomenon for late-onset sepsis. Most gram-negative cluster infections occur within 30 days after the first patient was diagnosed and Klebsiella spp. play a major role. It is essential to monitor epidemic microclusters of sepsis in surveillance networks to adapt clinical practice, inform policy and further improve quality of care.

Compliance of clinical microbiology laboratories in the United States with current recommendations for processing respiratory tract specimens from patients with cystic fibrosis.

PubMed

Zhou, Juyan; Garber, Elizabeth; Desai, Manisha; Saiman, Lisa

2006-04-01

Respiratory tract specimens from patients with cystic fibrosis (CF) require unique processing by clinical microbiology laboratories to ensure detection of all potential pathogens. The present study sought to determine the compliance of microbiology laboratories in the United States with recently published recommendations for CF respiratory specimens. Microbiology laboratory protocols from 150 of 190 (79%) CF care sites were reviewed. Most described the use of selective media for Burkholderia cepacia complex (99%), Staphylococcus aureus (82%), and Haemophilus influenzae (89%) and identified the species of all gram-negative bacilli (87%). Only 52% delineated the use of agar diffusion assays for susceptibility testing of Pseudomonas aeruginosa. Standardizing laboratory practices will improve treatment, infection control, and our understanding of the changing epidemiology of CF microbiology.

Childhood vulvovaginitis: report of two cases.

PubMed

Tsai, Hsiu-Yuan; Wan, Chuan; Tseng, Ching-Chang

2006-01-01

Vaginal discharge in young prepubertal girls is a common problem in clinical practice. No specific infective pathogen is identified in most of the children. The reported common microbes include group A beta-hemolytic streptococci, Haemophilus influenzae and some Gram-negative bacilli. Sexually transmitted pathogens such as Neisseria gonorrhoeae and Chlamydia trachomatis are important causes of vulvovaginitis in children suffering from sexual abuse. We report two cases of prepubertal vulvovaginitis presenting with profuse purulent vaginal discharge, and H. influenzae and N. gonorrhoeae identified respectively. Both girls denied any sexual exposure and there was no evidence of sexual abuse. They responded well to antibiotic treatment, and no symptoms recurred in the following months. We would like to emphasize the defined etiology of childhood vulvovaginitis and appropriate treatment, in addition to gynecological evaluation for evidence of sexual abuse.

[A case of liver abscess caused by Fusobacterium nucleatum in a patient with recurrent periodontal diseases].

PubMed

Kim, Yong Hwan; Yoon, Hee Jung; Park, Chan Woong; Kim, Jung Ho; Lee, Min Kyung; Kim, Ki Bang; Na, Dong Jib; Kim, Ji Myung

2011-01-01

Fusobacteria are anaerobic gram-negative, non-spore forming bacilli found in normal flora of the oral cavity, urogenital tract, and gastrointestinal tract. Fusobacterium nucleatum has been seldom reported as a cause of liver abscess, particularly in immunocompetent hosts. A 55-year-old man with frequent periodontal disease visited our hospital with intermittent fever and headache for 2 months. Abdominal CT scan revealed an 8.2 × 6 cm mass in the right hepatic lobe with central low density. Abscess culture revealed F. nucleatum as the causative organism. Percutaneous abscess drainage and intravenous administration of antibiotics for 4 weeks improved symptoms and decreased the abscess size. We report a rare case of liver abscess due to F. nucleatum in an immunocompetent man with periodontal disease.

Post-traumatic infection of the lower limb caused by rare Enterobacteriaceae and Mucorales in a young healthy male.

PubMed

Corti, Giampaolo; Mondanelli, Nicola; Losco, Michele; Bartolini, Laura; Fontanelli, Alessandra; Paradisi, Franco

2009-03-01

Enterobacter amnigenus and Leclercia adecarboxylata are gram-negative aerobic bacilli of the family Enterobacteriaceae that have been isolated from water and, rarely, from various clinical specimens. Absidia is a filamentous fungus of the class Zygomycetes that is ubiquitous in nature and can cause infection, primarily in immunocompromised hosts. Here, we describe an infection of the left lower limb caused by E. amnigenus and L. adecarboxylata with subsequent isolation of Absidia spp. in a patient with multiple traumatic injuries after a major motor vehicle accident. The severity of the clinical picture made amputation necessary, despite aggressive anti-infective therapy with both antibacterial and antifungal agents. Prompt diagnosis and management are mandatory in order to minimize morbidity and even mortality, and reduce the social and economic cost.

[A parotitis as primary infection of Lemierre's syndrome].

PubMed

Valleix, B; Floccard, B; Hautin, E; Faure, F; Allaouchiche, B

2011-09-01

Lemierre's syndrome is a classical presentation of human necrobacillosis. It is characterized by a primary infection in the face including a septic thrombophlebitis of the internal jugular vein and disseminated metastatic abcesses. Fusobacterium necrophorum is the main pathogen found in that syndrome. The diagnosis is based on clinical features, then on the microbiology with positive anaerobic blood cultures as key role and finally on the computed tomography. Most of the time a well-chosen antibiotic treatment against anaerobic pathogens and Gram negative bacilli is efficient but surgery can be useful. We report a case of a 73 years old man, which seems to be unique because it is the first case reported of a Lemierre's syndrome characterized by a parotitis infected by F. necrophorum. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

KPC-4 Is Encoded within a Truncated Tn4401 in an IncL/M Plasmid, pNE1280, Isolated from Enterobacter cloacae and Serratia marcescens

PubMed Central

Bryant, Kendall A.; Van Schooneveld, Trevor C.; Thapa, Ishwor; Bastola, Dhundy; Williams, Laurina O.; Safranek, Thomas J.; Hinrichs, Steven H.; Rupp, Mark E.

2013-01-01

We describe the transfer of blaKPC-4 from Enterobacter cloacae to Serratia marcescens in a single patient. DNA sequencing revealed that KPC-4 was encoded on an IncL/M plasmid, pNE1280, closely related to pCTX-M360. Further analysis found that KPC-4 was encoded within a novel Tn4401 element (Tn4401f) containing a truncated tnpA and lacking tnpR, ISKpn7 left, and Tn4401 IRL-1, which are conserved in other Tn4401 transposons. This study highlights the continued evolution of Tn4401 transposons and movement to multiple plasmid backbones that results in acquisition by multiple species of Gram-negative bacilli. PMID:23070154

Bloodstream infections at a tertiary referral hospital in Yangon, Myanmar.

PubMed

Myat, Tin Ohn; Prasad, Namrata; Thinn, Kyi Kyi; Win, Kyu Kyu; Htike, Wah Win; Zin, Khwar Nyo; Murdoch, David R; Crump, John A

2014-11-01

Data regarding characteristics of bloodstream infections in Myanmar are limited. Blood culture results from all outpatients and inpatients were extracted from records of the Clinical Microbiology Laboratory, Yangon General Hospital, for the period 2005 through 2013. Of 3865 blood cultures performed, 449 (11.6%) were positive for a pathogenic organism. Gram-negative bacteria was the most common organism group, accounting for 246 (55.5%) of 449 isolations. Staphylococcus aureus was the most common isolate, detected in 171 (38.1%) of 449 blood cultures. From 2005-2008 to 2009-2013 the proportion of all pathogenic isolates that were Gram-positive declined from 52.8% (167/316) to 20.3% (27/133) (p<0.001), whereas the proportion of Gram-negative bacteria rose from 45.6% (144/316) to 78.9% (105/133) (p<0.001), with non-fermentative bacilli accounting for much of this increase. Antimicrobial susceptibility testing demonstrated a high prevalence resistance of S. aureus to first-line antimicrobials such as erythromycin, penicillin and oxacillin. More than half of tested Escherichia coli and Citrobacter species showed resistance to amoxicillin-clavulanic acid, ceftriaxone or gentamicin. Bloodstream infections are common among patients receiving blood culture at a tertiary hospital in Yangon, Myanmar. Our findings suggest that antimicrobial resistance among invasive bacteria is common, similar to patterns described elsewhere in the region, and highlight the need for locally adapted antimicrobial guidelines for sepsis management. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Drosophila immunity: analysis of PGRP-SB1 expression, enzymatic activity and function.

PubMed

Zaidman-Rémy, Anna; Poidevin, Mickael; Hervé, Mireille; Welchman, David P; Paredes, Juan C; Fahlander, Carina; Steiner, Hakan; Mengin-Lecreulx, Dominique; Lemaitre, Bruno

2011-02-18

Peptidoglycan is an essential and specific component of the bacterial cell wall and therefore is an ideal recognition signature for the immune system. Peptidoglycan recognition proteins (PGRPs) are conserved from insects to mammals and able to bind PGN (non-catalytic PGRPs) and, in some cases, to efficiently degrade it (catalytic PGRPs). In Drosophila, several non-catalytic PGRPs function as selective peptidoglycan receptors upstream of the Toll and Imd pathways, the two major signalling cascades regulating the systemic production of antimicrobial peptides. Recognition PGRPs specifically activate the Toll pathway in response to Lys-type peptidoglycan found in most Gram-positive bacteria and the Imd pathway in response to DAP-type peptidoglycan encountered in Gram-positive bacilli-type bacteria and in Gram-negative bacteria. Catalytic PGRPs on the other hand can potentially reduce the level of immune activation by scavenging peptidoglycan. In accordance with this, PGRP-LB and PGRP-SC1A/B/2 have been shown to act as negative regulators of the Imd pathway. In this study, we report a biochemical and genetic analysis of PGRP-SB1, a catalytic PGRP. Our data show that PGRP-SB1 is abundantly secreted into the hemolymph following Imd pathway activation in the fat body, and exhibits an enzymatic activity towards DAP-type polymeric peptidoglycan. We have generated a PGRP-SB1/2 null mutant by homologous recombination, but its thorough phenotypic analysis did not reveal any immune function, suggesting a subtle role or redundancy of PGRP-SB1/2 with other molecules. Possible immune functions of PGRP-SB1 are discussed.

Antibiofilm effect of Nocardiopsis sp. GRG 1 (KT235640) compound against biofilm forming Gram negative bacteria on UTIs.

PubMed

Rajivgandhi, Govindan; Vijayan, Ramachandran; Maruthupandy, Muthuchamy; Vaseeharan, Baskaralingam; Manoharan, Natesan

2018-05-01

Urinary tract infections (UTIs) are diverse public health complication and caused by range of pathogens, however mostly Gram negative bacteria cause significant life threatening risks to different populations. The prevalence rate and antimicrobial resistance among the Gram negative uropathogens alarmed significantly heighten the economic burden of these infections. In this study, we investigated the antibiofilm efficiency of Pyrrolo [1,2-a] pyrazine-1,4-dione,hexahydro-3-(2-methylpropyl) extracted from endophytic actinomycetes Nocardiopsis sp. GRG 1 (KT235640) against P. mirabilis and E. coli. The extracted compound was characterized through TLC, HPLC, GC-MS, LC-MS and confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM). The compound, Pyrrolo [1,2-a] pyrazine-1, 4-dione, hexahydro-3-(2-methylpropyl) inhibits both bacterial biofilm formation as well as reduces the viability of preformed biofilms. Furthermore, CLSM image shows cell shrinkage, disorganized cell membrane and loss of viability. The SEM result also confirms the cell wall degradation in treated cells of the bacteria. Hence, the Pyrrolo [1,2-a]pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl) is active against P. mirabilis and E. coli. Copyright © 2018 Elsevier Ltd. All rights reserved.

Performance of a New Rapid Immunoassay Test Kit for Point-of-Care Diagnosis of Significant Bacteriuria

PubMed Central

Cox, Marsha E.; DiNello, Robert K.; Geisberg, Mark; Abbott, April; Roberts, Pacita L.; Hooton, Thomas M.

2015-01-01

Urinary tract infections (UTIs) are frequently encountered in clinical practice and most commonly caused by Escherichia coli and other Gram-negative uropathogens. We tested RapidBac, a rapid immunoassay for bacteriuria developed by Silver Lake Research Corporation (SLRC), compared with standard bacterial culture using 966 clean-catch urine specimens submitted to a clinical microbiology laboratory in an urban academic medical center. RapidBac was performed in accordance with instructions, providing a positive or negative result in 20 min. RapidBac identified as positive 245/285 (sensitivity 86%) samples with significant bacteriuria, defined as the presence of a Gram-negative uropathogen or Staphylococcus saprophyticus at ≥103 CFU/ml. The sensitivities for Gram-negative bacteriuria at ≥104 CFU/ml and ≥105 CFU/ml were 96% and 99%, respectively. The specificity of the test, detecting the absence of significant bacteriuria, was 94%. The sensitivity and specificity of RapidBac were similar on samples from inpatient and outpatient settings, from male and female patients, and across age groups from 18 to 89 years old, although specificity was higher in men (100%) compared with that in women (92%). The RapidBac test for bacteriuria may be effective as an aid in the point-of-care diagnosis of UTIs especially in emergency and primary care settings. PMID:26063858

NBTI 5463 Is a Novel Bacterial Type II Topoisomerase Inhibitor with Activity against Gram-Negative Bacteria and In Vivo Efficacy

PubMed Central

Dougherty, Thomas J.; Nayar, Asha; Newman, Joseph V.; Hopkins, Sussie; Stone, Gregory G.; Johnstone, Michele; Shapiro, Adam B.; Cronin, Mark; Reck, Folkert

2014-01-01

The need for new antibiotics that address serious Gram-negative infections is well recognized. Our efforts with a series of novel bacterial type II topoisomerase inhibitors (NBTIs) led to the discovery of NBTI 5463, an agent with improved activity over other NBTIs against Gram-negative bacteria, in particular against Pseudomonas aeruginosa (F. Reck, D. E. Ehmann, T. J. Dougherty, J. V. Newman, S. Hopkins, G. Stone, N. Agrawal, P. Ciaccio, J. McNulty, H. Barthlow, J. O'Donnell, K. Goteti, J. Breen, J. Comita-Prevoir, M. Cornebise, M. Cronin, C. J. Eyermann, B. Geng, G. R. Carr, L. Pandarinathan, X. Tang, A. Cottone, L. Zhao, N. Bezdenejnih-Snyder, submitted for publication). In the present work, NBTI 5463 demonstrated promising activity against a broad range of Gram-negative pathogens. In contrast to fluoroquinolones, the compound did not form a double-strand DNA cleavable complex with Escherichia coli DNA gyrase and DNA, but it was a potent inhibitor of both DNA gyrase and E. coli topoisomerase IV catalytic activities. In studies with P. aeruginosa, NBTI 5463 was bactericidal. Resistant mutants arose at a low rate, and the mutations were found exclusively in the nfxB gene, a regulator of the MexCD-OprJ efflux system. Levofloxacin-selected resistance mutations in GyrA did not result in decreased susceptibility to NBTI 5463. Animal infection studies demonstrated that NBTI 5463 was efficacious in mouse models of lung, thigh, and ascending urinary tract infections. PMID:24566174

Staphylococcal scalded skin syndrome in a premature newborn caused by methicillin-resistant Staphylococcus aureus: case report.

PubMed

Hörner, Andreas; Hörner, Rosmari; Salla, Adenilde; Nunes, Melise Silveira; Garzon, Litiérri Razia; Rampelotto, Roberta Filipini; Martini, Rosiéli; Santos, Silvana Oliveira dos; Gindri, Lívia; Rodrigues, Mônica de Abreu; Giacomolli, Cláudia

2015-01-01

Staphylococcal scalded skin syndrome is an exfoliative skin disease. Reports of this syndrome in newborns caused by methicillin-resistant Staphylococcus aureus are rare but, when present, rapid diagnosis and treatment is required in order to decrease morbidity and mortality. A premature newly born girl weighing 1,520 g, born with a gestational age of 29 weeks and 4 days, developed staphylococcal scalded skin syndrome on the fifth day of life. Cultures on blood samples collected on the first and fourth days were negative, but Pseudomonas aeruginosa and Enterococcus sp. (vancomycin-sensitive) developed in blood cultures performed on the day of death (seventh day), and Pseudomonas aeruginosa and Serratia marcescens were identified in cultures on nasopharyngeal, buttock and abdominal secretions. In addition to these two Gram-negative bacilli, methicillin-resistant Staphylococcus aureus was isolated in a culture on the umbilical stump (seventh day). The diagnosis of staphylococcal scalded skin syndrome was based on clinical criteria.

Prevalence of communicable disease among restaurant workers along a highway in Assam, India.

PubMed

Biswas, D; Hazarika, N C; Hazarika, D; Mahanta, J

1999-09-01

105 workers of 29 roadside restaurants along a highway in Assam were interviewed for their habits, educational status and were examined for their hygienic status and presence of communicable diseases (STDs,TB etc). Most of them were young, males with 40% literacy; more than half were unmarried. About 30% of them were alcoholic and smokers and 2.9% were addicted to cannabis. The hygienic conditions of the workers were poor. More than one third had sexual contact with multiple sex partners or commercial sex workers and 2% were engaged in homosexual activity. Most of them did not use condom. 25.7% of them had genital lesions suggestive of sexually transmitted disease, 11.8% showed gram negative diplococci in urethral smears and 5.1% were VDRL reactive. Skin infections followed by gastrointestinal disorders and respiratory tract infections were other prevalent problems. 70.6% were positive for intestinal parasites and 22.2% were sputum positive for acid fast bacilli. However all the collected blood samples were negative for HIV.

Characterization of wound infections among patients injured during the 2011 Libyan conflict.

PubMed

Dau, A A; Tloba, S; Daw, M A

2013-04-01

Few studies have analysed the bacterial pathogenesis of infections associated with war-wound in the Eastern Mediterranean region. We analysed surgical wound infections of 1200 patients injured during the Libyan conflict in 2011 and admitted to the emergency services at Tripoli medical centre. Culture swabs or surgical wound debridement samples were collected and cultures were identified and tested for antimicrobial resistance. Of the 1200 patients studied, 498 (42%) were infected with at least 1 pathogen and 57 with >2 pathogens. The most common species were Acinetobacter spp. (isolated from 144 patients), coagulase-negative staphylococci (122), Escherichia coli (107), Pseudomnonas aeruginosa (92) and Klebsiella spp. (86). A high level of resistance to the antibiotics tested was found, especially among Acinetobacter spp. Multi-drug-resistant Gram-negative bacilli were an important complicating factor in wound infections associated with war injuries among injured patients in Libya. Effective policies are needed to control and treat such infections particularly in trauma and emergency services.

Cutaneous anthrax in an unusual location: case report.

PubMed

Sari, Tugba; Koruk, Suda Tekin

2015-12-01

Cutaneous anthrax is well known, unlike anthrax of the lumbar region, which is not reported elsewhere. We present a case of anthrax of the lumbar region in a 50-year-old man. The infection was characterised by a wide, black eschar and oedema on an erythematous ground. After isolation of the Gram-positive bacilli from the skin lesions, prompt antibiotic treatment (intravenous sulbactam-ampicillin 1.5 g every six hours) was initiated. Following eradication of the bacilli after 14 days of antibiotic treatment, a split-thickness skin graft was applied. A diagnosis of anthrax depends on clinical suspicion. Early diagnosis, antibiotic and surgical treatment can facilitate the treatment and prevent development of complications.

Impact of ertapenem on antimicrobial resistance in a sentinel group of Gram-negative bacilli: a 6 year antimicrobial resistance surveillance study.

PubMed

Rodriguez-Osorio, Carlos A; Sanchez-Martinez, Cesar O; Araujo-Melendez, Javier; Criollo, Elia; Macias-Hernandez, Alejandro E; Ponce-de-Leon, Alfredo; Ponce-de-Leon, Sergio; Sifuentes-Osornio, Jose

2015-03-01

To determine the association between ertapenem and resistance of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii-calcoaceticus complex to different antimicrobials while adjusting for relevant hospital factors. This was a retrospective time-series study conducted at a tertiary care centre from September 2002 to August 2008. The specific impact of ertapenem on the resistance of these Gram-negative bacilli (GNB) was assessed by multiple linear regression analysis, adjusting for the average length of stay, rate of hospital-acquired infections and use of 10 other antimicrobials, including type 2 carbapenems. Unadjusted analyses revealed significant increases over the duration of the study in the number of GNB resistant to meropenem/imipenem among 1000 isolates each of E. coli (0.46 ± 0.22, P < 0.05), P. aeruginosa (6.26 ± 2.26, P < 0.05), K. pneumoniae (8.06 ± 1.50, P < 0.0005) and A. baumannii-calcoaceticus complex (25.39 ± 6.81, P < 0.0005). Increased resistance to cefepime (and other extended-spectrum cephalosporins) was observed in E. coli (9.55 ± 1.45, P < 0.0005) and K. pneumoniae (15.21 ± 2.42, P < 0.0005). A. baumannii-calcoaceticus complex showed increased resistance to all antimicrobials except amikacin. After controlling for confounders, ertapenem was not significantly associated (P > 0.05) with changes in resistance for any pathogen/antimicrobial combination. After controlling for confounders, ertapenem was not associated with changes in resistance in a group of sentinel GNB, although significant variations in resistance to different antimicrobials were observed in the unadjusted analyses. These results emphasize the importance of implementation of local resistance surveillance platforms and stewardship programmes to combat the global emergence and spread of antimicrobial resistance. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Alarming emergence, molecular characterization, and outcome of blaNDM-1 in patients infected with multidrug-resistant Gram-negative bacilli in a tertiary care hospital

PubMed Central

Naim, Huma; Rizvi, Meher; Azam, Mohd; Gupta, Richa; Taneja, Neelam; Shukla, Indu; Khan, Haris M.

2017-01-01

INTRODUCTION: This study was conducted to assess the prevalence of metallo-beta-lactamases (MBLs) in general and blaNDM-1 in particular. It also aimed at evaluating clinical characteristics and outcome in patients infected with MBLs. MATERIALS AND METHODS: A total of 116 carbapenem-resistant Gram-negative bacilli (CRGNB) were evaluated in the study. These CRGNB were tested for MBL production both phenotypically for MBLs and genotypically for blaNDM-1 gene by polymerase chain reaction (PCR). Representative stains of NDM-1 isolates were further sequenced by Triyat Scientific Co., (Nagpur, India). RESULTS: Among 116 CRGNB Citrobacter species 28 (24.13%) was the most common pathogen. Phenotypically, MHT, imipenem-EDTA (IPM-EDTA) double-disk synergy test and IPM-EDTA combined disk synergy test (CDST) detected MBL production in 105 (90.51%), 96 (81.03%), and 87 (75%) CRGNB, respectively. However, blaNDM-1 genes were detected in 66 (56.89%) isolates. The prevalence of blaNDM-1 gene was highest among Escherichia coli 26 (100%). Considering PCR as gold standard, it was observed that IMP-EDTA CDST was most specific (78.38%) while MHT was most sensitive (97.47%). Results of blaNDM-1 gene by PCR were further confirmed by sequencing (Triyat genomics, Nagpur). All the 11 representative strains were confirmed to be an NDM-1 gene. The presence of MBLs in our group of patients (non-Intensive Care Unit patients) is a cause for concern. However, on tracing their outcome, it was interesting to note that while the duration of stay lengthened in a large number of patients 112 (96.5%), mortality was relatively low 5 (4.31%). CONCLUSION: The results of this study provide insight into the prevalence of MBLs, including blaNDM-1, in a tertiary care hospital. Antibiotic stewardship implemented in all seriousness may to a great extent stave off the impending pan-drug resistance. The surprising outcome of our patients suggests either that the bacteria trade off virulence for drug resistance or the relatively robust immune response of non ICU patients fights back. PMID:28706386

When it comes to antibiotics, bacteria show some NO-how.

PubMed

Patel, Bhumit A; Crane, Brian R

2010-10-01

Homologs to mammalian nitric oxide synthases are found in many mostly Gram-positive bacteria. In some genera such as bacilli, and staphylococci, these enzymes produce protects against oxidative damage, this effect has now been shown to provide an advantage against antibiotics that kill by increasing cellular levels of reactive oxygen species.

Osteomyelitis associated with Nocardiopsis composta in a dog

PubMed Central

Salas, Elisa N.; Royal, Debra; Kurz, Lance; Loy, J. Dustin

2015-01-01

We report the first detection of Nocardiopsis composta in association with osteomyelitis in a young male miniature Australian shepherd dog. Findings included suppurative osteomyelitis containing intralesional Fite’s acid fast bacilli, aerobic culture of branching Gram-positive rods, and positive identification via phenotypic analysis and 16S rDNA sequencing. PMID:25969577

Resistance surveillance program report for selected European nations (2011).

PubMed

Jones, Ronald N; Flonta, Mirela; Gurler, Nazahat; Cepparulo, Mario; Mendes, Rodrigo E; Castanheira, Mariana

2014-04-01

In the European component of the Regional Resistance Surveillance study for 2011, a total of 21 countries were monitored for antimicrobial resistance patterns including Belgium, Bulgaria (BU), Croatia, Czech Republic, France (F), Germany (GE), Greece (GR), Ireland (IR), Israel (IS), Italy (IT), Poland (PO), Portugal (PT), Romania (RO), Russia (RU), Slovakia (SK), Slovenia, Spain, Sweden (SW), Turkey (T), Ukraine, and United Kingdom. Results from testing 12,572 strains (100 [BU] to 1535 [F] per nation) were interpreted by contemporary published breakpoints. Samples from 47 hospitals were reference tested against agents such as amikacin (AMK), cefoperazone/sulbactam (C/S), colistin (COL), levofloxacin, linezolid (LZD), tigecycline (TIG), vancomycin (VAN), and 21 others. Among Staphylococcus aureus, LZD (MIC90, 2 μg/mL), TIG (MIC90, 0.12 μg/mL), and VAN (MIC90, 1 μg/mL) exhibited complete coverage and methicillin resistance rates among nations (average, 31%) ranged from 0.9% (SW) to 60.0-60.2% (PT, SK). Seven LZD-resistant coagulase-negative staphylococci (only 1.1% resistance overall) were noted in 5 nations, and a Staphylococcus simulans strain (MIC, 8 μg/mL from RO) had L3 mutations (N130D, G152A, F147S, A157R); also 6 LZD-resistant enterococci were detected in 3 countries (GE, IR, T). VAN-resistant enterococci (10% overall; 84% VanA) were found in 14 countries, highest in GE and IR (23.0%). The ESBL phenotype rate for Escherichia coli was 20.1% (range, 0.9% [SW] to 70.0-89.7% [BU, RU]), best inhibited by COL (100.0% S), TIG (100.0%), AMK (83.3-94.1%), C/S (81.0%), and carbapenems (>99.0%; resistant strains in IS and T). Klebsiella spp. had greater ESBL rates (45.7% overall, range 2.5-100.0%), as well as carbapenem resistance (8.3% overall, greatest in BU, GR, IS, IT, PO, RO, RU, T). Non-fermentative Gram-negative bacilli (Pseudomonas aeruginosa, Acinetobacter [ACB]) were generally less susceptible, except against COL (99.2-99.6% S) and TIG (95.0% inhibited at ≤2 μg/mL; ACB only). The following carbapenemases were detected: VIM-1 (2 countries); IMP-1 (1 from T); KPC-2 or -3 (2 countries); VIM-4 (1 from PO), NDM-1 (2 in RO; 2 centers); and OXA-48 or -162 (5 from T; 2 centers). European surveillance sampling demonstrates a wide array of resistant isolates, less prevalent among Gram-positive cocci that remain inhibited by several available agents. However, beta-lactamase-mediated mechanisms have spread widely among Gram-negative bacilli, especially across the Eastern and Southern European nations, severely limiting infection chemotherapy and necessitating escalated antimicrobial stewardship. © 2014.

Surface charge-conversion polymeric nanoparticles for photodynamic treatment of urinary tract bacterial infections

NASA Astrophysics Data System (ADS)

Liu, Shijie; Qiao, Shenglin; Li, Lili; Qi, Guobin; Lin, Yaoxin; Qiao, Zengying; Wang, Hao; Shao, Chen

2015-12-01

Urinary tract infections are typical bacterial infections which result in a number of economic burdens. With increasing antibiotic resistance, it is urgent that new approaches are explored that can eliminate pathogenic bacteria without inducing drug resistance. Antimicrobial photodynamic therapy (PDT) is a new promising tactic. It is a gentle in situ photochemical reaction in which a photosensitizer (PS) generates reactive oxygen species (ROS) under laser irradiation. In this work, we have demonstrated Chlorin e6 (Ce6) encapsulated charge-conversion polymeric nanoparticles (NPs) for efficiently targeting and killing pathogenic bacteria in a weakly acidic urinary tract infection environment. Owing to the surface charge conversion of NPs in an acidic environment, the NPs exhibited enhanced recognition for Gram-positive (ex. S. aureus) and Gram-negative (ex. E. coli) bacteria due to the charge interaction. Also, those NPs showed significant antibacterial efficacy in vitro with low cytotoxicity. The MIC value of NPs to E. coli is 17.91 μg ml-1, compared with the free Ce6 value of 29.85 μg ml-1. Finally, a mouse acute cystitis model was used to assess the photodynamic therapy effects in urinary tract infections. A significant decline (P < 0.05) in bacterial cells between NPs and free Ce6 occurred in urine after photodynamic therapy treatment. And the plated counting results revealed a remarkable bacterial cells drop (P < 0.05) in the sacrificed bladder tissue. Above all, this nanotechnology strategy opens a new door for the treatment of urinary tract infections with minimal side effects.

Surface charge-conversion polymeric nanoparticles for photodynamic treatment of urinary tract bacterial infections.

PubMed

Liu, Shijie; Qiao, Shenglin; Li, Lili; Qi, Guobin; Lin, Yaoxin; Qiao, Zengying; Wang, Hao; Shao, Chen

2015-12-11

Urinary tract infections are typical bacterial infections which result in a number of economic burdens. With increasing antibiotic resistance, it is urgent that new approaches are explored that can eliminate pathogenic bacteria without inducing drug resistance. Antimicrobial photodynamic therapy (PDT) is a new promising tactic. It is a gentle in situ photochemical reaction in which a photosensitizer (PS) generates reactive oxygen species (ROS) under laser irradiation. In this work, we have demonstrated Chlorin e6 (Ce6) encapsulated charge-conversion polymeric nanoparticles (NPs) for efficiently targeting and killing pathogenic bacteria in a weakly acidic urinary tract infection environment. Owing to the surface charge conversion of NPs in an acidic environment, the NPs exhibited enhanced recognition for Gram-positive (ex. S. aureus) and Gram-negative (ex. E. coli) bacteria due to the charge interaction. Also, those NPs showed significant antibacterial efficacy in vitro with low cytotoxicity. The MIC value of NPs to E. coli is 17.91 μg ml(-1), compared with the free Ce6 value of 29.85 μg ml(-1). Finally, a mouse acute cystitis model was used to assess the photodynamic therapy effects in urinary tract infections. A significant decline (P < 0.05) in bacterial cells between NPs and free Ce6 occurred in urine after photodynamic therapy treatment. And the plated counting results revealed a remarkable bacterial cells drop (P < 0.05) in the sacrificed bladder tissue. Above all, this nanotechnology strategy opens a new door for the treatment of urinary tract infections with minimal side effects.

Nosocomial infection in a pediatric intensive care unit in a developing country.

PubMed

Abramczyk, Marcelo L; Carvalho, Werther B; Carvalho, Eduardo S; Medeiros, Eduardo A S

2003-12-01

Determine the rate and outcome of nosocomial infection (NI) in pediatric intensive care unit patients in a developing country. Prospective cohort study using the Centers for Disease Control and Prevention definitions to diagnose nosocomial infection and NNISS (National Nosocomial Infection Surveillance System) methodology. São Paulo Hospital - Universidade Federal de São Paulo - Brazil, a 700-bed teaching hospital with an 8-bed pediatric intensive care unit. All 515 children consecutively admitted to the pediatric intensive care unit from April 1996 to October 1997. The NI incidence was 18.3% and the mean infection rate per 1,000 patient days was 46.1; the ventilator-associated pneumonia rate was 18.7 per 1,000 ventilator days; the central line-associated bloodstream infection rate was 10.2 per 1,000 central line days; and the urinary tract catheter-associated infection rate was 1.8 per 1,000 catheter days. Pneumonia was the most common NI (31.6%), followed by bloodstream infections (17.3%), and surgical site infection (17.3%). Gram-negative bacterias were the most common pathogens identified in the NIs (54.8%), followed by Gram-positive bacterias (23.8%), and yeasts. Pneumonia was the most common type of NI. A high incidence of ventilator-associated pneumonia and central line-associated bloodstream infections was found, whereas the urinary tract catheter-associated infection rate was low. Gram-negative bacterias were the most common etiologic agents identified in the unit, and yeasts were frequently found. Pediatric patients have characteristics of their own, with major differences when compared to the adult population.

Urinary tract infection with Pasteurella multocida in a patient with cat exposure and abnormal urinary tract physiology: Case report and literature review.

PubMed

Costanzo, Joel T; Wojciechowski, Amy L; Bajwa, Rajinder P S

2017-01-01

Pasteurella multocida is a gram-negative organism that commonly colonizes the mouth of cats and dogs, and is known to cause infection in humans associated with animal bites or scratches. Sites of infection other than skin and soft tissue are rare, but have been reported in patients with specific risk factors including anatomical abnormalities or immunosuppression. Herein, we report a case of a symptomatic urinary tract infection caused by P. multocida in a 59 year old female who presented to the hospital with complaints of systemic symptoms including malaise, rigors, and chills, as well as thick, malodorous urine. The patient self-catheterized multiple times daily due to urostomy with Kock pouch. Treatment with piperacillin/tazobactam followed by amoxicillin resulted in resolution of the infection.

Relative Frequency, Characteristics, and Antimicrobial Susceptibility Patterns of Vibrio spp., Aeromonas spp., Chromobacterium violaceum, and Shewanella spp. in the Northern Territory of Australia, 2000–2013

PubMed Central

McAuliffe, Gary N.; Hennessy, Jann; Baird, Robert W.

2015-01-01

Vibrio, Aeromonas, Chromobacterium violaceum, and Shewanella (VACS) are water-associated Gram-negative organisms that can cause a variety of infections. The frequency, patient characteristics, and antimicrobial susceptibilities for 468 isolates from 442 patients from the Northern Territory were reviewed. Aeromonas spp. (312 of 468; 67%) were most commonly isolated followed by Vibrio spp. (71 of 468; 15%), Shewanella spp. (61 of 468; 13%), and C. violaceum (24 of 468; 5%). A strong male predominance was found (male to female ratio of 2.3:1). Skin and soft tissue isolations (373 of 468; 80%) from lower limb infections (222 of 371; 60%) were the most common clinical manifestation. The episodes were usually polymicrobial (281 of 468; 60%). Coisolates included Staphylococcus aureus (137 of 468; 29%), β-hemolytic streptococci (74 of 468; 16%), enterobacteriaceae (111 of 468; 24%), non-fermentative Gram-negative bacilli (35 of 468; 7%), and other VACS organisms (37 of 468; 8%). Antimicrobial resistance of VACS organisms to ciprofloxacin (0–4%), cefepime (0–3%), and gentamicin (0–0.8%) and Vibrio spp., Aeromonas spp., and Shewanella to cotrimoxazole (0–3%) was rarely shown. For water-associated lower limb skin and soft tissue infections in the tropics, clinicians should consider empirical antimicrobial therapy with agents active against S. aureus and VACS organisms. PMID:25548380

Type 1 fimbrial expression enhances Escherichia coli virulence for the urinary tract.

PubMed

Connell, I; Agace, W; Klemm, P; Schembri, M; Mărild, S; Svanborg, C

1996-09-03

Type 1 fimbriae are adhesion organelles expressed by many Gram-negative bacteria. They facilitate adherence to mucosal surfaces and inflammatory cells in vitro, but their contribution to virulence has not been defined. This study presents evidence that type 1 fimbriae increase the virulence of Escherichia coli for the urinary tract by promoting bacterial persistence and enhancing the inflammatory response to infection. In a clinical study, we observed that disease severity was greater in children infected with E. coli O1:K1:H7 isolates expressing type 1 fimbriae than in those infected with type 1 negative isolates of the same serotype. The E. coli O1:K1:H7 isolates had the same electrophoretic type, were hemolysin-negative, expressed P fimbriae, and carried the fim DNA sequences. When tested in a mouse urinary tract infection model, the type 1-positive E. coli O1:K1:H7 isolates survived in higher numbers, and induced a greater neutrophil influx into the urine, than O1:K1:H7 type 1-negative isolates. To confirm a role of type 1 fimbriae, a fimH null mutant (CN1016) was constructed from an O1:K1:H7 type 1-positive parent. E. coli CN1016 had reduced survival and inflammatogenicity in the mouse urinary tract infection model. E. coli CN1016 reconstituted with type 1 fimbriae (E. coli CN1018) had restored virulence similar to that of the wild-type parent strain. These results show that type 1 fimbriae in the genetic background of a uropathogenic strain contribute to the pathogenesis of E. coli in the urinary tract.

Risk factors for infection with multidrug-resistant bacteria in non-ventilated patients with hospital-acquired pneumonia.

PubMed

Seligman, Renato; Ramos-Lima, Luis Francisco; Oliveira, Vivian do Amaral; Sanvicente, Carina; Sartori, Juliana; Pacheco, Elyara Fiorin

2013-01-01

To identify risk factors for the development of hospital-acquired pneumonia (HAP) caused by multidrug-resistant (MDR) bacteria in non-ventilated patients. This was a retrospective observational cohort study conducted over a three-year period at a tertiary-care teaching hospital. We included only non-ventilated patients diagnosed with HAP and presenting with positive bacterial cultures. Categorical variables were compared with chi-square test. Logistic regression analysis was used to determine risk factors for HAP caused by MDR bacteria. Of the 140 patients diagnosed with HAP, 59 (42.1%) were infected with MDR strains. Among the patients infected with methicillin-resistant Staphylococcus aureus and those infected with methicillin-susceptible S. aureus, mortality was 45.9% and 50.0%, respectively (p = 0.763). Among the patients infected with MDR and those infected with non-MDR gram-negative bacilli, mortality was 45.8% and 38.3%, respectively (p = 0.527). Univariate analysis identified the following risk factors for infection with MDR bacteria: COPD; congestive heart failure; chronic renal failure; dialysis; urinary catheterization; extrapulmonary infection; and use of antimicrobial therapy within the last 10 days before the diagnosis of HAP. Multivariate analysis showed that the use of antibiotics within the last 10 days before the diagnosis of HAP was the only independent predictor of infection with MDR bacteria (OR = 3.45; 95% CI: 1.56-7.61; p = 0.002). In this single-center study, the use of broad-spectrum antibiotics within the last 10 days before the diagnosis of HAP was the only independent predictor of infection with MDR bacteria in non-ventilated patients with HAP.

Risk factors for infection with multidrug-resistant bacteria in non-ventilated patients with hospital-acquired pneumonia*,**

PubMed Central

Seligman, Renato; Ramos-Lima, Luis Francisco; Oliveira, Vivian do Amaral; Sanvicente, Carina; Sartori, Juliana; Pacheco, Elyara Fiorin

2013-01-01

OBJECTIVE: To identify risk factors for the development of hospital-acquired pneumonia (HAP) caused by multidrug-resistant (MDR) bacteria in non-ventilated patients. METHODS: This was a retrospective observational cohort study conducted over a three-year period at a tertiary-care teaching hospital. We included only non-ventilated patients diagnosed with HAP and presenting with positive bacterial cultures. Categorical variables were compared with chi-square test. Logistic regression analysis was used to determine risk factors for HAP caused by MDR bacteria. RESULTS: Of the 140 patients diagnosed with HAP, 59 (42.1%) were infected with MDR strains. Among the patients infected with methicillin-resistant Staphylococcus aureus and those infected with methicillin-susceptible S. aureus, mortality was 45.9% and 50.0%, respectively (p = 0.763). Among the patients infected with MDR and those infected with non-MDR gram-negative bacilli, mortality was 45.8% and 38.3%, respectively (p = 0.527). Univariate analysis identified the following risk factors for infection with MDR bacteria: COPD; congestive heart failure; chronic renal failure; dialysis; urinary catheterization; extrapulmonary infection; and use of antimicrobial therapy within the last 10 days before the diagnosis of HAP. Multivariate analysis showed that the use of antibiotics within the last 10 days before the diagnosis of HAP was the only independent predictor of infection with MDR bacteria (OR = 3.45; 95% CI: 1.56-7.61; p = 0.002). CONCLUSIONS: In this single-center study, the use of broad-spectrum antibiotics within the last 10 days before the diagnosis of HAP was the only independent predictor of infection with MDR bacteria in non-ventilated patients with HAP. PMID:23857697

[Increasing incidence of community-acquired pneumonia caused by atypical microorganisms].

PubMed

Tazón-Varela, M A; Alonso-Valle, H; Muñoz-Cacho, P; Gallo-Terán, J; Piris-García, X; Pérez-Mier, L A

2017-09-01

Knowing the most common microorganisms in our environment can help us to make proper empirical treatment decisions. The aim is to identify those microorganisms causing community-acquired pneumonia. An observational, descriptive and prospective study was conducted, including patients over 14 years with a clinical and radiographic diagnosis of community-acquired pneumonia during a 383 consecutive day period. A record was made of sociodemographic variables, personal history, prognostic severity scales, progress, and pathogenic agents. The aetiological diagnosis was made using blood cultures, detection of Streptococcus pneumoniae and Legionella pneumophila urinary antigens, sputum culture, influenza virus and Streptococcus pyogenes detection. Categorical variables are presented as absolute values and percentages, and continuous variables as their means and standard deviations. Of the 287 patients included in the study (42% women, mean age 66±22 years), 10.45% died and 70% required hospital admission. An aetiological diagnosis was achieved in 43 patients (14.98%), with 16 microorganisms found in 59 positive samples. The most frequently isolated pathogen was Streptococcus pneumonia (24/59, 41%), followed by gram-negative enteric bacilli, Klebsiella pneumonia, Escherichia coli, Serratia marcescens and Enterobacter cloacae isolated in 20% of the samples (12/59), influenza virus (5/59, 9%), methicillin-resistant Staphylococcus aureus (3/59, 5%), Pseudomonas aeruginosa (2/59, 3%), Moraxella catarrhalis (2/59, 3%), Legionella pneumophila (2/59, 3%), and Haemophilus influenza (2/59, 3%). Polymicrobial infections accounted for 14% (8/59). A high percentage of atypical microorganisms causing community-acquired pneumonia were found. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

E. coli Multiresistant Meningitis after Transrectal Prostate Biopsy

PubMed Central

Alecsandru, Diana; Gestoso, Israel; Romero, Ana; Martinez, Alfonso; García, Ana; Lobo, Julio; Yagüe, M. Ruiz

2006-01-01

Escherichia coli meningitis is a frequent pathology in children younger than 3 years old, but is an uncommon disease in adults. E. coli infection is the main cause of intrahospital bacteremia as a consequence of the employment of different medical procedures. Our patient, male, 69 years old, presented with fever, progressive difficulty in breathing, and shivers 24 h after transrectal prostate biopsy, with an absence of any other symptoms. He received prophylactic treatment with ciprofloxacin and later empirical treatment with ampicillin and tobramicin. After that, the patient presented with fever, headache, behavioral changes, somnolence, disorientation, a fluctuating level of conscience, cutaneous widespread pallor, and acute urinary retention. On physical exploration, we observed generalized hypoventilation, Glasgow 10, stiffness of the neck, inconclusive Kernig; the remaining neurological exploration was normal. Systematic of blood: leukocytes = 8,510/mm3 (94.5% polymorphonuclear), platelet = 87,000/mm3, pH = 7.51, pCO2 = 28.8 mmHg, pO2 = 61 mmHg, O2 saturation = 93.8%, and remaining values were normal. Chest X- ray, cranial CT scan, urine cultures were normal. Blood culture: E. coli. CSF: glucose <0.4 g/l, total proteins = 3.05 g/l, PMN = 7 cells. Microscopic examination of the CSF: Gram-negative bacilli; CSF's culture: abundant E. coli. The case of acute meningitis by multiresistant E. coli after transrectal prostate biopsy presented demonstrates that antibiotic prevention with ciprofloxacin is not absolutely risk free. Besides the use of antibiotic prevention for multiresistant microorganisms, the urologist and other physicians involved in the procedure must not forget that the rate of major complications of transrectal prostate biopsy is 1%, especially when it is performed in patients who will not benefit from that biopsy. PMID:17619698

Prevotella histicola sp. nov., isolated from the human oral cavity.

PubMed

Downes, Julia; Hooper, Samuel J; Wilson, Melanie J; Wade, William G

2008-08-01

Three strains of anaerobic, variably pigmenting, Gram-negative bacilli isolated from human oral mucosal tissue were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis and DNA-DNA hybridization revealed that the strains constituted a novel group within the genus Prevotella, being most closely related to Prevotella melaninogenica and Prevotella veroralis. A novel species, Prevotella histicola sp. nov., is proposed to accommodate these strains. Prevotella histicola is saccharolytic and produces acetic acid and succinic acid as major end products of fermentation and trace to minor amounts of isovaleric acid and lactic acid. The G+C content of the DNA of the type strain is 43 mol%. The type strain of Prevotella histicola is T05-04T (=DSM 19854T=CCUG 55407T).

Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression.

PubMed

Mars, Ruben A T; Nicolas, Pierre; Denham, Emma L; van Dijl, Jan Maarten

2016-12-01

Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5' untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5' ends of mRNA molecules. These can include 5' secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression

PubMed Central

Mars, Ruben A. T.; Nicolas, Pierre; Denham, Emma L.

2016-01-01

SUMMARY Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5′ untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5′ ends of mRNA molecules. These can include 5′ secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis. PMID:27784798

Changes in the Microflora of Haddock Fillets and Shucked Soft-Shelled Clams After Irradiation with Co60 Gamma Rays and Storage at 0 C and 6 C

PubMed Central

Masurovsky, E. B.; Voss, J. S.; Goldblith, S. A.

1963-01-01

Frequency distribution patterns of aerobic-facultative microflora, obtained by random selection of macrocolonies from samples of haddock fillets and shucked soft-shelled clams before and after treatment with doses of from 50,000 to 800,000 rad of Co60 gamma rays, are presented, with analyses and interpretation. The data showed that a decided change occurred in the constitution of the microbial populations of both products: from a mixed gram-negative—gram-positive flora to a predominantly gram-positive flora immediately after irradiation. The great majority of these surviving microorganisms were micrococci, sporeforming bacilli, and certain yeasts, molds, and actinomyces. During storage at refrigeration temperatures above freezing, the microflora changed from the descendants of the more radioresistant gram-positive species to the more prolific gram-negative psychrophilic species that flourish at these low temperatures. Micrococci and gram-positive rods declined somewhat during the rise of the actively proteolytic-lipolytic pseudomonads and related species, but still remained at high enough levels to contribute significantly to the spoilage observed at different times in storage. The eventual spoilage of haddock fillets was characterized by discoloration of the cream-white tissue with water-soluble yellow, green, and red bacterial pigments; degradation of the tissue, by proteolytic and other microbial enzymes, to a watery, flaccid mass; and formation of volatile compounds that smelled putrid, rancid, and generally foul and pungent. Shucked soft-shelled clams displayed a different spoilage pattern, changing to a variegated brown-gray and forming a matted or loose gelatinous mass from which arose stale, acrid, putrid, sulfurous odors. These differences are believed to be attributable to the varied biochemical nature of the tissues involved, the Eh potential within the tissues, the time sequence of microfloral change, and the species and types of microorganisms associated with each product. Staphylococci were present in small numbers in some of the samples tested, but did not appear to be species of public health significance. Gram-negative enteric rods were also encountered, but were considered to be of doubtful public health importance. More detailed investigations, designed to study the effects of Co60 gamma radiations on such microbes in sea foods, would be useful in assessing the problem further. PMID:13933509

Gram-positive, motile, cluster-forming cocci as a cause of urinary infection

PubMed Central

Virtanen, S.

1974-01-01

One hundred and thirteen strains of motile, Gram-positive, catalase-positive, cluster-forming cocci were isolated from patients with urinary infection attending a private surgery. They constituted 1% of the total 11 302 positive cultures. The biochemical characteristics and the drug sensitivities of the strains are described. The significance of motility for organisms which cause urinary infections is pointed out. At the present time the organisms isolated are orphans in the controversial classification of staphylococci and micrococci. Images PMID:4852184

Urine Stasis Predisposes to Urinary Tract Infection by an Opportunistic Uropathogen in the Megabladder (Mgb) Mouse.

PubMed

Becknell, Brian; Mohamed, Ahmad Z; Li, Birong; Wilhide, Michael E; Ingraham, Susan E

2015-01-01

Urinary stasis is a risk factor for recurrent urinary tract infection (UTI). Homozygous mutant Megabladder (Mgb-/-) mice exhibit incomplete bladder emptying as a consequence of congenital detrusor aplasia. We hypothesize that this predisposes Mgb-/- mice to spontaneous and experimental UTI. Mgb-/-, Mgb+/-, and wild-type female mice underwent serial ultrasound and urine cultures at 4, 6, and 8 weeks to detect spontaneous UTI. Urine bacterial isolates were analyzed by Gram stain and speciated. Bladder stones were analyzed by x-ray diffractometry. Bladders and kidneys were subject to histologic analysis. The pathogenicity of coagulase-negative Staphylococcus (CONS) isolated from Mgb-/- urine was tested by transurethral administration to culture-negative Mgb-/- or wild-type animals. The contribution of urinary stasis to CONS susceptibility was evaluated by cutaneous vesicostomy in Mgb-/- mice. Mgb-/- mice develop spontaneous bacteriuria (42%) and struvite bladder stones (31%) by 8 weeks, findings absent in Mgb+/- and wild-type controls. CONS was cultured as a solitary isolate from Mgb-/- bladder stones. Bladders and kidneys from mice with struvite stones exhibit mucosal injury, inflammation, and fibrosis. These pathologic features of cystitis and pyelonephritis are replicated by transurethral inoculation of CONS in culture-negative Mgb-/- females, whereas wild-type animals are less susceptible to CONS colonization and organ injury. Cutaneous vesicostomy prior to CONS inoculation significantly reduces the quantity of CONS recovered from Mgb-/- urine, bladders, and kidneys. CONS is an opportunistic uropathogen in the setting of urinary stasis, leading to enhanced UTI incidence and severity in Mgb-/- mice.

Urine Stasis Predisposes to Urinary Tract Infection by an Opportunistic Uropathogen in the Megabladder (Mgb) Mouse

PubMed Central

Becknell, Brian; Mohamed, Ahmad Z.; Li, Birong; Wilhide, Michael E.; Ingraham, Susan E.

2015-01-01

Purpose Urinary stasis is a risk factor for recurrent urinary tract infection (UTI). Homozygous mutant Megabladder (Mgb-/-) mice exhibit incomplete bladder emptying as a consequence of congenital detrusor aplasia. We hypothesize that this predisposes Mgb-/- mice to spontaneous and experimental UTI. Methods Mgb-/-, Mgb+/-, and wild-type female mice underwent serial ultrasound and urine cultures at 4, 6, and 8 weeks to detect spontaneous UTI. Urine bacterial isolates were analyzed by Gram stain and speciated. Bladder stones were analyzed by x-ray diffractometry. Bladders and kidneys were subject to histologic analysis. The pathogenicity of coagulase-negative Staphylococcus (CONS) isolated from Mgb-/- urine was tested by transurethral administration to culture-negative Mgb-/- or wild-type animals. The contribution of urinary stasis to CONS susceptibility was evaluated by cutaneous vesicostomy in Mgb-/- mice. Results Mgb-/- mice develop spontaneous bacteriuria (42%) and struvite bladder stones (31%) by 8 weeks, findings absent in Mgb+/- and wild-type controls. CONS was cultured as a solitary isolate from Mgb-/- bladder stones. Bladders and kidneys from mice with struvite stones exhibit mucosal injury, inflammation, and fibrosis. These pathologic features of cystitis and pyelonephritis are replicated by transurethral inoculation of CONS in culture-negative Mgb-/- females, whereas wild-type animals are less susceptible to CONS colonization and organ injury. Cutaneous vesicostomy prior to CONS inoculation significantly reduces the quantity of CONS recovered from Mgb-/- urine, bladders, and kidneys. Conclusions CONS is an opportunistic uropathogen in the setting of urinary stasis, leading to enhanced UTI incidence and severity in Mgb-/- mice. PMID:26401845

Proteus mirabilis and Urinary Tract Infections

PubMed Central

Schaffer, Jessica N.; Pearson, Melanie M.

2015-01-01

Proteus mirabilis is a Gram-negative bacterium which is well-known for its ability to robustly swarm across surfaces in a striking bulls’-eye pattern. Clinically, this organism is most frequently a pathogen of the urinary tract, particularly in patients undergoing long-term catheterization. This review covers P. mirabilis with a focus on urinary tract infections (UTI), including disease models, vaccine development efforts, and clinical perspectives. Flagella-mediated motility, both swimming and swarming, is a central facet of this organism. The regulation of this complex process and its contribution to virulence is discussed, along with the type VI-secretion system-dependent intra-strain competition which occurs during swarming. P. mirabilis uses a diverse set of virulence factors to access and colonize the host urinary tract, including urease and stone formation, fimbriae and other adhesins, iron and zinc acquisition, proteases and toxins, biofilm formation, and regulation of pathogenesis. While significant advances in this field have been made, challenges remain to combatting complicated UTI and deciphering P. mirabilis pathogenesis. PMID:26542036

Proteus mirabilis and Urinary Tract Infections.

PubMed

Schaffer, Jessica N; Pearson, Melanie M

2015-10-01

Proteus mirabilis is a Gram-negative bacterium and is well known for its ability to robustly swarm across surfaces in a striking bulls'-eye pattern. Clinically, this organism is most frequently a pathogen of the urinary tract, particularly in patients undergoing long-term catheterization. This review covers P. mirabilis with a focus on urinary tract infections (UTI), including disease models, vaccine development efforts, and clinical perspectives. Flagella-mediated motility, both swimming and swarming, is a central facet of this organism. The regulation of this complex process and its contribution to virulence is discussed, along with the type VI-secretion system-dependent intra-strain competition, which occurs during swarming. P. mirabilis uses a diverse set of virulence factors to access and colonize the host urinary tract, including urease and stone formation, fimbriae and other adhesins, iron and zinc acquisition, proteases and toxins, biofilm formation, and regulation of pathogenesis. While significant advances in this field have been made, challenges remain to combatting complicated UTI and deciphering P. mirabilis pathogenesis.

Ready for a world without antibiotics? The Pensières Antibiotic Resistance Call to Action

PubMed Central

2012-01-01

Resistance to antibiotics has increased dramatically over the past few years and has now reached a level that places future patients in real danger. Microorganisms such as Escherichia coli and Klebsiella pneumoniae, which are commensals and pathogens for humans and animals, have become increasingly resistant to third-generation cephalosporins. Moreover, in certain countries, they are also resistant to carbapenems and therefore susceptible only to tigecycline and colistin. Resistance is primarily attributed to the production of beta-lactamase genes located on mobile genetic elements, which facilitate their transfer between different species. In some rare cases, Gram-negative rods are resistant to virtually all known antibiotics. The causes are numerous, but the role of the overuse of antibiotics in both humans and animals is essential, as well as the transmission of these bacteria in both the hospital and the community, notably via the food chain, contaminated hands, and between animals and humans. In addition, there are very few new antibiotics in the pipeline, particularly for Gram-negative bacilli. The situation is slightly better for Gram-positive cocci as some potent and novel antibiotics have been made available in recent years. A strong and coordinated international programme is urgently needed. To meet this challenge, 70 internationally recognized experts met for a two-day meeting in June 2011 in Annecy (France) and endorsed a global call to action ("The Pensières Antibiotic Resistance Call to Action"). Bundles of measures that must be implemented simultaneously and worldwide are presented in this document. In particular, antibiotics, which represent a treasure for humanity, must be protected and considered as a special class of drugs. PMID:22958833

Diversity of Innate Immune Recognition Mechanism for Bacterial Polymeric meso-Diaminopimelic Acid-type Peptidoglycan in Insects

PubMed Central

Yu, Yang; Park, Ji-Won; Kwon, Hyun-Mi; Hwang, Hyun-Ok; Jang, In-Hwan; Masuda, Akiko; Kurokawa, Kenji; Nakayama, Hiroshi; Lee, Won-Jae; Dohmae, Naoshi; Zhang, Jinghai; Lee, Bok Luel

2010-01-01

In Drosophila, the synthesis of antimicrobial peptides in response to microbial infections is under the control of the Toll and immune deficiency (Imd) signaling pathway. The Toll signaling pathway responds mainly to the lysine-type peptidoglycan of Gram-positive bacteria and fungal β-1,3-glucan, whereas the Imd pathway responds to the meso-diaminopimelic acid (DAP)-type peptidoglycan of Gram-negative bacteria and certain Gram-positive bacilli. Recently we determined the activation mechanism of a Toll signaling pathway biochemically using a large beetle, Tenebrio molitor. However, DAP-type peptidoglycan recognition mechanism and its signaling pathway are still unclear in the fly and beetle. Here, we show that polymeric DAP-type peptidoglycan, but not its monomeric form, formed a complex with Tenebrio peptidoglycan recognition protein-SA, and this complex activated the three-step proteolytic cascade to produce processed Spätzle, a Toll receptor ligand, and induced Drosophila defensin-like antimicrobial peptide in Tenebrio larvae similarly to polymeric lysine-type peptidoglycan. Monomeric DAP-type peptidoglycan induced Drosophila diptericin-like antimicrobial peptide in Tenebrio hemocytes. In addition, both polymeric and monomeric DAP-type peptidoglycans induced expression of Tenebrio peptidoglycan recognition protein-SC2, which is DAP-type peptidoglycan-selective N-acetylmuramyl-l-alanine amidase that functions as a DAP-type peptidoglycan scavenger, appearing to function as a negative regulator of the DAP-type peptidoglycan signaling by cleaving DAP-type peptidoglycan in Tenebrio larvae. Taken together, these results demonstrate that molecular recognition mechanism for polymeric DAP-type peptidoglycan is different between Tenebrio larvae and Drosophila adults, providing biochemical evidences of biological diversity of innate immune responses in insects. PMID:20702416

Urinary Tract Infections Among Hospitalized Adults in the Early Post-Liver Transplant Period: Prevalence, Risk Factors, Causative Agents, and Microbial Susceptibility.

PubMed

Pouladfar, Gholamreza; Jafarpour, Zahra; Firoozifar, Mohammad; Malek Hosseini, Seyed Ali; Rasekh, Razieh; Khosravifard, Leila; Janghorban, Parisa

2017-02-01

Urinary tract infections are among the most common infections after liver transplant, especially soon after surgery. This study analyzed urinary tract infections or bacteriuria, their causative agents, and related risk factors in the early period after liver transplant in hospitalized adult transplant recipients in the main liver transplant referral center in Iran. In this prospective study, 389 consecutive adult patients who underwent liver transplant at the Nemazee Teaching Hospital were enrolled between October 2014 and October 2015. Risk factors were compared for patients who developed urinary tract infections or bacteriuria ("infection group "; n = 63 [16.2% ]) and patients without evidence of infection ("control group "; n = 211 [54.2% ]). Patients with sites of infection other than the urinary tract were excluded. Antimicrobial sus ceptibility testing was performed using the Kirby-Bauer disk-diffusion method. Univariate and multivariate analyses compared variables between the 2 groups. Seventy-nine episodes of urinary tract infections or bacteriuria occurred in the infection group. Multiple logistic regression analysis showed that female sex, hospitalization 2 to 7 days before transplant, and frequency of abdominal exploration were 11.0, 5.9, and 3.0 times more common in the infection group than in the control group. The chance of infection rises 1.1 times with each one unit increase of body mass index. The most common infection causes were gram-negative bacteria (n = 50; 63.3%), predominantly Escherichia coli (n = 24; 30.4%); followed by gram-positive bacteria (n = 20; 25.3%), predominantly Enterococcus species (n = 14; 17.8%) that had a high incidence of vancomycin resistance (n = 10; 71.4%); and non-Candida albicans species isolates (n = 9; 11.4%). Urinary tract infections are a common infection in hospitalized adult patients soon after liver transplant. Female sex, hospitalization shortly before transplant, more frequent abdominal exploration, and higher body mass index substantially increased the risk of developing such infections in this period.

DIFFERENCES IN CULTURAL YIELD OF MYCOBACTERIUM TUBERCULOSIS ON MEDIA PREPARED USING COMMERCIAL AND HOUSEHOLD EGGS.

PubMed

Noori, Muhammad Yahya; AJi, Zaheer; Khan, Ghazala; Sharafat, Shaheen; Masroor, Muhammad

2015-01-01

Mycobacterial culture is considered as the gold standard for TB diagnosis. It is performed on egg-based media using commercially available eggs to grow Mycobacteria from clinical samples. These eggs are known to contain high concentration of antibiotics, including fluoroquinolones, given to chicken to prevent early mortality. This study was performed to compare Mycobacterial growth on media prepared from commercial and antibiotic free household eggs. Sputum samples from negative (No bacilli in 100 oil immersion field), scanty (1-9 AFB in 100 fields), 1+ (10-99 bacilli per field), 2+ (1-10 bacilli per field) and 3+ (>10 bacilli per field) were inoculated dually on Ogawa medium prepared from commercial and household eggs. Tubes were inspected every fourth day for the appearance of colonies till 60 days. Data tabulations and statistical analysis (F test for variation and unpaired Student's t test) were performed on Microsoft Excel. One microscopically negative sample showed growth on media prepared from household eggs, while all were negative on that prepared from commercial eggs. There were significant differences in time to culture positivity for samples graded 1+ (p = 0.02), 2+ (p = 0.002) and 3+ (p = 0.0003). Commercial eggs containing antibiotics can be a source of false negativity in cultures especially in microscopically negative samples. This can be of special concern in HIV patients who have high smear negativity. It is therefore important to either develop provision of antibiotic free eggs for media preparation or to develop and validate other laboratory investigations for smear negative TB patients.

Introduction of sample tubes with sodium azide as a preservative for ethyl glucuronide in urine.

PubMed

Luginbühl, Marc; Weinmann, Wolfgang; Al-Ahmad, Ali

2017-09-01

Ethyl glucuronide (EtG) is a direct alcohol marker, which is widely used for clinical and forensic applications, mainly for abstinence control. However, the instability of EtG in urine against bacterial degradation or the post-collectional synthesis of EtG in contaminated samples may cause false interpretation of EtG results in urine samples. This study evaluates the potential of sodium azide in tubes used for urine collection to hinder degradation of ethyl glucuronide by bacterial metabolism taking place during growth of bacterial colonies. The tubes are part of a commercial oral fluid collection device. The sampling system was tested with different gram-positive and gram-negative bacterial species previously observed in urinary tract infections, such as Escherichia coli, Staphylococcus aureus, Enterecoccus faecalis, Staphylococcus epidermidis, Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomonas aeruginosa. Inhibition of bacterial growth by sodium azide, resulting in lower numbers of colony forming units compared to control samples, was observed for all tested bacterial species. To test the prevention of EtG degradation by the predominant pathogen in urinary tract infection, sterile-filtered urine and deficient medium were spiked with EtG, and inoculated with E. coli prior to incubation for 4 days at 37 °C in tubes with and without sodium azide. Samples were collected every 24 hours, during four consecutive days, whereby the colony forming units (CFU) were counted on Columbia blood agar plates, and EtG was analyzed by LC-MS/MS. As expected, EtG degradation was observed when standard polypropylene tubes were used for the storage of contaminated samples. However, urine specimens collected in sodium azide tubes showed no or very limited bacterial growth and no EtG degradation. As a conclusion, sodium azide is useful to reduce bacterial growth of gram-negative and gram-positive bacteria. It inhibits the degradation of EtG by E. coli and can be used for the stabilization of EtG in urine samples.

Comparison of flomoxef with latamoxef in the treatment of sepsis and/or Gram-negative bacteremia in adult patients.

PubMed

Chen, Y C; Hung, C C; Lin, S F; Chang, S C; Hsieh, W C

1996-05-01

The safety and efficacy of flomoxef and latamoxef were compared in the treatment of hospitalized patients with sepsis and/or Gram-negative bacteremia in a prospective, open-labelled clinical trial. Patients were randomized to receive 1 to 2 g intravenous doses of either flomoxef every 6 to 12 h, or latamoxef every 8 to 12 h. Data from 21 patients given flomoxef and 23 patients given latamoxef were included in the evaluation of efficacy. Flomoxef produced clinical cure and satisfactory microbiological responses in 85.7% and 100% of patients, respectively. These results were similar to those obtained with latamoxef (87% and 100%, respectively). In addition, no significant difference was found in mean age, sex, severity of infection, distribution of pathogens and focus of infection between the two groups. However, the flomoxef group included more patients with ultimately fatal diseases. Six patients given flomoxef and two patients given latamoxef developed superinfections caused by yeast, enterococci and Pseudomonas aeruginosa in the urinary tract. Mild and reversible adverse reactions probably related to flomoxef and latamoxef were noted in 14.3% and 13% of patients, respectively. The results of this study demonstrated that flomoxef is a safe and effective antimicrobial agent in the treatment of patients with sepsis and/or Gram-negative bacteremia.

Evaluation of the MicroScan ESBL plus confirmation panel for detection of extended-spectrum beta-lactamases in clinical isolates of oxyimino-cephalosporin-resistant Gram-negative bacteria.

PubMed

Stürenburg, Enno; Lang, Melanie; Horstkotte, Matthias A; Laufs, Rainer; Mack, Dietrich

2004-11-01

We aimed to assess the performance of the MicroScan ESBL plus confirmation panel using a series of 87 oxyimino-cephalosporin-resistant Gram-negative bacilli of various species. Organisms tested included 57 extended-spectrum beta-lactamase (ESBL) strains comprising Enterobacter aerogenes (3), Enterobacter cloacae (10), Escherichia coli (11), Klebsiella pneumoniae (26), Klebsiella oxytoca (3) and Proteus mirabilis (4). Also included were 30 strains resistant to oxyimino cephalosporins but lacking ESBLs, which were characterized with other resistance mechanisms, such as inherent clavulanate susceptibility in Acinetobacter spp. (4), hyperproduction of AmpC enzyme in Citrobacter freundii (2), E. aerogenes (3), E. cloacae (3), E. coli (4), Hafnia alvei (1) and Morganella morganii (1), production of plasmid-mediated AmpC beta-lactamase in K. pneumoniae (3) and E. coli (3) or hyperproduction of K1 enzyme in K. oxytoca (6). The MicroScan MIC-based clavulanate synergy correctly classified 50 of 57 ESBL strains as ESBL-positive and 23 of 30 non-ESBL strains as ESBL-negative (yielding a sensitivity of 88% and a specificity of 76.7%, respectively). False negatives among ESBL producers were highest with Enterobacter spp. due to masking interactions between ESBL and AmpC beta-lactamases. False-positive classifications occurred in two Acinetobacter spp., one E. coli producing plasmid-mediated AmpC beta-lactamase and two K. oxytoca hyperproducing their chromosomal K1 beta-lactamase. The MicroScan clavulanate synergy test proved to be a valuable tool for ESBL confirmation. However, this test has limitations in detecting ESBLs in Enterobacter spp. and in discriminating ESBL-related resistance from the K1 enzyme and from inherent clavulanate susceptibility in Acinetobacter spp.

Therapeutic effect of cefozopran (SCE-2787), a new parenteral cephalosporin, against experimental infections in mice.

PubMed Central

Iizawa, Y; Okonogi, K; Hayashi, R; Iwahi, T; Yamazaki, T; Imada, A

1993-01-01

The therapeutic effect of cefozopran (SCE-2787), a new semisynthetic parenteral cephalosporin, against experimental infections in mice was examined. Cefozopran was more effective than cefpiramide and was as effective as ceftazidime and cefpirome against acute respiratory tract infections caused by Klebsiella pneumoniae DT-S. In the model of chronic respiratory tract infection caused by K. pneumoniae 27, cefozopran was as effective as ceftazidime. The therapeutic effect of cefozopran against urinary tract infections caused by Pseudomonas aeruginosa P9 was superior to that of cefpirome and was equal to those of ceftazidime and cefclidin. In addition, cefozopran was more effective than ceftazidime and was as effective as flomoxef in a thigh muscle infection caused by methicillin-sensitive Staphylococcus aureus 308A-1. Against thigh muscle infections caused by methicillin-resistant S. aureus N133, cefozopran was the most effective agent. The potent therapeutic effect of cefozopran in those experimental infections in mice suggests that it would be effective against respiratory tract, urinary tract, and soft tissue infections caused by a variety of gram-positive and gram-negative bacteria in humans. PMID:8431004

Gram-negative prosthetic joint infection: outcome of a debridement, antibiotics and implant retention approach. A large multicentre study.

PubMed

Rodríguez-Pardo, D; Pigrau, C; Lora-Tamayo, J; Soriano, A; del Toro, M D; Cobo, J; Palomino, J; Euba, G; Riera, M; Sánchez-Somolinos, M; Benito, N; Fernández-Sampedro, M; Sorli, L; Guio, L; Iribarren, J A; Baraia-Etxaburu, J M; Ramos, A; Bahamonde, A; Flores-Sánchez, X; Corona, P S; Ariza, J

2014-11-01

We aim to evaluate the epidemiology and outcome of gram-negative prosthetic joint infection (GN-PJI) treated with debridement, antibiotics and implant retention (DAIR), identify factors predictive of failure, and determine the impact of ciprofloxacin use on prognosis. We performed a retrospective, multicentre, observational study of GN-PJI diagnosed from 2003 through to 2010 in 16 Spanish hospitals. We define failure as persistence or reappearance of the inflammatory joint signs during follow-up, leading to unplanned surgery or repeat debridement>30 days from the index surgery related death, or suppressive antimicrobial therapy. Parameters predicting failure were analysed with a Cox regression model. A total of 242 patients (33% men; median age 76 years, interquartile range (IQR) 68-81) with 242 episodes of GN-PJI were studied. The implants included 150 (62%) hip, 85 (35%) knee, five (2%) shoulder and two (1%) elbow prostheses. There were 189 (78%) acute infections. Causative microorganisms were Enterobacteriaceae in 78%, Pseudomonas spp. in 20%, and other gram-negative bacilli in 2%. Overall, 19% of isolates were ciprofloxacin resistant. DAIR was used in 174 (72%) cases, with an overall success rate of 68%, which increased to 79% after a median of 25 months' follow-up in ciprofloxacin-susceptible GN-PJIs treated with ciprofloxacin. Ciprofloxacin treatment exhibited an independent protective effect (adjusted hazard ratio (aHR) 0.23; 95% CI, 0.13-0.40; p<0.001), whereas chronic renal impairment predicted failure (aHR, 2.56; 95% CI, 1.14-5.77; p 0.0232). Our results confirm a 79% success rate in ciprofloxacin-susceptible GN-PJI treated with debridement, ciprofloxacin and implant retention. New therapeutic strategies are needed for ciprofloxacin-resistant PJI. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

STREPTOCOCCI IN INFECTIOUS (ATROPHIC) ARTHRITIS AND RHEUMATIC FEVER.

PubMed

Nye, R N; Waxelbaum, E A

1930-11-30

The question of the relationship of streptococci to the etiology of infectious arthritis and of rheumatic fever is of the utmost importance. If a streptococcus or group of streptococci could be shown to be associated See PDF for Structure with either disease, some form of specific treatment might be available. The possibility of primary streptococcic infection as the cause of rheumatic fever, and, to a less extent, of acute infectious arthritis would seem to be a reasonable conjecture because of the frequency of associated throat, sinus or other focal infection. To consider that these same streptococci remain in or about the affected joint and to such an extent that they are found in the blood stream in cases of chronic infectious arthritis of years' duration demands a rather unique conception. Recent investigative work has certainly tended to confirm the importance of streptococci in these diseases, but, if all the published reports are considered as a group, one can not help being impressed with the inconsistency and peculiarities of the findings. In blood cultures from cases of rheumatic fever Clawson (7) recovered Streptococcus viridans, Small (8) and Birkhaug (9) non-hemolytic (gamma type) streptococci, and Cecil et al. (3) Streptococcus viridans, rarely hemolytic and non-hemolytic streptococci. In blood cultures from cases of infectious arthritis Cecil et al. (2) recovered attenuated hemolytic streptococci and occasionally Streptococcus viridans, non-hemolytic streptococci and diphtheroids and Margolis and Dorsey (10) green-producing and indifferent streptococci and diphtheroids, whereas from synovial fluids and regional lymph nodes Forkner, Shands and Poston (4) and Poston (5) obtained Streptococcus viridans and Margolis and Dorsey (11) recovered green-producing and indifferent streptococci and diphtheroids from epiphyseal marrows, bones and synovial membranes. On the other hand, Jordan (12) and Nye and Seegal (13) and the work reported in this paper have failed to confirm these findings. If a streptococcus is the infective agent, it is difficult to explain why the organisms recovered so consistently by certain groups of investigators are so different and why the findings of other groups are entirely negative. The chances of contamination, even with the most careful manipulation, are extremely favorable when using a cultural technique which demands subculturing a fluid medium every 3 to 5 days for a period of 4 to 6 weeks. The question arises as to what organisms should be considered as contaminants. Cultures found to contain Staphylococcus albus have never been judged significant. Margolis and Dorsey (11) have excluded Gram-positive bacilli from their series, but have included diphtheroids. Cecil et al. (2) reported the recovery of diphtheroids and Micrococcus zymogenes from blood cultures which they did not consider contaminated. Jordan (12) recovered short Gram-negative bacilli and Gram-positive bacilli and questioned their importance. The occurrence of such bacteria would appear to be not unlike that of the non-hemolytic (gamma type) streptococci reported by Small (7), Birkhaug (9) and, rarely, by Cecil et al. (2) and Margolis and Dorsey (10,11). In the work reported in this paper and in previously published work (13) with blood cultures from cases of rheumatic fever, staphylococci, Gram-positive bacilli and diplococci and diphtheroids have been isolated from a certain number of the cultures. Since these were found, as a rule, in only 1 of 2 or more cultures from the same blood and since such organisms occurred about as frequently in cultures from control cases, they have been considered merely contaminants. The findings in the 9 cases of arthritis with positive blood cultures reported by Margolis and Dorsey (10) are certainly far from convincing. These authors found green-producing streptococci in 5 of the 9 cases, but duplicate cultures on the same blood, with one exception, were always negative and the two repeat cultures were negative. Furthermore, in the 3 cases yielding indifferent streptococci in one subculture all subsequent subcultures were negative. In the work reported in this paper a green-producing and a non-hemolytic streptococcus were isolated from blood cultures, but a Gram-positive diplococcus and a Gram-positive bacillus, respectively, were recovered from the same cultures. A consideration of the above would seem to point to the probability, even certainty, of streptococci occurring in some cultures as contaminants; and the work of Olitsky and Long (14) and Long, Olitsky and Stewart (15) has clearly demonstrated that the air contamination of cultures of ground material with non-hemolytic green-producing streptococci can occur just as easily as with diphtheroids and staphylococci. It is obvious, in such cases, that the types of organisms recovered are dependent on the flora of the air of the laboratory or of the throat of the laboratory worker, and this point may well explain the differences in the cultural findings under consideration. A number of years ago numerous articles (16-19) appeared relative to the bacteriologic flora of lymph nodes, particularly those from cases of Hodgkin's disease, and it is interesting to note that the organisms recovered were quite similar to those which have been recovered from the blood and tissues of cases of arthritis and rheumatic fever, with the exception that the diphtheroids were, at that time, much more in prominence. Regardless of elaborate serological studies and animal experiments, streptococci must be recovered consistently by several groups of laboratory workers before their etiologic rôle in chronic arthritis and rheumatic fever can be accepted. Duplicate cultures and repeat cultures should yield the same organism in a generous percentage of cases and cultures from cases of other diseases or from normal persons should be negative. Positive cultures from duplicate cultures opened only at the time when the first culture showed growth would make the findings more significant than if the whole series were subcultured every 3 to 5 days. The work of Cecil, Nicholls and Stainsby on the bacteriology of the blood and joints in chronic arthritis and rheumatic fever has apparently been carried out most carefully and thoroughly and their results are very consistent and convincing. In spite of attempts to follow their methods in the selection of patients and in cultural technique, the results on the relatively small series of cases which are reported here fail to confirm their findings.

Pyramidobacter piscolens gen. nov., sp. nov., a member of the phylum 'Synergistetes' isolated from the human oral cavity.

PubMed

Downes, Julia; Vartoukian, Sonia R; Dewhirst, Floyd E; Izard, Jacques; Chen, Tsute; Yu, Wen-Han; Sutcliffe, Iain C; Wade, William G

2009-05-01

Four strains of anaerobic, Gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16S rRNA and 23S rRNA gene sequence analyses and DNA-DNA reassociation data revealed that the strains constituted a novel group within the phylum 'Synergistetes' and were most closely related to Jonquetella anthropi. Two libraries of randomly cloned DNA were prepared from strain W5455(T) and were sequenced to provide a genome survey as a resource for metagenomic studies. A new genus and novel species, Pyramidobacter piscolens gen. nov., sp. nov., is proposed to accommodate these strains. The genus Pyramidobacter comprises strains that are anaerobic, non-motile, asaccharolytic bacilli that produce acetic and isovaleric acids and minor to trace amounts of propionic, isobutyric, succinic and phenylacetic acids as end products of metabolism. P. piscolens gen. nov., sp. nov. produced hydrogen sulphide but was otherwise largely biochemically unreactive. Growth was stimulated by the addition of glycine to broth media. The G+C content of the DNA of the type strain was 59 mol%. The type strain of Pyramidobacter piscolens sp. nov. is W5455(T) (=DSM 21147(T)=CCUG 55836(T)).

Pyramidobacter piscolens gen. nov., sp. nov., a member of the phylum ‘Synergistetes’ isolated from the human oral cavity

PubMed Central

Downes, Julia; Vartoukian, Sonia R.; Dewhirst, Floyd E.; Izard, Jacques; Chen, Tsute; Yu, Wen-Han; Sutcliffe, Iain C.; Wade, William G.

2009-01-01

Four strains of anaerobic, Gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16S rRNA and 23S rRNA gene sequence analyses and DNA–DNA reassociation data revealed that the strains constituted a novel group within the phylum ‘Synergistetes’ and were most closely related to Jonquetella anthropi. Two libraries of randomly cloned DNA were prepared from strain W5455T and were sequenced to provide a genome survey as a resource for metagenomic studies. A new genus and novel species, Pyramidobacter piscolens gen. nov., sp. nov., is proposed to accommodate these strains. The genus Pyramidobacter comprises strains that are anaerobic, non-motile, asaccharolytic bacilli that produce acetic and isovaleric acids and minor to trace amounts of propionic, isobutyric, succinic and phenylacetic acids as end products of metabolism. P. piscolens gen. nov., sp. nov. produced hydrogen sulphide but was otherwise largely biochemically unreactive. Growth was stimulated by the addition of glycine to broth media. The G+C content of the DNA of the type strain was 59 mol%. The type strain of Pyramidobacter piscolens sp. nov. is W5455T (=DSM 21147T=CCUG 55836T). PMID:19406777

Rapid differentiation of cocci/mixed bacteria from rods in voided urine culture of women with uncomplicated urinary tract infections.

PubMed

Yang, Chun-Chun; Yang, Stephen Shei-Dei; Hung, Hui-Ching; Chiang, I-Ni; Peng, Chiung-Hui; Chang, Shang-Jen

2017-09-01

To evaluate the ability of laser flow cytometry to predict cocci/mixed growth in the pre-analytical phase of urine specimens. We retrospectively reviewed urine samples from women with uncomplicated urinary tract infections from urologic clinics for study. Urine analyses were performed with laser flow cytometry (UF1000i, Sysmex, Kobe, Japan) and then diagrams were generated (forward scatter vs. fluorescent light scatter). Each specimen (bacteria count >357 BACT/μL) was classified as either cocci bacteria or rods/mixed growth according to the diagrams. Standard urine cultures were performed, and the agreement between cultures and the UF1000i interpretations was analyzed with kappa statistics. Finally, 491 specimens met the criteria for analysis. Among the 376 specimens with single bacteria growth, there were 26 gram-positive cocci (13 Streptococci spp., 7 Staphylococci spp., 6 Enterococci spp.), 1 gram-positive rods (Corynebacterium spp.), and 349 gram-negative rods (273 Escherichia coli, 33 Klebsiella spp., 29 Proteus spp., 6 Citrobacter spp., 4 Enterobacter spp., 3 Pseudomonas spp., and 1 Providencia spp.). There were 115 specimens with two bacteria species or more that were regarded as mixed growth. Agreement of rods or cocci/mixed growth between the laser flow cytometry and urine cultures yielded a kappa value of 0.58. The positive and negative predictive rate of the UF1000i for cocci/mixed growth in voided urine culture was 81.8% and 84.7%, respectively. Through laser flow cytometry, we can predict growth of cocci/mixed growth in the pre-analytical phase of urine culture, thus avoiding unnecessary urine culture and waiting time. © 2016 Wiley Periodicals, Inc.

Antimicrobial susceptibility survey on bacterial agents of canine and feline urinary tract infections: Weight of the empirical treatment.

PubMed

Rampacci, Elisa; Bottinelli, Marco; Stefanetti, Valentina; Hyatt, Doreene R; Sgariglia, Elisa; Coletti, Mauro; Passamonti, Fabrizio

2018-06-01

This work characterised the antimicrobial susceptibility of uropathogens isolated from empirically treated dogs and cats. Within-household transmission of uropathogens can involve humans and companion animals. Knowledge on the prevalence and susceptibility pattern of isolates from canine and feline urine samples and the impact of prior antimicrobial treatment is important to prevent the dissemination of antimicrobial resistance. A retrospective study was conducted selecting antibiotic-treated companion animals. Urine samples were collected by cystocentesis and were submitted to an Italian diagnostic laboratory over a 2-year period (2013-2015). The antimicrobial susceptibility of the isolates was analysed both using Clinical and Laboratory Standards Institute (CLSI) guidelines and a formula to help select rational antimicrobial therapy. Gram-negative bacteria were clearly prevalent. Gentamicin had the highest impact factors. Amoxicillin/clavulanic acid and doxycycline appeared to be the most effective compounds against Gram-positive infections, whilst marbofloxacin may be a useful option against Gram-negative urinary tract infections (UTIs) as well as doxycycline and trimethoprim/sulfamethoxazole in cats and dogs, respectively. Consulting published studies, a comparable overall trend regarding bacterial species incriminated in canine and feline UTIs and their susceptibilities seems likely, despite different circumstances where the studies were conducted. Companion animals are potential reservoirs of drug-resistant uropathogens. Judicious use of antibiotics is necessary to maintain the efficacy of antimicrobials in human and veterinary medicine. Antimicrobial susceptibility monitoring programmes are therefore essential to facilitate the choice of antimicrobial agent that is most likely to be effective, particularly in cases of prior antimicrobial treatment. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. All rights reserved.

Bacterial flora of combat wounds from eastern Ukraine and time-specified changes of bacterial recovery during treatment in Ukrainian military hospital.

PubMed

Valentine, Kovalchuk P; Viacheslav, Kondratiuk M

2017-04-07

Microbiology of modern war wounds is unique for each military conflict. Climatic and geographical features of the theater of war, contemporary warfare as well as wound management affect the microbial flora of wounds. This study was designed to determine time-specific microbial flora of combat wounds of upper and lower extremities obtained during the war in eastern Ukraine. The patients enrolled in study had combat wounds of upper or lower extremities which were treated in the Military Medical Clinical Center of Central Region. The wounds were swab-cultured and measured at each surgical debridement. The recovered microorganisms were identified and their antimicrobial resistance profiles were evaluated by disc diffusion method. Forty-nine patients with battle-field wounds were enrolled in the study from July to November 2014; all patients were male with a mean Injury Severity Score and arrival APACHE II scores of 16.2 ± 10.7 and 7.4 ± 4.2 respectively. Among 128 swab cultures, 100 swab cultures were positive. Swab cultures were obtained from 57 wounds of 49 patients. The results of the test showed that 87.7% of all positive swab cultures contained a single-organism while the rest of the swab-culture results showed polymicrobial growth. Among the isolated microorganisms 65% (76 strains) were Gram-negative rods, 22.2% (26 strains) of Gram-positive cocci, followed by Gram-positive rods (12.8%, 15 strains). We found that epidemiology of wound infection changes with the time after injury. The most common bacterial isolates cultured during the first week were Gram-positive microbes with low pathogenicity. The number of Gram-negative rods increased during the wound healing process. The incidence of Gram-positive microorganisms' growth fell after the first week and increased after third week. During wound healing, bacterial microflora of wounds changes with increasing number of Gram-negative rods with predominance of Acinetobacter species. Predominant microorganisms in positive swab-cultures after first week were nonfermentative Gram-negative bacilli (68% of swab-cultures), which in 53% of the swab-cultures belonged to the genus Acinetobacter, and in 15% to the genus Pseudomonas. The incidence of polymicrobial wound cultures increased from first week to second post-injury week. The most frequent microbial mixture were Acinetobacter baumannii with Enterobacteriaceae or other nonfermentative Gram negative rods with Enterococcus spp. We observed bacteria recovery from wounds during proliferation phase. These wounds had no pure inflammation signs and were free of devitalized tissues. Any wound is at some risk of becoming infected. In the event of infection, a wound fails to heal, treatment costs rise, and general wound management practices become more resource demanding. Determining the microorganisms which colonize battle wounds and cause wound infection is paramount. This information can help to treat battle wound infections or even changes infection control strategies. The fact of shifting in wound microbiology in the favor of bacteria responsible for healthcare-associated infections support to the proposition that these changes are nosocomially related [4, 14]. For Ukrainian military medicine this study is the first time-specified assessment of battle wound colonization from the World War II.

Interplay of the Quality of Ciprofloxacin and Antibiotic Resistance in Developing Countries

PubMed Central

Sharma, Deepali; Patel, Rahul P.; Zaidi, Syed Tabish R.; Sarker, Md. Moklesur Rahman; Lean, Qi Ying; Ming, Long C.

2017-01-01

Ciprofloxacin, a second generation broad spectrum fluoroquinolone, is active against both Gram-positive and Gram-negative bacteria. Ciprofloxacin has a high oral bioavailability and a large volume of distribution. It is used for the treatment of a wide range of infections including urinary tract infections caused by susceptible bacteria. However, the availability and use of substandard and spurious quality of oral ciprofloxacin formulations in the developing countries has been thought to have contributed toward increased risk of treatment failure and bacterial resistance. Therefore, quality control and bioequivalence studies of the commercially available oral ciprofloxacin formulations should be monitored. Appropriate actions should be taken against offending manufacturers in order to prevent the sale of substandard and spurious quality of ciprofloxacin formulations. PMID:28871228

Variation in Antibiotic Susceptibility of Uropathogens by Age among Ambulatory Pediatric Patients

PubMed Central

Quach, Yennie; Bearden, David T.; Smith, David H.; Sharp, Susan E.; Guzman-Cottrill, Judith A.

2013-01-01

We compared uropathogen antibiotic susceptibility across age groups of ambulatory pediatric patients. For Escherichia coli (n=5,099) and other Gram-negative rods (n=626), significant differences (p<0.05) existed across age groups for ampicillin, cefazolin, and trimethoprim/sulfamethoxazole susceptibility. In E. coli, differences in trimethoprim/sulfamethoxazole susceptibility varied from 79% in children under 2 to 88% in ages 16–18 (p<0.001) while ampicillin susceptibility varied from 30% in children under 2 to 53% in ages 2–5 (p=0.015). Uropathogen susceptibility to common urinary anti-infectives may be lower in the youngest children. Further investigation into these differences is needed to facilitate appropriate and prudent treatment of urinary tract infections. PMID:24091131

Polymicrobial nature of vaginitis in young women: a microbiological and therapeutic study.

PubMed

Kippax, R A; Caradoc-Davies, G; Meech, R J

1982-03-24

Thirty-six young females attending the Student Health Service with vaginitis were investigated by serial semiquantitative aerobic, anaerobic, fungal, mycoplasma and viral cultures over a 10 day period and results were correlated with signs and symptoms. Antifungal therapy (econazole pessaries and cream) resulted in clearance of candida from 13 out of 16 patients where there was no increase in the anaerobic flora. In the four subjects where candida was isolated along with Gardnerella vaginalis plus abnormal anaerobic flora, only one cleared with econazole, the remaining three clearing during therapy with metronidazole. In the nine subjects with Gardnerella vaginalis and abnormal anaerobic flora, metronidazole relieved symptoms despite failure to eradicate G. vaginalis in seven indicating the pathogenic role of the anaerobic flora rather then G. vaginalis. Mycoplasma hominis, Ureaplasma urealyticum and gram negative enteric bacilli were not implicated as primary agents in causing vaginitis.

Intestinal perforation in typhoid fever: a historical and state-of-the-art review.

PubMed

Bitar, R; Tarpley, J

1985-01-01

The appropriate therapy for intestinal perforation in typhoid fever has been controversial since the late 1880s. Around the turn of the century, surgery became the established mode of therapy, with a mortality of 69% based on 166 patients in the English-language medical literature, and continued to be the preferred treatment until the advent of chloramphenicol in 1948. At this time the surgical mortality was approximately 50%. Following the recovery of a few patients with perforation treated only with antimicrobial agents (six initially, then eventually 22), nonsurgical therapy became the accepted mode of treatment. This change was never justified and this review demonstrates this. Appropriate therapy is virtually always surgical, usually consisting of simple closure and irrigation. Chloramphenicol alone is inadequate antimicrobial therapy in a patient with perforation and must be supplemented by other antimicrobials directed against enteric aerobic gram-negative bacilli and enteric anaerobes.

Antimicrobial-resistant Klebsiella species isolated from free-range chicken samples in an informal settlement.

PubMed

Fielding, Burtram C; Mnabisa, Amanda; Gouws, Pieter A; Morris, Thureyah

2012-02-29

Sub-therapeutic doses of antimicrobial agents are administered routinely to poultry to aid growth and to prevent disease, with prolonged exposure often resulting in bacterial resistance. Crossover of antibiotic resistant bacteria from poultry to humans poses a risk to human health. In this study, 17 chicken samples collected from a vendor operating in an informal settlement in the Cape Town Metropolitan area, South Africa were screened for antimicrobial-resistant Gram-negative bacilli using the Kirby Bauer disk diffusion assay. IN TOTAL, SIX ANTIBIOTICS WERE SCREENED: ampicillin, ciprofloxacin, gentamicin, nalidixic acid, tetracycline and trimethoprim. Surprisingly, Klebsiella ozaenae was identified in 96 and K. rhinoscleromatis in 6 (n=102) of the samples tested. Interestingly, ∼40% of the isolated Klebsiella spp. showed multiple resistance to at least three of the six antibiotics tested. Klebsiella ozaenae and K. rhinoscleromatis cause clinical chronic rhinitis and are almost exclusively associated with people living in areas of poor hygiene.

A two-hour antibiotic susceptibility test by ATP-bioluminescence.

PubMed

March Rosselló, Gabriel Alberto; García-Loygorri Jordán de Urries, María Cristina; Gutiérrez Rodríguez, María Purificación; Simarro Grande, María; Orduña Domingo, Antonio; Bratos Pérez, Miguel Ángel

2016-01-01

The antibiotic susceptibility test (AST) in Clinical Microbiology laboratories is still time-consuming, and most procedures take 24h to yield results. In this study, a rapid antimicrobial susceptibility test using ATP-bioluminescence has been developed. The design of method was performed using five ATCC collection strains of known susceptibility. This procedure was then validated against standard commercial methods on 10 strains of enterococci, 10 staphylococci, 10 non-fermenting gram negative bacilli, and 13 Enterobacteriaceae from patients. The agreement obtained in the sensitivity between the ATP-bioluminescence method and commercial methods (E-test, MicroScan and VITEK2) was 100%. In summary, the preliminary results obtained in this work show that the ATP-bioluminescence method could provide a fast and reliable AST in two hours. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Structure, Function, and Assembly of Adhesive Organelles by Uropathogenic Bacteria

PubMed Central

Chahales, Peter; Thanassi, David G.

2015-01-01

Bacteria assemble a wide range of adhesive proteins, termed adhesins, to mediate binding to receptors and colonization of surfaces. For pathogenic bacteria, adhesins are critical for early stages of infection, allowing the bacteria to initiate contact with host cells, colonize different tissues, and establish a foothold within the host. The adhesins expressed by a pathogen are also critical for bacterial-bacterial interactions and the formation of bacterial communities such as biofilms. The ability to adhere to host tissues is particularly important for bacteria that colonize sites such as the urinary tract, where the flow of urine functions to maintain sterility by washing away non-adherent pathogens. Adhesins vary from monomeric proteins that are directly anchored to the bacterial surface to polymeric, hairlike fibers that extend out from the cell surface. These latter fibers are termed pili or fimbriae, and were among the first identified virulence factors of uropathogenic Escherichia coli. Studies since then have identified a range of both pilus and non-pilus adhesins that contribute to bacterial colonization of the urinary tract, and have revealed molecular details of the structures, assembly pathways, and functions of these adhesive organelles. In this review, we describe the different types of adhesins expressed by both Gram-negative and Gram-positive uropathogens, what is known about their structures, how they are assembled on the bacterial surface, and the functions of specific adhesins in the pathogenesis of urinary tract infections. PMID:26542038

Antibiotic sensitivity pattern from pregnant women with urinary tract infection in Bangalore, India.

PubMed

Sibi, G; Kumari, Pinki; Kabungulundabungi, Neema

2014-09-01

To determine the antibacterial profile of pregnant women with urinaty tract infections and analyze the antibiotic sensitivity pattern for the effective treatment. A total of 395 urine samples from pregnant women with different gestational age were processed for the isolation of uropathogens and tested against eight groups of antibiotics namely penicillins, cephalosporins, fluoroquinolones, aminoglycosides, macrolides, lincosamides, glycopeptides and sulfonamides. A positive culture percentage of 46.6% was obtained with the highest urinary tract infection in third trimester gestational age. Among the uropathogens isolated, 85.6% were Gram negative and 14.4% were Gram positive with Escherichia coli as the predominant bacteria (43.9%) followed by Klebsiella oxytoca (19.4%) and Klebsiella pneumoniae (13.3%). Antibiotic sensitivity assay revealed that amikacin had the highest overall sensitivity (n=136; 76.7%) and the subsequent highest sensitivity was observed with ciprofloxacin (n=132; 73.3%), clindamycin (n=124; 68.9%), cefotaxime (n=117; 65%) and nalidixic acid (n=115; 63.9%). The findings revealed that uropathogens were more resistant to penicillins, macrolides and glycopeptides which restrict their use in treating urinaty tract infections during pregnancy. In conclusion, common causative bacteria and their antibiotic sensitivity pattern are to be determined along with their safety to mother and fetus for the effective treatment of urinary tract infections during pregnancy. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Comparative Evaluation of Multiplex PCR and Routine Laboratory Phenotypic Methods for Detection of Carbapenemases among Gram Negative Bacilli.

PubMed

Solanki, Rachana; Vanjari, Lavanya; Subramanian, Sreevidya; B, Aparna; E, Nagapriyanka; Lakshmi, Vemu

2014-12-01

Carbapenem resistant pathogens cause infections associated with significant morbidity and mortality. This study evaluates the use of Multiplex PCR for rapid detection of carbapenemase genes among carbapenem resistant Gram negative bacteria in comparison with the existing phenotypic methods like modified Hodge test (MHT), combined disc test (CDT) and automated methods. A total of 100 Carbapenem resistant clinical isolates, [Escherichia coli (25), Klebsiella pneumoniae (35) P. aeruginosa (18) and Acinetobacter baumannii (22)] were screened for the presence of carbapenemases (bla NDM-1, bla VIM , blaIMP and blaKPC genes) by phenotype methods such as the modified Hodge test (MHT) and combined disc test (CDT) and the molecular methods such as Multiplex PCR. Seventy of the 100 isolates were MHT positive while, 65 isolates were positive by CDT. All the CDT positive isolates with EDTA and APB were Metallo betalactamase (MBL) and K. pneumoniae carbapenemase (KPC) producers respectively. bla NDM-1 was present as a lone gene in 44 isolates. In 14 isolates bla NDM-1 gene was present with blaKPC gene, and in one isolate bla NDM-1 gene was present with blaVIM , gene. Only one E. coli isolate had a lone blaKPC gene. We didn't find bla IMP gene in any of the isolates. Neither of the genes could be detected in 35 isolates. Accurate detection of the genes related with carbapenemase production by Molecular methods like Multiplex PCR overcome the limitations of the phenotypic methods and Automated systems.

Characterization of indoor bioaerosols from a hospital ward in a tropical setting.

PubMed

Sudharsanam, S; Swaminathan, S; Ramalingam, A; Thangavel, G; Annamalai, R; Steinberg, R; Balakrishnan, K; Srikanth, P

2012-06-01

Study was conducted to assess whether temporal variation exists in airborne microbial concentrations of a hospital ward (west-Chennai, India) using active and passive methods, and characterise the microorganisms. Air samples (duplicates) were collected simultaneously using exposed-plate, impingement (BioSampler) and filtration (personal sampling filter cassette loaded with gelatin filter) methods over different periods of the year. Bacterial plates were incubated at 37°C and observed for growth after 48h; fungal plates were incubated at 25°C and 37°C and observed upto 7 days. Microorganisms were identified using standard microbiological procedures. Microbial loads were found to vary with the sampling method. Concentrations of bacteria were higher (exposed-plate: 45-150 CFU/plate; impingement: 1.12E+03-1.6856E+05 CFU/m(3); filtration: 3.788E+03-1.91111E+05 CFU/m(3)) than fungi (exposed-plate: 0-13 CFU/plate; impingement: 0-3.547E+03 CFU/m(3); filtration: 0-1.515E+04 CFU/ m(3)). Coagulase-negative Staphylococci and Micrococci were the predominant Gram-positive cocci in active and passive samples. Enterobacter and Pseudomonas were the predominant Gram-negative bacilli. Among fungi, Aspergillus niger was isolated throughout the year. There was no significant temporal variation in airborne microbial loads irrespective of methods. Exposed-plate method was found to capture microorganisms efficiently with little variation in duplicate samples, suggesting its use in hospitals for preliminary assessment of indoor air quality and determine pathogenic microorganisms due to particle fall-out.

Ventilator-associated pneumonia at a tertiary-care center in a developing country: incidence, microbiology, and susceptibility patterns of isolated microorganisms.

PubMed

Kanafani, Zeina A; Kara, Layla; Hayek, Shady; Kanj, Souha S

2003-11-01

Ventilator-associated pneumonia (VAP) complicates the course of up to 24% of intubated patients. Data from the Middle East are scarce. The objective of this study was to evaluate the incidence, microbiology, and antimicrobial susceptibility patterns of isolated microorganisms in VAP in a developing country. Prospective observational cohort study. The American University of Beirut Medical Center, a tertiary-care center that serves as a major referral center for Lebanon and neighboring countries. All patients admitted to the intensive care and respiratory care units from March to September 2001, and who had been receiving mechanical ventilation for at least 48 hours, were included in the study. Results of samples submitted for culture were recorded and antimicrobial susceptibility testing of isolated pathogens was performed. Seventy patients were entered into the study. The incidence of VAP was 47%. Gram-negative bacilli accounted for 83% of all isolates. The most commonly identified organism was Acinetobacter anitratus, followed by Pseudomonas aeruginosa. Fifty percent of all gram-negative bacterial isolates were classified as antibiotic resistant. Compared with patients without VAP, patients with VAP remained intubated for a longer period and stayed in the intensive care unit longer. VAP was not associated with an increased mortality rate. Compared with other studies, the results from this referral center in Lebanon indicate a higher incidence of VAP and a high prevalence of resistant organisms. These data are relevant because they direct the choice of empiric antibiotic therapy for VAP.

Triton Hodge Test: Improved Protocol for Modified Hodge Test for Enhanced Detection of NDM and Other Carbapenemase Producers

PubMed Central

Pasteran, Fernando; Gonzalez, Lisandro J.; Albornoz, Ezequiel; Bahr, Guillermo; Vila, Alejandro J.

2015-01-01

Accurate detection of carbapenemase-producing Gram-negative bacilli is of utmost importance for the control of nosocomial spread and the initiation of appropriate antimicrobial therapy. The modified Hodge test (MHT), a carbapenem inactivation assay, has shown poor sensitivity in detecting the worldwide spread of New Delhi metallo-β-lactamase (NDM). Recent studies demonstrated that NDM is a lipoprotein anchored to the outer membrane in Gram-negative bacteria, unlike all other known carbapenemases. Here we report that membrane anchoring of β-lactamases precludes detection of carbapenemase activity by the MHT. We also show that this limitation can be overcome by the addition of Triton X-100 during the test, which allows detection of NDM. We propose an improved version of the assay, called the Triton Hodge test (THT), which allows detection of membrane-bound carbapenemases with the addition of this nonionic surfactant. This test was challenged with a panel of 185 clinical isolates (145 carrying known carbapenemase-encoding genes and 40 carbapenemase nonproducers). The THT displayed test sensitivity of >90% against NDM-producing clinical isolates, while improving performance against other carbapenemases. Ertapenem provided the highest sensitivity (97 to 100%, depending on the type of carbapenemase), followed by meropenem (92.5 to 100%). Test specificity was not affected by the addition of Triton (87.5% and 92.5% with ertapenem and meropenem, respectively). This simple inexpensive test confers a large improvement to the sensitivity of the MHT for the detection of NDM and other carbapenemases. PMID:26719442

[Acute meningitis in Córdoba, Colombia (2002-2004)].

PubMed

Tique, Vaneza; Alvis, Nelson; Parodi, Renata; Bustos, Alvaro; Mattar, Salim

2006-05-01

Establishing characteristic epidemiologic and microbiologic features of acute meningitis in the Córdoba department. A descriptive epidemiological study was carried out between June 2002 and June 2004 at the Hospital San Jerónimo in Montería. All suspicious cases of meningitis were included; laboratory tests included cytological smear, biochemistry, latex, Gram stain and culture. 57 (11.3%) and 85 (16.8%) of the 503 samples of cerebrum spinal fluid (CSF) were confirmed by culture as being probable cases. There were 6 cases of polymicrobial infection, making a total of 63 isolates: 17 non-fermenting Gram-negative bacilli (26.9%), 16 Streptococcus pneumoniae (25.4%), 7 Enterobacteriaceae (11%), 5 Criptococcus neoformans (8%) 4 Neisseria meningitidis serotype B (6.3%), 3 S. viridans (4.8%), 2 Streptococcus group B (3.2%), 2 Haemophilus influenzae type B (3.2%), 2 Staphylococcus negative coagulase (3.2%), 2 S. aureus (3.2%), 2 Enterococcus (3.2%) and 1 Candida albicans (1.6%). The S. Pneumoniae serotypes found were: 5 (n=4), 23F (n=3), 14 (n=2), 18C (n=2), 18A (n=l1, 17F (n=l1, 1 (n=1). The study led to determining epidemiological and microbiological aspects of acute meningitis in the Códoba department which had been unknown up to now. Streptococcus pneumoniae (25.4% was the main aetiological agent of meningitis; the epidemiologic aspects so established confirmed the need for strengthening and implementing measures for controlling meningitis in C6ódoba and its surveillance there.

Carbapenem-resistant Gram-negative bacilli in Canada 2009-10: results from the Canadian Nosocomial Infection Surveillance Program (CNISP).

PubMed

Mataseje, L F; Bryce, E; Roscoe, D; Boyd, D A; Embree, J; Gravel, D; Katz, K; Kibsey, P; Kuhn, M; Mounchili, A; Simor, A; Taylor, G; Thomas, E; Turgeon, N; Mulvey, M R

2012-06-01

To investigate the occurrence and molecular mechanisms associated with carbapenemases in carbapenem-resistant Gram-negative isolates from Canadian cases. Twenty hospital sites across Canada submitted isolates for a 1 year period starting 1 September 2009. All Enterobacteriaceae with MICs ≥ 2 mg/L and Acinetobacter baumannii and Pseudomonas aeruginosa with MICs ≥ 16 mg/L of carbapenems were submitted to the National Microbiology Laboratory (NML) where carbapenem MICs were confirmed by Etest and isolates were characterized by PCR for carbapenemase genes, antimicrobial susceptibilities, PFGE and plasmid isolation. A total of 444 isolates (298 P. aeruginosa, 134 Enterobacteriaceae and 12 A. baumannii) were submitted to the NML of which 274 (61.7%; 206 P. aeruginosa, 59 Enterobacteriaceae and 9 A. baumannii) met the inclusion criteria as determined by Etest. Carbapenemase genes were identified in 30 isolates: bla(GES-5) (n = 3; P. aeruginosa), bla(KPC-3) (n = 7; Enterobacteriaceae), bla(NDM-1) (n = 2; Enterobacteriaceae), bla(VIM-2) and bla(VIM-4) (n = 8; P. aeruginosa) bla(SME-2) (n = 1; Enterobacteriaceae) and bla(OXA-23) (n = m9; A. baumannii). PFGE identified a cluster in each of Enterobacteriaceae, P. aeruginosa and A. baumannii corresponding to isolates harbouring carbapenemase genes. Three KPC plasmid patterns (IncN and FllA) were identified where indistinguishable plasmid patterns were identified in unrelated clinical isolates. Carbapenemases were rare at the time of this study. Dissemination of carbapenemases was due to both dominant clones and common plasmid backbones.

The Genus Corynebacterium and Other Medically Relevant Coryneform-Like Bacteria

PubMed Central

2012-01-01

Catalase-positive Gram-positive bacilli, commonly called “diphtheroids” or “coryneform” bacteria were historically nearly always dismissed as contaminants when recovered from patients, but increasingly have been implicated as the cause of significant infections. These taxa have been underreported, and the taxa were taxonomically confusing. The mechanisms of pathogenesis, especially for newly described taxa, were rarely studied. Antibiotic susceptibility data were relatively scant. In this minireview, clinical relevance, phenotypic and genetic identification methods, matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) evaluations, and antimicrobial susceptibility testing involving species in the genus Corynebacterium and other medically relevant Gram-positive rods, collectively called coryneforms, are described. PMID:22837327

Urinary tract infection among fistula patients admitted at Hamlin fistula hospital, Addis Ababa, Ethiopia.

PubMed

Dereje, Matifan; Woldeamanuel, Yimtubezinesh; Asrat, Daneil; Ayenachew, Fekade

2017-02-16

Urinary Tract Infection (UTI) causes a serious health problem and affects millions of people worldwide. Patients with obstetric fistula usually suffer from incontinence of urine and stool, which can predispose them to frequent infections of the urinary tract. Therefore the aim of this study was to determine the etiologic agents, drug resistance pattern of the isolates and associated risk factor for urinary tract infection among fistula patients in Addis Ababa fistula hospital, Ethiopia. Across sectional study was conducted from February to May 2015 at Hamlin Fistula Hospital, Addis Ababa, Ethiopia. Socio-demographic characteristics and other UTI related risk factors were collected from study participants using structured questionnaires. The mid-stream urine was collected and cultured on Cysteine lactose electrolyte deficient agar and blood agar. Antimicrobial susceptibility was done by using disc diffusion method and interpreted according to Clinical and Laboratory Standards Institute (CLSI). Data was entered and analyzed by using SPSS version 20. Out of 210 fistula patients investigated 169(80.5%) of the patient were younger than 25 years. Significant bacteriuria was observed in 122/210(58.1%) and 68(55.7%) of the isolates were from symptomatic cases. E.coli 65(53.7%) were the most common bacterial pathogen isolated followed by Proteus spp. 31(25.4%). Statistical Significant difference was observed with history of previous UTI (P = 0.031) and history of catheterization (P = 0.001). Gram negative bacteria isolates showed high level of resistance (>50%) to gentamicin and ciprofloxacin, while all gram positive bacteria isolated were showed low level of resistance (20-40%) to most of antibiotic tested. The overall prevalence of urinary tract infection among fistula patient is 58.1%. This study showed that the predominant pathogen of UTI were E.coli followed by Proteus spp. It also showed that amoxicillin-clavulanic acid was a drug of choice for urinary tract bacterial pathogens.

Tuberculous prostatitis: mimicking a cancer.

PubMed

Aziz, El Majdoub; Abdelhak, Khallouk; Hassan, Farih Moulay

2016-01-01

Genitourinary tuberculosis is a common type of extra-pulmonary tuberculosis . The kidneys, ureter, bladder or genital organs are usually involved. Tuberculosis of the prostate has mainly been described in immune-compromised patients. However, it can exceptionally be found as an isolated lesion in immune-competent patients. Tuberculosis of the prostate may be difficult to differentiate from carcinoma of the prostate and the chronic prostatitis when the prostate is hard and nodular on digital rectal examination and the urine is negative for tuberculosis bacilli. In many cases, a diagnosis of tuberculous prostatitis is made by the pathologist, or the disease is found incidentally after transurethral resection. Therefore, suspicion of tuberculous prostatitis requires a confirmatory biopsy of the prostate. We report the case of 60-year-old man who presented a low urinary tract syndrome. After clinical and biological examination, and imaging, prostate cancer was highly suspected. Transrectal needle biopsy of the prostate was performed and histological examination showed tuberculosis lesions.

Virulence factors and resistance mechanisms of Serratia marcescens. A short review.

PubMed

Rodrigues, Ana P; Holanda, A R M; Lustosa, G P; Nóbrega, S M B; Santana, Willma J; Souza, Luciana B S; Coutinho, H D M

2006-03-01

Serratia marcescens, a Gram-negative bacillus that belongs to the family Enterobacteriaceae, is a human opportunistic pathogen bacterium that causes many diseases, such as urinary tract infections, respiratory tract infections, bacteremia, conjunctivitis, endocarditis, meningitis and wound infections. Many plasmides that confers multi-drug resistance were discovered, such as virulence factors, like cytotoxins that damage epithelial cells. The main topic of this paper presents a review about the molecular traits evolved in the pathogenic processes mediated by Serratia and its mechanism of resistance to drugs.

Improved system for floor cleaning in health care facilities.

PubMed Central

Schmidt, E A; Coleman, D L; Mallison, G F

1984-01-01

A new system has been developed for sanitizing floors in hospitals; this system replaces the traditional procedure of daily dusting and wet mopping with a disinfectant-detergent solution and periodic buffing . This new system relies on a sequence of procedures consisting of dust mopping using a chemically treated dust mop, machine buffing of a sprayed-on polymer treatment, and a second dust mopping . The effectiveness of the procedures was evaluated by means of surface sampling for bacterial contamination and air sampling for airborne bacteria and dust. The level of bacterial contamination on the floors was reduced by 93.6% by using the new system, compared with 79.8% by using the conventional process of dust mopping and wet mopping with a disinfectant solution. The levels of airborne bacteria during and after the individual procedures did not vary significantly from the initial level (123.6 CFU/per m3 of air). A survey of representative colonies from air samples revealed staphylococci, gram-positive bacilli, gram-positive diplococci, yeast cells, and infrequent gram-negative rods. The distribution at the conclusion of the sanitizing process was similar to that at the outset. Similarly, the levels of airborne dust measured during and after the individual procedures did not vary significantly from the initial level. When compared with the traditional method of cleaning by wet mopping , the new method was significantly more effective in removal of microbial contamination and required less labor. PMID:6742835

Isolation of Clostridium perfringens type A from wild bharals (Pseudois nayaur) following sudden death in Tibet, China.

PubMed

Zhu, Lingwei; Zhou, Wei; Wang, Tiecheng; Xiang, Haiyang; Ji, Xue; Han, Yixiao; Tian, Yuan; Sun, Yang; Liu, Jun; Guo, Xuejun

2017-04-01

Dozens of wild bharals died suddenly in Tibet. Necropsy showed severe congestion and hemorrhage in multiple organs, with large numbers of Gram-positive bacilli. Strains of Clostridium perfringens type A were isolated from the different organs and the intestinal contents. The other possible pathogens were ruled out by PCR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Female genital tract bacterial coisolates with Candida albicans in patients without clinical vaginitis.

PubMed Central

Monif, G R; Carson, H J

1998-01-01

OBJECTIVE: In vitro, Candida albicans has demonstrated the ability to inhibit replication of selected bacteria. Little information exists on the impact of C. albicans on the vaginal bacterial flora in vivo. The purpose of this study is to identify the coexisting bacterial flora when C. albicans is isolated from vaginal cultures submitted to a hospital-based testing facility for reasons other than vulvovaginitis. METHODOLOGY: All specimens (240) received from ambulatory care clinics over a six-month period were cultured for aerobic and anaerobic bacteria and Candida species. Those specimens submitted for cervicitis, vaginitis, or vaginal discharge and those from which yeasts other than C. albicans were isolated were eliminated. To control for sample biases, a subgroup composed of all pregnant women for whom cultures were done as screening procedures was similarly studied. Chi-square analyses, comparing the prevalence of individual bacteria isolated with and without the presence of C. albicans, were done for all study populations using SPSS for Windows software (1994). RESULTS: Two hundred and forty consecutive specimens were bacteriologically analyzed. Of the 220 vaginal samples used in the study, C. albicans was isolated in 44 instances (20%). Neither the presence of the lactobacilli nor the presence of Gardnerella vaginalis markedly influenced the isolation rate of C. albicans. The group B streptococci had a greater probability of coisolation when C. albicans was present (27.3% verses 16%), but this was not statistically significant (P < 0.8). Dissociation between the presence of C. albicans and the coisolation of Peptostreptococcus species and anaerobic gram-positive cocci and/or bacilli was noted (P < 0.0819), while the incidence of gram-positive aerobic bacilli was reduced in the presence of C. albicans (30/176 [17.1%] versus 6/44 [13.6%]), this reduced incidence was not statistically significant. Isolation data of the subgroup of pregnant women supported these observations. CONCLUSION: Within the limitations of the study, statistically, the data suggests that an inverse relationship exists between the presence of C. albicans and recovery of Peptostreptococcus and anaerobic gram-positive cocci and bacilli. PMID:9702585

Female genital tract bacterial coisolates with Candida albicans in patients without clinical vaginitis.

PubMed

Monif, G R; Carson, H J

1998-01-01

In vitro, Candida albicans has demonstrated the ability to inhibit replication of selected bacteria. Little information exists on the impact of C. albicans on the vaginal bacterial flora in vivo. The purpose of this study is to identify the coexisting bacterial flora when C. albicans is isolated from vaginal cultures submitted to a hospital-based testing facility for reasons other than vulvovaginitis. All specimens (240) received from ambulatory care clinics over a six-month period were cultured for aerobic and anaerobic bacteria and Candida species. Those specimens submitted for cervicitis, vaginitis, or vaginal discharge and those from which yeasts other than C. albicans were isolated were eliminated. To control for sample biases, a subgroup composed of all pregnant women for whom cultures were done as screening procedures was similarly studied. Chi-square analyses, comparing the prevalence of individual bacteria isolated with and without the presence of C. albicans, were done for all study populations using SPSS for Windows software (1994). Two hundred and forty consecutive specimens were bacteriologically analyzed. Of the 220 vaginal samples used in the study, C. albicans was isolated in 44 instances (20%). Neither the presence of the lactobacilli nor the presence of Gardnerella vaginalis markedly influenced the isolation rate of C. albicans. The group B streptococci had a greater probability of coisolation when C. albicans was present (27.3% verses 16%), but this was not statistically significant (P < 0.8). Dissociation between the presence of C. albicans and the coisolation of Peptostreptococcus species and anaerobic gram-positive cocci and/or bacilli was noted (P < 0.0819), while the incidence of gram-positive aerobic bacilli was reduced in the presence of C. albicans (30/176 [17.1%] versus 6/44 [13.6%]), this reduced incidence was not statistically significant. Isolation data of the subgroup of pregnant women supported these observations. Within the limitations of the study, statistically, the data suggests that an inverse relationship exists between the presence of C. albicans and recovery of Peptostreptococcus and anaerobic gram-positive cocci and bacilli.

Pure neuritic leprosy: Resolving diagnostic issues in acid fast bacilli (AFB)-negative nerve biopsies: A single centre experience from South India

PubMed Central

Hui, Monalisa; Uppin, Megha S.; Challa, Sundaram; Meena, A. K.; Kaul, Subhash

2015-01-01

Background and Purpose: Demonstration of lepra bacilli is essential for definite or unequivocal diagnosis of pure neuritic leprosy (PNL) on nerve biopsy. However, nerves always do not show bacilli owing to the changes of previous therapy or due to low bacillary load in tuberculoid forms. In absence of granuloma or lepra bacilli, other morphologic changes in endoneurium and perineurium can be of help in making a probable diagnosis of PNL and treating the patient with multidrug therapy. Materials and Methods: Forty-six biopsies of PNL were retrospectively reviewed and histologic findings were compared with 25 biopsies of non leprosy neuropathies (NLN) including vasculitic neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP). The distribution of endoneurial infiltrate and fibrosis, perineurial thickening, and myelin abnormalities were compared between PNL and NLN biopsies and analyzed by Chi-square test. Results: Out of 46 PNL casses, 24 (52.17 %) biopsies were negative for acid fast bacilli (AFB). In these cases, the features which favor a diagnosis of AFB-negative PNL were endoneurial infiltrate (51.1%), endoneurial fibrosis (54.2%), perineurial thickening (70.8%), and reduced number of myelinated nerve fibers (75%). Interpretation and Conclusion: Nerve biopsy is an efficient tool to diagnose PNL and differentiate it from other causes of NLN. In absence of AFB, the diagnosis of PNL is challenging. In this article, we have satisfactorily evaluated the various hisopthological features and found that endoneurial inflammation, dense fibrosis, and reduction in the number of myelinated nerve fibers are strong supportive indicators of PNL regardless of AFB positivity. PMID:26425006

Pure neuritic leprosy: Resolving diagnostic issues in acid fast bacilli (AFB)-negative nerve biopsies: A single centre experience from South India.

PubMed

Hui, Monalisa; Uppin, Megha S; Challa, Sundaram; Meena, A K; Kaul, Subhash

2015-01-01

Demonstration of lepra bacilli is essential for definite or unequivocal diagnosis of pure neuritic leprosy (PNL) on nerve biopsy. However, nerves always do not show bacilli owing to the changes of previous therapy or due to low bacillary load in tuberculoid forms. In absence of granuloma or lepra bacilli, other morphologic changes in endoneurium and perineurium can be of help in making a probable diagnosis of PNL and treating the patient with multidrug therapy. Forty-six biopsies of PNL were retrospectively reviewed and histologic findings were compared with 25 biopsies of non leprosy neuropathies (NLN) including vasculitic neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP). The distribution of endoneurial infiltrate and fibrosis, perineurial thickening, and myelin abnormalities were compared between PNL and NLN biopsies and analyzed by Chi-square test. Out of 46 PNL casses, 24 (52.17 %) biopsies were negative for acid fast bacilli (AFB). In these cases, the features which favor a diagnosis of AFB-negative PNL were endoneurial infiltrate (51.1%), endoneurial fibrosis (54.2%), perineurial thickening (70.8%), and reduced number of myelinated nerve fibers (75%). Nerve biopsy is an efficient tool to diagnose PNL and differentiate it from other causes of NLN. In absence of AFB, the diagnosis of PNL is challenging. In this article, we have satisfactorily evaluated the various hisopthological features and found that endoneurial inflammation, dense fibrosis, and reduction in the number of myelinated nerve fibers are strong supportive indicators of PNL regardless of AFB positivity.

Bloodstream Infections in Patients With Solid Tumors

PubMed Central

Marín, Mar; Gudiol, Carlota; Garcia-Vidal, Carol; Ardanuy, Carmen; Carratalà, Jordi

2014-01-01

Abstract Current information regarding bloodstream infection (BSI) in patients with solid tumors is scarce. We assessed the epidemiology, antibiotic therapy, and outcomes of BSI in these patients. We also compared patients who died with those who survived to identify risk factors associated with mortality. From January 2006 to July 2012 all episodes of BSI in patients with solid tumors at a cancer center were prospectively recorded and analyzed. A total of 528 episodes of BSI were documented in 489 patients. The most frequent neoplasms were hepatobiliary tumors (19%), followed by lung cancer (18%) and lower gastrointestinal malignancies (16%). Many patients had received corticosteroid therapy (41%), and 15% had neutropenia (<500 neutrophils/μL) at the time of BSI. The most common source of BSI was cholangitis (21%), followed by other abdominal (19.5%) and urinary tract infections (17%). Gram-negative BSI occurred in 55% of cases, mainly due to Escherichia coli (55%), Pseudomonas aeruginosa (18%), and Klebsiella pneumoniae (16%). Among gram-positive BSI (35%), viridans group streptococci were the most frequent causative organisms (22%), followed by Staphylococcus aureus (21%) and Enterococcus species (18%). We identified 61 multidrug-resistant (MDR) organisms (13%), mainly extended-spectrum β-lactamase-producing Enterobacteriaceae (n = 20) and AmpC-producing Enterobacteriaceae (n = 13). The majority of patients with BSI caused by MDR organisms had received antibiotics (70%), and they had been previously hospitalized (61.4%) more frequently than patients with BSI caused by susceptible strains. Inadequate empirical antibiotic therapy was given to 23% of patients, with a higher proportion in those with BSI due to a MDR strain (69%). Early (<48 h) and overall (30 d) case-fatality rates were 7% and 32%, respectively. The overall case-fatality rate was higher among cases caused by MDR organisms (39.3%). The only independent risk factors for the early case-fatality rate were the endogenous source of BSI (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.06–12.02), shock at presentation (OR, 3.63; 95% CI, 1.63–8.09), and corticosteroid therapy (OR, 3.245; 95% CI, 1.43–7.32). The independent risk factors for overall case-fatality rate were the presence of a chronic advanced cancer (OR, 35.39; 95% CI, 2.48–504.91), shock at presentation (OR, 25.84; 95% CI, 3.73–179.0), and corticosteroid therapy (OR, 6.98; 95% CI, 1.61–30.21). BSI in patients with solid tumors occurred mainly among those with hepatobiliary cancer, and cholangitis was the most frequent source; gram-negative bacilli were the most frequent causative agents. MDR organisms were relatively common, particularly in patients who had previously received antibiotics and had been hospitalized; these patients were frequently treated with inadequate empirical antibiotic therapy and had a poorer outcome. The case-fatality rate of patients with solid tumors and BSI was high and was associated with chronic advanced cancer, corticosteroid therapy, and shock at presentation. PMID:24797169

Bloodstream infections in patients with solid tumors: epidemiology, antibiotic therapy, and outcomes in 528 episodes in a single cancer center.

PubMed

Marín, Mar; Gudiol, Carlota; Garcia-Vidal, Carol; Ardanuy, Carmen; Carratalà, Jordi

2014-05-01

Current information regarding bloodstream infection (BSI) in patients with solid tumors is scarce. We assessed the epidemiology, antibiotic therapy, and outcomes of BSI in these patients. We also compared patients who died with those who survived to identify risk factors associated with mortality. From January 2006 to July 2012 all episodes of BSI in patients with solid tumors at a cancer center were prospectively recorded and analyzed. A total of 528 episodes of BSI were documented in 489 patients. The most frequent neoplasms were hepatobiliary tumors (19%), followed by lung cancer (18%) and lower gastrointestinal malignancies (16%). Many patients had received corticosteroid therapy (41%), and 15% had neutropenia (<500 neutrophils/μL) at the time of BSI. The most common source of BSI was cholangitis (21%), followed by other abdominal (19.5%) and urinary tract infections (17%). Gram-negative BSI occurred in 55% of cases, mainly due to Escherichia coli (55%), Pseudomonas aeruginosa (18%), and Klebsiella pneumoniae (16%). Among gram-positive BSI (35%), viridans group streptococci were the most frequent causative organisms (22%), followed by Staphylococcus aureus (21%) and Enterococcus species (18%). We identified 61 multidrug-resistant (MDR) organisms (13%), mainly extended-spectrum β-lactamase-producing Enterobacteriaceae (n = 20) and AmpC-producing Enterobacteriaceae (n = 13). The majority of patients with BSI caused by MDR organisms had received antibiotics (70%), and they had been previously hospitalized (61.4%) more frequently than patients with BSI caused by susceptible strains. Inadequate empirical antibiotic therapy was given to 23% of patients, with a higher proportion in those with BSI due to a MDR strain (69%). Early (<48 h) and overall (30 d) case-fatality rates were 7% and 32%, respectively. The overall case-fatality rate was higher among cases caused by MDR organisms (39.3%). The only independent risk factors for the early case-fatality rate were the endogenous source of BSI (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.06-12.02), shock at presentation (OR, 3.63; 95% CI, 1.63-8.09), and corticosteroid therapy (OR, 3.245; 95% CI, 1.43-7.32). The independent risk factors for overall case-fatality rate were the presence of a chronic advanced cancer (OR, 35.39; 95% CI, 2.48-504.91), shock at presentation (OR, 25.84; 95% CI, 3.73-179.0), and corticosteroid therapy (OR, 6.98; 95% CI, 1.61-30.21).BSI in patients with solid tumors occurred mainly among those with hepatobiliary cancer, and cholangitis was the most frequent source; gram-negative bacilli were the most frequent causative agents. MDR organisms were relatively common, particularly in patients who had previously received antibiotics and had been hospitalized; these patients were frequently treated with inadequate empirical antibiotic therapy and had a poorer outcome. The case-fatality rate of patients with solid tumors and BSI was high and was associated with chronic advanced cancer, corticosteroid therapy, and shock at presentation.

Healthcare-associated infections among pediatric oncology patients in Pakistan: risk factors and outcome.

PubMed

Siddiqui, Naveed-ur-Rehman; Wali, Rabia; Haque, Anwar-ul; Fadoo, Zehra

2012-05-14

Pediatric oncology patients are at increased risk of contracting healthcare-associated infections (HAIs), which are responsible for increased morbidity and mortality rates as well as treatment costs.  This study aimed to identify the frequency of HAIs among pediatric oncology patients and their outcome. Pediatric oncology patients admitted between January 2009 and June 2010 in a pediatric ward at Aga Khan University Hospital, Karachi, Pakistan, who developed HAIs, were analyzed. A total of 90 HAIs were identified in 32 patients in 70 admissions. The HAI rate among pediatric oncology patients was 3.1/100 admission episodes. Bloodstream infections (63 episodes, 90.0%) were the most common, followed by urinary tract infection (two episodes, 2.9%). Gram-positive infections were seen in 54 (60%) patients, followed by Gram-negative infection in 34 (37.8%), and fungi in 2 (2.8%) cases. Coagulase negative staphylococci was the most common Gram-positive and Escherichia coli and Pseudomonas aeruginosa were most common Gram-negative infections. Mortality rate among pediatric oncology patients who developed HAIs was 12.5% (4/32). Total parental nutrition use and length of stay longer than 30 days were the identified risk factors associated with increased mortality among pediatric oncology patients who developed HAIs. We report an HAI rate among pediatric oncology patients of 3.1/100 admission episodes with a mortality rate of 12.5% in Pakistan. Further studies should be done, especially in the developing world, to identify the risk factors associated with increased mortality among pediatric oncology patients so that adequate measures can be taken to reduce the mortality among these patients.

Symptomatic peripheral mycotic aneurysms due to infective endocarditis: a contemporary profile.

PubMed

González, Isabel; Sarriá, Cristina; López, Javier; Vilacosta, Isidre; San Román, Alberto; Olmos, Carmen; Sáez, Carmen; Revilla, Ana; Hernández, Miguel; Caniego, Jose Luis; Fernández, Cristina

2014-01-01

Peripheral mycotic aneurysms (PMAs) are a relatively rare but serious complication of infective endocarditis (IE). We conducted the current study to describe and compare the current epidemiologic, microbiologic, clinical, diagnostic, therapeutic, and prognostic characteristics of patients with symptomatic PMAs (SPMAs). A descriptive, comparative, retrospective observational study was performed in 3 tertiary hospitals, which are reference centers for cardiac surgery. From 922 definite IE episodes collected from 1996 to 2011, 18 patients (1.9%) had SPMAs. Because all SPMAs developed in left-sided IE, we performed a comparative study between 719 episodes of left-sided IE without SPMAs and 18 episodes with SPMAs. We found a higher frequency of intravenous drug abuse, native valve IE, intracranial bleeding, septic emboli, multiple embolisms, and IE diagnostic delay >30 days in patients with SPMAs than in patients without SPMAs. The causal microorganisms were gram-positive cocci (n =10), gram-negative bacilli (n = 2), gram-positive bacilli (n = 3), Bartonella henselae (n = 1), Candida albicans (n = 1), and negative culture (n = 1). The median IE diagnosis delay was 15 days (interquartile range [IQR], 13-33 d) in the case of high-virulence microorganisms versus 45 days (IQR, 30-240 d) in the case of low- to medium-virulence microorganisms. Twelve SPMAs were intracranial and 6 were extracranial. In 10 cases (8 intracranial and 2 extracranial), SPMAs were the initial presentation of IE; the remaining cases developed symptoms during or after finishing parenteral antibiotic treatment. The initial diagnosis of intracranial SPMAs was made by computed tomography (CT) or magnetic resonance imaging in 6 unruptured aneurysms and by angiography in 6 ruptured aneurysms. The initial test in extracranial SPMAs was Doppler ultrasonography in limbs, CT in liver, and coronary angiography in heart. Four (3 intracranial, 1 extracranial) of 7 (6 intracranial, 1 extracranial) patients treated only with antibiotics died. Surgical resection was performed in 7 (3 intracranial, 4 extracranial) and endovascular repair in 4 (3 intracranial, 1 extracranial) patients; all of them survived. In conclusion, we found that SPMAs were a rare complication of IE that developed only in left-sided IE, and especially in native valves. Intracranial hemorrhage, embolism, multiple embolisms, and diagnostic delay of IE were more common in patients with SPMAs. The microbiologic profile was diverse, but microorganisms of low-medium virulence were predominant, and had a greater delayed diagnosis of IE than those caused by microorganisms of high virulence. SPMAs were often the initial presentation of IE. The most common location of SPMAs was intracranial. Noninvasive radiologic imaging techniques were the initial imaging test in intracranial unruptured SPMAs and in most extracranial SPMAs. Surgical and endovascular treatments were safe and effective. Endovascular treatment could be the first line of treatment in selected cases. Mortality was high in those cases treated only with antibiotics.

Bactericidal Effects and Mechanism of Action of Olanexidine Gluconate, a New Antiseptic

PubMed Central

Iwata, Koushi; Nii, Takuya; Nakata, Hikaru; Tsubotani, Yoshie; Inoue, Yasuhide

2015-01-01

Olanexidine gluconate [1-(3,4-dichlorobenzyl)-5-octylbiguanide gluconate] (development code OPB-2045G) is a new monobiguanide compound with bactericidal activity. In this study, we assessed its spectrum of bactericidal activity and mechanism of action. The minimal bactericidal concentrations of the compound for 30-, 60-, and 180-s exposures were determined with the microdilution method using a neutralizer against 320 bacterial strains from culture collections and clinical isolates. Based on the results, the estimated bactericidal olanexidine concentrations with 180-s exposures were 869 μg/ml for Gram-positive cocci (155 strains), 109 μg/ml for Gram-positive bacilli (29 strains), and 434 μg/ml for Gram-negative bacteria (136 strains). Olanexidine was active against a wide range of bacteria, especially Gram-positive cocci, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, and had a spectrum of bactericidal activity comparable to that of commercial antiseptics, such as chlorhexidine and povidone-iodine. In vitro experiments exploring its mechanism of action indicated that olanexidine (i) interacts with the bacterial surface molecules, such as lipopolysaccharide and lipoteichoic acid, (ii) disrupts the cell membranes of liposomes, which are artificial bacterial membrane models, (iii) enhances the membrane permeability of Escherichia coli, (iv) disrupts the membrane integrity of S. aureus, and (v) denatures proteins at relatively high concentrations (≥160 μg/ml). These results indicate that olanexidine probably binds to the cell membrane, disrupts membrane integrity, and its bacteriostatic and bactericidal effects are caused by irreversible leakage of intracellular components. At relatively high concentrations, olanexidine aggregates cells by denaturing proteins. This mechanism differs slightly from that of a similar biguanide compound, chlorhexidine. PMID:25987609

Quantitative and Qualitative Analysis of Bacteria in Er(III) Solution by Thin-Film Magnetopheresis

PubMed Central

Zborowski, Maciej; Tada, Yoko; Malchesky, Paul S.; Hall, Geraldine S.

1993-01-01

Magnetic deposition, quantitation, and identification of bacteria reacting with the paramagnetic trivalent lanthanide ion, Er3+, was evaluated. The magnetic deposition method was dubbed thin-film magnetopheresis. The optimization of the magnetic deposition protocol was accomplished with Escherichia coli as a model organism in 150 mM NaCl and 5 mM ErCl3 solution. Three gram-positive bacteria, Staphylococcus epidermidis, Staphylococcus saprophyticus, and Enterococcus faecalis, and four gram-negative bacteria, E. coli, Pseudomonas aeruginosa, Proteus mirabilis, and Klebsiella pneumoniae, were subsequently investigated. Quantitative analysis consisted of the microscopic cell count and a scattered-light scanning of the magnetically deposited material aided by the computer data acquisition system. Qualitative analysis consisted of Gram stain differentiation and fluorescein isothiocyanate staining in combination with selected antisera against specific types of bacteria on the solid substrate. The magnetic deposition protocol allowed quantitative detection of E. coli down to the concentration of 105 CFU ml-1, significant in clinical diagnosis applications such as urinary tract infections. Er3+ did not interfere with the typical appearance of the Gram-stained bacteria nor with the antigen recognition by the antibody in the immunohistological evaluations. Indirect antiserum-fluorescein isothiocyanate labelling correctly revealed the presence of E. faecalis and P. aeruginosa in the magnetically deposited material obtained from the mixture of these two bacterial species. On average, the reaction of gram-positive organisms was significantly stronger to the magnetic field in the presence of Er3+ than the reaction of gram-negative organisms. The thin-film magnetophoresis offers promise as a rapid method for quantitative and qualitative analysis of bacteria in solutions such as urine or environmental water. Images PMID:16348916

Automated detection of tuberculosis on sputum smeared slides using stepwise classification

NASA Astrophysics Data System (ADS)

Divekar, Ajay; Pangilinan, Corina; Coetzee, Gerrit; Sondh, Tarlochan; Lure, Fleming Y. M.; Kennedy, Sean

2012-03-01

Routine visual slide screening for identification of tuberculosis (TB) bacilli in stained sputum slides under microscope system is a tedious labor-intensive task and can miss up to 50% of TB. Based on the Shannon cofactor expansion on Boolean function for classification, a stepwise classification (SWC) algorithm is developed to remove different types of false positives, one type at a time, and to increase the detection of TB bacilli at different concentrations. Both bacilli and non-bacilli objects are first analyzed and classified into several different categories including scanty positive, high concentration positive, and several non-bacilli categories: small bright objects, beaded, dim elongated objects, etc. The morphological and contrast features are extracted based on aprior clinical knowledge. The SWC is composed of several individual classifiers. Individual classifier to increase the bacilli counts utilizes an adaptive algorithm based on a microbiologist's statistical heuristic decision process. Individual classifier to reduce false positive is developed through minimization from a binary decision tree to classify different types of true and false positive based on feature vectors. Finally, the detection algorithm is was tested on 102 independent confirmed negative and 74 positive cases. A multi-class task analysis shows high accordance rate for negative, scanty, and high-concentration as 88.24%, 56.00%, and 97.96%, respectively. A binary-class task analysis using a receiver operating characteristics method with the area under the curve (Az) is also utilized to analyze the performance of this detection algorithm, showing the superior detection performance on the high-concentration cases (Az=0.913) and cases mixed with high-concentration and scanty cases (Az=0.878).

Nested polymerase chain reaction (PCR) targeting 16S rDNA for bacterial identification in empyema.

PubMed

Prasad, Rajniti; Kumari, Chhaya; Das, B K; Nath, Gopal

2014-05-01

Empyema in children causes significant morbidity and mortality. However, identification of organisms is a major concern. To detect bacterial pathogens in pus specimens of children with empyema by 16S rDNA nested polymerase chain reaction (PCR) and correlate it with culture and sensitivity. Sixty-six children admitted to the paediatric ward with a diagnosis of empyema were enrolled prospectively. Aspirated pus was subjected to cytochemical examination, culture and sensitivity, and nested PCR targeting 16S rDNA using a universal eubacterial primer. Mean (SD) age was 5·8 (1·8) years (range 1-13). Analysis of aspirated pus demonstrated total leucocyte count >1000×10(6)/L, elevated protein (≧20 g/L) and decreased glucose (≤2·2 mmol/L) in 80·3%, 98·5% and 100%, respectively. Gram-positive cocci were detected in 29 (43·9%) and Gram-negative bacilli in two patients. Nested PCR for the presence of bacterial pathogens was positive in 50·0%, compared with 36·3% for culture. 16S rDNA PCR improves rates of detection of bacteria in pleural fluid, and can detect bacterial species in a single assay as well as identifying unusual and unexpected causal agents.

Isolation and analysis of bacteria with antimicrobial activities from the marine sponge Haliclona simulans collected from Irish waters.

PubMed

Kennedy, Jonathan; Baker, Paul; Piper, Clare; Cotter, Paul D; Walsh, Marcella; Mooij, Marlies J; Bourke, Marie B; Rea, Mary C; O'Connor, Paula M; Ross, R Paul; Hill, Colin; O'Gara, Fergal; Marchesi, Julian R; Dobson, Alan D W

2009-01-01

Samples of the marine sponge Haliclona simulans were collected from Irish coastal waters, and bacteria were isolated from these samples. Phylogenetic analyses of the cultured isolates showed that four different bacterial phyla were represented; Bacteriodetes, Actinobacteria, Proteobacteria, and Firmicutes. The sponge bacterial isolates were assayed for the production of antimicrobial substances, and biological activities against Gram-positive and Gram-negative bacteria and fungi were demonstrated, with 50% of isolates showing antimicrobial activity against at least one of the test strains. Further testing showed that the antimicrobial activities extended to the important pathogens Pseudomonas aeruginosa, Clostridium difficile, multi-drug-resistant Staphylococcus aureus, and pathogenic yeast strains. The Actinomycetes were numerically the most abundant producers of antimicrobial activities, although activities were also noted from Bacilli and Pseudovibrio isolates. Surveys for the presence of potential antibiotic encoding polyketide synthase and nonribosomal peptide synthetase genes also revealed that genes for the biosynthesis of these secondary metabolites were present in most bacterial phyla but were particularly prevalent among the Actinobacteria and Proteobacteria. This study demonstrates that the culturable fraction of bacteria from the sponge H. simulans is diverse and appears to possess much potential as a source for the discovery of new medically relevant biological active agents.

Microbiological characterization of the biological treatment of aircraft paint stripping wastewater.

PubMed

Arquiaga, M C; Canter, L W; Robertson, J M

1995-01-01

Research on the treatment of potentially toxic wastewater produced at six US Navy aircraft paint stripping facilities has been conducted. The composition of the wastewater treated consisted of methylene chloride and phenol in concentrations of about 5000 and 1800 mg/l, respectively, and other organic compounds in a total concentration of 2200 mg/l. Biological treatment is an important means by which toxic or hazardous organic compounds can be economically converted to less noxious materials. Engineering studies conducted in the laboratory with activated sludge reactors and rotating biological contactors (RBC) demonstrated that both suspended and attached growths can be effective biological methods to treat this paint stripping wastewater when blended with domestic wastewater up to about 50% by volume. These studies were complemented with analyses of the bacterial communities inhabiting the treatment systems. The number and the genera of the microorganisms present in the blended wastewater, as well as their ability to biodegrade the potentially toxic organics were studied. The results indicate that paint stripping wastewater is able to support large bacterial populations consisting of various gram-negative rods and coccibacilli and a few gram-positive bacilli. Members of the genera Pseudomonas and Bacillus are suspected to play an important role in initiating the biodegradation process.

[Multidrug resistance E-ESKAPE strains isolated from blood cultures in patients with cancer].

PubMed

Velázquez-Acosta, Consuelo; Cornejo-Juárez, Patricia; Volkow-Fernández, Patricia

2018-01-01

To describe the trend of multidrug resistant (MDR) strains isolated from blood in patients with cancer from 2005 to 2015. 33 127 blood cultures were processed by retrospective analysis. Identification and antimicrobial sensitivity were performed through automated methods: WaLK away (Siemens Labora- tory Diagnostics) and BD Phoenix (Becton, Dickinson and Company). Resistant strains were determined according to the minimum inhibitory concentration, following the parameters of the Clinical and Laboratory Standards Institute (CLSI). Of 6 397 isolates, 5 604 (16.9%) were positive; 3 732 (58.4%) Gram- bacilli; 2 355 (36.9%) Gram+ cocci; 179 (2.7%) yeasts, and 126 (1.9%) Gram+ bacilli. Escherichia coli (n=1 591, 24.5%) was the most frequent bacteria, with 652 (41%) strains being extended-spectrum beta-lactamases producers (ESBL); of Enterococcus faecium (n=143, 2.1%), 45 (31.5%) were vancomycin resistant; of Staphylococcus aureus (n=571, 8.7%), 121 (21.2%) methicillin resistant (MRSA); of Klebsiella pneumoniae (n=367, 5.6%), 41 (11.2%) ESBL; of Acinetobacter baumanii (n=96, 1.4%), 23 (24%) MDR, and of Pseudomonas aeruginosa (n=384, 5.6%), 43 (11.2%) MDR. MDR strains were significantly more frequent in patients with hematological malignancies, compared to those with solid tumors: MRSA (OR=4.48, 95%CI 2.9-6.8), ESBL E. coli(OR=1.3, 95%CI 1.10-1.65) and MDR Acinetobacter baumanii (OR=3.2, 95%CI 1.2-8.3). We observed significantly higher isolations of E-ESPAKE MDR strains in patients with hematological malignancies.

Genomic determinants of sporulation in Bacilli and Clostridia: towards the minimal set of sporulation-specific genes

PubMed Central

Galperin, Michael Y; Mekhedov, Sergei L; Puigbo, Pere; Smirnov, Sergey; Wolf, Yuri I; Rigden, Daniel J

2012-01-01

Three classes of low-G+C Gram-positive bacteria (Firmicutes), Bacilli, Clostridia and Negativicutes, include numerous members that are capable of producing heat-resistant endospores. Spore-forming firmicutes include many environmentally important organisms, such as insect pathogens and cellulose-degrading industrial strains, as well as human pathogens responsible for such diseases as anthrax, botulism, gas gangrene and tetanus. In the best-studied model organism Bacillus subtilis, sporulation involves over 500 genes, many of which are conserved among other bacilli and clostridia. This work aimed to define the genomic requirements for sporulation through an analysis of the presence of sporulation genes in various firmicutes, including those with smaller genomes than B. subtilis. Cultivable spore-formers were found to have genomes larger than 2300 kb and encompass over 2150 protein-coding genes of which 60 are orthologues of genes that are apparently essential for sporulation in B. subtilis. Clostridial spore-formers lack, among others, spoIIB, sda, spoVID and safA genes and have non-orthologous displacements of spoIIQ and spoIVFA, suggesting substantial differences between bacilli and clostridia in the engulfment and spore coat formation steps. Many B. subtilis sporulation genes, particularly those encoding small acid-soluble spore proteins and spore coat proteins, were found only in the family Bacillaceae, or even in a subset of Bacillus spp. Phylogenetic profiles of sporulation genes, compiled in this work, confirm the presence of a common sporulation gene core, but also illuminate the diversity of the sporulation processes within various lineages. These profiles should help further experimental studies of uncharacterized widespread sporulation genes, which would ultimately allow delineation of the minimal set(s) of sporulation-specific genes in Bacilli and Clostridia. PMID:22882546

Chlamydia pneumoniae Infection Among Basic Underwater Demolition/SEAL (BUD/S) Trainees, Coronado, California, July 2008

DTIC Science & Technology

2011-03-01

including Streptococcus pneumoniae, Chlamydophila pneu- moniae, Mycoplasma pneumoniae, Legionella pneumophila, and Bordetella pertussis . 3 CAP...CAP. 15 Additionally, radiological fi ndings have a limited capacity to differentiate the etiologic agents of CAP. 16 Because treatment modalities...and gram-positive bacilli and have been used in the treatment of atyp- ical pneumonias including M pneumoniae and C pneumoniae . 26 The need to

Impact of a Stewardship-Initiated Restriction on Empirical Use of Ciprofloxacin on Nonsusceptibility of Escherichia coli Urinary Isolates to Ciprofloxacin.

PubMed

O'Brien, Kristen A; Zhang, Jingwen; Mauldin, Patrick D; Gomez, Juanmanuel; Hurst, John M; Sean Boger, M; Bosso, John A

2015-05-01

To evaluate the impact of a stewardship-initiated restriction on empirical use of ciprofloxacin on the nonsusceptibility of Escherichia coli urinary isolates to ciprofloxacin over time while controlling for the use of other key antibiotics with gram-negative activity. Retrospective single-center study. Large tertiary and quaternary care academic medical center. Of 3714 E. coli urinary isolates. The susceptibilities of the E. coli urinary isolates to ciprofloxacin, ceftriaxone, cefepime, piperacillin-tazobactam, meropenem, trimethoprim-sulfamethoxazole, and nitrofurantoin obtained over a 7-year period (January 1, 2006-December 31, 2012) from adult inpatients were evaluated for potential relationships with antibiotic use over time by using multiple variable regression analysis. After introduction of the restriction on empirical use of ciprofloxacin in the first quarter of 2011, ciprofloxacin use declined from 141.1-39.8 defined daily doses/1000 patient-days, and the percentage of E. coli isolates that were not susceptible to ciprofloxacin decreased from 41.5-32.8%. With all antibiotics evaluated included in the model, no apparent relationships were found between the percentage of E. coli isolates nonsusceptible to ciprofloxacin and antibiotic use. However, when nonsignificant variables were eliminated (p>0.20), ciprofloxacin use was found to be positively associated with the percentage of E. coli isolates nonsusceptible to ciprofloxacin (p=0.037), whereas ceftriaxone use was negatively associated (p=0.045). The restriction and subsequent reduction of ciprofloxacin use was found to have a positive effect on the susceptibility of E. coli urinary isolates to ciprofloxacin. © 2015 Pharmacotherapy Publications, Inc.

Fosfomycin versus meropenem in bacteraemic urinary tract infections caused by extended-spectrum β-lactamase-producing Escherichia coli (FOREST): study protocol for an investigator-driven randomised controlled trial.

PubMed

Rosso-Fernández, Clara; Sojo-Dorado, Jesús; Barriga, Angel; Lavín-Alconero, Lucía; Palacios, Zaira; López-Hernández, Inmaculada; Merino, Vicente; Camean, Manuel; Pascual, Alvaro; Rodríguez-Baño, Jesús

2015-03-31

Finding therapeutic alternatives to carbapenems in infections caused by extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) is imperative. Although fosfomycin was discovered more than 40 years ago, it was not investigated in accordance with current standards and so is not used in clinical practice except in desperate situations. It is one of the so-called neglected antibiotics of high potential interest for the future. The main objective of this project is to demonstrate the clinical non-inferiority of intravenous fosfomycin with regard to meropenem for treating bacteraemic urinary tract infections (UTI) caused by ESBL-EC. This is a 'real practice' multicentre, open-label, phase III randomised controlled trial, designed to compare the clinical and microbiological efficacy, and safety of intravenous fosfomycin (4 g/6 h) and meropenem (1 g/8 h) as targeted therapy for this infection; a change to oral therapy is permitted after 5 days in both arms, in accordance with predetermined options. The study design follows the latest recommendations for designing trials investigating new options for multidrug-resistant bacteria. Secondary objectives include the study of fosfomycin concentrations in plasma and the impact of both drugs on intestinal colonisation by multidrug-resistant Gram-negative bacilli. Ethical approval was obtained from the Andalusian Coordinating Institutional Review Board (IRB) for Biomedical Research (Referral Ethics Committee), which obtained approval from the local ethics committees at all participating sites in Spain (22 sites). Data will be presented at international conferences and published in peer-reviewed journals. This project is proposed as an initial step in the investigation of an orphan antimicrobial of low cost with high potential as a therapeutic alternative in common infections such as UTI in selected patients. These results may have a major impact on the use of antibiotics and the development of new projects with this drug, whether as monotherapy or combination therapy. NCT02142751. EudraCT no: 2013-002922-21. Protocol V.1.1 dated 14 March 2014. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Triton Hodge Test: Improved Protocol for Modified Hodge Test for Enhanced Detection of NDM and Other Carbapenemase Producers.

PubMed

Pasteran, Fernando; Gonzalez, Lisandro J; Albornoz, Ezequiel; Bahr, Guillermo; Vila, Alejandro J; Corso, Alejandra

2016-03-01

Accurate detection of carbapenemase-producing Gram-negative bacilli is of utmost importance for the control of nosocomial spread and the initiation of appropriate antimicrobial therapy. The modified Hodge test (MHT), a carbapenem inactivation assay, has shown poor sensitivity in detecting the worldwide spread of New Delhi metallo-β-lactamase (NDM). Recent studies demonstrated that NDM is a lipoprotein anchored to the outer membrane in Gram-negative bacteria, unlike all other known carbapenemases. Here we report that membrane anchoring of β-lactamases precludes detection of carbapenemase activity by the MHT. We also show that this limitation can be overcome by the addition of Triton X-100 during the test, which allows detection of NDM. We propose an improved version of the assay, called the Triton Hodge test (THT), which allows detection of membrane-bound carbapenemases with the addition of this nonionic surfactant. This test was challenged with a panel of 185 clinical isolates (145 carrying known carbapenemase-encoding genes and 40 carbapenemase nonproducers). The THT displayed test sensitivity of >90% against NDM-producing clinical isolates, while improving performance against other carbapenemases. Ertapenem provided the highest sensitivity (97 to 100%, depending on the type of carbapenemase), followed by meropenem (92.5 to 100%). Test specificity was not affected by the addition of Triton (87.5% and 92.5% with ertapenem and meropenem, respectively). This simple inexpensive test confers a large improvement to the sensitivity of the MHT for the detection of NDM and other carbapenemases. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The First Report of Drug Resistant Bacteria Isolated from the Brown-Banded Cockroach, Supella longipalpa, in Ahvaz, South-western Iran

PubMed Central

Vazirianzadeh, Babak; Dehghani, Rouhullah; Mehdinejad, Manijeh; Sharififard, Mona; Nasirabadi, Nersi

2014-01-01

Background The brown-banded cockroach, Supella longipalpa is known as a carrier of pathogenic bacteria in urban environments, but its role is not well documented regarding the carriage of antibiotic-resistant pathogenic bacteria in Iran. The aim of this study was to determine the resistance bacteria isolated from the brown-banded cockroach in Ahvaz, south west of Iran. Methods: Totally 39 cockroaches were collected from kitchen area of houses and identified. All specimens were cultured to isolate the bacterial agents on blood agar and MacConky agar media. The microorganisms were identified using necessary differential and biochemical tests. Antimicrobial susceptibility tests were performed for isolated organisms by Kirby-Bauer’s disk diffusion according to NCLI guideline, using 18 antibiotics. Results: From the 39 collected S. langipalpa, 179 bacterial agents were isolated, 92 of alimentary ducts and 87 of external body surfaces. Isolated bacteria from cockroaches were identified as Enterobacter spp., Klebsiella spp., Citrobacter spp., Escherichia coli, Salmonella spp., Proteus spp., coagulase negative staphylococci, Serratia marcescens, Staphylococcus aureus, and Bacillus species. The pattern resistance rates were determined for gram negative bacilli and gram positive cocci regarding 18 antibiotics. Conclusion: The brown-banded cockroach can be involved in the spread of drug resistant bacteria and increases the possibility of contacting human environment to drug resistant bacteria. Therefore, the potential of removing this insect should be improved. This is the first original report of drug resistant bacteria isolated from the brown-banded cockroach of Iran. PMID:25629065

Draft genome sequence of a GES-5-producing Serratia marcescens isolated in southern Brazil.

PubMed

Nodari, Carolina Silva; Siebert, Marina; Matte, Ursula da Silveira; Barth, Afonso Luís

Serratia marcescens is a Gram-negative rod intrinsically resistant to polymyxins and usually associated with wound, respiratory and urinary tract infections. The whole genome of the first GES-5-producing S. marcescens isolated from a Brazilian patient was sequenced using Ion Torrent PGM System. Besides bla GES-5 , we were able to identify genes encoding for other β-lactamases, for aminoglycoside modifying enzymes and for an efflux pump to tetracyclines. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Identification of mycobacterium tuberculosis in sputum smear slide using automatic scanning microscope

NASA Astrophysics Data System (ADS)

Rulaningtyas, Riries; Suksmono, Andriyan B.; Mengko, Tati L. R.; Saptawati, Putri

2015-04-01

Sputum smear observation has an important role in tuberculosis (TB) disease diagnosis, because it needs accurate identification to avoid high errors diagnosis. In development countries, sputum smear slide observation is commonly done with conventional light microscope from Ziehl-Neelsen stained tissue and it doesn't need high cost to maintain the microscope. The clinicians do manual screening process for sputum smear slide which is time consuming and needs highly training to detect the presence of TB bacilli (mycobacterium tuberculosis) accurately, especially for negative slide and slide with less number of TB bacilli. For helping the clinicians, we propose automatic scanning microscope with automatic identification of TB bacilli. The designed system modified the field movement of light microscope with stepper motor which was controlled by microcontroller. Every sputum smear field was captured by camera. After that some image processing techniques were done for the sputum smear images. The color threshold was used for background subtraction with hue canal in HSV color space. Sobel edge detection algorithm was used for TB bacilli image segmentation. We used feature extraction based on shape for bacilli analyzing and then neural network classified TB bacilli or not. The results indicated identification of TB bacilli that we have done worked well and detected TB bacilli accurately in sputum smear slide with normal staining, but not worked well in over staining and less staining tissue slide. However, overall the designed system can help the clinicians in sputum smear observation becomes more easily.

Office diagnosis of asymptomatic bacteriuria in pregnant women.

PubMed

Van Dorsten, J P; Bannister, E R

1986-10-01

Diagnosis and treatment of asymptomatic bacteriuria in pregnant patients can virtually eliminate pyelonephritis, the most common medical cause for antepartum hospitalization. However, the ever-increasing cost of the urine culture has led most clinicians away from routine urine screening. Uricult dip-slide paddles provide an inexpensive, efficient way to screen urine. Clean-catch urine specimens were obtained from 544 consecutive asymptomatic pregnant patients seen in the outpatient obstetric clinic at the Medical University of South Carolina. Specimens were analyzed by both traditional culture techniques and the Uricult dip-slide paddles. By comparison, the Uricult test detected 55 of the 56 significant gram-negative urinary pathogens found by culture. Detection of potential gram-positive pathogens is more difficult. A scheme is proposed that allows reliable, inexpensive surveillance in all pregnant patients. Hopefully, this algorithm will rekindle the obstetrician's interest in urine screening.

Cross-contamination potential of saliva ejectors used in dentistry.

PubMed

Barbeau, J; ten Bokum, L; Gauthier, C; Prévost, A P

1998-12-01

It has been postulated that evacuation systems used in dentistry could be a source of cross-contamination between patients through backflow of bacteria dislodged from the saliva ejector tubings. The bacterial microflora associated with these systems was characterized using transmission electron microscopy (TEM) and microbiological cultures. The potential for backflow was investigated by a study of pressure differentials in evacuation system tubing and by the presence of bacteria in backflow samples. Evacuation lines were coated with microbial biofilms in which microcolonies of Gram-positive cocci and Gram-negative bacilli predominated, embedded in an extensive polysaccharide matrix. Most bacteria were metabolically active. Occasionally, buccal material such as collagen, fibrin and eukaryotic cell debris was observed. In other experiments, flow reversal was detected several times during saliva ejector use though each of these events was brief (less than 0.1 s). Aspiration of saliva, or occlusion of the mouthpiece opening by the oral mucosa, were the major factors leading to backflow episodes. Bacteria associated with backflow were found in almost 25% assays, with counts ranging from 1-300 cfu/occurrence. The majority of the bacteria isolated from biofilm or backflow samples were staphylococci, micrococci and non-fermentive Gram-negative rods. Pathogens such as Pseudomonas aeruginosa and Staphylococcus aureus were also isolated from backflow fluids. No oral streptococci could be recovered from biofilms in the tubing beyond 15 min from the last saliva ejector use however, suggesting that these species did not survive in the biofilms. These data suggest, although without direct proof of cross-contamination, the possible existence of an infectious risk associated with oral evacuation systems, as potential pathogens may be shed from tubing biofilms following backflow. Even if the risk of cross-contamination between patients is considered to be low, the necessity for regular disinfection of these systems must be stressed, since biofilms can serve as a reservoir for pathogens or harbor potentially infectious material.

Local resistance patterns to antimicrobials in internal medicine: a focused report from the REGIMEN (REGistro Infezioni in MEdicina INterna) study.

PubMed

Cei, Marco; Pardelli, Riccardo; Sani, Spartaco; Mumoli, Nicola

2014-02-01

The treatment for infections in hospitalized patients can be summarized in the timely start of empirical therapy, followed by adjustment on the basis of isolates and microbial susceptibilities. Initial therapy may be based on international guidelines. However, to know local frequencies of bacterial and fungal strains together with patterns of drug resistance should be a better approach to therapy. REGIMEN is a retrospective observational study of all consecutive recorded bacterial and fungal isolates, collected between October 2009 and August 2011 from patients admitted in a 53-bedded ward of internal medicine of a non-teaching Italian hospital. We investigated type of samples and of microorganisms, patterns of susceptibility and resistance to antibiotics, and in-hospital mortality. A total of 504 samples were examined (244 from urine, 189 from blood and 71 from skin and various exudates). Participants were old (mean age, 83 years), and so overall mortality was high (20 %). There were high frequencies of drug resistance; only 27.9 % of urinary gram-negatives and 52.6 % of blood gram-negatives were susceptible to levofloxacin. Susceptibility profiles compatible with the presence of extended-spectrum beta-lactamases were present in 64.2 % of gram-negative strains, and 10.1 % were also resistant to carbapenems. ESKAPE organisms account for a third of all bacterial infections. Local patterns of drug resistance should influence empirical antibiotic therapy for patients admitted in internal medicine wards, where mortality is high.

Diagnosis of nosocomial pneumonia in intubated, intensive care unit patients.

PubMed

Salata, R A; Lederman, M M; Shlaes, D M; Jacobs, M R; Eckstein, E; Tweardy, D; Toossi, Z; Chmielewski, R; Marino, J; King, C H

1987-02-01

The clinical distinction between bacterial colonization of the tracheobronchial tree and nosocomial pneumonia is difficult, especially in intubated patients. We studied 51 intubated, intensive care unit patients prospectively by serial examinations of tracheal aspirates for elastin fibers, graded Gram's stains, and quantitative bacterial cultures in conjunction with clinical and radiologic observations in an attempt to develop criteria for the early detection of pulmonary infection. Patients with infection had new or progressive pulmonary infiltrates plus 1 of the following: positive blood culture results, radiographic evidence of cavitation, or histologic evidence of pneumonia, or 2 or more of the following: new fever, new leukocytosis, or grossly purulent tracheal aspirates. Twenty-one patients developed infection, 22 remained colonized, and 8 had an uncertain status. Infiltrates developed in 34 patients (21 infected, 8 colonized, 5 uncertain status). Gram-negative bacilli were most commonly isolated and were more frequent in infected patients (81 versus 47%, p less than 0.05); Pseudomonas aeruginosa and Serratia marcescens were most often associated with infection. No differences were observed between infected and colonized patients in demographic features, smoking history, underlying disease, previous antibiotic therapy, days in hospital before intubation, preexisting pneumonia upon intubation, or highest temperature or leukocyte count during course. By univariate analysis, infected patients had a longer duration of intubation (p less than 0.05), higher Gram's stain grading for neutrophils (p less than 0.05) or bacteria (p less than 0.005), higher bacterial colony counts (p less than 0.05), and more frequent detection of elastin fibers in tracheal aspirates (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of antibiotic use on antimicrobial antibiotic resistance and late-onset neonatal infections over 25 years in an Australian tertiary neonatal unit.

PubMed

Carr, David; Barnes, Elizabeth Helen; Gordon, Adrienne; Isaacs, David

2017-05-01

Antibiotic resistance is a worldwide problem. We describe 25 years of responsible antibiotic use in a tertiary neonatal unit. Data on neonatal infections and antibiotic use were collected prospectively from 1990 to 2014 at a single tertiary Sydney neonatal intensive care unit attached to a maternity unit. There are approximately 5500 deliveries and 900 nursery admissions per year. The mean annual rate of late-onset sepsis was 1.64 episodes per 100 admissions. The mean number of late-onset sepsis episodes per admission to the neonatal unit decreased by 4.0% per year (95% CI 2.6% to 5.4%; p<0.0001) and occurred particularly in infants born weighing <1500 g. No infants with negative cultures relapsed with sepsis when antibiotics were stopped after 48-72 hours. Antibiotic use decreased with time. The proportion of colonising methicillin-resistant Staphylococcus aureus isolates decreased by 7.4% per year (95% CI 0.2% to 14.1%; p=0.043). The proportion of colonising Gram-negative bacilli isolates resistant to either third-generation cephalosporins or gentamicin increased by 2.9% per year (95% CI 1.0% to 4.9%; p=0.0035). Most were cephalosporin-resistant; gentamicin resistance was rare. An average of one baby per year died from late-onset sepsis, the rate not varying significantly over time. The mortality from episodes of late-onset sepsis was 25 of 332 (7.5%). Stopping antibiotics after 2-3 days if neonatal systemic cultures are negative is safe. However, it does not prevent the emergence of cephalosporin-resistant Gram-negative organisms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Urinary tract infection diagnosis and response to antibiotics using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Kyriakides, Alexandros; Hadjigeorgiou, Katerina; Pitris, Constantinos

2009-02-01

Urinary tract infection diagnosis and antibiogram require a 48 hour waiting period using conventional methods. This results in ineffective treatments, increased costs and most importantly in increased resistance to antibiotics. In this work, a novel method for classifying bacteria and determining their sensitivity to an antibiotic using Raman spectroscopy is described. Raman spectra of three species of gram negative Enterobacteria, most commonly responsible for urinary tract infections, were collected. The study included 25 samples each of E.coli, Klebsiella p. and Proteus spp. A novel algorithm based on spectral ratios followed by discriminant analysis resulted in classification with over 94% accuracy. Sensitivity and specificity for the three types of bacteria ranged from 88-100%. For the development of an antibiogram, bacterial samples were treated with the antibiotic ciprofloxacin to which they were all sensitive. Sensitivity to the antibiotic was evident after analysis of the Raman signatures of bacteria treated or not treated with this antibiotic as early as two hours after exposure. This technique can lead to the development of new technology for urinary tract infection diagnosis and antibiogram with same day results, bypassing urine cultures and avoiding all undesirable consequences of current practice.

[Urinary tract infections--pediatric urologist point of view].

PubMed

Baka-Ostrowska, Małgorzata

2008-01-01

Urinary tract infections (UTI) could present with different clinical forms dependent on intensity and localization of infection and child's age. The symptoms could be non specific in children. Condition that provoke to urinary stasis, especially voiding dysfunction is the favourable factor for UTI appearance. Gram-negative enteric bacteria is the most common pathogen. Urine culture is the basic investigation that allow to identify pathogen and its drug sensitiveness but simultaneous urinalysis is necessary to recognize the inflammation of urinary organs. In addition, the number of leukocytes gives an idea about inflammation intensity. Ultrasonographic (USG) scan is necessary to examine urostasis. DMSA study performed during febrile UTI allow to identify children with acute pyelonephritis and when repeated 6 months later - those with renal scars. A normal USG and DMSA scan during infection makes voiding cystourethrography (VCU) unnecessary in the primary examination. The presence of vesicoureteric reflux (VUR) not always predispose children to renal lesions. Early and appropriate treatment of UTI, especially during the first 24 hours, diminishes the likelihood of renal involvement during the acute phase of infection but does not prevent scar formation. The proper hygiene of the urethral meatus, voiding and drinking habits and preventing of constipation are crucial in UTI prophylaxis.

[Monitoring nosocomial infections using a laboratory-based system].

PubMed

Montella, F; Gallo, S; Leacche, G; Macchia, G

1998-01-01

In this paper we report the results of a nosocomial infections surveillance system "Laboratory Based". The system started in August 1995 at San Giovanni Hospital, Rome. All the specimens sent to the Microbiology Laboratory have been registered using a computerized input form. 12,204 forms, attributable to patients between 0 and 97 years (median 43 years) resulted evaluable. The global rate of incidence of nosocomial infection was, in the study period, 16 per one thousand person/day. The rate of incidence, when stratified for the medical, surgical and emergency boards, was, respectively, 19 per one thousand person/day in the medical facilities, 15 per one thousand person/day in surgical and 17 per one thousand person/year in emergency facilities. The nosocomial infections incidence correlated well with the age of the patients and the time of bed stay. The bulk of infections were localized to the respiratory apparatus. Localization to urinary apparatus and sepsis follow. The isolated microbes were (38%) gram-negative microbes; the 38% of the isolates are gram-negative microbes and the 24% are Mycetes. Our data validate the surveillance system in a great hospital of Rome metropolitan area.

Longitudinal surveillance on antibiogram of important Gram-positive pathogens in Southern China, 2001 to 2015.

PubMed

Xu, Zhenbo; Xie, Jinhong; Peters, Brian M; Li, Bing; Li, Lin; Yu, Guangchao; Shirtliff, Mark E

2017-02-01

A longitudinal surveillance aimed to investigate the antibiogram of three genus of important Gram-positive pathogens in Southern China during 2001-2015. A total of 3849 Staphylococcus, Enterococcus and Streptococcus strains were isolated from Southern China during 2001-2015. Bacteria identification was performed by colony morphology, Gram staining, the API commercial kit and the Vitek 2 automated system. Antimicrobial susceptibility testing was determined by disk diffusion method and MIC method. As sampling site was concerned, 51.4% of Staphylococcus strains were isolated from sputum, whereas urinary tract remained the dominant infection site among Enterococcus and Streptococcus. According to the antimicrobial susceptibility, three genus of important Gram-positive pathogens showed high resistance against erythromycin, tetracycline, ciprofloxacin and clindamycin. Resistance rates to penicillins (penicillin, oxacillin, ampicillin) were high as well, with the exception of E. faecalis and Streptococcus. Overall, resistance rates against methicillin (oxacillin) were 63.2% in S. aureus and 76.2% in coagulase-negative Staphylococcus (CNS), along with continuous increases during the study. VRSA and vancomycin-resistant coagulase-negative Staphylococcus only appeared in 2011-2015. Sight decline was obtained for the vancomycin resistance of E. faecalis, while vancomycin-resistant E. faecium only appeared in 2011-2015, with its intermediate rate decreasing. Significant decrease in penicillin-resistant Streptococcus pneumonia (PRSP) was observed during studied period. Glycopeptide antibiotic remained highly effective to Staphylococcus, Enterococcus and Streptococcus (resistance rates <5%). Despite decline obtained for some antibiotic agents resistance during 2001-2015, antimicrobial resistance among Gram-positive pathogens still remained high in Southern China. This study may aid in the guidance for appropriate therapeutic strategy of infections caused by nosocomial pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Incidence, Causes, and Impact of In-Hospital Infections After Transcatheter Aortic Valve Implantation.

PubMed

Tirado-Conte, Gabriela; Freitas-Ferraz, Afonso B; Nombela-Franco, Luis; Jimenez-Quevedo, Pilar; Biagioni, Corina; Cuadrado, Ana; Nuñez-Gil, Ivan; Salinas, Pablo; Gonzalo, Nieves; Ferrera, Carlos; Vivas, David; Higueras, Javier; Viana-Tejedor, Ana; Perez-Vizcayno, Maria Jose; Vilacosta, Isidre; Escaned, Javier; Fernandez-Ortiz, Antonio; Macaya, Carlos

2016-08-01

In-hospital infections (IHI) are one of the most common and serious problems after invasive procedures. Transcatheter aortic valve implantation (TAVI) is an increasingly used alternative to surgery in patients with severe symptomatic aortic stenosis. The aim of this study was to determine the incidence, origin, risk factors, and clinical outcomes of IHI after TAVI. A total of 303 consecutive patients with severe aortic stenosis who underwent transfemoral TAVI were included and followed during a median time of 21 months. We examined the occurrence, types, origin, and timing of infections during hospital stay as well as short- and long-term clinical outcomes according to the occurrence of IHI. A total of 51 patients (17%; 62 infectious episodes) experienced IHI after TAVI. Respiratory and urinary tract infections were the most frequent type of infections (44% and 34%, respectively), followed by surgical site infection (8%) and bloodstream infection (5%). Positive cultures were obtained in 74% of the samples, of which 65% were gram-negative bacilli. Modifiable factors such as bleeding (p = 0.005) and length of coronary care unit stay (p <0.001) were independently associated with an increased infection risk. Patients with IHI had a longer hospital stay (14 vs 6 days, p <0.001), an increased mortality (hazard ratio 2.48, 95% CI 1.45 to 4.23) and readmission rate (hazard ratio 2.0, 95% CI 1.27 to 3.14) during the follow-up. In conclusion, IHI is a frequent complication after TAVI with a significant impact on short- and long-term clinical outcomes. The most important risk factors associated with the development of this complication were modifiable periprocedural aspects. These results underline the importance to implement specific preventive strategies to reduce in-hospital-acquired infections after TAVI. Copyright © 2016 Elsevier Inc. All rights reserved.

The diagnosis and treatment of donovanosis (granuloma inguinale).

PubMed Central

Richens, J

1991-01-01

Donovanosis is a predominantly tropical cause of genital ulcer occurring chiefly in small endemic foci in all continents except Europe. Diagnosis requires the careful collection, staining and examination of smears or biopsies of characteristic genital and, occasionally, extragenital lesions for demonstration of the pathognomonic Donovan bodies (Calymmatobacterium granulomatis) within histiocytes. Successful isolation of C. granulomatis has rarely proved feasible, the last report being in 1962. Donovanosis has a characteristic histopathological picture which occasionally simulates epithelioma. The antibiotics reported as showing good activity in donovanosis are those with good activity against gram negative bacilli and whose lipid solubility ensures good intracellular penetration. They include streptomycin, chloramphenicol, erythromycin, lincomycin, cotrimoxazole and the tetracyclines. More recently, good results have been reported with norfloxacin and thiamphenicol. The treatment of donovanosis in pregnant women and patients with AIDS poses special problems. Complications of donovanosis such as elephantiasis, stricture and pelvic abscess may require surgery. Contacts should be traced for examination but only treated if lesions are found. Images PMID:1774048

Antimicrobial Resistance in Asia: Current Epidemiology and Clinical Implications

PubMed Central

Kang, Cheol-In

2013-01-01

Antimicrobial resistance has become one of the most serious public health concerns worldwide. Although circumstances may vary by region or country, it is clear that some Asian countries are epicenters of resistance, having seen rapid increases in the prevalence of antimicrobial resistance of major bacterial pathogens. In these locations, however, the public health infrastructure to combat this problem is very poor. The prevalence rates of methicillin-resistant Staphylococcus aureus (MRSA), macrolide-resistant Streptococcus pneumoniae, and multidrug-resistant enteric pathogens are very high due to the recent emergence of extremely drug-resistant gram-negative bacilli in Asia. Because antimicrobial options for these pathogens are extremely limited, infections caused by antimicrobial-resistant bacteria are often associated with inappropriate antimicrobial therapy and poor clinical outcomes. Physicians should be aware of the current epidemiological status of resistance and understand the appropriate use of antimicrobial agents in clinical practice. This review focuses on describing the epidemiology and clinical implications of antimicrobial-resistant bacterial infections in Asian countries. PMID:24265947

Redundancy and modularity in membrane-associated dissimilatory nitrate reduction in Bacillus

PubMed Central

Heylen, Kim; Keltjens, Jan

2012-01-01

The genomes of two phenotypically denitrifying type strains of the genus Bacillus were sequenced and the pathways for dissimilatory nitrate reduction were reconstructed. Results suggest that denitrification proceeds in the periplasmic space and in an analogous fashion as in Gram-negative organisms, yet with the participation of proteins that tend to be membrane-bound or membrane-associated. A considerable degree of functional redundancy was observed with marked differences between B. azotoformans LMG 9581T and B. bataviensis LMG 21833T. In addition to the already characterized menaquinol/cyt c-dependent nitric oxide reductase (Suharti et al., 2001, 2004) of which the encoding genes could be identified now, evidence for another novel nitric oxide reductase (NOR) was found. Also, our analyses confirm earlier findings on branched electron transfer with both menaquinol and cytochrome c as reductants. Quite unexpectedly, both bacilli have the disposal of two parallel pathways for nitrite reduction enabling a life style as a denitrifier and as an ammonifying bacterium. PMID:23087684

In Vitro Studies of Semisynthetic α- (Substituted-Ureido) Penicillins

PubMed Central

Bodey, Gerald P.; Stewart, Dorothy

1971-01-01

The activity of three α-(substituted-ureido) penicillins was evaluated in vitro against 599 clinical isolates of gram-negative bacilli, by use of the broth-dilution technique. At a concentration of 12.5 μg or less/ml, BL-P1597 inhibited 90% of isolates of Pseudomonas sp., 56% of Enterobacter sp., 67% of indole-positive Proteus spp., 72% of Escherichia coli, and 85% of Proteus mirabilis. BL-P1654 had similar activity, whereas BL-P1532 was much less active. At a concentration of 25 μg or less/ml, BL-P1597 also inhibited nearly 60% of isolates of Klebsiella sp. and nearly 40% of Serratia sp. BL-P1597 and BL-P1654 were as active as ampicillin and carbenicillin against E. coli and P. mirabilis. They were less active than carbenicillin against indole-positive Proteus spp. Both drugs were substantially more active than carbenicillin against Pseudomonas sp. A strain of Pseudomonas sp. which developed resistance to carbenicillin also developed resistance to the α-(substituted-ureido) penicillins simultaneously. PMID:4930281

Severe Legionnaire's disease caused by Legionella longbeachae in a long-term renal transplant patient: the importance of safe living strategies after transplantation.

PubMed

Wright, A J; Humar, A; Gourishankar, S; Bernard, K; Kumar, D

2012-08-01

Legionella species are intracellular gram-negative bacilli that require specific culture media for growth. Transplant recipients with impaired cellular immunity are at particular risk for infection with this pathogen. Most human disease is caused by Legionella pneumophila; disease caused by non-L. pneumophila species is reported mainly in immunosuppressed patients with the exception of Legionella longbeachae. L. longbeachae is a common cause of Legionnaires' disease in Australia and New Zealand, and is associated with exposure to potting soil. We report the case of a patient, 26 years post kidney transplant, who presented with severe and rapidly progressive respiratory illness. L. longbeachae serogroup 1 was isolated from respiratory cultures. Further investigation revealed that she had significant soil exposure before the onset of illness. We highlight the importance of following safe living strategies to prevent exposure-related illness even in long-term transplant recipients. © 2012 John Wiley & Sons A/S.

[Estimation of activity of pharmakopeal disinfectants and antiseptics against Gram-negative and Gram-positive bacteria isolated from clinical specimens, drugs and environment].

PubMed

Grzybowska, Wanda; Młynarczyk, Grazyna; Młynarczyk, Andrzej; Bocian, Ewa; Luczak, Mirosław; Tyski, Stefan

2007-01-01

The MIC of nine different disinfectants and antiseptics were determined for the Gram-negative and Gram-positive bacteria. Strains originated from clinical specimens, drugs and environment. A sensitivity was determined against chlorhexidinum digluconate (Gram-negative: 0,625-80 mg/L, Gram-positive: 0,3-10 mg/L), benzalconium chloride (Gram-negative: 2,5-1280 mg/L, Gram-positive: 1,25-20 mg/L), salicilic acid (Gram-negative and Gram-positive: 400-1600 mg/L), benzoic acid (Gram-negative: 800-1600 mg/L, Gram-positive: 400-1 600 mg/L), boric acid (Gram-negative: 800-12 800 mg/L, Gram-positive: 1 600-6400 mg/L), chloramine B (Gram-negative: 1600-6400 mg/L, Gram-positive:800- 6400 mg/L), jodine (Gram-negative: 200-1600 mg/L, Gram-positive: 200-1600 mg/L), etacridine lactate (Gram-negative: 40 do > 20480 mg/L, Gram-positive: 40-1280 mg/L) and resorcine (Gram-negative: 1600-6400 mg/L, Gram-positive: 800-6400 mg/L). Diversified values of MIC for different strains were obtained, especially in the case of benzalconium chloride, etacridine lactate, chlorhexidinum digluconate, boric acid and iodine. Strains isolated from environment were usually more susceptible to examined compounds than clinical strains. The biggest diversification of sensitivity was observed among strains originated from drugs where besides sensitive appeared strains characterizing by very high MIC values of some substances, eg. boric acid.

The clinical efficacy of a clarithromycin-based regimen for Mycobacterium avium complex disease: A nationwide post-marketing study.

PubMed

Kadota, Jun-Ichi; Kurashima, Atsuyuki; Suzuki, Katsuhiro

2017-05-01

The revised 2007 American Thoracic Society/Infectious Diseases Society of America statement recommend clarithromycin-based combination therapy for treatment of Mycobacterium avium complex lung disease and stipulates approximately 1 year of continuous treatment after bacilli negative conversion. However, supporting data are insufficient. Our objective was to obtain data on the clinical outcome of clarithromycin-based daily regimens by conducting a nationwide retrospective post-marketing study of M. avium complex lung disease. In accordance with the Japanese guidelines, patients were enrolled in this survey according to their chest radiographic findings and microbiologic test results. They were treated with a multidrug regimen including clarithromycin, rifampicin, and ethambutol (clarithromycin-based regimen) until bacilli negative conversion, and the treatment was continued for approximately 1 year after the initial conversion. Data were collected before administration, at the time of bacilli negative conversion, at the end of treatment, and at 6 months after the end of treatment. Of the 466 subjects enrolled in the study, 271 patients who received clarithromycin at 800 mg/day underwent evaluation for M. avium complex disease. The final bacilli negative conversion rate in those patients was 94.7%. The bacteriological relapse rate was 5.0% (5/100 patients). Bacteriological relapse was noted in patients treated for less than 15 months after conversion. No life-threatening or serious adverse drug reactions were observed. This study demonstrated that a clarithromycin-based daily regimen can yield a high bacteriological conversion rate in M. avium complex disease. After conversion, treatment for less than 15 months might be insufficient to prevent bacteriological relapse. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

[Spectrum and drug sensitivity of pathogenic bacteria in children with nephrotic syndrome complicated by urinary tract infection: an analysis of 97 cases].

PubMed

Song, Shao-Na; Zhang, Bi-Li; Wang, Wen-Hong; Zhang, Xuan

2012-09-01

To investigate the spectrum and drug sensitivity of pathogenic bacteria in children with nephrotic syndrome (NS) complicated by urinary tract infection (UTI). A retrospective analysis was performed on the spectrum and drug sensitivity of pathogenic bacteria in 97 children with NS complicated by UTI, who hospitalized from January to December, 2011. The incidence of UTI in children with NS was 36.5%. It was significantly more common in children with recurrent NS than in those with primary NS (44.0% vs 31.9%; P<0.05). These cases mainly presented with asymptomatic bacteriuria. Enterococcus was the most common pathogenic bacteria (50.5%), including Enterococcus faecium (29.4%) and Enterococcus faecalis (21.1%), followed by Gram-negative bacteria, such as Escherichia coli (15.6%) and Klebsiella pneumoniae (14.7%). Enterococcus was highly sensitive to nitrofurantoin, vacomycin and linezolid, but was highly resistant to tetracycline and moxifloxacin. More multi-resistant strains were detected in Enterococcus faecium than in Enterococcus faecalis (72% vs 17%; P<0.05). Escherichia coli and Klebsiella pneumoniae were highly sensitive to amikacin, imipenem and piperacillin/tazobactam. Of the Gram-negative bacteria, 25% produced extended spectrum β-lactamases (ESBLs). ESBLs-producing bacteria had 100% sensitivity to imipenem, amikacin and piperacillin/tazobactam but were highly resistant to ampicillin, cefazolin and ceftriaxone. Children with recurrent NS are more susceptible to UTI than those with primary NS. Enterococcus is becoming major pathogenic bacteria for UTI in children with NS and has relatively high drug resistance, and most strains of Enterococcus faecium are multi-resistant.

In vitro antagonistic effect of Lactobacillus on organisms associated with bacterial vaginosis.

PubMed

Strus, Magdalena; Malinowska, Magdalena; Heczko, Piotr B

2002-01-01

To assess antagonistic properties of Lactobacillus strains isolated from the vaginas of healthy women as compared to the most common bacterial agents related to vaginosis. Antagonistic activity of different Lactobacillus strains isolated from the vaginas of healthy women not treated for infections with an antibiotic for the previous three months was screened using an agar slab method. The activity was tested against test organisms associated with bacterial vaginosis and/or urinary tract infections: Staphylococcus aureus, Enterococcus faecalis, Streptococcus agalactiae, Escherichia coli, Gardnerella vaginalis, Peptostreptococcus anaerobius and Prevotella bivia. Many of the 146 Lactobacillus strains tested exerted apparent antagonistic activities against gram-positive aerobic cocci and gram-negative rods, such as S aureus and E coli, and a marked number of Lactobacillus strains inhibited facultative bacteria, such as Gardnerella vaginalis and the anaerobes P anaerobius and P bivia. Only a few lactobacilli were able to inhibit growth of E faecalis and S agalactiae. Indicator bacteria growth inhibition probably relies upon several different complementary mechanisms. The specific indicator bacteria species determines which mechanism predominates. Lactobacillus strains taken from normal vaginal flora demonstrated antagonistic activity against a variety of bacteria related to vaginal and urinary tract infections. The specific occurrence rates of active Lactobacillus strains are different, and this difference is dependent on the indicator bacteria species.

Corynebacterium species isolated from patients with mastitis.

PubMed

Paviour, Sue; Musaad, Sahar; Roberts, Sally; Taylor, Graeme; Taylor, Susan; Shore, Keith; Lang, Selwyn; Holland, David

2002-12-01

Corynebacteria were isolated from breast tissue, pus, or deep wound swabs of 24 women; the most common species isolated was the newly described Corynebacterium kroppenstedtii, followed by Corynebacterium amycolatum and Corynebacterium tuberculostearicum. Gram-positive bacilli were seen in samples sent for culture or in histological specimens for 12 women, and 9 of the 12 women from whom adequate histological specimens were obtained had conditions that met the criteria for granulomatous lobular mastitis, a chronic inflammatory disease of unknown etiology.

Effectiveness and safety of nitrofurantoin in outpatient male veterans.

PubMed

Ingalsbe, Michelle L; Wojciechowski, Amy L; Smith, Kelly A; Mergenhagen, Kari A

2015-08-01

The aim of the study was to assess both the safety and the effectiveness of nitrofurantoin in male veterans treated for urinary tract infections (UTIs) with varying degrees of renal impairment in the outpatient setting. Nitrofurantoin is an important oral option for treating UTIs given increasing resistance to commonly used agents. Nitrofurantoin is currently contraindicated in patients with a creatinine clearance (CrCl) of < 60 ml/min, but the reason for this threshold has not been well documented. Data were collected through a retrospective chart review from January 2004 to July 2013 of men who had received nitrofurantoin. Bivariate analyses followed by multivariate analyses were performed between patients experiencing clinical cure and those who did not, to determine factors significantly impacting effectiveness. The Gram stain of the organism causing the UTI and CrCl were significant factors impacting effectiveness. For every 1 ml/min increase in CrCl, the odds of clinical cure increased by 1.3%. Patients with Gram-negative UTIs predictably had 80% cure rates with CrCl around 60 ml/min. Patients with Gram-positive UTIs required higher CrCl, nearing 100 ml/min, to establish an 80% cure rate. Adverse effects did not vary with CrCl. The odds of clinical cure varied with CrCl and with the type of organism causing the UTI, while adverse events did not differ based on renal function. A minimum CrCl of 60 ml/min is suggested for men to achieve an 80% cure rate for UTIs with the most common urinary pathogens.

Symptomatic Peripheral Mycotic Aneurysms Due to Infective Endocarditis

PubMed Central

González, Isabel; Sarriá, Cristina; López, Javier; Vilacosta, Isidre; San Román, Alberto; Olmos, Carmen; Sáez, Carmen; Revilla, Ana; Hernández, Miguel; Caniego, Jose Luis; Fernández, Cristina

2014-01-01

Abstract Peripheral mycotic aneurysms (PMAs) are a relatively rare but serious complication of infective endocarditis (IE). We conducted the current study to describe and compare the current epidemiologic, microbiologic, clinical, diagnostic, therapeutic, and prognostic characteristics of patients with symptomatic PMAs (SPMAs). A descriptive, comparative, retrospective observational study was performed in 3 tertiary hospitals, which are reference centers for cardiac surgery. From 922 definite IE episodes collected from 1996 to 2011, 18 patients (1.9%) had SPMAs. Because all SPMAs developed in left-sided IE, we performed a comparative study between 719 episodes of left-sided IE without SPMAs and 18 episodes with SPMAs. We found a higher frequency of intravenous drug abuse, native valve IE, intracranial bleeding, septic emboli, multiple embolisms, and IE diagnostic delay >30 days in patients with SPMAs than in patients without SPMAs. The causal microorganisms were gram-positive cocci (n =10), gram-negative bacilli (n = 2), gram-positive bacilli (n = 3), Bartonella henselae (n = 1), Candida albicans (n = 1), and negative culture (n = 1). The median IE diagnosis delay was 15 days (interquartile range [IQR], 13–33 d) in the case of high-virulence microorganisms versus 45 days (IQR, 30–240 d) in the case of low- to medium-virulence microorganisms. Twelve SPMAs were intracranial and 6 were extracranial. In 10 cases (8 intracranial and 2 extracranial), SPMAs were the initial presentation of IE; the remaining cases developed symptoms during or after finishing parenteral antibiotic treatment. The initial diagnosis of intracranial SPMAs was made by computed tomography (CT) or magnetic resonance imaging in 6 unruptured aneurysms and by angiography in 6 ruptured aneurysms. The initial test in extracranial SPMAs was Doppler ultrasonography in limbs, CT in liver, and coronary angiography in heart. Four (3 intracranial, 1 extracranial) of 7 (6 intracranial, 1 extracranial) patients treated only with antibiotics died. Surgical resection was performed in 7 (3 intracranial, 4 extracranial) and endovascular repair in 4 (3 intracranial, 1 extracranial) patients; all of them survived. In conclusion, we found that SPMAs were a rare complication of IE that developed only in left-sided IE, and especially in native valves. Intracranial hemorrhage, embolism, multiple embolisms, and diagnostic delay of IE were more common in patients with SPMAs. The microbiologic profile was diverse, but microorganisms of low-medium virulence were predominant, and had a greater delayed diagnosis of IE than those caused by microorganisms of high virulence. SPMAs were often the initial presentation of IE. The most common location of SPMAs was intracranial. Noninvasive radiologic imaging techniques were the initial imaging test in intracranial unruptured SPMAs and in most extracranial SPMAs. Surgical and endovascular treatments were safe and effective. Endovascular treatment could be the first line of treatment in selected cases. Mortality was high in those cases treated only with antibiotics. PMID:24378742

Species identification and susceptibility to 17 antibiotics of coagulase-negative staphylococci isolated from clinical specimens.

PubMed

Marsik, F J; Brake, S

1982-04-01

A total of 299 isolates of gram-positive, catalase-positive, coagulase-negative cocci were isolated from a variety of specimens collected from patients at a large university hospital, and 281 (94%) were identified as staphylococci by established methods. Using the scheme of Kloos and Schleifer, we determined the species of the coagulase-negative staphylococci. Staphylococcus epidermidis was the cause of all bacteremias and the most commonly isolated species from bone, joint, and wound infections. Staphylococcus haemolyticus was the second most common isolate from wound infections, and Staphylococcus saprophyticus was the most commonly isolated species from urinary tract infections. Antibiograms to 17 antimicrobial agents were performed by a microdilution technique, and the results revealed that S. epidermidis was resistant to a water spectrum of antimicrobial agents than the other species of staphylococci were.

Species identification and susceptibility to 17 antibiotics of coagulase-negative staphylococci isolated from clinical specimens.

PubMed Central

Marsik, F J; Brake, S

1982-01-01

A total of 299 isolates of gram-positive, catalase-positive, coagulase-negative cocci were isolated from a variety of specimens collected from patients at a large university hospital, and 281 (94%) were identified as staphylococci by established methods. Using the scheme of Kloos and Schleifer, we determined the species of the coagulase-negative staphylococci. Staphylococcus epidermidis was the cause of all bacteremias and the most commonly isolated species from bone, joint, and wound infections. Staphylococcus haemolyticus was the second most common isolate from wound infections, and Staphylococcus saprophyticus was the most commonly isolated species from urinary tract infections. Antibiograms to 17 antimicrobial agents were performed by a microdilution technique, and the results revealed that S. epidermidis was resistant to a water spectrum of antimicrobial agents than the other species of staphylococci were. PMID:7068839

Molecular analysis of bacterial communities in raw cow milk and the impact of refrigeration on its structure and dynamics.

PubMed

Raats, Dina; Offek, Maya; Minz, Dror; Halpern, Malka

2011-05-01

The impact of refrigeration on raw cow milk bacterial communities in three farm bulk tanks and three dairy plant silo tanks was studied using two methods: DGGE and cloning. Both methods demonstrated that bacterial taxonomic diversity decreased during refrigeration. Gammaproteobacteria, especially Pseudomonadales, dominated the milk after refrigeration. Farm samples and dairy plant samples differed in their microbial community composition, the former showing prevalence of Gram-positive bacteria affiliated with the classes Bacilli, Clostridia and Actinobacteria, the latter showing prevalence of Gram-negative species belonging to the Gammaproteobacteria class. Actinobacteria prevalence in the farm milk samples immediately after collection stood at about 25% of the clones. A previous study had found that psychrotolerant Actinobacteria identified in raw cow milk demonstrated both lipolytic and proteolytic enzymatic activity. Thus, we conclude that although Pseudomonadales play an important role in milk spoilage after long periods of cold incubation, Actinobacteria occurrence may play an important role when assessing the quality of milk arriving at the dairy plant from different farms. As new cooling technologies reduce the initial bacterial counts of milk to very low levels, more sensitive and efficient methods to evaluate the bacterial quality of raw milk are required. The present findings are an important step towards achieving this goal. Copyright © 2010 Elsevier Ltd. All rights reserved.

Gram-negative, but not Gram-positive, bacteria elicit strong PGE2 production in human monocytes.

PubMed

Hessle, Christina C; Andersson, Bengt; Wold, Agnes E

2003-12-01

Gram-positive and Gram-negative bacteria induce different cytokine patterns in human mononuclear cells. We have seen that Gram-positives preferentially induce IL-12 and TNF-alpha, whereas Gram-negatives induce more IL-10, IL-6, and IL-8. In this study, we compared the capacity of these two groups of bacteria to induce PGE2. Monocytes stimulated with Gram-negative bacterial species induced much more PGE2 than did Gram-positive bacteria (5600 +/- 330 vs. 1700 +/- 670 pg/mL, p < 0.001). Blocking of COX-2 by NS398 abolished PGE2 production, but did not alter the cytokine patterns induced by Gram-positive and Gram-negative bacteria. We suggest that Gram-positive and Gram-negative bacteria may stimulate different innate effector functions; Gram-positive bacteria promoting cell-mediated effector functions whereas Gram-negative bacteria inducing mediators inhibiting the same.

Development and validation of a nomogram predicting recurrence risk in women with symptomatic urinary tract infection.

PubMed

Cai, Tommaso; Mazzoli, Sandra; Migno, Serena; Malossini, Gianni; Lanzafame, Paolo; Mereu, Liliana; Tateo, Saverio; Wagenlehner, Florian M E; Pickard, Robert S; Bartoletti, Riccardo

2014-09-01

To develop and externally validate a novel nomogram predicting recurrence risk probability at 12 months in women after an episode of urinary tract infection. The study included 768 women from Santa Maria Annunziata Hospital, Florence, Italy, affected by urinary tract infections from January 2005 to December 2009. Another 373 women with the same criteria enrolled at Santa Chiara Hospital, Trento, Italy, from January 2010 to June 2012 were used to externally validate and calibrate the nomogram. Univariate and multivariate Cox regression models tested the relationship between urinary tract infection recurrence risk, and patient clinical and laboratory characteristics. The nomogram was evaluated by calculating concordance probabilities, as well as testing calibration of predicted urinary tract infection recurrence with observed urinary tract infections. Nomogram variables included: number of partners, bowel function, type of pathogens isolated (Gram-positive/negative), hormonal status, number of previous urinary tract infection recurrences and previous treatment of asymptomatic bacteriuria. Of the original development data, 261 out of 768 women presented at least one episode of recurrence of urinary tract infection (33.9%). The nomogram had a concordance index of 0.85. The nomogram predictions were well calibrated. This model showed high discrimination accuracy and favorable calibration characteristics. In the validation group (373 women), the overall c-index was 0.83 (P = 0.003, 95% confidence interval 0.51-0.99), whereas the area under the receiver operating characteristic curve was 0.85 (95% confidence interval 0.79-0.91). The present nomogram accurately predicts the recurrence risk of urinary tract infection at 12 months, and can assist in identifying women at high risk of symptomatic recurrence that can be suitable candidates for a prophylactic strategy. © 2014 The Japanese Urological Association.

Nosocomial infections and risk factors in the intensive care unit of a teaching and research hospital: A prospecive cohort study

PubMed Central

Ak, Oznur; Batirel, Ayse; Ozer, Serdar; Čolakoğlu, Serhan

2011-01-01

Summary Background To evaluate the incidence, risk factors and etiology of nosocomial infections (NIs) in the intensive care unit (ICU) of our hospital in order to improve our infection control policies. Material/Methods A 1-year prospective cohort study of nosocomial infection (NI) surveillance was conducted in our ICU in 2008. Results Out of 1134 patients hospitalized in the ICU for a period of 6257 days, 115 patients acquired a total of 135 NIs distributed as follows: 36.3% bacteremia, 30.4% ventilator-associated pneumonia (VAP), 18.5% catheter-associated urinary tract infection, 7.4% central-line infection, 5.9% cutaneous infection, and 1.3% meningitis. The incidence rate of NI was 21.6 in 1000 patient-days, and the rate of NI was 25.6%. Length of ICU stay, central venous catheterisation, mechanical ventilation and tracheostomy were statistically significant risk factors for NI. Of all NI, 112 (83%) were microbiologically-confirmed and 68.8% of the isolates were Gram-negative, 27.6% were Gram-positive, and 3.6% were fungi. 23 (17%) were clinically-defined infections. The most frequently isolated organism was P. aeruginosa (25%), followed by S. aureus (21.4%), E. coli (18.7%) and A. baumannii (16.9%). Conclusions The bloodstream was the most common site and Gram-negatives were the most commonly reported causes of ICU infections. PMID:21525819

Characterization of fungal antagonistic bacilli isolated from aerial roots of banyan (Ficus benghalensis) using intact-cell MALDI-TOF mass spectrometry (ICMS).

PubMed

Pathak, K V; Keharia, H

2013-05-01

To characterize fungal antagonistic bacilli isolated from aerial roots of banyan tree and identify the metabolites responsible for their antifungal activity. Seven gram positive, endospore-forming, rod-shaped endophytic bacterial strains exhibiting a broad-spectrum antifungal activity were isolated from the surface-sterilized aerial roots of banyan tree. The isolates designated as K1, A2, A4 and A12 were identified as Bacillus subtilis, whereas isolates A11 and A13 were identified as Bacillus amyloliquefaciens using Biolog Microbial Identification System. The antifungal lipopeptides, surfactins, iturins and fengycins with masses varying in the range from m/z 900 to m/z 1550 could be detected using intact-cell MALDI-TOF mass spectrometry (ICMS). On the basis of mass spectral and carbon source utilization profile, all seven endophytes could be distinguished from each other. Furthermore, ICMS analysis revealed higher extent of heterogeneity among iturins and fengycins produced by B. subtilis K1, correlating well with its higher antifungal activity in comparison with other isolates. Seven fungal antagonistic bacilli were isolated from aerial roots of banyan tree, exhibiting broad spectrum of antifungal activity, among which B. subtilis K1 isolate was found to be most potent. The ICMS analysis revealed that all these isolates produced cyclic lipopeptides belonging to surfactin, iturin and fengycin families and exhibited varying degree of heterogeneity. The endophytes are considered as a potential source of novel bioactive metabolites, and this study describes the potent fungal antagonistic bacilli from aerial roots of banyan tree. The isolates described in this study have a prospective application as biocontrol agents. Also ICMS analysis described in this study for characterization of antifungal metabolites produced by banyan endophytic bacilli may be used as a high throughput tool for screening of microbes producing novel cyclic lipopeptides. © 2013 The Society for Applied Microbiology.

Genomic determinants of sporulation in Bacilli and Clostridia: towards the minimal set of sporulation-specific genes.

PubMed

Galperin, Michael Y; Mekhedov, Sergei L; Puigbo, Pere; Smirnov, Sergey; Wolf, Yuri I; Rigden, Daniel J

2012-11-01

Three classes of low-G+C Gram-positive bacteria (Firmicutes), Bacilli, Clostridia and Negativicutes, include numerous members that are capable of producing heat-resistant endospores. Spore-forming firmicutes include many environmentally important organisms, such as insect pathogens and cellulose-degrading industrial strains, as well as human pathogens responsible for such diseases as anthrax, botulism, gas gangrene and tetanus. In the best-studied model organism Bacillus subtilis, sporulation involves over 500 genes, many of which are conserved among other bacilli and clostridia. This work aimed to define the genomic requirements for sporulation through an analysis of the presence of sporulation genes in various firmicutes, including those with smaller genomes than B. subtilis. Cultivable spore-formers were found to have genomes larger than 2300 kb and encompass over 2150 protein-coding genes of which 60 are orthologues of genes that are apparently essential for sporulation in B. subtilis. Clostridial spore-formers lack, among others, spoIIB, sda, spoVID and safA genes and have non-orthologous displacements of spoIIQ and spoIVFA, suggesting substantial differences between bacilli and clostridia in the engulfment and spore coat formation steps. Many B. subtilis sporulation genes, particularly those encoding small acid-soluble spore proteins and spore coat proteins, were found only in the family Bacillaceae, or even in a subset of Bacillus spp. Phylogenetic profiles of sporulation genes, compiled in this work, confirm the presence of a common sporulation gene core, but also illuminate the diversity of the sporulation processes within various lineages. These profiles should help further experimental studies of uncharacterized widespread sporulation genes, which would ultimately allow delineation of the minimal set(s) of sporulation-specific genes in Bacilli and Clostridia. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Pharmacokinetics of Understudied Drugs Administered to Children Per Standard of Care

ClinicalTrials.gov

2018-04-02

Adenovirus; Anesthesia; Anxiety; Anxiolysis; Autism; Autistic Disorder; Bacterial Meningitis; Bacterial Septicemia; Benzodiazepine; Bipolar Disorder; Bone and Joint Infections; Central Nervous System Infections; Convulsions; Cytomegalovirus Retinitis; Early-onset Schizophrenia Spectrum Disorders; Epilepsy; General Anesthesia; Gynecologic Infections; Herpes Simplex Virus; Infantile Hemangioma; Infection; Inflammation; Inflammatory Conditions; Intra-abdominal Infections; Lower Respiratory Tract Infections; Migraines; Pain; Pneumonia; Schizophrenia; Sedation; Seizures; Skeletal Muscle Spasms; Skin and Skin-structure Infections; Thromboprophylaxis; Thrombosis; Treatment-resistant Schizophrenia; Urinary Tract Infections; Withdrawal; Sepsis; Gram-negative Infection; Bradycardia; Cardiac Arrest; Cardiac Arrhythmia; Staphylococcal Infections; Nosocomial Pneumonia; Neuromuscular Blockade; Methicillin Resistant Staphylococcus Aureus; Endocarditis; Neutropenia; Headache

Identification of key genes in Gram-positive and Gram-negative sepsis using stochastic perturbation

PubMed Central

Li, Zhenliang; Zhang, Ying; Liu, Yaling; Liu, Yanchun; Li, Youyi

2017-01-01

Sepsis is an inflammatory response to pathogens (such as Gram-positive and Gram-negative bacteria), which has high morbidity and mortality in critically ill patients. The present study aimed to identify the key genes in Gram-positive and Gram-negative sepsis. GSE6535 was downloaded from Gene Expression Omnibus, containing 17 control samples, 18 Gram-positive samples and 25 Gram-negative samples. Subsequently, the limma package in R was used to screen the differentially expressed genes (DEGs). Hierarchical clustering was conducted for the specific DEGs in Gram-negative and Gram-negative samples using cluster software and the TreeView software. To analyze the correlation of samples at the gene level, a similarity network was constructed using Cytoscape software. Functional and pathway enrichment analyses were conducted for the DEGs using DAVID. Finally, stochastic perturbation was used to determine the significantly differential functions between Gram-positive and Gram-negative samples. A total of 340 and 485 DEGs were obtained in Gram-positive and Gram-negative samples, respectively. Hierarchical clustering revealed that there were significant differences between control and sepsis samples. In Gram-positive and Gram-negative samples, myeloid cell leukemia sequence 1 was associated with apoptosis and programmed cell death. Additionally, NADH:ubiquinone oxidoreductase subunit S4 was associated with mitochondrial respiratory chain complex I assembly. Stochastic perturbation analysis revealed that NADH:ubiquinone oxidoreductase subunit B2 (NDUFB2), NDUFB8 and ubiquinol-cytochrome c reductase hinge protein (UQCRH) were associated with cellular respiration in Gram-negative samples, whereas large tumor suppressor kinase 2 (LATS2) was associated with G1/S transition of the mitotic cell cycle in Gram-positive samples. NDUFB2, NDUFB8 and UQCRH may be biomarkers for Gram-negative sepsis, whereas LATS2 may be a biomarker for Gram-positive sepsis. These findings may promote the therapies of sepsis caused by Gram-positive and Gram-negative bacteria. PMID:28714002

A Case Series and Review of Bacillus Cereus Endocarditis from India.

PubMed

Gopinathan, Anusha; Kumar, Anil; Sen, Amitabh C; Sudha, Srisruthy; Varma, Praveen; Gs, Sunil; Eapen, Malini; Dinesh, Kavitha R

2018-01-01

Bacillus cereus is a gram positive bacilli found commonly in the soil and environment. It is a bacteria rarely associated with endocarditis. Intravenous drug abuse, presence of valvular defects, pacemakers, immunodeficiency are some of the known risk factors for B.cereus endocarditis. We present here a case series of two patients with B.cereus endocarditis along with a review of the literature. This is the first report of B.cereus endocarditis from India to the best of our knowledge.

Clostridium perfringens type A fatal acute hemorrhagic gastroenteritis in a dog.

PubMed

Schlegel, Ben J; Van Dreumel, Tony; Slavić, Durda; Prescott, John F

2012-05-01

The morning after participating in a dog show, a 2-year-old Pomeranian dog was found dead in a pool of bloody feces. Necropsy revealed hemorrhagic gastroenteritis of the entire gastrointestinal tract, with many Gram-positive bacilli on the surface and in the lumen and crypts of the intestine. Enterotoxin-positive type A Clostridium perfringens were isolated in large numbers. This dramatic case of fatal C. perfringens gastroenteritis highlights the need to better understand the role of this bacterium in enteric disease of dogs.

Selective decontamination of the digestive tract ameliorates severe burn-induced insulin resistance in rats.

PubMed

Li, Jun; Zhu, Liang; Xu, Ming; Han, Juntao; Bai, Xiaozhi; Yang, Xuekang; Zhu, Huayu; Xu, Jie; Zhang, Xing; Gong, Yangfan; Hu, Dahai; Gao, Feng

2015-08-01

Severe burns often initiate the prevalence of hyperglycemia and insulin resistance, significantly contributing to adverse clinical outcomes. However, there are limited treatment options. This study was designed to investigate the role and the underlying mechanisms of oral antibiotics to selectively decontaminate the digestive tract (SDD) on burn-induced insulin resistance. Rats were subjected to 40% of total body surface area full-thickness burn or sham operation with or without SDD treatment. Translocation of FITC-labeled LPS was measured at 4h after burn. Furthermore, the effect of SDD on post-burn quantity of gram-negative bacteria in gut was investigated. Serum or muscle LPS and proinflammatory cytokines were measured. Intraperitoneal glucose tolerance test and insulin tolerance test were used to determine the status of systemic insulin resistance. Furthermore, intracellular insulin signaling (IRS-1 and Akt) and proinflammatory related kinases (JNK and IKKβ) were assessed by western blot. Burn increased the translocation of LPS from gut 4h after injury. SDD treatment effectively inhibited post-burn overgrowth of gram-negative enteric bacilli in gut. In addition, severe burns caused significant increases in the LPS and proinflammatory cytokines levels, activation of proinflammatory related kinases, and systemic insulin resistance as well. But SDD treatment could significantly attenuate burn-induced insulin resistance and improve the whole-body responsiveness to insulin, which was associated with the inhibition of gut-derived LPS, cytokines, proinflammatory related kinases JNK and IKKβ, as well as activation of IRS-1 and Akt. SDD appeared to have an effect on proinflammatory signaling cascades and further reduced severe burn-induced insulin resistance. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Tepidibacillus decaturensis sp. nov., a microaerophilic, moderately thermophilic iron-reducing bacterium isolated from 1.7 km depth groundwater

DOE PAGES

Dong, Yiran; Sanford, Robert A.; Boyanov, Maxim I.; ...

2016-10-01

Here, a Gram-stain-negative, microaerophilic rod-shaped organism designated as strain Z9 T was isolated from groundwater of 1.7 km depth from the Mt. Simon Sandstone of the Illinois Basin, Illinois, USA. Cells of strain Z9 T were rod shaped with dimensions of 0.3×(1–10) µm and stained Gram-negative. Strain Z9 T grew within the temperature range 20–60 °C (optimum at 30–40 °C), between pH 5 and 8 (optimum 5.2–5.8) and under salt concentrations of 1–5 % (w/v) NaCl (optimum 2.5 % NaCl). In addition to growth by fermentation and nitrate reduction, this strain was able to reduce Fe(III), Mn(IV), Co(III) and Cr(VI)more » when H 2 or organic carbon was available as the electron donor, but did not actively reduce oxidized sulfur compounds (e.g. sulfate, thiosulfate or S 0). The G+C content of the DNA from strain Z9 T was 36.1 mol%. Phylogenetic analysis of the 16S rRNA gene from strain Z9 T showed that it belongs to the class Bacilli and shares 97 % sequence similarity with the only currently characterized member of the genus Tepidibacillus, T. fermentans. Based on the physiological distinctness and phylogenetic information, strain Z9 T represents a novel species within the genus Tepidibacillus, for which the name Tepidibacillus decaturensis sp. nov. is proposed. The type strain is Z9 T (=ATCC BAA-2644 T=DSM 103037 T).« less

Tepidibacillus decaturensis sp. nov., a microaerophilic, moderately thermophilic iron-reducing bacterium isolated from 1.7 km depth groundwater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Yiran; Sanford, Robert A.; Boyanov, Maxim I.

Here, a Gram-stain-negative, microaerophilic rod-shaped organism designated as strain Z9 T was isolated from groundwater of 1.7 km depth from the Mt. Simon Sandstone of the Illinois Basin, Illinois, USA. Cells of strain Z9 T were rod shaped with dimensions of 0.3×(1–10) µm and stained Gram-negative. Strain Z9 T grew within the temperature range 20–60 °C (optimum at 30–40 °C), between pH 5 and 8 (optimum 5.2–5.8) and under salt concentrations of 1–5 % (w/v) NaCl (optimum 2.5 % NaCl). In addition to growth by fermentation and nitrate reduction, this strain was able to reduce Fe(III), Mn(IV), Co(III) and Cr(VI)more » when H 2 or organic carbon was available as the electron donor, but did not actively reduce oxidized sulfur compounds (e.g. sulfate, thiosulfate or S 0). The G+C content of the DNA from strain Z9 T was 36.1 mol%. Phylogenetic analysis of the 16S rRNA gene from strain Z9 T showed that it belongs to the class Bacilli and shares 97 % sequence similarity with the only currently characterized member of the genus Tepidibacillus, T. fermentans. Based on the physiological distinctness and phylogenetic information, strain Z9 T represents a novel species within the genus Tepidibacillus, for which the name Tepidibacillus decaturensis sp. nov. is proposed. The type strain is Z9 T (=ATCC BAA-2644 T=DSM 103037 T).« less

Development of the Nasopharyngeal Microbiota in Infants with Cystic Fibrosis.

PubMed

Prevaes, Sabine M P J; de Winter-de Groot, Karin M; Janssens, Hettie M; de Steenhuijsen Piters, Wouter A A; Tramper-Stranders, Gerdien A; Wyllie, Anne L; Hasrat, Raiza; Tiddens, Harm A; van Westreenen, Mireille; van der Ent, Cornelis K; Sanders, Elisabeth A M; Bogaert, Debby

2016-03-01

Cystic fibrosis (CF) is characterized by early structural lung disease caused by pulmonary infections. The nasopharynx of infants is a major ecological reservoir of potential respiratory pathogens. To investigate the development of nasopharyngeal microbiota profiles in infants with CF compared with those of healthy control subjects during the first 6 months of life. We conducted a prospective cohort study, from the time of diagnosis onward, in which we collected questionnaires and 324 nasopharynx samples from 20 infants with CF and 45 age-matched healthy control subjects. Microbiota profiles were characterized by 16S ribosomal RNA-based sequencing. We observed significant differences in microbial community composition (P < 0.0002 by permutational multivariate analysis of variance) and development between groups. In infants with CF, early Staphylococcus aureus and, to a lesser extent, Corynebacterium spp. and Moraxella spp. dominance were followed by a switch to Streptococcus mitis predominance after 3 months of age. In control subjects, Moraxella spp. enrichment occurred throughout the first 6 months of life. In a multivariate analysis, S. aureus, S. mitis, Corynebacterium accolens, and bacilli were significantly more abundant in infants with CF, whereas Moraxella spp., Corynebacterium pseudodiphtericum and Corynebacterium propinquum and Haemophilus influenzae were significantly more abundant in control subjects, after correction for age, antibiotic use, and respiratory symptoms. Antibiotic use was independently associated with increased colonization of gram-negative bacteria such as Burkholderia spp. and members of the Enterobacteriaceae bacteria family and reduced colonization of potential beneficial commensals. From diagnosis onward, we observed distinct patterns of nasopharyngeal microbiota development in infants with CF under 6 months of age compared with control subjects and a marked effect of antibiotic therapy leading toward a gram-negative microbial composition.

Presence, distribution and molecular epidemiology of multi-drug-resistant Gram-negative bacilli from medical personnel of intensive care units in Tianjin, China, 2007-2015.

PubMed

Liu, H; Fei, C N; Zhang, Y; Liu, G W; Liu, J; Dong, J

2017-06-01

Multi-drug-resistant Gram-negative bacteria (MDRGNB) have become an important cause of nosocomial infection in intensive care units (ICUs). To investigate the molecular epidemiology of MDRGNB isolated from medical personnel (MP) and non-medical personnel (NMP) at 69 ICUs in Tianjin, China. From April 2007 to October 2015, 2636 nasal and hand swab samples from 1185 MP and 133 NMP were cultured for GNB (including MDRGNB), meticillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The susceptibilities of GNB to 14 antimicrobial agents were determined, and 80 MDRGNB were characterized using pulsed-field gel electrophoresis (PFGE) and dendrogram analysis. In total, 301 GNB were identified in 269 MP, including 109 MDRGNB isolates in 104 MP. Forty-two GNB were isolated from 39 NMP, which included 20 NMP with MDRGNB. Overall, 8.8% of MP were colonized with MDRGNB, which greatly exceeded colonization rates with MRSA (0.9%) and VRE (0.1%). Three pairs of Klebsiella pneumoniae and one pair of Enterobacter aerogenes were indistinguishable from each other, but the majority of isolate tests had distinct PFGE profiles. The prevalence of MDRGNB was high among ICU MP in Tianjin, and greatly exceeded that of VRE and MRSA. There was no difference in the rates of nasal carriage of MDRGNB between MP and NMP, but NMP were significantly more likely to have hand colonization with MDRGNB. PFGE profiles showed that there was only limited sharing of strains of MDR E. aerogenes and K. pneumoniae between personnel. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

[Isolation of heterotrophic nitrifiers/aerobic denitrifiers and their roles in N2O production for different incubations].

PubMed

Jiang, Jing-Yan; Hu, Zheng-Hua; Huang, Yao

2009-07-15

Soil microorganisms are important sources of N2O for the atmosphere. Peak emissions of N2O are often observed after wetting of soil. The simultaneous heterotrophic nitrifying and aerobic denitrifying bacteria with respect to N2O emission were studied to obtain more information about the microbiologcal aspects of peak emissions. Using acetamide as the C and N source, two strains of nitrifying and denitrifying bacteria were isolated, coded as XM1 and HX2,respectively. XM1 strain was Gram-negative chain-like bacilli, and the HX2 was Gram-negative cocci. In enrichment culture, N2O production of HX2 was 76 times more than XM1. Two strains could grow with glucose, mannitol or sodium tartrate as sole carbon source, respectively. They could nitrify with sodium nitrate or denitrify with ammonium sulfate as unique nitrogen source, and produce intermediate product nitrite. XM1 strain growth velocity and nitrite formation were obviously higher than HX2. The phylogentic analysis based on partial 16S rDNA showed that two isolated strains were the closest relative of Pseudomonas sp.99% sequence similarity. Under different WFPS (water-filled-pore-space) conditions, the aerobic autoclaved soil incubation trial showed that, HX2 strain was suitable for growing in 30% WFPS, and N2O production was (36.01 +/- 2.48) ng/g which was 1.9 times than that in 60% WFPS. But XM1 was suitable for growing in 60% WFPS and almost had no N2O production. To investigate the nitrifying and denitrifying mechanisms of heterotrophic nitrifiers/aerobic denitrifiers should be useful for mastering the mitigation way of soil N2O emission in future.

Bacterial Viability within Dental Calculus: An Untrodden, Inquisitive Clinico-Patho- Microbiological Research.

PubMed

Gupta, Swati; Jain, P K; Kumra, Madhumani; Rehani, Shweta; Mathias, Yulia; Gupta, Ramakant; Mehendiratta, Monica; Chander, Anil

2016-07-01

Chronic inflammatory periodontal diseases i.e. gingivitis and periodontitis are one of the most common afflictions faced by human beings. Dental plaque, which is a pool of pathogenic microorganisms, remains to be current mainstay in etiopathogenesis. Dental calculus, which is a mineralized product of this plaque remains ignored and is considered merely as an ash heap of minor significance. However, the intriguing array in disease etiopathogenesis bulldozed researchers to suspect the role of calculus in disease chrysalis but still the viability of bacteria inside calculus and thus its pathogenicity remains an intricacy; the answer to which lies in the Pandora's Box. The present study was undertaken to investigate the viability of bacteria within dental calculus along with their identification. Also, to classify dental calculus on the basis of mineralization and to observe the variation of viable microflora found in dental calculus with the extent of mineralization and disease severity. A total of 60 samples were obtained, by harvesting two samples of supragingival calculus from each patient having chronic inflammatory periodontal disease. These samples were divided into two groups (Group A and Group B). Samples of Group A were kept non-irradiated and samples of Group B were exposed to UV radiation. The samples were categorized into less, moderately and highly mineralized according to the force required for crushing them. All the crushed calculus samples were then divided into three parts. These were used for dark-field microscopy, gram staining and bacterial cultures. Bacterial identification of the cultures obtained was also carried out by performing various biochemical assays. The present study revealed the presence of motile spirochaetes within the samples under dark-field microscope. Gram staining revealed presence of numerous gram positive cocci and gram negative bacilli. Bacterial cultures showed growth of variety of aerobic and capnophilic microorganisms. The present study concludes the presence of viable aerobic and capnophilic bacteria inside dental calculus which may reside within the lacunae and channels in the calculus.

Surgical Site Infections in Pediatric Spine Surgery: Comparative Microbiology of Patients with Idiopathic and Nonidiopathic Etiologies of Spine Deformity.

PubMed

Maesani, Matthieu; Doit, Catherine; Lorrot, Mathie; Vitoux, Christine; Hilly, Julie; Michelet, Daphné; Vidal, Christophe; Julien-Marsollier, Florence; Ilharreborde, Brice; Mazda, Keyvan; Bonacorsi, Stéphane; Dahmani, Souhayl

2016-01-01

Surgical site infections (SSIs) are a concern in pediatric spine surgery with unusually high rates for a clean surgery and especially for patients with deformity of nonidiopathic etiology. Microbiologic differences between etiologies of spine deformities have been poorly investigated. We reviewed all cases of SSI in spinal surgery between 2007 and 2011. Characteristics of cases and of bacteria according to the etiology of the spine disease were investigated. Of 496 surgeries, we identified 51 SSIs (10.3%) in 49 patients. Staphylococcus aureus was the most frequent pathogen whatever the etiology (n = 31, 61% of infection cases). The second most frequent pathogens vary according to the etiology of the spine deformity. It was Gram-negative bacilli (GNB) in nonidiopathic cases (n = 19, 45% of cases) and anaerobe in idiopathic cases (n = 8, 38% of cases), particularly Gram-positive anaerobic cocci (n = 5, 24% of cases). Infection rate was 6.8% in cases with idiopathic spine disease (n = 21) and 15.9% in cases with nonidiopathic spine disease (n = 30). Nonidiopathic cases were more frequently male with lower weight. American Society of Anesthesiologists score was more often greater than 2, they had more frequently sacral implants and postoperative intensive care unit stay. GNB were significantly associated with a nonidiopathic etiology, low weight, younger age and sacral fusion. SSIs were polymicrobial in 31% of cases with a mean of 1.4 species per infection cases. S. aureus is the first cause of SSI in pediatric spine surgery. However, Gram-positive anaerobic cocci should be taken into account in idiopathic patients and GNB in nonidiopathic patients when considering antibiotic prophylaxis and curative treatment.

Bacteremic complications of intravascular catheter tip colonization with Gram-negative micro-organisms in patients without preceding bacteremia.

PubMed

van Eck van der Sluijs, A; Oosterheert, J J; Ekkelenkamp, M B; Hoepelman, I M; Peters, Edgar J G

2012-06-01

Although Gram-negative micro-organisms are frequently associated with catheter-related bloodstream infections, the prognostic value and clinical implication of a positive catheter tip culture with Gram-negative micro-organisms without preceding bacteremia remains unclear. We determined the outcomes of patients with intravascular catheters colonized with these micro-organisms, without preceding positive blood cultures, and identified risk factors for the development of subsequent Gram-negative bacteremia. All patients with positive intravascular catheter tip cultures with Gram-negative micro-organisms at the University Medical Center, Utrecht, The Netherlands, between 2005 and 2009, were retrospectively studied. Patients with Gram-negative bacteremia within 48 h before catheter removal were excluded. The main outcome measure was bacteremia with Gram-negative micro-organisms. Other endpoints were length of the hospital stay, in-hospital mortality, secondary complications of Gram-negative bacteremia, and duration of intensive care admission. A total of 280 catheters from 248 patients were colonized with Gram-negative micro-organisms. Sixty-seven cases were excluded because of preceding positive blood cultures, leaving 213 catheter tips from 181 patients for analysis. In 40 (19%) cases, subsequent Gram-negative bacteremia developed. In multivariate analysis, arterial catheters were independently associated with subsequent Gram-negative bacteremia (odds ratio [OR] = 5.00, 95% confidence interval [CI]: 1.20-20.92), as was selective decontamination of the digestive tract (SDD) (OR = 2.47, 95% CI: 1.07-5.69). Gram-negative bacteremia in patients who received SDD was predominantly caused by cefotaxime (part of the SDD)-resistant organisms. Mortality was significantly higher in the group with subsequent Gram-negative bacteremia (35% versus 20%, OR = 2.12, 95% CI: 1.00-4.49). Patients with a catheter tip colonized with Gram-negative micro-organisms had a high chance of subsequent Gram-negative bacteremia from any cause. This may be clinically relevant, as starting antibiotic treatment pre-emptively in high-risk patients with Gram-negative micro-organisms cultured from arterial intravenous catheters may be beneficial.

Antibiotic resistance in children with recurrent or complicated urinary tract infection.

PubMed

Younis, N; Quol, K; Al-Momani, T; Al-Awaisheh, F; Al-Kayed, D

2009-01-01

Urinary tract infection is certainly one of the most common childhood infections. Emerging resistance to the antibiotics is not unusual. Current hospitalization for children with urinary tract infection is reserved for severe or complicated cases. The aim of the present study was to determine the antibiotic resistance pattern among children with recurrent or complicated urinary tract infection. A retrospective study carried out at Prince Hashem hospital, Zarqa city, eastern Jordan and involved 336 episodes of culture proved urinary tract infection obtained from 121 patients with recurrent UTI, who used prophylactic antibiotics during the period from April 1, 2004 to December 31, 2006. The isolated microorganisms and there antibiotics susceptibility were studied. Seventy three patients (60.3%) were found to have some forms of urinary tract anomaly, significantly more prevalent among male children P<0.001. Vesicoureteral reflux being the most common (58.9%). Renal scars were significantly more prevalent among those with complicated rather than recurrent urinary tract infection (64.3% vs. 16.6%, P<0.001). Gram negative organisms were the most frequent isolates in patients with recurrent and complicated urinary tract infection. Proteus, Pseudomonas and Candida spp. were more prevalent in patients with complicated (P<0.001), and isolates in patients with UTA were significantly more resistant to most antibiotics tested. Pediatric urine culture isolates are becoming increasingly resistant to commonly used antibiotics. Empirical treatment with Trimethoprim-Sulfamethoxazole (TMP-SMX) or Cephalexin as the initial drug is ineffective. Nitrofurantoin and Nalidixic acid can be considered as the first line antibiotics for prophylaxis and or treatment of patients with recurrent UTI, while Meropenam and Ciprofloxacin can be used empirically in treating patients with complicated UTI.

Effects of pathogen-specific clinical mastitis on probability of conception in Holstein dairy cows.

PubMed

Hertl, J A; Schukken, Y H; Welcome, F L; Tauer, L W; Gröhn, Y T

2014-11-01

The objective of this study was to estimate the effects of pathogen-specific clinical mastitis (CM), occurring in different weekly intervals before or after artificial insemination (AI), on the probability of conception in Holstein cows. Clinical mastitis occurring in weekly intervals from 6 wk before until 6 wk after AI was modeled. The first 4 AI in a cow's lactation were included. The following categories of pathogens were studied: Streptococcus spp. (comprising Streptococcus dysgalactiae, Streptococcus uberis, and other Streptococcus spp.); Staphylococcus aureus; coagulase-negative staphylococci (CNS); Escherichia coli; Klebsiella spp.; cases with CM signs but no bacterial growth (above the level that can be detected from our microbiological procedures) observed in the culture sample and cases with contamination (≥ 3 pathogens in the sample); and other pathogens [including Citrobacter, yeasts, Trueperella pyogenes, gram-negative bacilli (i.e., gram-negative organisms other than E. coli, Klebsiella spp., Enterobacter, and Citrobacter), Corynebacterium bovis, Corynebacterium spp., Pasteurella, Enterococcus, Pseudomonas, Mycoplasma, Prototheca, and others]. Other factors included in the model were parity (1, 2, 3, 4 and higher), season of AI (winter, spring, summer, autumn), day in lactation of first AI, farm, and other non-CM diseases (retained placenta, metritis, ketosis, displaced abomasum). Data from 90,271 AI in 39,361 lactations in 20,328 cows collected from 2003/2004 to 2011 from 5 New York State dairy farms were analyzed in a generalized linear mixed model with a Poisson distribution. The largest reductions in probability of conception were associated with CM occurring in the week before AI or in the 2 wk following AI. Escherichia coli and Klebsiella spp. had the greatest adverse effects on probability of conception. The probability of conception for a cow with any combination of characteristics may be calculated based on the parameter estimates. These findings may be helpful to farmers in assessing reproduction in their dairy cows for more effective cow management. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Urinary Excretion and Bactericidal Activities of Gemifloxacin and Ofloxacin after a Single Oral Dose in Healthy Volunteers

PubMed Central

Naber, Christoph K.; Hammer, Michaela; Kinzig-Schippers, Martina; Sauber, Christian; Sörgel, Fritz; Bygate, Elizabeth A.; Fairless, Amanda J.; Machka, Konstanze; Naber, Kurt G.

2001-01-01

In a randomized crossover study, 16 volunteers (8 men, 8 women) received single oral doses of 320 mg of gemifloxacin and 400 mg of ofloxacin on two separate occasions in the fasting state to assess the urinary excretion and urinary bactericidal titers (UBTs) at intervals for up to 144 h. Ofloxacin showed higher concentrations in urine compared with those of gemifloxacin. The median (range) cumulative excretion of gemifloxacin was 29.7% (8.4 to 48.7%) of the parent drug administered, and median (range) cumulative excretion of ofloxacin was 84.3% (46.5 to 95.2%) of the parent drug administered. The UBTs, i.e., the highest twofold dilutions (with antibiotic-free urine as the diluent) of urine that were still bactericidal, were determined for a reference strain and nine uropathogens for which the MICs of gemifloxacin and ofloxacin were as follows: Escherichia coli ATCC 25922, 0.016 and 0.06 μg/ml, respectively; Klebsiella pneumoniae, 0.03 and 0.06 μg/ml, respectively; Proteus mirabilis, 0.125 and 0.125 μg/ml, respectively; Escherichia coli, 0.06 and 0.5 μg/ml, respectively; Pseudomonas aeruginosa, 1 and 4 μg/ml, respectively; Staphylococcus aureus, 0.008 and 0.25 μg/ml, respectively; Enterococcus faecalis, 0.06 and 2 μg/ml, respectively; Staphylococcus aureus, 0.25 and 4 μg/ml, respectively; Enterococcus faecalis, 0.5 and 32 μg/ml, respectively; and Staphylococcus aureus, 2 and 32 μg/ml, respectively. Generally, the UBTs for gram-positive uropathogens were higher for gemifloxacin than for ofloxacin and the UBTs for gram-negative uropathogens were higher for ofloxacin than for gemifloxacin. According to the UBTs, ofloxacin-resistant uropathogens (MICs, ≥4 mg/liter) should also be considered gemifloxacin resistant. Although clinical trials have shown that gemifloxacin is effective for the treatment of uncomplicated urinary tract infections, whether an oral dosage of 320 mg of gemifloxacin once daily is also adequate for the treatment of complicated urinary tract infections has yet to be confirmed. PMID:11709334

Urinary excretion and bactericidal activities of gemifloxacin and ofloxacin after a single oral dose in healthy volunteers.

PubMed

Naber, C K; Hammer, M; Kinzig-Schippers, M; Sauber, C; Sörgel, F; Bygate, E A; Fairless, A J; Machka, K; Naber, K G

2001-12-01

In a randomized crossover study, 16 volunteers (8 men, 8 women) received single oral doses of 320 mg of gemifloxacin and 400 mg of ofloxacin on two separate occasions in the fasting state to assess the urinary excretion and urinary bactericidal titers (UBTs) at intervals for up to 144 h. Ofloxacin showed higher concentrations in urine compared with those of gemifloxacin. The median (range) cumulative excretion of gemifloxacin was 29.7% (8.4 to 48.7%) of the parent drug administered, and median (range) cumulative excretion of ofloxacin was 84.3% (46.5 to 95.2%) of the parent drug administered. The UBTs, i.e., the highest twofold dilutions (with antibiotic-free urine as the diluent) of urine that were still bactericidal, were determined for a reference strain and nine uropathogens for which the MICs of gemifloxacin and ofloxacin were as follows: Escherichia coli ATCC 25922, 0.016 and 0.06 microg/ml, respectively; Klebsiella pneumoniae, 0.03 and 0.06 microg/ml, respectively; Proteus mirabilis, 0.125 and 0.125 microg/ml, respectively; Escherichia coli, 0.06 and 0.5 microg/ml, respectively; Pseudomonas aeruginosa, 1 and 4 microg/ml, respectively; Staphylococcus aureus, 0.008 and 0.25 microg/ml, respectively; Enterococcus faecalis, 0.06 and 2 microg/ml, respectively; Staphylococcus aureus, 0.25 and 4 microg/ml, respectively; Enterococcus faecalis, 0.5 and 32 microg/ml, respectively; and Staphylococcus aureus, 2 and 32 microg/ml, respectively. Generally, the UBTs for gram-positive uropathogens were higher for gemifloxacin than for ofloxacin and the UBTs for gram-negative uropathogens were higher for ofloxacin than for gemifloxacin. According to the UBTs, ofloxacin-resistant uropathogens (MICs, >or=4 mg/liter) should also be considered gemifloxacin resistant. Although clinical trials have shown that gemifloxacin is effective for the treatment of uncomplicated urinary tract infections, whether an oral dosage of 320 mg of gemifloxacin once daily is also adequate for the treatment of complicated urinary tract infections has yet to be confirmed.

Risk factors and pathogenic significance of severe sepsis and septic shock in 2286 patients with gram-negative bacteremia.

PubMed

Kang, Cheol-In; Song, Jae-Hoon; Chung, Doo Ryeon; Peck, Kyong Ran; Ko, Kwan Soo; Yeom, Joon-Sup; Ki, Hyun Kyun; Son, Jun Seong; Lee, Seung Soon; Kim, Yeon-Sook; Jung, Sook-In; Kim, Shin-Woo; Chang, Hyun-Ha; Ryu, Seong Yeol; Kwon, Ki Tae; Lee, Hyuck; Moon, Chisook

2011-01-01

The aim of this study was to identify risk factors for development of severe sepsis or septic shock and to evaluate the clinical impact of severe sepsis on outcome in patients with gram-negative bacteremia (GNB). From the database of a nationwide surveillance for bacteremia, patients with GNB were analyzed. Data of patients with severe sepsis or septic shock were compared with those of patient with sepsis. Of 2286 patients with GNB, 506 (22.1%) fulfilled the criteria of severe sepsis or septic shock. Factors associated with severe sepsis or septic shock in the multivariate analysis included renal disease, indwelling urinary catheter, hematologic malignancy, and neutropenia. The 30-day mortality of patients with severe sepsis or septic shock was significantly higher than that of patients with sepsis (39.5% [172/435] vs. 7.4% [86/1170]; P < 0.001). Multivariable analysis revealed that solid tumor, liver disease, pulmonary disease, pneumonia, and pathogens other than Escherichia coli, which were risk factors of development of severe sepsis or septic shock, were also found to be strong predictors of mortality. Severe sepsis or septic shock was a significant factor associated with mortality (OR, 3.34; 95% CI, 2.35-4.74), after adjustment for other variables predicting poor prognosis. Severe sepsis or septic shock was a common finding in patients with GNB, predicting a higher mortality rate. Renal disease and indwelling urinary catheter were the most important risk factors significantly associated with severe sepsis or septic shock among patients with GNB. Copyright © 2010 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Performance of Two Resin-Containing Blood Culture Media in Detection of Bloodstream Infections and in Direct Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry (MALDI-TOF MS) Broth Assays for Isolate Identification: Clinical Comparison of the BacT/Alert Plus and Bactec Plus Systems

PubMed Central

Fiori, Barbara; D'Inzeo, Tiziana; Di Florio, Viviana; De Maio, Flavio; De Angelis, Giulia; Giaquinto, Alessia; Campana, Lara; Tanzarella, Eloisa; Tumbarello, Mario; Antonelli, Massimo; Spanu, Teresa

2014-01-01

We compared the clinical performances of the BacT/Alert Plus (bioMérieux) and Bactec Plus (Becton Dickinson) aerobic and anaerobic blood culture (BC) media with adsorbent polymeric beads. Patients ≥16 years old with suspected bloodstream infections (BSIs) were enrolled in intensive care units and infectious disease wards. A single 40-ml blood sample was collected from each and used to inoculate (10 ml/bottle) one set of BacT/Alert Plus cultures and one set of Bactec Plus cultures, each set consisting of one aerobic and one anaerobic bottle. Cultures were incubated ≤5 days in the BacT/Alert 3D and Bactec FX instruments, respectively. A total of 128 unique BSI episodes were identified based on the recovery of clinically significant growth in 212 aerobic cultures (106 BacT/Alert and 106 Bactec) and 151 anaerobic cultures (82 BacT/Alert and 69 Bactec). The BacT/Alert aerobic medium had higher recovery rates for Gram-positive cocci (P = 0.024), whereas the Bactec aerobic medium was superior for recovery of Gram-negative bacilli (P = 0.006). BacT/Alert anaerobic medium recovery rates exceeded those of the Bactec anaerobic medium for total organisms (P = 0.003), Gram-positive cocci (P = 0.013), and Escherichia coli (P = 0.030). In terms of capacity for diagnosing the 128 septic episodes, the BacT/Alert and Bactec sets were comparable, although the former sets diagnosed more BSIs caused by Gram-positive cocci (P = 0.008). They also allowed earlier identification of coagulase-negative staphylococcal growth (mean, 2.8 h; P = 0.003) and growth in samples from patients not on antimicrobial therapy that yielded positive results (mean, 1.3 h; P < 0.001). Similarly high percentages of microorganisms in BacT/Alert and Bactec cultures (93.8% and 93.3%, respectively) were identified by direct matrix-assisted laser desorption ionization–time of flight mass spectrometry assay of BC broths. The BacT/Alert Plus media line appears to be a reliable, timesaving tool for routine detection of BSIs in the population we studied, although further studies are needed to evaluate their performance in other settings. PMID:25031441

Surface-Layer (S-Layer) Proteins Sap and EA1 Govern the Binding of the S-Layer-Associated Protein BslO at the Cell Septa of Bacillus anthracis

PubMed Central

Kern, Valerie J.; Kern, Justin W.; Theriot, Julie A.; Schneewind, Olaf

2012-01-01

The Gram-positive pathogen Bacillus anthracis contains 24 genes whose products harbor the structurally conserved surface-layer (S-layer) homology (SLH) domain. Proteins endowed with the SLH domain associate with the secondary cell wall polysaccharide (SCWP) following secretion. Two such proteins, Sap and EA1, have the unique ability to self-assemble into a paracrystalline layer on the surface of bacilli and form S layers. Other SLH domain proteins can also be found within the S layer and have been designated Bacillus S-layer-associated protein (BSLs). While both S-layer proteins and BSLs bind the same SCWP, their deposition on the cell surface is not random. For example, BslO is targeted to septal peptidoglycan zones, where it catalyzes the separation of daughter cells. Here we show that an insertional lesion in the sap structural gene results in elongated chains of bacilli, as observed with a bslO mutant. The chain length of the sap mutant can be reduced by the addition of purified BslO in the culture medium. This complementation in trans can be explained by an increased deposition of BslO onto the surface of sap mutant bacilli that extends beyond chain septa. Using fluorescence microscopy, we observed that the Sap S layer does not overlap the EA1 S layer and slowly yields to the EA1 S layer in a growth-phase-dependent manner. Although present all over bacilli, Sap S-layer patches are not observed at septa. Thus, we propose that the dynamic Sap/EA1 S-layer coverage of the envelope restricts the deposition of BslO to the SCWP at septal rings. PMID:22609927

Persistent bacteremia secondary to delayed identification of Lactobacillus in the setting of mitral valve endocarditis.

PubMed

Stroupe, Cody; Pendley, Joseph; Isang, Emmanuel; Helms, Benjamin

2017-01-01

Lactobacillus species causing infective endocarditis is rare. Most reported cases arise from the oral ingestion of Lactobacillus via dairy or nutritional supplements in patients with congenital valve disease or replacement. We present a case of native valve bacterial endocarditis caused by Lactobacillus arising from dental abscesses. Additionally, there was an error in identification of the Lactobacillus as Corynebacterium , which led to inadequate treatment. A 51-year-old male presented to an outside clinic with several weeks of subjective fevers and malaise. The provider obtained two sets of blood cultures. Both grew Gram-positive bacilli identified as Corynebacterium . Once hospitalized he persistently had positive blood cultures despite treatment with vancomycin and gentamicin. The specimens were sent to a reference lab. The cultures were confirmed to be Lactobacillus zeae resistant to vancomycin and gentamicin. Once he was started on appropriate therapy his blood cultures showed no further growth of bacteria. The infected teeth were removed as it was felt they were the source of the bacteremia. This case presents two interesting topics in one encounter. First, Lactobacillus is not a common culprit in endocarditis. Secondly, the incorrect identification of the gram-positive bacilli bacteria led to prolonged bacteremia in our patient. The patient was evaluated by cardiothoracic surgery at our facility and it was determined that he would likely need a mitral valve replacement versus repair. The decision was made to treat the patient with six weeks Penicillin-VK prior to the operation. He is currently completing his antibiotic therapy.

Honey Bee as Alternative Medicine to Treat Eleven Multidrug-Resistant Bacteria Causing Urinary Tract Infection during Pregnancy.

PubMed

Bouacha, Mabrouka; Ayed, Hayette; Grara, Nedjoud

2018-04-13

Medicinal benefits of honey bee have been recognized in the medical community since ancient times as a remedy for many diseases and infections. This study aimed to investigate the in vitro susceptibility of 11 multidrug-resistant bacterial strains, isolated from urinary tract infections of pregnant women, to six honey samples collected from different localities in the east of Algeria. The evaluation of the antibacterial activity was performed by the well method followed by the broth dilution method using two-fold dilutions of each honey sample ranging from 2.5 to 80% (w/v). The results obtained in this study revealed that all tested honeys exhibited potent antibacterial activity against the tested strains. The diameters of inhibition ranged from 19.67 to 53.33 mm, with minimum inhibitory concentrations (MICs) ranging from 2.5 to 40% (w/v) and minimum bactericidal concentration (MBCs) varied between 2.5 and 80% (w/v). Gram-positive bacteria were found to be more susceptible than Gram-negative bacteria with diameters ranging from 43.33 to 53.33 mm; MIC and MBC values ranged from 2.5 to 5% (w/v). The P.aeruginosa strain was found to be less susceptible than other strains with inhibitory diameters ranging from 19.67 to 27.33 mm; MICs ranged from 20 to 40% and MBCs ranged from 20 to 80% ( w/v ). This contribution has provided a broad overview of the antibacterial activity of Algerian honey and shown that honey bee has great potential for therapeutic use as an alternative therapy for urinary tract infection treatment which is safe and efficient during pregnancy.

Automatic detection of mycobacterium tuberculosis using artificial intelligence

PubMed Central

Xiong, Yan; Ba, Xiaojun; Hou, Ao; Zhang, Kaiwen; Chen, Longsen

2018-01-01

Background Tuberculosis (TB) is a global issue that seriously endangers public health. Pathology is one of the most important means for diagnosing TB in clinical practice. To confirm TB as the diagnosis, finding specially stained TB bacilli under a microscope is critical. Because of the very small size and number of bacilli, it is a time-consuming and strenuous work even for experienced pathologists, and this strenuosity often leads to low detection rate and false diagnoses. We investigated the clinical efficacy of an artificial intelligence (AI)-assisted detection method for acid-fast stained TB bacillus. Methods We built a convolutional neural networks (CNN) model, named tuberculosis AI (TB-AI), specifically to recognize TB bacillus. The training set contains 45 samples, including 30 positive cases and 15 negative cases, where bacilli are labeled by human pathologists. Upon training the neural network model, 201 samples (108 positive cases and 93 negative cases) were collected as test set and used to examine TB-AI. We compared the diagnosis of TB-AI to the ground truth result provided by human pathologists, analyzed inconsistencies between AI and human, and adjusted the protocol accordingly. Trained TB-AI were run on the test data twice. Results Examined against the double confirmed diagnosis by pathologists both via microscopes and digital slides, TB-AI achieved 97.94% sensitivity and 83.65% specificity. Conclusions TB-AI can be a promising support system to detect stained TB bacilli and help make clinical decisions. It holds the potential to relieve the heavy workload of pathologists and decrease chances of missed diagnosis. Samples labeled as positive by TB-AI must be confirmed by pathologists, and those labeled as negative should be reviewed to make sure that the digital slides are qualified. PMID:29707349

Automatic detection of mycobacterium tuberculosis using artificial intelligence.

PubMed

Xiong, Yan; Ba, Xiaojun; Hou, Ao; Zhang, Kaiwen; Chen, Longsen; Li, Ting

2018-03-01

Tuberculosis (TB) is a global issue that seriously endangers public health. Pathology is one of the most important means for diagnosing TB in clinical practice. To confirm TB as the diagnosis, finding specially stained TB bacilli under a microscope is critical. Because of the very small size and number of bacilli, it is a time-consuming and strenuous work even for experienced pathologists, and this strenuosity often leads to low detection rate and false diagnoses. We investigated the clinical efficacy of an artificial intelligence (AI)-assisted detection method for acid-fast stained TB bacillus. We built a convolutional neural networks (CNN) model, named tuberculosis AI (TB-AI), specifically to recognize TB bacillus. The training set contains 45 samples, including 30 positive cases and 15 negative cases, where bacilli are labeled by human pathologists. Upon training the neural network model, 201 samples (108 positive cases and 93 negative cases) were collected as test set and used to examine TB-AI. We compared the diagnosis of TB-AI to the ground truth result provided by human pathologists, analyzed inconsistencies between AI and human, and adjusted the protocol accordingly. Trained TB-AI were run on the test data twice. Examined against the double confirmed diagnosis by pathologists both via microscopes and digital slides, TB-AI achieved 97.94% sensitivity and 83.65% specificity. TB-AI can be a promising support system to detect stained TB bacilli and help make clinical decisions. It holds the potential to relieve the heavy workload of pathologists and decrease chances of missed diagnosis. Samples labeled as positive by TB-AI must be confirmed by pathologists, and those labeled as negative should be reviewed to make sure that the digital slides are qualified.

Association of high mortality with extended-spectrum β-lactamase (ESBL) positive cultures in community acquired infections.

PubMed

Ray, Sumit; Anand, Dimple; Purwar, Sankalp; Samanta, Arijit; Upadhye, Kaustubh V; Gupta, Prasoon; Dhar, Debashis

2018-04-01

Infections due to multidrug resistant organisms have become a serious health concern worldwide. The present study was conducted to investigate the spectrum of microbial resistance pattern in the community and their effects on mortality. A retrospective review and analysis of prospectively collected data was done of all patients admitted with diagnosis of sepsis in two tertiary care ICU's for a period of two years. Demographics, culture positivity, microbial spectrum, resistance pattern and outcome data were collected. Out of 5309 patients enrolled; 3822 had suspected clinical infection on admission with 1452 patients growing positive microbial cultures. Among these, 201 bacterial strains were isolated from patients who had community acquired infections. 73% were Gram negative bacilli, commonest being E. coli (63%). 63.4% E. coli and 60.7% Klebsiella isolates were ESBL producers. The mortality in ESBL positive infections was significantly higher as compared to ESBL negative infections (Odds ratio 2.756). Moreover, ESBL positive patients empirically treated with Beta Lactams+Beta Lactamase inhibitors (BL+BLI) had significantly higher mortality as compared to patients treated with carbapenems. More data from multiple centres need to be gathered to formulate appropriate antibiotic policy for critically ill patients admitted from the community. Copyright © 2017 Elsevier Inc. All rights reserved.

Microbiological Aetiology, Epidemiology, and Clinical Profile of Prosthetic Joint Infections: Are Current Antibiotic Prophylaxis Guidelines Effective?

PubMed Central

Cheng, Allen C.; Buising, Kirsty L.; Choong, Peter F. M.

2012-01-01

Prosthetic joint infections remain a major complication of arthroplasty. At present, local and international guidelines recommend cefazolin as a surgical antibiotic prophylaxis at the time of arthroplasty. This retrospective cohort study conducted across 10 hospitals over a 3-year period (January 2006 to December 2008) investigated the epidemiology and microbiological etiology of prosthetic joint infections. There were 163 cases of prosthetic joint infection identified. From a review of the microbiological culture results, methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci were isolated in 45% of infections. In addition, polymicrobial infections, particularly those involving Gram-negative bacilli and enterococcal species, were common (36%). The majority (88%) of patients received cefazolin as an antibiotic prophylaxis at the time of arthroplasty. In 63% of patients in this cohort, the microorganisms subsequently obtained were not susceptible to the antibiotic prophylaxis administered. The results of this study highlight the importance of ongoing reviews of the local ecology of prosthetic joint infection, demonstrating that the spectrum of pathogens involved is broad. The results should inform empirical antibiotic therapy. This report also provokes discussion about infection control strategies, including changing surgical antibiotic prophylaxis to a combination of glycopeptide and cefazolin, to reduce the incidence of infections due to methicillin-resistant staphylococci. PMID:22314530

Biocontrol mechanism by root-associated Bacillus amyloliquefaciens FZB42 – a review

PubMed Central

Chowdhury, Soumitra Paul; Hartmann, Anton; Gao, XueWen; Borriss, Rainer

2015-01-01

Bacillus amyloliquefaciens subsp. plantarum FZB42 is a Gram-positive model bacterium for unraveling plant–microbe interactions in Bacilli. In addition, FZB42 is used commercially as biofertilizer and biocontrol agent in agriculture. Genome analysis of FZB42 revealed that nearly 10% of the FZB42 genome is devoted to synthesizing antimicrobial metabolites and their corresponding immunity genes. However, recent investigations in planta demonstrated that – except surfactin – the amount of such compounds found in vicinity of plant roots is relatively low, making doubtful a direct function in suppressing competing microflora including plant pathogens. These metabolites have been also suspected to induce changes within the rhizosphere microbial community, which might affect environment and plant health. However, sequence analysis of rhizosphere samples revealed only marginal changes in the root microbiome, suggesting that secondary metabolites are not the key factor in protecting plants from pathogenic microorganisms. On the other hand, adding FZB42 to plants compensate, at least in part, changes in the community structure caused by the pathogen, indicating an interesting mechanism of plant protection by beneficial Bacilli. Sub-lethal concentrations of cyclic lipopeptides and volatiles produced by plant-associated Bacilli trigger pathways of induced systemic resistance (ISR), which protect plants against attacks of pathogenic microbes, viruses, and nematodes. Stimulation of ISR by bacterial metabolites is likely the main mechanism responsible for biocontrol action of FZB42. PMID:26284057

Biocontrol mechanism by root-associated Bacillus amyloliquefaciens FZB42 - a review.

PubMed

Chowdhury, Soumitra Paul; Hartmann, Anton; Gao, XueWen; Borriss, Rainer

2015-01-01

Bacillus amyloliquefaciens subsp. plantarum FZB42 is a Gram-positive model bacterium for unraveling plant-microbe interactions in Bacilli. In addition, FZB42 is used commercially as biofertilizer and biocontrol agent in agriculture. Genome analysis of FZB42 revealed that nearly 10% of the FZB42 genome is devoted to synthesizing antimicrobial metabolites and their corresponding immunity genes. However, recent investigations in planta demonstrated that - except surfactin - the amount of such compounds found in vicinity of plant roots is relatively low, making doubtful a direct function in suppressing competing microflora including plant pathogens. These metabolites have been also suspected to induce changes within the rhizosphere microbial community, which might affect environment and plant health. However, sequence analysis of rhizosphere samples revealed only marginal changes in the root microbiome, suggesting that secondary metabolites are not the key factor in protecting plants from pathogenic microorganisms. On the other hand, adding FZB42 to plants compensate, at least in part, changes in the community structure caused by the pathogen, indicating an interesting mechanism of plant protection by beneficial Bacilli. Sub-lethal concentrations of cyclic lipopeptides and volatiles produced by plant-associated Bacilli trigger pathways of induced systemic resistance (ISR), which protect plants against attacks of pathogenic microbes, viruses, and nematodes. Stimulation of ISR by bacterial metabolites is likely the main mechanism responsible for biocontrol action of FZB42.

The Causes of Post-Operative Meningitis: The Comparison Of Gram-Negative and Gram-Positive Pathogens.

PubMed

Kurtaran, Behice; Kuscu, Ferit; Ulu, Aslihan; Inal, Ayse Seza; Komur, Suheyla; Kibar, Filiz; Cetinalp, Nuri Eralp; Ozsoy, Kerem Mazhar; Arslan, Yusuf Kemal; Aksu, Hasan Salih; Tasova, Yesim

2017-06-20

In this study, we aim to determine the microbiological etiology in critically ill neurosurgical patients with nosocomial meningitis (NM) and show the impact of Gram-negative rods and differences of patient's characteristics, clinical and prognostic measures between Gram-negative and Gram-positive meningitis. In this prospective, one center study we reviewed all adult patients hospitalized during a 12-year period and identified pathogens isolated from post-neurosurgical cases of NM. Demographic, clinical, and treatment characteristics were noted from the medical records. Of the 134 bacterial NM patients, 78 were male and 56 were female, with a mean age of 46±15.9 and median age of 50 (18-80) years. 141 strains isolated; 82 (58.2%) were Gram negative, 59 (41.8%) were Gram positive. Most common isolated microorganism was Acinetobacter baumannii (%34.8). In comparison of mortality data shows that the patients who have meningitis with Gram-negative pathogens have higher mortality than with Gram positives (p=0.034). The duration between surgery and meningitis was shorter in Gram negative meningitis cases compared to others (p=0.045) but the duration between the diagnosis and death was shorter in Gram-positive meningitis cases compared to Gram negatives (p= 0.017). CSF protein and lactate level were higher and glucose level was lower in cases of NM with Gram negatives (p value were respectively, 0.022, 0.039 and 0.049). As conclusions; in NM, Gram-negative pathogens were seen more frequently; A.baumanni was the predominant pathogen; and NM caused by Gram negatives had worse clinical and laboratory characteristic and prognostic outcome than Gram positives.

Cost of hospitalised patients due to complicated urinary tract infections: a retrospective observational study in countries with high prevalence of multidrug-resistant Gram-negative bacteria: the COMBACTE-MAGNET, RESCUING study.

PubMed

Vallejo-Torres, Laura; Pujol, Miquel; Shaw, Evelyn; Wiegand, Irith; Vigo, Joan Miquel; Stoddart, Margaret; Grier, Sally; Gibbs, Julie; Vank, Christiane; Cuperus, Nienke; van den Heuvel, Leo; Eliakim-Raz, Noa; Carratala, Jordi; Vuong, Cuong; MacGowan, Alasdair; Babich, Tanya; Leibovici, Leonard; Addy, Ibironke; Morris, Stephen

2018-04-12

Complicated urinary tract infections (cUTIs) impose a high burden on healthcare systems and are a frequent cause of hospitalisation. The aims of this paper are to estimate the cost per episode of patients hospitalised due to cUTI and to explore the factors associated with cUTI-related healthcare costs in eight countries with high prevalence of multidrug resistance (MDR). This is a multinational observational, retrospective study. The mean cost per episode was computed by multiplying the volume of healthcare use for each patient by the unit cost of each item of care and summing across all components. Costs were measured from the hospital perspective. Patient-level regression analyses were used to identify the factors explaining variation in cUTI-related costs. The study was conducted in 20 hospitals in eight countries with high prevalence of multidrug resistant Gram-negative bacteria (Bulgaria, Greece, Hungary, Israel, Italy, Romania, Spain and Turkey). Data were obtained from 644 episodes of patients hospitalised due to cUTI. The mean cost per case was €5700, with considerable variation between countries (largest value €7740 in Turkey; lowest value €4028 in Israel), mainly due to differences in length of hospital stay. Factors associated with higher costs per patient were: type of admission, infection source, infection severity, the Charlson comorbidity index and presence of MDR. The mean cost per hospitalised case of cUTI was substantial and varied significantly between countries. A better knowledge of the reasons for variations in length of stays could facilitate a better standardised quality of care for patients with cUTI and allow a more efficient allocation of healthcare resources. Urgent admissions, infections due to an indwelling urinary catheterisation, resulting in septic shock or severe sepsis, in patients with comorbidities and presenting MDR were related to a higher cost. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Multidrug-resistant gram-negative bacterial infections in a teaching hospital in Ghana.

PubMed

Agyepong, Nicholas; Govinden, Usha; Owusu-Ofori, Alex; Essack, Sabiha Yusuf

2018-01-01

Multidrug-resistant Gram-negative bacteria have emerged as major clinical and therapeutic dilemma in hospitals in Ghana.To describe the prevalence and profile of infections attributable to multidrug-resistant Gram-negative bacteria among patients at the Komfo Anokye Teaching Hospital in the Ashanti region of Ghana. Bacterial cultures were randomly selected from the microbiology laboratory from February to August, 2015. Bacterial identification and minimum inhibitory concentrations were conducted using standard microbiological techniques and the Vitek-2 automated system. Patient information was retrieved from the hospital data. Of the 200 isolates, consisting of K. pneumoniae , A. baumannii , P. aeruginosa , Enterobacter spp. , E. coli , Yersinia spp. , Proteus mirabilis , Pasteurella spp., Chromobacterium violaceum, Salmomella enterica , Vibrio spp. , Citrobacter koseri , Pantoea spp. , Serratia spp. , Providencia rettgeri Burkholderia cepacia , Aeromonas spp. , Cadecea lapagei and Sphingomonas paucimobilis , 101 (50.5%) and 99 (49.5%) recovered from male and female patients respectively The largest proportion of patients were from age-group ≥60 years (24.5%) followed by < 10 years (24.0%) and least 10-19 years (9.5%) with a mean patient age of 35.95 ± 27.11 (0.2-91) years. The decreasing order of specimen source was urine 97 (48.5%), wound swabs 47 (23.5%), sputum 22 (11.0%) bronchial lavage, nasal and pleural swabs 1 (0.50%). Urinary tract infection was diagnosed in 34.5% of patients, sepsis in 14.5%, wound infections (surgical and chronic wounds) in 11.0%, pulmonary tuberculosis in 9.0% and appendicitis, bacteremia and cystitis in 0.50%. The isolates showed high resistance to ampicillin (94.4%), trimethoprim/sulfamethoxazole (84.5%), cefuroxime (79.0%) and cefotaxime (71.3%) but low resistance to ertapenem (1.5%), meropenem (3%) and amikacin (11%). The average multi-drug resistance was 89.5%, and ranged from 53.8% in Enterobacter spp. to 100.0% in Acinetobacter spp. and P. aeruginosa . Bacterial infections caused by multi-drug resistant (isolates resistant to at least one agent in three or more antibiotic classes) Gram-negative pathogens among patients at Komfo Anokye Teaching Hospital in Kumasi, Ghana are rife and interventions are necessary for their containment.

Surveillance of multidrug resistant uropathogenic bacteria in hospitalized patients in Indian

PubMed Central

Mishra, Monali Priyadarsini; Debata, Nagen Kumar; Padhy, Rabindra Nath

2013-01-01

Objective To record surveillance, antibiotic resistance of uropathogens of hospitalized patients over a period of 18 months. Methods Urine samples from wards and cabins were used for isolating urinary tract infection (UTI)-causing bacteria that were cultured on suitable selective media and identified by biochemical tests; and their antibiograms were ascertained by Kirby-Bauer's disc diffusion method, in each 6-month interval of the study period, using 18 antibiotics of five different classes. Results From wards and cabins, 1 245 samples were collected, from which 996 strains of bacteria belonging to 11 species were isolated, during April 2011 to September 2012. Two Gram-positive, Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), and nine Gram-negative bacteria, Acinetobacter baumannii, Citrobacter sp., Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis, Proteus vulgaris and Pseudomonas aeruginosa were isolated. Both S. aureus and E. faecalis were vancomycin resistant, and resistant-strains of all pathogens increased in each 6-month period of study. Particularly, all Gram-negatives were resistant to nitrofurantoin and co-trimoxazole, the most preferred antibiotics of empiric therapy for UTI. Conclusions Antibiograms of 11 UTI-causing bacteria recorded in this study indicated moderately higher numbers of strains resistant to each antibiotic studied, generating the fear of precipitating fervent episodes in public health particularly with bacteria, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and S. aureus. Moreover, vancomycin resistance in strains of S. aureus and E. faecalis is a matter of concern. PMID:23620859

Intestinal volvulus with coagulative hepatic necrosis in a chicken.

PubMed

Haridy, Mohie; Goryo, Masanobu; Sasaki, Jun; Okada, Kosuke

2010-04-01

A 7-week-old SPF chicken inoculated at 4 weeks of age with chicken anemia virus was puffed up depressed and had ruffled feathers and a good body condition. Intestinal volvulus involving the jejunum and part of the duodenum forming two loops with one knob was observed. Microscopically, venous infarction of the obstructed loops, periportal and sublobular multifocal coagulative hepatic necrosis and granulomatous inflammation of the cecal tonsils were observed. Gram staining revealed no bacteria in hepatic tissue; however, gram-positive bacilli were detected in the necrotic debris in the intestinal lumen. Immunosuppression might have predisposed the chicken to intestinal and cecal tonsil infection that then progressed to volvulus. Loss of the mucosal barrier in infarction might allow bacterial toxins and vasoactive factors to escape into the systemic circulation (toxemia) and be responsible for the hepatic necrosis.

[Pneumonia caused byCorynebacterium pseudodiphtheriticum].

PubMed

Furiasse, Daniela; Gasparotto, Ana M; Monterisi, Aída; Castellano, Gabriela; Rocchi, Marta

Microorganisms of the genera Corynebacterium, specie pseudodiphtheriticum are a part of the indigenous microbiota of human skin and oropharinx. Nevertheless in recent decades these bacilli are emerging as opportunistic pathogens causing clinically significant infections in patients with previous compromise. We report the case of a 76 years old female patient, with a history of hypertension, hypothyroidism, type 2 diabetes and chronic renal failure, who presented pneumonia during their stay at the intensive care unit. The induced sputum revealed a representative sample with monomicrobial gram positive pleomorphic coryneform rods (Gram stain) and cultures demonstrated the presence of C. pseudodiphtheriticum as the only bacteria recovered. The pacient received an empirical third generation cephalosporin medication with a succesfull recovery. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

PIRATE project: point-of-care, informatics-based randomised controlled trial for decreasing overuse of antibiotic therapy in Gram-negative bacteraemia.

PubMed

Huttner, Angela; Albrich, Werner C; Bochud, Pierre-Yves; Gayet-Ageron, Angèle; Rossel, Anne; Dach, Elodie von; Harbarth, Stephan; Kaiser, Laurent

2017-07-13

Antibiotic overuse drives antibiotic resistance. The optimal duration of antibiotic therapy for Gram-negative bacteraemia (GNB), a common community and hospital-associated infection, remains unknown and unstudied via randomised controlled trials (RCTs). This investigator-initiated, multicentre, non-inferiority, informatics-based point-of-care RCT will randomly assign adult hospitalised patients receiving microbiologically efficacious antibiotic(s) for GNB to (1) 14 days of antibiotic therapy, (2) 7 days of therapy or (3) an individualised duration determined by clinical response and 75% reduction in peak C reactive protein (CRP) values. The randomisation will occur in equal proportions (1:1:1) on day 5 (±1) of efficacious antibiotic therapy as determined by antibiogram; patients, their physicians and study investigators will be blind to treatment duration allocation until the day of antibiotic discontinuation. Immunosuppressed patients and those with GNB due to complicated infections (endocarditis, osteomyelitis, etc) and/or non-fermenting bacilli ( Acinetobacter spp, Burkholderia spp, Pseudomonas spp) Brucella spp, Fusobacterium spp or polymicrobial growth with Gram-positive organisms will be ineligible. The primary outcome is incidence of clinical failure at day 30; secondary outcomes include clinical failure, all-cause mortality and incidence of Clostridiumdifficile infection in the 90-day study period. An interim safety analysis will be performed after the first 150 patients have been followed for ≤30 days. Given a chosen margin of 10%, the required sample size to determine non-inferiority is roughly 500 patients. Analyses will be performed on both intention-to-treat and per-protocol populations. Ethics approval was obtained from the cantonal ethics committees of all three participating sites. Results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal. This trial is registered at www.clinicaltrials.gov (NCT03101072; pre-results). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Non-species-specific effects of unacylated homoserine lactone and hexylresorcinol, low molecular weight autoregulators, on the growth and development of bacteria].

PubMed

Muliukin, A L; Filippova, S N; Kozlova, A N; Surgucheva, N A; Bogdanova, T I; Tsaplina, I A; El'-Registan, G I

2006-01-01

We conducted a comparative study of the effects of alpha-amino-gamma-butyrolactone, the common structural element of extracellular microbial regulators of the homoserine lactone (HSL) group, and of 4-n-hexylresorcinol, an autoregulator of the alkylhydroxybenzene (AHB) group, on the growth and development of gram-positive and gram-negative bacteria. We revealed non-species-specific effects of HSL and AHB and characterized their concentration dependencies. The addition of 10(-5)-10(-3) M HSL or 10(-5)-10(-4) M AHB during the exponential growth phase of the cultures grown on balanced media resulted in cell division arrest and accelerated the transition to the stationary phase that culminated in endospore formation in Bacillus cereus, Alicyclobacillus tolerans, and Sulfobacillus thermosulfidooxidans. When bacilli grew under the cultivation conditions that resulted in a low-zero spore percentage, 10(-4)-10(-3) M HSL cancelled the inhibition of spore formation. In the gram-negative bacteria Pseudomonas aurantiaca and Azotobacter vinelandii, AHB at concentrations of 10(-4) to (1.5-2.5) 10(-4) M induced the formation of dormant cells. Studies with the actinobacterium Streptomyces avermitilis revealed that the HSL effect varied depending on the age of the test cultures. The addition of 10(-4) M HSL during the lag phase of a submerged streptomycete culture accelerated its transition to the stationary phase and induced the formation of endospores, the dormant cells that are regarded as alternatives to exospores (conidia). If HSL (3.64 and 4.55 mg per 1cm2 disc) was locally added to a surface S. avermitilis culture, the growing mycelium formed rings that differed in their density, in the extent of the development of aerial mycelium, and in the presence/absence of exospores. Ring-shaped growth of streptomycete mycelia was also induced by 0.075-0.75 mg of AHB; however, unlike HSL, AHB repressed exospore formation. The data on non-species-specific effects of HSL and AHB suggest that they may perform regulatory functions on the microbial community level.

[Multi-resistant microorganisms: Acinetobacter. Nursing care].

PubMed

Milà Enrique, A; Barbeito Zaldúa, N; Paunellas Albert, J; Castillejo Badia, N

1997-09-01

There has recently been an increase in the incidence of bacteria that are resistant to a variety of medications. Acinetobactor, a gram-negative bacillus, is one that appears most often. This microbe, which has two subspecies, can be carried in the blood of one fourth of the healthy population. It manifests itself pathologically in hospital situations in which the patient becomes gravely ill. The principle infections it can provoke are: meningitis, endocarditis, pneumonia, urinary tract infections, bacteriemia, etc. Treatment is dependent upon antibacterial sensibility tests. As in the case of all microorganisms, prevention of infection is absolutely imperative to stop the spread of this very dangerous bacteria.

[Etiology of acute and chronic pyelonephritis in children in Khabarovsk region].

PubMed

Kozlova, E A; Kholodok, G N; Alekseeva, I N; Kozlov, V K

2008-01-01

Microflora of urinary tract was studied in 419 children aged 1 - 17 years and hospitalized due to acute or chronic pyelonephritis. Etiology of inflammatory process was established in 57.8% of cases. According to our study, etiologic structure of causative agents of pyelonephritis did not differ from all-Russian data. The leading positions belonged to Gram-negative microorganisms from Enterobacteriaceae family: Escherichia coli, Proteus mirabilis, and Klebsiella spp. Results of the study point to high susceptibility of main causative agents of pyelonephritis to cephalosporins, aminoglycosides, and fluoroquinolones. High resistance to aminopenicillines was noted. In several isolates from Enterobacteriaceae family significant resistance to nalidixic acid and furazidin was observed.

Native Valve Endocarditis Due to Citrobacter Chronic Prostatitis

PubMed Central

Lum, Corey; Bolger, Dennis; Bello, Erlaine

2014-01-01

Introduction: Citrobacter koseri is a gram-negative bacillus that rarely causes infection in immunocompetent hosts and typically is associated with urinary or respiratory tract infections. Rarely will Citrobacter be a cause of infective endocarditis. Case Report: We present a case of a 77-year-old man with no known immunocompromising conditions who was hospitalized for infective aortic endocarditis due to Citrobacter koseri originating from a chronically infected prostate. Unusually, he also developed a C. koseri diskitis and phlegmon, which, along with the aortic vegetations, increased in size despite appropriate antibiotics. The patient thus met indications for aortic valve replacement and had improved appearance of lesions in follow-up imaging.

Associations Between Enteral Colonization With Gram-Negative Bacteria and Intensive Care Unit-Acquired Infections and Colonization of the Respiratory Tract.

PubMed

Frencken, Jos F; Wittekamp, Bastiaan H J; Plantinga, Nienke L; Spitoni, Cristian; van de Groep, Kirsten; Cremer, Olaf L; Bonten, Marc J M

2018-02-01

Enteral and respiratory tract colonization with gram-negative bacteria may lead to subsequent infections in critically ill patients. We aimed to clarify the interdependence between gut and respiratory tract colonization and their associations with intensive care unit (ICU)-acquired infections in patients receiving selective digestive tract decontamination (SDD). Colonization status of the rectum and respiratory tract was determined using twice-weekly microbiological surveillance in mechanically ventilated subjects receiving SDD between May 2011 and June 2015 in a tertiary medical-surgical ICU in the Netherlands. Acquisition of infections was monitored daily by dedicated observers. Marginal structural models were used to determine the associations between gram-negative rectal colonization and respiratory tract colonization, ICU-acquired gram-negative infection, and ICU-acquired gram-negative bacteremia. Among 2066 ICU admissions, 1157 (56.0%) ever had documented gram-negative carriage in the rectum during ICU stay. Cumulative incidences of ICU-acquired gram-negative infection and bacteremia were 6.0% (n = 124) and 2.1% (n = 44), respectively. Rectal colonization was an independent risk factor for both respiratory tract colonization (cause-specific hazard ratio [CSHR], 2.93 [95% confidence interval {CI}, 2.02-4.23]) and new gram-negative infection in the ICU (CSHR, 3.04 [95% CI, 1.99-4.65]). Both rectal and respiratory tract colonization were associated with bacteremia (CSHR, 7.37 [95% CI, 3.25-16.68] and 2.56 [95% CI, 1.09-6.03], respectively). Similar associations were observed when Enterobacteriaceae and glucose nonfermenting gram-negative bacteria were analyzed separately. Gram-negative rectal colonization tends to be stronger associated with subsequent ICU-acquired gram-negative infections than gram-negative respiratory tract colonization. Gram-negative rectal colonization seems hardly associated with subsequent ICU-acquired gram-negative respiratory tract colonization. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Carbapenem stewardship: positive impact on hospital ecology.

PubMed

Lima, Ana Lucia Lei Munhoz; Oliveira, Priscila Rosalba Domingos de; Paula, Adriana Pereira de; Dal-Paz, Karine; Almeida, João Nóbrega de; Félix, Cássia da Silva; Rossi, Flávia

2011-01-01

Excessive group 2 carbapenem use may result in decreased bacterial susceptibility. We evaluated the impact of a carbapenem stewardship program, restricting imipenem and meropenem use. Ertapenem was mandated for ESBL-producing Enterobacteriaceae infections in the absence of non-fermenting Gram-negative bacilli (GNB) from April 2006 to March 2008. Group 2 carbapenems were restricted for use against GNB infections susceptible only to carbapenems and suspected GNB infections in unstable patients. Cumulative susceptibility tests were done for nosocomial pathogens before and after restriction using Clinical and Laboratory Standards Institute (CLSI) guide-lines.Vitek System or conventional identification methods were performed and susceptibility testing done by disk diffusion according to CLSI.Antibiotic consumption (t-test) and susceptibilities (McNemar's test) were determined. The defined daily doses (DDD) of group 2 carbapenems declined from 61.1 to 48.7 DDD/1,000 patient-days two years after ertapenem introduction (p = 0.027). Mean ertapenem consumption after restriction was 31.5 DDD/1,000 patient-days. Following ertapenem introduction no significant susceptibility changes were noticed among Gram-positive cocci. The most prevalent GNB were P. aeruginosa, Klebsiella pneumoniae, and Acinetobacter spp. There was no change in P. aeruginosa susceptibility to carbapenems. Significantly improved P. aeruginosa and K. pneumoniae ciprofloxacin susceptibilities were observed, perhaps due to decreased group 2 carbapenem use. K. pneumoniae susceptibility to trimethoprim-sulfamethoxazole improved. Preferential use of ertapenem resulted in reduced group 2 carbapenem use, with a positive impact on P. aeruginosa and K. pneumoniae susceptibility.

UTI diagnosis and antibiogram using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Kyriakides, Alexandros; Hadjigeorgiou, Katerina; Pitris, Constantinos

2009-07-01

Urinary tract infection diagnosis and antibiogram require a 48 hour waiting period using conventional methods. This results in ineffective treatments, increased costs and most importantly in increased resistance to antibiotics. In this work, a novel method for classifying bacteria and determining their sensitivity to an antibiotic using Raman spectroscopy is described. Raman spectra of three species of gram negative Enterobacteria, most commonly responsible for urinary tract infections, were collected. The study included 25 samples each of E.coli, Klebsiella p. and Proteus spp. A novel algorithm based on spectral ratios followed by discriminant analysis resulted in classification with over 94% accuracy. Sensitivity and specificity for the three types of bacteria ranged from 88-100%. For the development of an antibiogram, bacterial samples were treated with the antibiotic ciprofloxacin to which they were all sensitive. Sensitivity to the antibiotic was evident after analysis of the Raman signatures of bacteria treated or not treated with this antibiotic as early as two hours after exposure. This technique can lead to the development of new technology for urinary tract infection diagnosis and antibiogram with same day results, bypassing urine cultures and avoiding all undesirable consequences of current practice.

Complicated catheter-associated urinary tract infections due to Escherichia coli and Proteus mirabilis.

PubMed

Jacobsen, S M; Stickler, D J; Mobley, H L T; Shirtliff, M E

2008-01-01

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options.

Complicated Catheter-Associated Urinary Tract Infections Due to Escherichia coli and Proteus mirabilis

PubMed Central

Jacobsen, S. M.; Stickler, D. J.; Mobley, H. L. T.; Shirtliff, M. E.

2008-01-01

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options. PMID:18202436

Evolving Understanding of the Causes of Pneumonia in Adults, With Special Attention to the Role of Pneumococcus.

PubMed

Musher, Daniel M; Abers, Michael S; Bartlett, John G

2017-10-30

Before 1945, Streptococcus pneumoniae caused more than 90% of cases of pneumonia in adults. After 1950, the proportion of pneumonia caused by pneumococcus began to decline. Pneumococcus has continued to decline; at present, this organism is identified in fewer than fewer10%-15% of cases. This proportion is higher in Europe, a finding likely related to differences in vaccination practices and smoking. Gram-negative bacilli, Staphylococcus aureus, Chlamydia, Mycoplasma, and Legionella are each identified in 2%-5% of patients with pneumonia who require hospitalization. Viruses are found in 25% of patients, up to one-third of these have bacterial coinfection. Recent studies fail to identify a causative organism in more than 50% of cases, which remains the most important challenge to understanding lower respiratory infection. Our findings have important implications for antibiotic stewardship and should be considered as new policies for empiric pneumonia management are developed. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Bacterial profile in primary teeth with necrotic pulp and periapical lesions.

PubMed

da Silva, Léa Assed Bezerra; Nelson-Filho, Paulo; Faria, Gisele; de Souza-Gugelmin, Maria Cristina Monteiro; Ito, Izabel Yoko

2006-01-01

The objective of this study was to evaluate the bacterial profile in root canals of human primary teeth with necrotic pulp and periapical lesions using bacterial culture. A total of 20 primary teeth with necrotic pulp and radiographically visible radiolucent areas in the region of the bone furcation and/or the periapical region were selected. After crown access, 4 sterile absorbent paper points were introduced sequentially into the root canal for collection of material. After 30 s, the paper points were removed and placed in a test tube containing reduced transport fluid (RTF) and were sent for microbiological evaluation. Anaerobic microorganisms were found in 100% of the samples, black-pigmented bacilli in 30%, aerobic microorganisms in 60%, streptococci in 85%, gram-negative aerobic rods in 15% and staphylococci were not quantified. Mutans streptococci were found in 6 root canals (30%), 5 canals with Streptococcus mutans and 1 canal with Streptococcus mutans and Streptococcus sobrinus. It was concluded that in root canals of human primary teeth with necrotic pulp and periapical lesions, the infection is polymicrobial with predominance of anaerobic microorganisms.

The importance of soap selection for routine hand hygiene in hospital.

PubMed Central

Ojajärvi, J.

1981-01-01

Five different types of liquid soap were studied in hospital wards, each during two months' use. Altogether 1306 finger print samples were taken from the hands of the staff by sampling twice a week and the acceptability of the soaps was measured by a questionnaire. During the use of different soaps only slight differences were found in the numbers of total bacteria or in the occurrence of Staph. aureus and gram-negative bacilli on the hands. During the use of the emulsion-type product studied, several persons who had dermatological problems had lower mean bacterial counts of the fingers than during the use of the other soaps. This soap was also favourably accepted by the staff. After over one year's use of pine oil soap and alcohol, the staff of the hospital was satisfied with the method. However, several persons with skin problems admitted to not using soap or alcohol. The considerable differences found in the acceptability of soaps imply that for use in hospital the choice of a soap acceptable to the nursing staff is important in promoting proper hand hygiene. PMID:7240731

Rhodotorula glutinis meningitis: a case report and review of literature.

PubMed

Menon, Sarala; Gupta, H R; Sequeira, R; Chavan, Shazia; Gholape, D; Amandeep, S; Bhilave, N; Chowdhary, A S

2014-07-01

Rhodotorula is ubiquitous saprophytic yeast belonging to phylum Basidiomycota. These encapsulated basidiomycetes are being increasingly recognised as important emerging human pathogens. There are scanty reports of meningitis caused by Rhodurorula spp in HIV infected patients. We present one such case of meningitis by Rhodutorula glutinis in HIV-infected patient. The patient also had a past history of abdominal tuberculosis. The diagnosis of Rhodotorula was confirmed by Gram staining and culture of the cerebrospinal fluid (CSF). Contamination was ruled out by repeated culturing of CSF from the same patient. Therapy with Amphotericin B showed good results. Patient was discharged from the hospital. However, in the seventh month of follow-up patient was readmitted with complaints of fever, breathlessness, altered sensorium, vomiting and succumbed to his illness. This time the CSF cultures remained negative for Rhodotorula, acid fast bacilli and other pyogenic organisms. Our last 11-year retrospective analysis of 8197 specimens received for mycological work-up showed that this is the first report of R. glutinis isolation from our institute. © 2014 Blackwell Verlag GmbH.

Emerging drugs in sepsis.

PubMed

Leone, Marc; Textoris, Julien; Michel, Fabrice; Wiramus, Sandrine; Martin, Claude

2010-03-01

Sepsis remains a major cause of death in intensive care units. Despite an intense research, a new drug that is effective in reducing mortality in sepsis is still awaited. The literature was analyzed with Pubmed() during the 2008 - 2009 period. If required, seminal articles published before 2008 were cited. Clinical trials focusing on 'sepsis' were first assessed. Next, relevant experimental data in this field were reported. The goal of the review is to determine the role for new licensed antibiotics, to give an insight into the conflict on adjuvant therapies and to disclose new experimental concepts. New licensed antibiotics will offer the opportunity to refine the treatment choices. Direct hemoperfusion using polymyxin B-immobilized fiber column may be an option in sepsis due to Gram-negative bacilli. Among non-antibiotic drugs, new ongoing studies will clarify the role of drotrecogin alfa (activated) and low dose hydrocortisone. The modulation of monocytic human leukocyte antigen-DR seems the most prominent treatment. The use of cardiovascular drugs requires well-conducted clinical trials. The regulation of high mobility group box 1, adenosine blockade or correction of the impaired energy production is still at the experimental level.

The effect of a changed environment on bacterial colonization rates in an established burns centre

PubMed Central

Wormald, P. J.

1970-01-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old. In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit. PMID:4993291

The effect of a changed environment on bacterial colonization rates in an established burns centre.

PubMed

Wormald, P J

1970-12-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old.In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit.

Hypervirulent (hypermucoviscous) Klebsiella pneumoniae

PubMed Central

Shon, Alyssa S.; Bajwa, Rajinder P.S.; Russo, Thomas A.

2013-01-01

A new hypervirulent (hypermucoviscous) variant of Klebsiella pneumoniae has emerged. First described in the Asian Pacific Rim, it now increasingly recognized in Western countries. Defining clinical features are the ability to cause serious, life-threatening community-acquired infection in younger healthy hosts, including liver abscess, pneumonia, meningitis and endophthalmitis and the ability to metastatically spread, an unusual feature for enteric Gram-negative bacilli in the non-immunocompromised. Despite infecting a healthier population, significant morbidity and mortality occurs. Although epidemiologic features are still being defined, colonization, particularly intestinal colonization, appears to be a critical step leading to infection. However the route of entry remains unclear. The majority of cases described to date are in Asians, raising the issue of a genetic predisposition vs. geospecific strain acquisition. The traits that enhance its virulence when compared with “classical” K. pneumoniae are the ability to more efficiently acquire iron and perhaps an increase in capsule production, which confers the hypermucoviscous phenotype. An objective diagnostic test suitable for routine use in the clinical microbiology laboratory is needed. If/when these strains become increasingly resistant to antimicrobials, we will be faced with a frightening clinical scenario. PMID:23302790

Infectious crystalline keratopathy associated with Klebsiella oxytoca.

PubMed

Chou, Timothy Y; Adyanthaya, Rohit

2012-12-01

The purpose of this study is to report a novel case of a Klebsiella oxytoca-associated infectious crystalline keratopathy This is a case report study. An 80-year-old woman presented with complaint of noticing a white spot in the left eye for 2 to 3 days, as well as mild soreness and discharge. Past ocular history was notable for a failed left corneal transplant for which she was taking prednisolone acetate 1 % twice per day. On slit-lamp examination, there was an extensive stromal ulcer and infiltrate in the inferior half of the transplant. Extending superiorly in the graft were branching, needle-like deep stromal opacities, characteristic of infectious crystalline keratopathy. Diagnostic scrapings revealed Gram-negative bacilli, subsequently identified on culture as K. oxytoca. There was also light growth of Staphylococcus species. The patient was placed on double topical antibiotic therapy with moxifloxacin and fortified tobramycin. After 2 months of treatment there was gradual resolution of the infection. K. oxytoca is a microorganism which can be associated with clinical infectious crystalline keratopathy, presenting as a mixed infection along with Staphylococcus species.

Gram staining for the treatment of peritonsillar abscess.

PubMed

Takenaka, Yukinori; Takeda, Kazuya; Yoshii, Tadashi; Hashimoto, Michiko; Inohara, Hidenori

2012-01-01

Objective. To examine whether Gram staining can influence the choice of antibiotic for the treatment of peritonsillar abscess. Methods. Between 2005 and 2009, a total of 57 cases of peritonsillar abscess were analyzed with regard to cultured bacteria and Gram staining. Results. Only aerobes were cultured in 16% of cases, and only anaerobes were cultured in 51% of cases. Mixed growth of aerobes and anaerobes was observed in 21% of cases. The cultured bacteria were mainly aerobic Streptococcus, anaerobic Gram-positive cocci, and anaerobic Gram-negative rods. Phagocytosis of bacteria on Gram staining was observed in 9 cases. The bacteria cultured from these cases were aerobic Streptococcus, anaerobic Gram-positive cocci, and anaerobic Gram-negative rods. The sensitivity of Gram staining for the Gram-positive cocci and Gram-negative rods was 90% and 64%, respectively. The specificity of Gram staining for the Gram-positive cocci and Gram-negative rods was 62% and 76%, respectively. Most of the Gram-positive cocci were sensitive to penicillin, but some of anaerobic Gram-negative rods were resistant to penicillin. Conclusion. When Gram staining shows only Gram-positive cocci, penicillin is the treatment of choice. In other cases, antibiotics effective for the penicillin-resistant organisms should be used.

Clostridium perfringens type A fatal acute hemorrhagic gastroenteritis in a dog

PubMed Central

Schlegel, Ben J.; Van Dreumel, Tony; Slavić, Durda; Prescott, John F.

2012-01-01

The morning after participating in a dog show, a 2-year-old Pomeranian dog was found dead in a pool of bloody feces. Necropsy revealed hemorrhagic gastroenteritis of the entire gastrointestinal tract, with many Gram-positive bacilli on the surface and in the lumen and crypts of the intestine. Enterotoxin-positive type A Clostridium perfringens were isolated in large numbers. This dramatic case of fatal C. perfringens gastroenteritis highlights the need to better understand the role of this bacterium in enteric disease of dogs. PMID:23115371

Monomicrobial necrotizing fasciitis in a single center: the emergence of Gram-negative bacteria as a common pathogen.

PubMed

Yahav, D; Duskin-Bitan, H; Eliakim-Raz, N; Ben-Zvi, H; Shaked, H; Goldberg, E; Bishara, J

2014-11-01

Necrotizing fasciitis (NF) is a life-threatening soft tissue infection. It is usually caused by Streptococcus pyogenes and other Gram-positive bacteria. Several reports, however, emphasize the importance of Gram-negative rods in this infection. We retrospectively studied all cases of monomicrobial necrotizing fasciitis hospitalized in our center during the years 2002-2012. We compared clinical characteristics and outcomes of patients with Gram-negative versus Gram-positive infection. Forty-five cases were reviewed, 19 caused by Gram-negative organisms, 10 of them Escherichia coli, and 26 caused by Gram-positive organisms, 10 of them S. pyogenes. Compared to Gram-positive infections, patients with Gram-negative infections were more likely to have a baseline malignancy (9/19, 47.4%) or to have undergone recent surgery (4/19, 42.3%). The 30-day mortality was higher among Gram-negative infected patients (8/19, 42.1% vs. 8/26, 30.8%). Creatine phosphokinase (CPK) was elevated in a minority of patients with Gram-negative necrotizing fasciitis, and its absolute value was lower than in Gram-positive necrotizing fasciitis. In our center, 42% of monomicrobial necrotizing fasciitis cases were found to be caused by Gram-negative organisms, mostly E. coli. These infections usually appeared in immunocompromised or postoperative patients, often presented with normal CPK levels, and were associated with high mortality rates.

Gram-negative diabetic foot osteomyelitis: risk factors and clinical presentation.

PubMed

Aragón-Sánchez, Javier; Lipsky, Benjamin A; Lázaro-Martínez, Jose L

2013-03-01

Osteomyelitis frequently complicates infections in the feet of patients with diabetes. Gram-positive cocci, especially Staphylococcus aureus, are the most commonly isolated pathogens, but gram-negative bacteria also cause some cases of diabetic foot osteomyelitis (DFO). These gram-negatives require different antibiotic regimens than those commonly directed at gram-positives. There are, however, few data on factors related to their presence and how they influence the clinical picture. We conducted a retrospective study to determine the variables associated with the isolation of gram-negative bacteria from bone samples in cases of DFO and the clinical presentation of these infections. Among 341 cases of DFO, 150 had a gram-negative isolate (alone or combined with a gram-positive isolate) comprising 44.0% of all patients and 50.8% of those with a positive bone culture. Compared with gram-positive infections, wounds with gram-negative organisms more often had a fetid odor, necrotic tissue, signs of soft tissue infection accompanying osteomyelitis, and clinically severe infection. By multivariate analysis, the predictive variables related to an increased likelihood of isolating gram-negatives from bone samples were glycated hemoglobin <7% (odds ratio [OR] = 2.0, 95% confidence interval [CI] = 1.1-3.5) and a wound caused by traumatic injury (OR = 2.0, 95% CI = 1.0-3.9). Overall, patients whose bone samples contained gram-negatives had a statistically significantly higher prevalence of leukocytosis and higher white blood cell counts than those without gram-negatives. In conclusion, gram-negative organisms were isolated in nearly half of our cases of DFO and were associated with more severe infections, higher white blood cell counts, lower glycated hemoglobin levels, and wounds of traumatic etiology.

Comparative activity of ceftobiprole against Gram-positive and Gram-negative isolates from Europe and the Middle East: the CLASS study.

PubMed

Rossolini, Gian M; Dryden, Matthew S; Kozlov, Roman S; Quintana, Alvaro; Flamm, Robert K; Läuffer, Jörg M; Lee, Emma; Morrissey, Ian; CLASS Study Group

2011-01-01

to assess the in vitro activity of ceftobiprole and comparators against a recent collection of Gram-positive and Gram-negative pathogens, in order to detect potential changes in susceptibility patterns, and to evaluate the Etest assay for ceftobiprole susceptibility testing. contemporary Gram-positive and Gram-negative isolates (excluding extended-spectrum β-lactamase-producing isolates) from across Europe and the Middle East were collected, and their susceptibility to ceftobiprole, vancomycin, teicoplanin, linezolid, ceftazidime and cefepime was assessed using the Etest method. Quality testing [using Etest and broth microdilution (BMD)] was conducted at a central reference laboratory. some 5041 Gram-positive and 4026 Gram-negative isolates were included. Against Gram-positive isolates overall, ceftobiprole had the lowest MIC50 (0.5 mg/L), compared with 1 mg/L for its comparators (vancomycin, teicoplanin and linezolid). Against methicillin-resistant Staphylococcus aureus, all four agents had a similar MIC90 (2 mg/L), but ceftobiprole had a 4-fold better MIC90 (0.5 mg/L) against methicillin-susceptible strains. Only 38 Gram-positive isolates were confirmed as ceftobiprole resistant. Among Gram-negative strains, 86.9%, 91.7% and 95.2% were susceptible to ceftobiprole, ceftazidime and cefepime, respectively. Pseudomonas aeruginosa was less susceptible to all three antimicrobials than any other Gram-negative pathogen. There was generally good agreement between local Etest results and those obtained at the reference laboratory (for ceftobiprole: 86.8% with Gram-negatives; and 94.7% with Gram-positives), as well as between results obtained by BMD and Etest methods (for ceftobiprole: 98.2% with Gram-negatives; and 98.4% with Gram-positives). ceftobiprole exhibits in vitro activity against a wide range of Gram-positive and Gram-negative pathogens, including multidrug-resistant strains. No changes in its known susceptibility profile were identified.

Antibacterial and antifungal activities of different parts of Tribulus terrestris L. growing in Iraq

PubMed Central

Al-Bayati, Firas A.; Al-Mola, Hassan F.

2008-01-01

Antimicrobial activity of organic and aqueous extracts from fruits, leaves and roots of Tribulus terrestris L., an Iraqi medicinal plant used as urinary anti-infective in folk medicine, was examined against 11 species of pathogenic and non-pathogenic microorganisms: Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Corynebacterium diphtheriae, Escherichia coli, Proteus vulgaris, Serratia marcescens, Salmonella typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans using microdilution method in 96 multiwell microtiter plates. All the extracts from the different parts of the plant showed antimicrobial activity against most tested microorganisms. The most active extract against both Gram-negative and Gram-positive bacteria was ethanol extract from the fruits with a minimal inhibitory concentration (MIC) value of 0.15 mg/ml against B. subtilis, B. cereus, P. vulgaris and C. diphtheriae. In addition, the same extract from the same plant part demonstrated the strongest antifungal activity against C. albicans with an MIC value of 0.15 mg/ml. PMID:18257138

Exogenous alanine and/or glucose plus kanamycin kills antibiotic-resistant bacteria.

PubMed

Peng, Bo; Su, Yu-Bin; Li, Hui; Han, Yi; Guo, Chang; Tian, Yao-Mei; Peng, Xuan-Xian

2015-02-03

Multidrug-resistant bacteria are an increasingly serious threat to human and animal health. However, novel drugs that can manage infections by multidrug-resistant bacteria have proved elusive. Here we show that glucose and alanine abundances are greatly suppressed in kanamycin-resistant Edwardsiella tarda by GC-MS-based metabolomics. Exogenous alanine or glucose restores susceptibility of multidrug-resistant E. tarda to killing by kanamycin, demonstrating an approach to killing multidrug-resistant bacteria. The mechanism underlying this approach is that exogenous glucose or alanine promotes the TCA cycle by substrate activation, which in turn increases production of NADH and proton motive force and stimulates uptake of antibiotic. Similar results are obtained with other Gram-negative bacteria (Vibrio parahaemolyticus, Klebsiella pneumoniae, Pseudomonas aeruginosa) and Gram-positive bacterium (Staphylococcus aureus), and the results are also reproduced in a mouse model for urinary tract infection. This study establishes a functional metabolomics-based strategy to manage infection by antibiotic-resistant bacteria. Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical and antimicrobial studies on the essential oil from Salvia santolinifolia Boiss.

PubMed

Nadir, Muhammad; Rasheed, Munawwer; Sherwani, Sikandar Khan; Kazmi, Shahana Urooj; Ahmad, Viqar Uddin

2013-01-01

In view of the reputation of genus Salvia in folklore medicine and its abundance in our region, the chemical composition and antimicrobial activity of essential oil from S. santolinifolia Boiss. was analyzed. Chemical analysis, using gas chromatography and gas chromatography mass spectrometry, retention indices and C-13 nuclear magnetic resonance spectroscopy has resulted in identification of 116 constituents, comprising about 97% of the total constituents. Out of these 116, 78 constituents are hitherto unreported from this source. The species belongs to α-pinene chemotype. In antibacterial assay, gram negative gastropathogens (Shigella boydii, S. flexneri, S. dysenteriae, Vibrio cholerae); causative agent of urinary tract infection (Proteus mirabilis and P. vulgaris) and pneumonia (Klebsiella pneumoniae) were found sensitive to this essential oil while Corynebacteria species and Staphylococcus epidermidis were significantly inhibited in antibacterial assay against gram positive bacteria. Clinical and Laboratory Standards Institute protocol was used for determining antimicrobial activity. Thus the essential oil from this species can be utilized as potential chemotherapeutic agent.

Bacterial Infections in Acute-on-Chronic Liver Failure.

PubMed

Yang, Lingling; Wu, Tianzhou; Li, Jiang; Li, Jun

2018-05-01

Acute-on-chronic liver failure (ACLF) is a newly recognized clinical syndrome characterized by preexisting chronic liver disease or cirrhosis with organ failure and high 28-day mortality (50-90%). Bacterial infections (BIs) play pivotal roles in the development and progression of ACLF either as a main precipitating event or a specific complication. The main organisms isolated as triggering ACLF are Gram-positive bacteria, followed by Gram-negative bacteria. Spontaneous bacterial peritonitis, pneumonia, urinary tract infections, and skin infections are prevalent infections that trigger and complicate ACLF. Despite appropriate antibiotic treatment, BIs account for poor ACLF outcomes and lead to a worse clinical course and higher intensive care unit admission and short-term mortality. Early diagnosis and novel nonantibiotic methods are highly important for managing BIs. Thus, this review focuses on the epidemiology, prognosis, and diagnosis of and management strategies for BIs in ACLF patients as well as the relationship between BIs and ACLF. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Antivirulence C-Mannosides as Antibiotic-Sparing, Oral Therapeutics for Urinary Tract Infections.

PubMed

Mydock-McGrane, Laurel; Cusumano, Zachary; Han, Zhenfu; Binkley, Jana; Kostakioti, Maria; Hannan, Thomas; Pinkner, Jerome S; Klein, Roger; Kalas, Vasilios; Crowley, Jan; Rath, Nigam P; Hultgren, Scott J; Janetka, James W

2016-10-27

Gram-negative uropathogenic Escherichia coli (UPEC) bacteria are a causative pathogen of urinary tract infections (UTIs). Previously developed antivirulence inhibitors of the type 1 pilus adhesin, FimH, demonstrated oral activity in animal models of UTI but were found to have limited compound exposure due to the metabolic instability of the O-glycosidic bond (O-mannosides). Herein, we disclose that compounds having the O-glycosidic bond replaced with carbon linkages had improved stability and inhibitory activity against FimH. We report on the design, synthesis, and in vivo evaluation of this promising new class of carbon-linked C-mannosides that show improved pharmacokinetic (PK) properties relative to O-mannosides. Interestingly, we found that FimH binding is stereospecifically modulated by hydroxyl substitution on the methylene linker, where the R-hydroxy isomer has a 60-fold increase in potency. This new class of C-mannoside antagonists have significantly increased compound exposure and, as a result, enhanced efficacy in mouse models of acute and chronic UTI.

Aerococcus urinae in urinary tract infections.

PubMed

Zhang, Q; Kwoh, C; Attorri, S; Clarridge, J E

2000-04-01

Aerococcus urinae is a rarely reported pathogen, possibly due to difficulties in the identification of the organism. A. urinae is a gram-positive coccus that grows in pairs and clusters, produces alpha-hemolysis on blood agar, and is negative for catalase and pyrrolidonyl aminopeptidase. Some of these characteristics and its being absent from the databases of most commercial identification systems could allow A. urinae to be misidentified as a streptococcus, enterococcus, or staphylococcus. We report two cases of urinary tract infection (UTI) caused by A. urinae and characterize these isolates by morphology, biochemical testing, whole-cell fatty acid analysis, 16S rRNA gene sequencing, and antibiotic susceptibilities. Most patients infected with A. urinae are elderly males with predisposing conditions who present initially with UTI. Because A. urinae is resistant to sulfonamides, treatment could be inappropriate, with infections resulting in serious complications, including death. It is important for the clinician and the microbiologist to consider A. urinae a potential pathogen and proceed with thorough microbiological identification.

Primary tuberculosis of glans penis after intravesical Bacillus Calmette Guerin immunotherapy.

PubMed

Sharma, V K; Sethy, P K; Dogra, P N; Singh, Urvashi; Das, P

2011-01-01

A 55-year-old male with carcinoma in situ of urinary bladder was treated with weekly intravesical injections of Bacillus Calmette Guerin (BCG) vaccine. Three days after the sixth injection, he developed low grade fever and multiple grouped punched out, 2-3 mm ulcers around meatus and corona glandis. In addition, multiple, firm, indurated, nontender papules and few deeper nodules were present on the proximal part of glans penis, along with bilateral enlarged, matted and nontender inguinal lymph nodes. There was no history suggestive of sexually transmitted diseases and high risk behavior. Chest X-ray was within normal limits, and Mantoux, Venereal Disease Research Laboratory (VDRL) and HIV antibody tests were negative. The biopsy from the penile ulcer revealed epithelioid cell granuloma with Langhans giant cells. Fine needle aspiration cytology from the lymph node also revealed epithelioid cell granuloma and acid fast bacilli on Ziehl Neelsen's stain. The tissue biopsy grew Mycobacterium tuberculosis. The BCG immunotherapy was stopped and patient was treated with four drug antitubercular therapy with isoniazid, rifampicin, ethambutol, and pyrazinamide in standard daily doses along with pyridoxine. The edema resolved and the ulcers started healing within 2 weeks, and at 6 weeks after starting antitubercular therapy almost complete healing occurred. To the best of our knowledge, we describe the first case of an Indian patient with BCG induced primary tuberculosis of penis after immunotherapy for carcinoma urinary bladder and review the previously described cases to increase awareness of this condition in dermatologists and venereologists.

TRIF Licenses Caspase-11-Dependent NLRP3 Inflammasome Activation by Gram-Negative Bacteria

PubMed Central

Rathinam, Vijay A.K.; Vanaja, Sivapriya Kailasan; Waggoner, Lisa; Sokolovska, Anna; Becker, Christine; Stuart, Lynda M.; Leong, John M.; Fitzgerald, Katherine A.

2013-01-01

SUMMARY Systemic infections with Gram-negative bacteria are characterized by high mortality rates due to the “sepsis syndrome,” a widespread and uncontrolled inflammatory response. Though it is well recognized that the immune response during Gram-negative bacterial infection is initiated after the recognition of endotoxin by Toll-like receptor 4, the molecular mechanisms underlying the detrimental inflammatory response during Gram-negative bacteremia remain poorly defined. Here, we identify a TRIF pathway that licenses NLRP3 inflammasome activation by all Gram-negative bacteria. By engaging TRIF, Gram-negative bacteria activate caspase-11. TRIF activates caspase-11 via type I IFN signaling, an event that is both necessary and sufficient for caspase-11 induction and autoactivation. Caspase-11 subsequently synergizes with the assembled NLRP3 inflammasome to regulate caspase-1 activation and leads to caspase-1-independent cell death. These events occur specifically during infection with Gram-negative, but not Gram-positive, bacteria. The identification of TRIF as a regulator of caspase-11 underscores the importance of TLRs as master regulators of inflammasomes during Gram-negative bacterial infection. PMID:22819539

Urinary tract infections of Escherichia coli strains of chaperone-usher system.

PubMed

Zalewska-Piatek, Beata M

2011-01-01

Urinary tract infections are a very serious health and economic problem affecting millions of people each year worldwide. The most common etiologic agent of this type of bacterial infections, involving the upper and lower urinary tract, are E. coli strains representing approximately 80% of cases. Uropathogenic E. coli strains produce several urovirulence factors which can be divided into two main types, surface virulence factors and exported virulence factors. Surface-exposed structures include mainly extracellular adhesive organelles such as fimbriae/pili necessary in adhesion, invasion, biofilm formation and cytokine induction. Among the surface-exposed polymeric adhesive structures there are three most invasive groups, type 1 pili, type P pili and Dr family of adhesins which are bioassembled via the conserved, among Gram-negative bacteria, chaperone-usher secretion system. Type 1 and P-piliated E. coli cause cystitis and pyelonephritis. The Dr family of adhesins recognizing DAF receptor is responsible for cystitis, pyelonephritis (especially in pregnant women) and diarrhoea (in infants). In addition, Dr-positive E. coli strains carry the risk of recurrent urinary tract infections. Pyelonephritis in pregnant women leads to a series of complications such as bacteremia, urosepsis, acute respiratory distress syndrome and even death. In the era of increasing drug resistance of bacteria, the development of vaccines, drugs termed pilicides and inhibitors of adhesion may be a promising tool in the fight against urogenital infections.

Polymicrobial and microsporidial keratitis in a patient using Boston scleral contact lens for Sjogren's syndrome and ocular cicatricial pemphigoid.

PubMed

Fernandes, Merle; Sharma, Savitri

2013-04-01

To report a rare case of microsporidial and polymicrobial keratitis in a patient with Sjogren's syndrome and ocular cicatricial pemphigoid. This is a descriptive case report. A 66-year-old lady diagnosed with Sjogren's syndrome (SS) and ocular cicatricial pemphigoid (OCP) presented to us with microbial keratitis after using a Boston sclera contact lens for a painful epithelial defect. After 9 days of medical treatment, she underwent therapeutic penetrating keratoplasty. 10% potassium hydroxide and calcofluor white wet mount revealed microsporidial spores. Gram positive cocci and Gram variable bacilli on Gram stain were identified as Staphylococcus epidermidis and Corynebacterium accolens in culture. Histopathological examination of the corneal tissue confirmed the presence of microsporidial spores. Microsporidal keratitis can occur in patients with severe ocular surface disease due to SS and OCP. Predisposing factors include dry eye, local and systemic immunosuppression and Boston scleral contact lens. Early surgical intervention may be needed to eradicate the infection. Copyright © 2012 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Polymicrobial Infective Endocarditis: Clinical Features and Prognosis

PubMed Central

García-Granja, Pablo Elpidio; López, Javier; Vilacosta, Isidre; Ortiz-Bautista, Carlos; Sevilla, Teresa; Olmos, Carmen; Sarriá, Cristina; Ferrera, Carlos; Gómez, Itziar; Román, José Alberto San

2015-01-01

Abstract To describe the profile of left-sided polymicrobial endocarditis (PE) and to compare it with monomicrobial endocarditis (ME). Among 1011 episodes of left-sided endocarditis consecutively diagnosed in 3 tertiary centers, between January 1, 1996 and December 31, 2014, 60 were polymicrobial (5.9%), 821 monomicrobial (81.7%), and in 123 no microorganism was detected (12.2%). Seven patients (0.7%) were excluded from the analysis because contamination of biologic tissue could not be discarded. The authors described the clinical, microbiologic, echocardiographic, and outcome of patients with PE and compared it with ME. Mean age was 64 years SD 16 years, 67% were men and 30% nosocomial. Diabetes mellitus (35%) were the most frequent comorbidities, fever (67%) and heart failure (43%) the most common symptoms at admission. Prosthetic valves (50%) were the most frequent infection location and coagulase-negative Staphylococci (48%) and enterococci (37%) the leading etiologies. The most repeated combination was coagulase-negative Staphylococci with enterococci (n = 9). Polymicrobial endocarditis appeared more frequently in patients with underlying disease (70% versus 56%, P = 0.036), mostly diabetics (35% versus 24%, P = 0.044) with previous cardiac surgery (15% versus 8% P = 0.049) and prosthetic valves (50% versus 37%, P = 0.038). Coagulase-negative Staphylococci, enterococci, Gram-negative bacilli, anaerobes, and fungi were more frequent in PE. No differences on age, sex, symptoms, need of surgery, and in-hospital mortality were detected. Polymicrobial endocarditis represents 5.9% of episodes of left-sided endocarditis in our series. Despite relevant demographic and microbiologic differences between PE and ME, short-term outcome is similar. PMID:26656328

Potential strategies for the eradication of multidrug-resistant Gram-negative bacterial infections.

PubMed

Huwaitat, Rawan; McCloskey, Alice P; Gilmore, Brendan F; Laverty, Garry

2016-07-01

Antimicrobial resistance is one of the leading threats to society. The increasing burden of multidrug-resistant Gram-negative infection is particularly concerning as such bacteria are demonstrating resistance to nearly all currently licensed therapies. Various strategies have been hypothesized to treat multidrug-resistant Gram-negative infections including: targeting the Gram-negative outer membrane; neutralization of lipopolysaccharide; inhibition of bacterial efflux pumps and prevention of protein folding. Silver and silver nanoparticles, fusogenic liposomes and nanotubes are potential strategies for extending the activity of licensed, Gram-positive selective, antibiotics to Gram-negatives. This may serve as a strategy to fill the current void in pharmaceutical development in the short term. This review outlines the most promising strategies that could be implemented to solve the threat of multidrug-resistant Gram-negative infections.

Antimicrobial-resistant Gram-negative bacteria in febrile neutropenic patients with cancer: current epidemiology and clinical impact.

PubMed

Trecarichi, Enrico M; Tumbarello, Mario

2014-04-01

In the recent years, several studies involving cancer patients have demonstrated a clear trend in the epidemiology of bacterial infections showing a shift in the prevalence from Gram-positive to Gram-negative bacteria and the extensive emergence of antimicrobial-resistant strains among Gram-negatives isolated from the blood. The aim of this systematic review was to examine the recent trends in epidemiology and antimicrobial resistance in Gram-negatives recovered from neutropenic cancer patients, with particular emphasis on the impact of antimicrobial resistance on the clinical outcome of severe infections caused by such microorganisms. Overall, from 2007 to date, the rate of Gram-negative bacteria recovery ranged from 24.7 to 75.8% (mean 51.3%) in cancer patient cohorts. Escherichia coli represented the most common species (mean frequency of isolation 32.1%) among the Gram-negatives, followed by Pseudomonas aeruginosa (mean frequency of isolation 20.1%). An increasing frequency of Acinetobacter spp. and Stenotrophomonas maltophilia was also reported. Increased rates of multidrug-resistant Gram-negative strains have been highlighted among Enterobacteriaceae and nonfermenting Gram-negative rods, despite discontinuation of fluoroquinolone-based antibacterial prophylaxis for neutropenic patients. In addition, antimicrobial resistance and/or the inadequacy of empirical antibiotic treatment have been frequently linked to a worse outcome in cancer patients with bloodstream infections caused by Gram-negative isolates. Sound knowledge of the local distribution of pathogens and their susceptibility patterns and prompt initiation of effective antimicrobial treatment for severe infections caused by Gram-negative bacteria are essential in cancer patients.

Accuracy of the cytopathology, bacterioscopy, and vaginal flora culture.

PubMed

Almeida, P Q; Pereira, M A P; Palomo, F S; Okazaki, C; Schimidt, M A; Speck, N M G; Ribalta, J C L

2013-01-01

An over-population of vaginal microorganisms causing inflammatory processes renders it difficult to properly assess the cytopathological exam that aims to screen precedent cervical lesions. On the contrary, the occurrence of the microbial flora saprophyte does not influence correct cythodiagnosis. To assess the composition of vaginal tract aerobic microorganisms of asymptomatic women in menacme and post-menopause, and to analyze the accuracy of cytopathologic, bacterioscopic exams, and culturing of the flora. The women were first submitted to a focused anamnestic interrogatory and then submitted to gynecological exam. A sample of the vaginal fluid was collected with a culture swab and a smear was made on two glass slides for stained bacterioscopic exam (GRAM). The collection of material was then compiled in a cytopathologic smear analysis. All women signed the free and informed consent letter and the project was approved by the Ethics Research Board of Hospital São Paulo - UNIFESP. Bacterioscopy and culture proved to be better than the cytopathologic exam in featuring the bacilli and cocci. The bacterioscopy provided a better detection of the presence of bacilli (p < 0.001); no statistical difference was seen between both exams with respect to the detected cocci. The beta-hemolytic Streptococcus group was of significance in post-menopausal women (p < 0.05). In this study, the bacterioscopic and culture exams of the vaginal fluid were more effective in assessing the vaginal flora and in the detection of bacilli, compared to the cytopathological exam.

Stable Binding of Alternative Protein-enriched Food Matrices with Concentrated Cranberry Bioflavonoids for Functional Food Applications

PubMed Central

Grace, Mary H.; Guzman, Ivette; Roopchand, Diana E.; Moskal, Kristin; Cheng, Diana M.; Pogrebnyak, Natasha; Raskin, Ilya; Howell, Amy; Lila, Mary Ann

2013-01-01

Defatted soy flour (DSF), soy protein isolate (SPI), hemp protein isolate (HPI), medium roast peanut flour (MPF) and pea protein isolate (PPI) stably bind and concentrate cranberry (CB) polyphenols, creating protein/polyphenol-enriched matrices. Proanthocyanidins (PAC) in the enriched matrices ranged from 20.75 mg/g (CB-HPI) to 10.68 mg/g (CB-SPI). Anthocyanins (ANC) ranged from 3.19 mg/g (CB-DSF) to 1.68 mg/g (CB-SPI), while total phenolics (TP) ranged from 37.61 mg/g (CB-HPI) to 21.29 mg/g (CB-SPI). LC-MS indicated that the enriched matrices contained all identifiable ANC, PAC and flavonols present in CB juice. Complexation with SPI stabilized and preserved the integrity of the CB polyphenolic components for at least 15 weeks at 37 °C. PAC isolated from enriched matrices demonstrated comparable anti-adhesion bioactivity to PAC isolated directly from CB juice (MIC 0.4 to 0.16 mg/mL), indicating their potential utility for maintenance of urinary tract health. Approximately 1.0 g of polyphenol-enriched matrix delivered the same amount of PAC available in one cup (300 mL) of commercial CB juice cocktail; which has been shown clinically to be the prophylactic dose for reducing recurring urinary tract infections. CB-SPI inhibited gram- positive and gram-negative bacterial growth. Nutritional and sensory analyses indicated that the targeted CB-matrix combinations have high potential for incorporation in functional food formulations. PMID:23786629

[Pharmacokinetics and clinical efficacy of flomoxef in neonates].

PubMed

Azagami, S; Isohata, E; Takeda, S; Kin, Y; Oikawa, T; Osano, M; Shiro, H

1991-11-01

Clinical pharmacology and efficacy of flomoxef (FMOX) in neonates were investigated. And the following results were obtained. 1. Mean serum concentrations of FMOX at 30 minutes after administration were 24.3 micrograms/ml, 47.6 micrograms/ml, and 85.8 micrograms/ml at doses of 10 mg/kg, 20 mg/kg, and 40 mg/kg administered, respectively. 2. Mean serum half-lives of FMOX were 3.4 hours in 0-3 day-old neonates, and 2.6 hours in 4 day-old or older subjects. 3. A dose response was evident among different dose groups given 10 mg/kg, 20 mg/kg, and 40 mg/kg. 4. Urinary recovery rates of FMOX in the first 6 hours after administration ranged between 12.8 and 51.1%. 5. FMOX was effective in 7 out of 8 cases in which causative pathogens were identified. 6. Diarrhea was observed in 1 case as a side effect of the drug, but the symptom was relieved soon after the completion of the treatment. There was no case in which any abnormal laboratory results were observed. 7. FMOX has a broad spectrum of activities against Gram-positive and Gram-negative aerobes and anaerobes. It is stable against most of beta-lactamases. It was demonstrated to be highly effective in our study, and yet without any serious side effects. FMOX is therefore considered to be one of the useful agents of the first choice for the treatment of bacterial infections such as sepsis and urinary tract infections in neonates and infants.