[Neonatal meningitis caused by atypical Streptococcus pneumoniae: case report and review].

PubMed

Silva B, Verónica; Castillo F, Felipe; O Reilly F, Paula; Araya B, Isabel; Porte T, Lorena; Ulloa F, M Teresa; Varela A, Carmen; Zamorano R, Juanita

2006-12-01

Streptococcus pneumoniae is a rarely recognized cause of neonatal sepsis and/or meningitis, but it is associated with substantial morbidity and mortality. Traditionally, S. pneumoniae is identified in the laboratory by demonstrating susceptibility to optochin. However, the emergence of optochin-resistant organisms makes definite identification difficult when only phenotypic tests are taken as markers. We present the case of a severe early-onset neonatal meningitis due to an atypical strain of S. pneumoniae. Laboratory methods utilized to certify this species diagnosis are discussed.

Lung abscess caused by Streptococcus pneumoniae serotype 6B.

PubMed

Ito, Yuhei; Toyoshima, Hirokazu; Suzuki, Takehiro; Iwamoto, Keisuke; Sasano, Hajime; Itani, Hidetoshi; Kondo, Shigeto; Tanigawa, Motoaki

2018-01-01

Lung abscess has been considered to be a rare complication of pneumococcal infection, and most cases are reported to be Streptococcus pneumoniae serotype 3. A 67-year-old man presented with fever and was diagnosed to have lung abscess caused by S. pneumoniae serotype 6B. The minimal inhibitory concentration (MIC) of penicillin for the isolate was 1 μg/mL. He was treated with high-dose intravenous sulbactam/ampicillin as definitive therapy based on susceptibility testing for S. pneumoniae and recovered successfully without surgical intervention. S. pneumoniae serotype 6B can cause lung abscess.

The Relevance of a Novel Quantitative Assay to Detect up to 40 Major Streptococcus pneumoniae Serotypes Directly in Clinical Nasopharyngeal and Blood Specimens

PubMed Central

Albrich, Werner C.; van der Linden, Mark P. G.; Bénet, Thomas; Chou, Monidarin; Sylla, Mariam; Barreto Costa, Patricia; Richard, Nathalie; Klugman, Keith P.; Endtz, Hubert P.; Paranhos-Baccalà, Gláucia; Telles, Jean-Noël

2016-01-01

For epidemiological and surveillance purposes, it is relevant to monitor the distribution and dynamics of Streptococcus pneumoniae serotypes. Conventional serotyping methods do not provide rapid or quantitative information on serotype loads. Quantitative serotyping may enable prediction of the invasiveness of a specific serotype compared to other serotypes carried. Here, we describe a novel, rapid multiplex real-time PCR assay for identification and quantification of the 40 most prevalent pneumococcal serotypes and the assay impacts in pneumonia specimens from emerging and developing countries. Eleven multiplex PCR to detect 40 serotypes or serogroups were optimized. Quantification was enabled by reference to standard dilutions of known bacterial load. Performance of the assay was evaluated to specifically type and quantify S. pneumoniae in nasopharyngeal and blood samples from adult and pediatric patients hospitalized with pneumonia (n = 664) from five different countries. Serogroup 6 was widely represented in nasopharyngeal specimens from all five cohorts. The most frequent serotypes in the French, South African, and Brazilian cohorts were 1 and 7A/F, 3 and 19F, and 14, respectively. When both samples were available, the serotype in blood was always present as carriage with other serotypes in the nasopharynx. Moreover, the ability of a serotype to invade the bloodstream may be linked to its nasopharyngeal load. The mean nasopharyngeal concentration of the serotypes that moved to the blood was 3 log-fold higher than the ones only found in the nasopharynx. This novel, rapid, quantitative assay may potentially predict some of the S. pneumoniae serotypes invasiveness and assessment of pneumococcal serotype distribution. PMID:26986831

220D-F2 from Rubus ulmifolius kills Streptococcus pneumoniae planktonic cells and pneumococcal biofilms.

PubMed

Talekar, Sharmila J; Chochua, Sopio; Nelson, Katie; Klugman, Keith P; Quave, Cassandra L; Vidal, Jorge E

2014-01-01

Streptococcus pneumoniae (pneumococcus) forms organized biofilms to persist in the human nasopharynx. This persistence allows the pneumococcus to produce severe diseases such as pneumonia, otitis media, bacteremia and meningitis that kill nearly a million children every year. While bacteremia and meningitis are mediated by planktonic pneumococci, biofilm structures are present during pneumonia and otitis media. The global emergence of S. pneumoniae strains resistant to most commonly prescribed antibiotics warrants further discovery of alternative therapeutics. The present study assessed the antimicrobial potential of a plant extract, 220D-F2, rich in ellagic acid, and ellagic acid derivatives, against S. pneumoniae planktonic cells and biofilm structures. Our studies first demonstrate that, when inoculated together with planktonic cultures, 220D-F2 inhibited the formation of pneumococcal biofilms in a dose-dependent manner. As measured by bacterial counts and a LIVE/DEAD bacterial viability assay, 100 and 200 µg/ml of 220D-F2 had significant bactericidal activity against pneumococcal planktonic cultures as early as 3 h post-inoculation. Quantitative MIC's, whether quantified by qPCR or dilution and plating, showed that 80 µg/ml of 220D-F2 completely eradicated overnight cultures of planktonic pneumococci, including antibiotic resistant strains. When preformed pneumococcal biofilms were challenged with 220D-F2, it significantly reduced the population of biofilms 3 h post-inoculation. Minimum biofilm inhibitory concentration (MBIC)50 was obtained incubating biofilms with 100 µg/ml of 220D-F2 for 3 h and 6 h of incubation. 220D-F2 also significantly reduced the population of pneumococcal biofilms formed on human pharyngeal cells. Our results demonstrate potential therapeutic applications of 220D-F2 to both kill planktonic pneumococcal cells and disrupt pneumococcal biofilms.

Plasimids containing the gene for DNA polymerase I from Streptococcus pneumoniae

DOEpatents

Lacks, Sanford A.; Martinez, Susana; Lopez, Paloma; Espinosa, Manuel

1991-01-01

A method is disclosed for cloning the gene which encodes a DNA polymerase-exonuclease of Streptococcus pneumoniae. Plasmid pSM22, the vector containing the pneumocccal polA gene, facilitates the expression of 50-fold greater amounts of the PolI enzyme.

Fatty Acid Metabolism and Ketogenesis in the Rat Exposed to Streptococcus pneumoniae.

DTIC Science & Technology

1980-04-30

livers from rats infected with Streptococctis pneumoniae have a decreased ketogenic capacity compared to fasted controls. This study examines ~jpossible...CLASSIFICATION OF THIS PAGE(Whm De. ime.t pneumococcal sepsis, the decreased ketogenic capacity of the liver is accom- panied by increased hepatic carnitine...accompanies the illness. Previous studies have shown that livers from rats infected with Streptococcus pneumoniae have a decreased ketogenic capacity

Antibacterial effects of Traditional Chinese Medicine monomers against Streptococcus pneumoniae via inhibiting pneumococcal histidine kinase (VicK).

PubMed

Zhang, Shuai; Wang, Jianmin; Xu, Wenchun; Liu, Yusi; Wang, Wei; Wu, Kaifeng; Wang, Zhe; Zhang, Xuemei

2015-01-01

Two-component systems (TCSs) have the potential to be an effective target of the antimicrobials, and thus received much attention in recent years. VicK/VicR is one of TCSs in Streptococcus pneumoniae (S. pneumoniae), which is essential for pneumococcal survival. We have previously obtained several Traditional Chinese Medicine monomers using a computer-based screening. In this study, either alone or in combination with penicillin, their antimicrobial activities were evaluated based on in vivo and in vitro assays. The results showed that the MICs of 5'-(Methylthio)-5'-deoxyadenosine, octanal 2, 4-dinitrophenylhydrazone, deoxyshikonin, kavahin, and dodecyl gallate against S. pneumoniae were 37.1, 38.5, 17, 68.5, and 21 μg/mL, respectively. Time-killing assays showed that these compounds elicited bactericidal effects against S. pneumoniae D39 strain, which led to a 6-log reduction in CFU after exposure to compounds at four times of the MIC for 24 h. The five compounds inhibited the growth of Streptococcus pyogenes, Streptococcus mitis, Streptococcus mutans or Streptococcus pseudopneumoniae, meanwhile, deoxyshikonin and dodecyl gallate displayed strong inhibitory activities against Staphylococcus aureus. These compounds showed no obvious cytotoxicity effects on Vero cells. Survival time of the mice infected by S. pneumoniae strains was prolonged by the treatment with the compounds. Importantly, all of the five compounds exerted antimicrobial effects against multidrug-resistant clinical strains of S. pneumoniae. Moreover, even at sub-MIC concentration, they inhibited cell division and biofilm formation. The five compounds all have enhancement effect on penicillin. Deoxyshikonin and dodecyl gallate showed significantly synergic antimicrobial activity with penicillin in vivo and in vitro, and effectively reduced nasopharyngeal and lung colonization caused by different penicillin-resistant pneumococcal serotypes. In addition, the two compounds also showed synergic antimicrobial activity with erythromycin and tetracycline. Taken together, our results suggest that these novel VicK inhibitors may be promising compounds against the pneumococcus, including penicillin-resistant strains.

Antibodies Reactive to Commensal Streptococcus mitis Show Cross-Reactivity With Virulent Streptococcus pneumoniae Serotypes.

PubMed

Shekhar, Sudhanshu; Khan, Rabia; Ferreira, Daniela M; Mitsi, Elena; German, Esther; Rørvik, Gro Herredsvela; Berild, Dag; Schenck, Karl; Kwon, Keehwan; Petersen, Fernanda

2018-01-01

Current vaccines against Streptococcus pneumoniae , a bacterial species that afflicts people by causing a wide spectrum of diseases, do not protect against all pneumococcal serotypes. Thus, alternative vaccines to fight pneumococcal infections that target common proteins are under investigation. One promising strategy is to take advantage of immune cross-reactivity between commensal and pathogenic microbes for cross-protection. In this study, we examined the antibody-mediated cross-reactivity between S. pneumoniae and Streptococcus mitis , a commensal species closely related to S. pneumoniae . Western blot analysis showed that rabbit antisera raised against S. mitis reacted with multiple proteins of virulent S. pneumoniae strains (6B, TIGR4, and D39). Rabbit anti- S. pneumoniae IgG antibodies also showed binding to S. mitis antigens. Incubation of rabbit antisera raised against S. mitis with heterologous or homologous bacterial lysates resulted in marked inhibition of the developments of bands in the Western blots. Furthermore, plasma IgG antibodies from adult human volunteers intranasally inoculated with S. pneumoniae 6B revealed enhanced S. mitis -specific IgG titers compared with the pre-inoculation samples. Using an on-chip protein microarray representing a number of selected membrane and extracellular S. pneumoniae proteins, we identified choline-binding protein D (CbpD), cell division protein (FtsH), and manganese ABC transporter or manganese-binding adhesion lipoprotein (PsaA) as common targets of the rabbit IgG antibodies raised against S. mitis or S. pneumoniae . Cumulatively, these findings provide evidence on the antibody-mediated cross-reactivity of proteins from S. mitis and S. pneumoniae , which may have implications for development of effective and wide-range pneumococcal vaccines.

Pneumocystis Jiroveci Pneumonia

DTIC Science & Technology

2008-10-01

patients with AIDS include CMV pneumonia, lymphocytic interstitial pneumonia, MAI infection, cryptococcal infection, Legionella , Mycoplasma...negative for Legionella , Streptococcus pneumoniae, and Cryptococcus neoformans. Pneumocystis direct fluorescent antibody (DFA) of the fluid was also

Plasmids containing the gene for DNA polymerase I from Streptococcus pneumoniae

DOEpatents

Lacks, S.A.; Martinez, S.; Lopez, P.; Espinosa, M.

1991-03-26

A method is disclosed for cloning the gene which encodes a DNA polymerase-exonuclease of Streptococcus pneumoniae. Plasmid pSM22, the vector containing the pneumocccal polA gene, facilitates the expression of 50-fold greater amounts of the PolI enzyme. 1 figure.

Acanthamoeba castellanii interactions with Streptococcus pneumoniae and Streptococcus pyogenes.

PubMed

Siddiqui, Ruqaiyyah; Yee Ong, Timothy Yu; Jung, Suk Yul; Khan, Naveed Ahmed

2017-12-01

Among the genus Streptococcus, S. pyogenes and S. pneumoniae are the major causes of pharyngitis, impetigo, pneumonia and meningitis in humans. Streptococcus spp. are facultative anaerobes that are nutritionally fastidious, yet survive in the environment and target the predisposed population. Antibacterial disinfectants have been partially effective only, indicating the need for novel preventative measures and to understand mechanisms of bacterial resistance. Acanthamoeba is a free-living protist that is known to harbour microbial pathogens, provide shelter, and assist in their transmission to susceptible population. The overall aim of this study was to determine whether S. pyogenes and S. pneumoniae can interact with A. castellanii by associating, invading, and surviving inside trophozoites and cysts. It was observed that both S. pyogenes and S. pneumoniae were able to associate as well as invade and/or taken up by the phagocytic A. castellanii trophozoite. Notably, S. pyogenes and S. pneumoniae survived the encystation process, avoided phagocytosis, multiplied, and exhibited higher recovery from the mature cysts, compared with the trophozoite stage (approximately 2 bacteria per amoebae ratio for cyst stage versus 0.02 bacteria per amoeba ration for trophozoite stage). As Acanthamoeba cysts are resilient and can disperse through the air, A. castellanii can act as a vector in providing shelter, facilitating growth and possibly genetic exchanges. In addition, these interactions may contribute to S. pyogenes and S. pneumoniae survival in harsh environments, and transmission to susceptible population and possibly affecting their virulence. Future studies will determine the molecular mechanisms associated with Acanthamoeba interactions with Streptococcus and the evolution of pathogenic bacteria and in turn expedite the discovery of novel therapeutic and/or preventative measures. Copyright © 2017 Elsevier Inc. All rights reserved.

Postantibiotic Effects of ABT-773 and Amoxicillin-Clavulanate against Streptococcus pneumoniae and Haemophilus influenzae

PubMed Central

Neuhauser, Melinda M.; Prause, Jennifer L.; Danziger, Larry H.; Pendland, Susan L.

2001-01-01

This study determined the postantibiotic effect (PAE) of ABT-773 versus that of amoxicillin-clavulanate against clinical isolates of Streptococcus pneumoniae and Haemophilus influenzae. The PAEs of ABT-773 and amoxicillin-clavulanate ranged from 2.3 to 6.0 h and 0 to 2.2 h against S. pneumoniae and from 2.7 to 9.1 h and 0 to 0.8 h against H. influenzae, respectively. PMID:11709352

Plasmids containing the gene for DNA polymerase I from Streptococcus pneumoniae

DOEpatents

Lacks, S.A.; Martinez, S.; Lopez, P.; Espinosa, M.

1987-08-28

A method is disclosed for cloning the gene which encodes a DNA polymerase-exonuclease of /und Streptococcus/ /und pneumoniae/. Plasmid pSM22, the vector containing the pneumococcal polA gene, facilitates the expression of 50-fold greater amounts of the PolI enzyme. 1 fig., 1 tab.

Outbreak of Pneumonia in the Setting of Fatal Pneumococcal Meningitis among US Army Trainees: Potential Role of Chlamydia pneumoniae Infection

DTIC Science & Technology

2011-06-02

Chlamydia pneumoniae, Mycoplasma pneumoniae, Streptococcus pneumoniae, Bordetella pertussis, and Legionella pneumophila[10] in addition to undergoing...and Metzgar D. A multiplex PCR for detection of Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and Bordetella pertussis in

Alterations of Bacteroides sp., Neisseria sp., Actinomyces sp., and Streptococcus sp. populations in the oropharyngeal microbiome are associated with liver cirrhosis and pneumonia.

PubMed

Lu, Haifeng; Qian, Guirong; Ren, Zhigang; Zhang, Chunxia; Zhang, Hua; Xu, Wei; Ye, Ping; Yang, Yunmei; Li, Lanjuan

2015-06-23

The microbiomes of humans are associated with liver and lung inflammation. We identified and verified alterations of the oropharyngeal microbiome and assessed their association with cirrhosis and pneumonia. Study components were as follows: (1) determination of the temporal stability of the oropharyngeal microbiome; (2) identification of oropharyngeal microbial variation in 90 subjects; (3) quantitative identification of disease-associated bacteria. DNAs enriched in bacterial sequences were produced from low-biomass oropharyngeal swabs using whole genome amplification and were analyzed using denaturing gradient gel electrophoresis analysis. Whole genome amplification combined with denaturing gradient gel electrophoresis analysis monitored successfully oropharyngeal microbial variations and showed that the composition of each subject's oropharyngeal microbiome remained relatively stable during the follow-up. The microbial composition of cirrhotic patients with pneumonia differed from those of others and clustered together in subgroup analysis. Further, species richness and the value of Shannon's diversity and evenness index increased significantly in patients with cirrhosis and pneumonia versus others (p < 0.001, versus healthy controls; p < 0.01, versus cirrhotic patients without pneumonia). Moreover, we identified variants of Bacteroides, Eubacterium, Lachnospiraceae, Neisseria, Actinomyces, and Streptococcus through phylogenetic analysis. Quantitative polymerase chain reaction assays revealed that the populations of Bacteroides, Neisseria, and Actinomycetes increased, while that of Streptococcus decreased in cirrhotic patients with pneumonia versus others (p < 0.001, versus Healthy controls; p < 0.01, versus cirrhotic patients without pneumonia). Alterations of Bacteroides, Neisseria, Actinomyces, and Streptococcus populations in the oropharyngeal microbiome were associated with liver cirrhosis and pneumonia.

Evaluation of Several Biochemical and Molecular Techniques for Identification of Streptococcus pneumoniae and Streptococcus pseudopneumoniae and Their Detection in Respiratory Samples

PubMed Central

Schelfaut, Jacqueline J. G.; Bernards, Alexandra T.; Claas, Eric C. J.

2012-01-01

The identification and detection of mitis group streptococci, which contain Streptococcus pneumoniae, have been hampered by the lack of sensitive and specific assays. In this study, we evaluated several biochemical and molecular assays for the identification of S. pneumoniae and Streptococcus pseudopneumoniae and their distinction from other mitis group streptococci using a collection of 54 isolates obtained by the routine culturing of 53 respiratory specimens from patients with community-acquired pneumonia. The combined results of the biochemical and molecular assays indicated the presence of 23 S. pneumoniae, 2 S. pseudopneumoniae, and 29 other mitis group streptococcal isolates. The tube bile solubility test that is considered gold standard for the identification of S. pneumoniae showed concordant results with optochin susceptibility testing (CO2 atmosphere) and a real-time multiplex PCR assay targeting the Spn9802 fragment and the autolysin gene. Optochin susceptibility testing upon incubation in an O2 atmosphere, bile solubility testing by oxgall disk, matrix-assisted laser desorption ionization–time of flight mass spectrometry, and sequence analysis of the tuf and rpoB genes resulted in several false-positive, false-negative, or inconclusive results. The S. pseudopneumoniae isolates could be identified only by molecular assays, and the multiplex real-time PCR assay was concluded to be most convenient for the identification of S. pneumoniae and S. pseudopneumoniae isolates. Using this method, S. pneumoniae and S. pseudopneumoniae DNA could be detected in the respiratory samples from which they were isolated and in an additional 11 samples from which only other streptococci were isolated. PMID:22278834

Design of a multiplex PCR for Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae and Chlamydophila pneumoniae to be used on sputum samples.

PubMed

Strålin, Kristoffer; Bäckman, Anders; Holmberg, Hans; Fredlund, Hans; Olcén, Per

2005-02-01

A multiplex PCR (mPCR) was developed for simultaneous detection of specific genes for Streptococcus pneumoniae (lytA), Mycoplasma pneumoniae (P1), Chlamydophila pneumoniae (ompA), and Haemophilus influenzae (16S rRNA, with verification PCR for P6). When the protocol was tested on 257 bacterial strains belonging to 37 different species, no false negatives and only one false positive were noted. One Streptococcus mitis out of thirty was positive for lytA. In a pilot application study of 81 sputum samples from different patients with suspected lower respiratory tract infection (LRTI), mPCR identified S. pneumoniae in 25 samples, H. influenzae in 29, M. pneumoniae in 3, and C. pneumoniae in 1. All samples culture positive for S. pneumoniae (n=15) and H. influenzae (n=15) were mPCR positive for the same bacteria. In a pilot control study with nasopharyngeal swabs and aspirates from 10 healthy adults, both culture and mPCR were negative. No PCR inhibition was found in any of the mPCR-negative sputum or nasopharyngeal samples. Whether all samples identified as positive by mPCR are truly positive in an aetiological perspective regarding LRTI remains to be evaluated in a well-defined patient material. In conclusion, the mPCR appears to be a promising tool in the aetiological diagnostics of LRTI.

Nasopharyngeal carriage of Streptococcus pneumonia in pneumonia-prone age groups in Semarang, Java Island, Indonesia.

PubMed

Farida, Helmia; Severin, Juliëtte A; Gasem, M Hussein; Keuter, Monique; Wahyono, Hendro; van den Broek, Peterhans; Hermans, Peter W M; Verbrugh, Henri A

2014-01-01

Streptococcus pneumoniae is a worldwide occurring pathogen Nasopharyngeal carriage of Streptococcus pneumoniae precedes pneumonia and other pneumococcal diseases in the community. Little is known about S. pneumoniae carriage in Indonesia, complicating strategies to control pneumococcal diseases. We investigated nasopharyngeal carriage of S. pneumoniae in Semarang, Indonesia. A population-based survey was performed in Semarang, Indonesia. Nasopharyngeal swabs and questionnaires were taken from 496 healthy young (6-60 month-old) children and 45-70 year-old adults. Forty-three percent of children aged 6-60 months and 11% of adults aged 45-75 years carried S. pneumoniae. Determinants of carriage were being a child (OR 7.7; 95% CI = 4.5-13.0), passive smoking (OR 2.1; 95% CI = 1.3-3.4), and contact with toddler(s) at home (OR 3.0; 95% CI = 1.9-4.7). The most frequent serotypes found were 6A/B and 15B/C. The current commercially available vaccines cover <50% serotypes found in children. Twenty-four percent of S. pneumoniae strains were penicillin non-susceptible, and 45% were resistant to cotrimoxazol. The limited coverage of commercially available vaccines against the serotypes found in this population, and the high proportion of non-susceptibility to penicillin and cotrimoxazol suggest the need for region-specific information and strategies to control S. pneumoniae.

Whole-Genome Sequence Analysis of Streptococcus pneumoniae Strains That Cause Hospital-Acquired Pneumonia Infections.

PubMed

Chang, Bin; Morita, Masatomo; Lee, Ken-Ichi; Ohnishi, Makoto

2018-05-01

Streptococcus pneumoniae colonizes the nasopharyngeal mucus in healthy individuals and can cause otitis media, pneumonia, and invasive pneumococcal diseases. In this study, we analyzed S. pneumoniae strains that caused 19 pneumonia episodes in long-term inpatients with severe underlying disease in a hospital during a period of 14 months (from January 2014 to February 2015). Serotyping and whole-genome sequencing analyses revealed that 18 of the 19 pneumonia cases were caused by S. pneumoniae strains belonging to 3 genetically distinct groups: clonal complex 9999 (CC9999), sequence type 282 (ST282), and ST166. The CC9999 and ST282 strains appeared to have emerged separately by a capsule switch from the pandemic PMEN 1 strain (Spain 23F -ST81). After all the long-term inpatients were inoculated with the 23-valent pneumococcal polysaccharide vaccine, no other nosocomial pneumonia infections occurred until March 2016. Copyright © 2018 American Society for Microbiology.

Pneumococcal vaccine (image)

MedlinePlus

Pneumococcal vaccine is an immunization against Streptococcus pneumoniae , a bacterium that frequently causes meningitis and pneumonia in the elderly, and people with chronic illnesses. Pneumococcal pneumonia accounts for 10 ...

The alpha-tocopherol form of vitamin E reverses age-associated susceptibility to Streptococcus pneumoniae lung infection by modulating pulmonary neutrophil recruitment

USDA-ARS?s Scientific Manuscript database

Streptococcus pneumonia infections are an important cause of morbidity and mortality in older patients. Uncontrolled neutrophil-driven pulmonary inflammation exacerbates this disease. To test whether the alpha-tocopherol (alpha-Toc) form of vitamin E, a regulator of immunity, can modulate neutrophil...

Evolution of Streptococcus pneumoniae and Its Close Commensal Relatives

PubMed Central

Kilian, Mogens; Poulsen, Knud; Blomqvist, Trinelise; Håvarstein, Leiv S.; Bek-Thomsen, Malene; Tettelin, Hervé; Sørensen, Uffe B. S.

2008-01-01

Streptococcus pneumoniae is a member of the Mitis group of streptococci which, according to 16S rRNA-sequence based phylogenetic reconstruction, includes 12 species. While other species of this group are considered prototypes of commensal bacteria, S. pneumoniae is among the most frequent microbial killers worldwide. Population genetic analysis of 118 strains, supported by demonstration of a distinct cell wall carbohydrate structure and competence pheromone sequence signature, shows that S. pneumoniae is one of several hundred evolutionary lineages forming a cluster separate from Streptococcus oralis and Streptococcus infantis. The remaining lineages of this distinct cluster are commensals previously collectively referred to as Streptococcus mitis and each represent separate species by traditional taxonomic standard. Virulence genes including the operon for capsule polysaccharide synthesis and genes encoding IgA1 protease, pneumolysin, and autolysin were randomly distributed among S. mitis lineages. Estimates of the evolutionary age of the lineages, the identical location of remnants of virulence genes in the genomes of commensal strains, the pattern of genome reductions, and the proportion of unique genes and their origin support the model that the entire cluster of S. pneumoniae, S. pseudopneumoniae, and S. mitis lineages evolved from pneumococcus-like bacteria presumably pathogenic to the common immediate ancestor of hominoids. During their adaptation to a commensal life style, most of the lineages gradually lost the majority of genes determining virulence and became genetically distinct due to sexual isolation in their respective hosts. PMID:18628950

Identification of proteins in Streptococcus pneumoniae by reverse vaccinology and genetic diversity of these proteins in clinical isolates.

PubMed

Argondizzo, Ana Paula Corrêa; da Mota, Fabio Faria; Pestana, Cristiane Pinheiro; Reis, Joice Neves; de Miranda, Antonio Basílio; Galler, Ricardo; Medeiros, Marco Alberto

2015-02-01

Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. Virulence-associated proteins common and conserved among all capsular types now represent the best strategy to combat pneumococcal infections. Our aim was to identify conserved targets in pneumococci that showed positive prediction for lipoprotein and extracellular subcellular location using bioinformatics programs and verify the distribution and the degree of conservation of these targets in pneumococci. These targets can be considered potential vaccine candidate to be evaluated in the future. A set of 13 targets were analyzed and confirmed the presence in all pneumococci tested. These 13 genes were highly conserved showing around >96 % of amino acid and nucleotide identity, but they were also present and show high identity in the closely related species Streptococcus mitis, Streptococcus oralis, and Streptococcus pseudopneumoniae. S. oralis clusters away from S. pneumoniae, while S. pseudopneumoniae and S. mitis cluster closer. The divergence between the selected targets was too small to be observed consistently in phylogenetic groups between the analyzed genomes of S. pneumoniae. The proteins analyzed fulfill two of the initial criteria of a vaccine candidate: targets are present in a variety of different pneumococci strains including different serotypes and are conserved among the samples evaluated.

Predicting pneumococcal community-acquired pneumonia in the emergency department: evaluation of clinical parameters.

PubMed

Huijts, S M; Boersma, W G; Grobbee, D E; Gruber, W C; Jansen, K U; Kluytmans, J A J W; Kuipers, B A F; Palmen, F; Pride, M W; Webber, C; Bonten, M J M

2014-12-01

The aim of this study was to quantify the value of clinical predictors available in the emergency department (ED) in predicting Streptococcus pneumoniae as the cause of community-acquired pneumonia (CAP). A prospective, observational, cohort study of patients with CAP presenting in the ED was performed. Pneumococcal aetiology of CAP was based on either bacteraemia, or S. pneumoniae being cultured from sputum, or urinary immunochromatographic assay positivity, or positivity of a novel serotype-specific urinary antigen detection test. Multivariate logistic regression was used to identify independent predictors and various cut-off values of probability scores were used to evaluate the usefulness of the model. Three hundred and twenty-eight (31.0%) of 1057 patients with CAP had pneumococcal CAP. Nine independent predictors for pneumococcal pneumonia were identified, but the clinical utility of this prediction model was disappointing, because of low positive predictive values or a small yield. Clinical criteria have insufficient diagnostic capacity to predict pneumococcal CAP. Rapid antigen detection tests are needed to diagnose S. pneumoniae at the time of hospital admission. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

Parallel evolution of Streptococcus pneumoniae and Streptococcus mitis to pathogenic and mutualistic lifestyles.

PubMed

Kilian, Mogens; Riley, David R; Jensen, Anders; Brüggemann, Holger; Tettelin, Hervé

2014-07-22

The bacterium Streptococcus pneumoniae is one of the leading causes of fatal infections affecting humans. Intriguingly, phylogenetic analysis shows that the species constitutes one evolutionary lineage in a cluster of the otherwise commensal Streptococcus mitis strains, with which humans live in harmony. In a comparative analysis of 35 genomes, including phylogenetic analyses of all predicted genes, we have shown that the pathogenic pneumococcus has evolved into a master of genomic flexibility while lineages that evolved into the nonpathogenic S. mitis secured harmonious coexistence with their host by stabilizing an approximately 15%-reduced genome devoid of many virulence genes. Our data further provide evidence that interspecies gene transfer between S. pneumoniae and S. mitis occurs in a unidirectional manner, i.e., from S. mitis to S. pneumoniae. Import of genes from S. mitis and other mitis, anginosus, and salivarius group streptococci ensured allelic replacements and antigenic diversification and has been driving the evolution of the remarkable structural diversity of capsular polysaccharides of S. pneumoniae. Our study explains how the unique structural diversity of the pneumococcal capsule emerged and conceivably will continue to increase and reveals a striking example of the fragile border between the commensal and pathogenic lifestyles. While genomic plasticity enabling quick adaptation to environmental stress is a necessity for the pathogenic streptococci, the commensal lifestyle benefits from stability. Importance: One of the leading causes of fatal infections affecting humans, Streptococcus pneumoniae, and the commensal Streptococcus mitis are closely related obligate symbionts associated with hominids. Faced with a shortage of accessible hosts, the two opposing lifestyles evolved in parallel. We have shown that the nonpathogenic S. mitis secured harmonious coexistence with its host by stabilizing a reduced genome devoid of many virulence genes. Meanwhile, the pathogenic pneumococcus evolved into a master of genomic flexibility and imports genes from S. mitis and other related streptococci. This process ensured antigenic diversification and has been driving the evolution of the remarkable structural diversity of capsular polysaccharides of S. pneumoniae, which conceivably will continue to increase and present a challenge to disease prevention. Copyright © 2014 Kilian et al.

Genetic Relationships between Clinical Isolates of Streptococcus pneumoniae, Streptococcus oralis, and Streptococcus mitis: Characterization of “Atypical” Pneumococci and Organisms Allied to S. mitis Harboring S. pneumoniae Virulence Factor-Encoding Genes

PubMed Central

Whatmore, Adrian M.; Efstratiou, Androulla; Pickerill, A. Paul; Broughton, Karen; Woodard, Geoffrey; Sturgeon, Daniel; George, Robert; Dowson, Christopher G.

2000-01-01

The oral streptococcal group (mitis phylogenetic group) currently consists of nine recognized species, although the group has been traditionally difficult to classify, with frequent changes in nomenclature over the years. The pneumococcus (Streptococcus pneumoniae), an important human pathogen, is traditionally distinguished from the most closely related oral streptococcal species Streptococcus mitis and Streptococcus oralis on the basis of three differentiating characteristics: optochin susceptibility, bile solubility, and agglutination with antipneumococcal polysaccharide capsule antibodies. However, there are many reports in the literature of pneumococci lacking one or more of these defining characteristics. Sometimes called “atypical” pneumococci, these isolates can be the source of considerable confusion in the clinical laboratory. Little is known to date about the genetic relationships of such organisms with classical S. pneumoniae isolates. Here we describe these relationships based on sequence analysis of housekeeping genes in comparison with previously characterized isolates of S. pneumoniae, S. mitis, and S. oralis. While most pneumococci were found to represent a closely related group these studies identified a subgroup of atypical pneumococcal isolates (bile insoluble and/or “acapsular”) distinct from, though most closely related to, the “typical” pneumococcal isolates. However, a large proportion of isolates, found to be atypical on the basis of capsule reaction alone, did group with typical pneumococci, suggesting that they have either lost capsule production or represent as-yet-unrecognized capsular types. In contrast to typical S. pneumoniae, isolates phenotypically identified as S. mitis and S. oralis, which included isolates previously characterized in taxonomic studies, were genetically diverse. While most of the S. oralis isolates did fall into a well-separated group, S. mitis isolates did not cluster into a well-separated group. During the course of these studies we also identified a number of potentially important pathogenic isolates, which were frequently associated with respiratory disease, that phenotypically and genetically are most closely related to S. mitis but which harbor genes encoding the virulence determinants pneumolysin and autolysin classically associated with S. pneumoniae. PMID:10678950

Strain Level Streptococcus Colonization Patterns during the First Year of Life

PubMed Central

Wright, Meredith S.; McCorrison, Jamison; Gomez, Andres M.; Beck, Erin; Harkins, Derek; Shankar, Jyoti; Mounaud, Stephanie; Segubre-Mercado, Edelwisa; Mojica, Aileen May R.; Bacay, Brian; Nzenze, Susan A.; Kimaro, Sheila Z. M.; Adrian, Peter; Klugman, Keith P.; Lucero, Marilla G.; Nelson, Karen E.; Madhi, Shabir; Sutton, Granger G.; Nierman, William C.; Losada, Liliana

2017-01-01

Pneumococcal pneumonia has decreased significantly since the implementation of the pneumococcal conjugate vaccine (PCV), nevertheless, in many developing countries pneumonia mortality in infants remains high. We have undertaken a study of the nasopharyngeal (NP) microbiome during the first year of life in infants from The Philippines and South Africa. The study entailed the determination of the Streptococcus sp. carriage using a lytA qPCR assay, whole metagenomic sequencing, and in silico serotyping of Streptococcus pneumoniae, as well as 16S rRNA amplicon based community profiling. The lytA carriage in both populations increased with infant age and lytA+ samples ranged from 24 to 85% of the samples at each sampling time point. We next developed informatic tools for determining Streptococcus community composition and pneumococcal serotype from metagenomic sequences derived from a subset of longitudinal lytA-positive Streptococcus enrichment cultures from The Philippines (n = 26 infants, 50% vaccinated) and South African (n = 7 infants, 100% vaccinated). NP samples from infants were passaged in enrichment media, and metagenomic DNA was purified and sequenced. In silico capsular serotyping of these 51 metagenomic assemblies assigned known serotypes in 28 samples, and the co-occurrence of serotypes in 5 samples. Eighteen samples were not typeable using known serotypes but did encode for capsule biosynthetic cluster genes similar to non-encapsulated reference sequences. In addition, we performed metagenomic assembly and 16S rRNA amplicon profiling to understand co-colonization dynamics of Streptococcus sp. and other NP genera, revealing the presence of multiple Streptococcus species as well as potential respiratory pathogens in healthy infants. A range of virulence and drug resistant elements were identified as circulating in the NP microbiomes of these infants. This study revealed the frequent co-occurrence of multiple S. pneumoniae strains along with Streptococcus sp. and other potential pathogens such as S. aureus in the NP microbiome of these infants. In addition, the in silico serotype analysis proved powerful in determining the serotypes in S. pneumoniae carriage, and may lead to developing better targeted vaccines to prevent invasive pneumococcal disease (IPD) in these countries. These findings suggest that NP colonization by S. pneumoniae during the first years of life is a dynamic process involving multiple serotypes and species. PMID:28932211

Molecular biology of Streptococcus pneumoniae: an everlasting challenge.

PubMed

Sicard, M; Gasc, A M; Giammarinaro, P; Lefrançois, J; Pasta, F; Samrakandi, M

2000-01-01

Streptococcus pneumoniae is a model for elucidating: 1) recombination steps of DNA, from its discovery to polarity of integration; 2) long-patch mismatch repair, short-patch repair triggered by A/G and exclusion of deletions; 3) resistance to beta-lactam antibiotics; and 4) factors of virulence. Several of these topics remain a challenge for future investigations.

Nasopharyngeal Carriage of Streptococcus pneumonia in Pneumonia-Prone Age Groups in Semarang, Java Island, Indonesia

PubMed Central

Farida, Helmia; Severin, Juliëtte A.; Gasem, M. Hussein; Keuter, Monique; Wahyono, Hendro; van den Broek, Peterhans; Hermans, Peter W. M.; Verbrugh, Henri A.

2014-01-01

Introduction Streptococcus pneumoniae is a worldwide occurring pathogen Nasopharyngeal carriage of Streptococcus pneumoniae precedes pneumonia and other pneumococcal diseases in the community. Little is known about S. pneumoniae carriage in Indonesia, complicating strategies to control pneumococcal diseases. We investigated nasopharyngeal carriage of S. pneumoniae in Semarang, Indonesia. Methods A population-based survey was performed in Semarang, Indonesia. Nasopharyngeal swabs and questionnaires were taken from 496 healthy young (6–60 month-old) children and 45–70 year-old adults. Results Forty-three percent of children aged 6–60 months and 11% of adults aged 45–75 years carried S. pneumoniae. Determinants of carriage were being a child (OR 7.7; 95% CI = 4.5–13.0), passive smoking (OR 2.1; 95% CI = 1.3–3.4), and contact with toddler(s) at home (OR 3.0; 95% CI = 1.9–4.7). The most frequent serotypes found were 6A/B and 15B/C. The current commercially available vaccines cover <50% serotypes found in children. Twenty-four percent of S. pneumoniae strains were penicillin non-susceptible, and 45% were resistant to cotrimoxazol. Conclusions The limited coverage of commercially available vaccines against the serotypes found in this population, and the high proportion of non-susceptibility to penicillin and cotrimoxazol suggest the need for region-specific information and strategies to control S. pneumoniae. PMID:24498104

A novel flow cytometry-based assay for the quantification of antibody-dependent pneumococcal agglutination

PubMed Central

van der Gaast—de Jongh, Christa E.; Diavatopoulos, Dimitri A.; de Jonge, Marien I.

2017-01-01

The respiratory pathogen Streptococcus pneumoniae is a major cause of diseases such as otitis media, pneumonia, sepsis and meningitis. The first step towards infection is colonization of the nasopharynx. Recently, it was shown that agglutinating antibodies play an important role in the prevention of mucosal colonization with S. pneumoniae. Here, we present a novel method to quantify antibody-dependent pneumococcal agglutination in a high-throughput manner using flow cytometry. We found that the concentration of agglutinating antibodies against pneumococcal capsule are directly correlated with changes in the size and complexity of bacterial aggregates, as measured by flow cytometry and confirmed by light microscopy. Using the increase in size, we determined the agglutination index. The cutoff value was set by measuring a series of non-agglutinating antibodies. With this method, we show that not only anti-polysaccharide capsule antibodies are able to induce agglutination but that also anti-PspA protein antibodies have agglutinating capabilities. In conclusion, we have described and validated a novel method to quantify pneumococcal agglutination, which can be used to screen sera from murine or human vaccination studies, in a high-throughput manner. PMID:28288168

Impact of Antimicrobial Treatment for Acute Otitis Media on Carriage Dynamics of Penicillin-susceptible and Penicillin-non-susceptible Streptococcus pneumoniae.

PubMed

Lewnard, Joseph A; Tähtinen, Paula A; Laine, Miia K; Lindholm, Laura; Jalava, Jari; Huovinen, Pentti; Lipsitch, Marc; Ruohola, Aino

2018-06-05

Despite concerns that antimicrobial treatment of prevalent infections may select for drug-resistant bacteria, the effects of antimicrobial treatment on colonization dynamics have not been well quantified. We measured impacts of antimicrobial treatment on nasopharyngeal carriage of penicillin-susceptible Streptococcus pneumoniae (PSSP) and penicillin-non-susceptible (PNSP) lineages at end-of-treatment and 15d, 30d, and 60d after treatment in a previously-conducted randomized, double-blind, placebo-controlled trial of amoxicillin-clavulanate for stringently-defined acute otitis media. In intention-to-treat analyses, immediate amoxicillin-clavulanate reduced PSSP carriage prevalence by 88% (95%CI: 76-96%) at end-of-treatment and by 27% (-3-49%) after 60d, but did not alter PNSP carriage prevalence. By end-of-treatment, 7% of children who carried PSSP at enrollment remained colonized in the amoxicillin-clavulanate arm, versus 61% of PSSP carriers who received placebo; impacts of amoxicillin-clavulanate persisted at least 60d after treatment among children who carried PSSP at enrollment. Amoxicillin-clavulanate reduced PSSP acquisition by >80% over 15d. Among children who carried PNSP at enrollment, no impacts on carriage prevalence of S. pneumoniae, PSSP, or PNSP were evident at follow-up visits. Although absolute risk of carrying PNSP was unaffected by treatment, antimicrobial therapy conferred a selective impact on colonizing pneumococci by accelerating clearance, and delaying acquisition, of PSSP.

Prevalence and antibiotic resistance profiles of cerebrospinal fluid pathogens in children with acute bacterial meningitis in Yunnan province, China, 2012-2015

PubMed Central

Jiang, Hongchao; Su, Min; Kui, Liyue; Huang, Hailin; Qiu, Lijuan; Li, Li; Ma, Jing; Du, Tingyi; Fan, Mao; Liu, Xiaomei

2017-01-01

Acute bacterial meningitis is still considered one of the most dangerous infectious diseases in children. To investigate the prevalence and antibiotic resistance profiles of cerebrospinal fluid (CSF) pathogens in children with acute bacterial meningitis in Southwest China, CSF samples from 179 meningitis patients (3 days to 12 years old) with positive culture results were collected from 2012 to 2015. Isolated pathogens were identified using the Vitek-32 system. Gram stain results were used to guide subcultures and susceptibility testing. The antimicrobial susceptibility of isolates was determined using the disc diffusion method. Of the isolates, 50.8% were Gram-positive bacteria, and 49.2% were Gram-negative bacteria. The most prevalent pathogens were E. coli (28.5%), Streptococcus pneumoniae (17.8%), Staphylococcus epidermidis (10.0%), Haemophilus influenzae type b (9.5%), and group B streptococcus (7.2%). In young infants aged ≤3 months, E. coli was the organism most frequently isolated from CSF (39/76; 51.3%), followed by group B streptococcus (13/76; 17.1%) and Streptococcus pneumoniae (8/76; 10.5%). However, in young infants aged >3 months, the most frequently isolated organism was Streptococcus pneumoniae (24/103; 23.3%), followed by Staphylococcus epidermidis (18/103; 17.5%) and Haemophilus influenzae type b (16/103; 15.5%). Antimicrobial susceptibility tests indicated that for E. coli isolates, the susceptibility rates to aminoglycosides ranged from 56.8% to 100.0%, among them, amikacin was identified as the most effective against E. coli. As for cephalosporins, the susceptibility rates ranged from 29.4% to 78.4%, and cefoxitin was identified as the most effective cephalosporin. In addition, the susceptibility rates of piperacillin/tazobactam and imipenem against E. coli were 86.3% and 100%. Meanwhile, the susceptibility rates of Streptococcus pneumoniae isolates to penicillin G, erythromycin, chloramphenicol, ceftriaxone and tetracycline were 68.8%, 0.0%, 87.5%, 81.3% and 0.0%, respectively. Gentamycin, ofloxacin, linezolid and vancomycin were identified as the most effective antibiotics for Streptococcus pneumoniae, each with susceptibility rates of 100%. It was notable that other emerging pathogens, such as Listeria monocytogenes and group D streptococcus, cannot be underestimated in meningitis. PMID:28662145

Prevalence and antibiotic resistance profiles of cerebrospinal fluid pathogens in children with acute bacterial meningitis in Yunnan province, China, 2012-2015.

PubMed

Jiang, Hongchao; Su, Min; Kui, Liyue; Huang, Hailin; Qiu, Lijuan; Li, Li; Ma, Jing; Du, Tingyi; Fan, Mao; Sun, Qiangming; Liu, Xiaomei

2017-01-01

Acute bacterial meningitis is still considered one of the most dangerous infectious diseases in children. To investigate the prevalence and antibiotic resistance profiles of cerebrospinal fluid (CSF) pathogens in children with acute bacterial meningitis in Southwest China, CSF samples from 179 meningitis patients (3 days to 12 years old) with positive culture results were collected from 2012 to 2015. Isolated pathogens were identified using the Vitek-32 system. Gram stain results were used to guide subcultures and susceptibility testing. The antimicrobial susceptibility of isolates was determined using the disc diffusion method. Of the isolates, 50.8% were Gram-positive bacteria, and 49.2% were Gram-negative bacteria. The most prevalent pathogens were E. coli (28.5%), Streptococcus pneumoniae (17.8%), Staphylococcus epidermidis (10.0%), Haemophilus influenzae type b (9.5%), and group B streptococcus (7.2%). In young infants aged ≤3 months, E. coli was the organism most frequently isolated from CSF (39/76; 51.3%), followed by group B streptococcus (13/76; 17.1%) and Streptococcus pneumoniae (8/76; 10.5%). However, in young infants aged >3 months, the most frequently isolated organism was Streptococcus pneumoniae (24/103; 23.3%), followed by Staphylococcus epidermidis (18/103; 17.5%) and Haemophilus influenzae type b (16/103; 15.5%). Antimicrobial susceptibility tests indicated that for E. coli isolates, the susceptibility rates to aminoglycosides ranged from 56.8% to 100.0%, among them, amikacin was identified as the most effective against E. coli. As for cephalosporins, the susceptibility rates ranged from 29.4% to 78.4%, and cefoxitin was identified as the most effective cephalosporin. In addition, the susceptibility rates of piperacillin/tazobactam and imipenem against E. coli were 86.3% and 100%. Meanwhile, the susceptibility rates of Streptococcus pneumoniae isolates to penicillin G, erythromycin, chloramphenicol, ceftriaxone and tetracycline were 68.8%, 0.0%, 87.5%, 81.3% and 0.0%, respectively. Gentamycin, ofloxacin, linezolid and vancomycin were identified as the most effective antibiotics for Streptococcus pneumoniae, each with susceptibility rates of 100%. It was notable that other emerging pathogens, such as Listeria monocytogenes and group D streptococcus, cannot be underestimated in meningitis.

Quorum Sensing Regulation of Competence and Bacteriocins in Streptococcus pneumoniae and mutans

PubMed Central

Shanker, Erin; Federle, Michael J.

2017-01-01

The human pathogens Streptococcus pneumoniae and Streptococcus mutans have both evolved complex quorum sensing (QS) systems that regulate the production of bacteriocins and the entry into the competent state, a requirement for natural transformation. Natural transformation provides bacteria with a mechanism to repair damaged genes or as a source of new advantageous traits. In S. pneumoniae, the competence pathway is controlled by the two-component signal transduction pathway ComCDE, which directly regulates SigX, the alternative sigma factor required for the initiation into competence. Over the past two decades, effectors of cellular killing (i.e., fratricides) have been recognized as important targets of the pneumococcal competence QS pathway. Recently, direct interactions between the ComCDE and the paralogous BlpRH pathway, regulating bacteriocin production, were identified, further strengthening the interconnections between these two QS systems. Interestingly, a similar theme is being revealed in S. mutans, the primary etiological agent of dental caries. This review compares the relationship between the bacteriocin and the competence QS pathways in both S. pneumoniae and S. mutans, and hopes to provide clues to regulatory pathways across the genus Streptococcus as a potential tool to efficiently investigate putative competence pathways in nontransformable streptococci. PMID:28067778

Effect of Pneumococcal Vaccination on Nasopharyngeal Carriage of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus in Fijian Children

PubMed Central

Manning, Jayne; Russell, Fiona M.; Robins-Browne, Roy M.; Mulholland, E. Kim; Satzke, Catherine

2012-01-01

The 7-valent pneumococcal conjugate vaccine (PCV7) reduces carriage of vaccine type Streptococcus pneumoniae but leads to replacement by nonvaccine serotypes and may affect carriage of other respiratory pathogens. We investigated nasopharyngeal carriage of S. pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus in Fijian infants participating in a pneumococcal vaccine trial using quantitative PCR. Vaccination did not affect pathogen carriage rates or densities, whereas significant differences between the two major ethnic groups were observed. PMID:22170924

Streptococcus pneumoniae secretes hydrogen peroxide leading to DNA damage and apoptosis in lung cells.

PubMed

Rai, Prashant; Parrish, Marcus; Tay, Ian Jun Jie; Li, Na; Ackerman, Shelley; He, Fang; Kwang, Jimmy; Chow, Vincent T; Engelward, Bevin P

2015-06-30

Streptococcus pneumoniae is a leading cause of pneumonia and one of the most common causes of death globally. The impact of S. pneumoniae on host molecular processes that lead to detrimental pulmonary consequences is not fully understood. Here, we show that S. pneumoniae induces toxic DNA double-strand breaks (DSBs) in human alveolar epithelial cells, as indicated by ataxia telangiectasia mutated kinase (ATM)-dependent phosphorylation of histone H2AX and colocalization with p53-binding protein (53BP1). Furthermore, results show that DNA damage occurs in a bacterial contact-independent fashion and that Streptococcus pyruvate oxidase (SpxB), which enables synthesis of H2O2, plays a critical role in inducing DSBs. The extent of DNA damage correlates with the extent of apoptosis, and DNA damage precedes apoptosis, which is consistent with the time required for execution of apoptosis. Furthermore, addition of catalase, which neutralizes H2O2, greatly suppresses S. pneumoniae-induced DNA damage and apoptosis. Importantly, S. pneumoniae induces DSBs in the lungs of animals with acute pneumonia, and H2O2 production by S. pneumoniae in vivo contributes to its genotoxicity and virulence. One of the major DSBs repair pathways is nonhomologous end joining for which Ku70/80 is essential for repair. We find that deficiency of Ku80 causes an increase in the levels of DSBs and apoptosis, underscoring the importance of DNA repair in preventing S. pneumoniae-induced genotoxicity. Taken together, this study shows that S. pneumoniae-induced damage to the host cell genome exacerbates its toxicity and pathogenesis, making DNA repair a potentially important susceptibility factor in people who suffer from pneumonia.

[Microbiology of bronchoalveolar lavage in infants with bacterial community-acquired pneumonia with poor outcome].

PubMed

García-Elorriaga, Guadalupe; Palma-Alaniz, Laura; García-Bolaños, Carlos; Ruelas-Vargas, Consuelo; Méndez-Tovar, Socorro; Del Rey-Pineda, Guillermo

Community-acquired pneumonia (CAP) is one of the most common infectious causes of morbidity and mortality in children <5 years of age. The aim of the study was to clarify the bacterial etiologic diagnosis in infants with CAP. A prospective, cross-sectional and descriptive study in patients 6 months to 2 years 11 months of age with CAP with poor outcome was conducted. Patients were admitted to the Pediatric Pneumology Service and underwent bronchoscopy with bronchoalveolar lavage (BAL), taking appropriate measures during the procedure to limit the risk of contamination. Aerobic bacteria isolated were Moraxella sp. 23%, Streptococcus mitis 23%, Streptococcus pneumoniae 18%, Haemophilus influenzae 12%, Streptococcus oralis 12%, and Streptococcus salivarius 12%. In contrast to other reports, we found Moraxella sp. to be a major bacterial pathogen, possibly because of improved detection with bronchoscopy plus BAL. Copyright © 2015 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Immunochemical cross-reactions between type III group B Streptococcus and type 14 Streptococcus pneumoniae.

PubMed Central

Crumrine, M H; Fischer, G W; Balk, M W

1979-01-01

Serological cross-reactions between certain streptococci and some serotypes of Streptococcus pneumoniae have been reported. These studies detail the serological cross-reactivity observed between hot HCl-extracted group b streptococcus type III (GBS III) antigens and S. pneumoniae type 14 (Pn 14) polysaccharide. Similar electrophoretic migration patterns of GBS III and Pn 14 were observed when either type-specific BGS III antisera or pneumococcal omniserum was utilized to precipitate these antigens. Both the GBS III antigen and the Pn 14 polysaccharide migrated toward the cathode, whereas all other pneumococcal polysaccharides migrated toward the anode. No cross-reactions were observed between GBS III antisera and the 11 other types of pneumococcal polysaccharides. Lines of identity were observed between type-specific GBS III antisera and monospecific Pn 14 antiserum with either GBS III antigens or purified Pn 14 polysaccharide. The cross-reacting antigens of GBS III and Pn 14 appear to be identical by immunodiffusion and immunoelectrophoresis. Images PMID:40876

Screening of binding activity of Streptococcus pneumoniae, Streptococcus agalactiae and Streptococcus suis to berries and juices.

PubMed

Toivanen, Marko; Huttunen, Sanna; Duricová, Jana; Soininen, Pasi; Laatikainen, Reino; Loimaranta, Vuokko; Haataja, Sauli; Finne, Jukka; Lapinjoki, Seppo; Tikkanen-Kaukanen, Carina

2010-01-01

Antiadhesion therapy is a promising approach to the fight against pathogens. Antibiotic resistance and the lack of effective vaccines have increased the search for new methods to prevent infectious diseases. Previous studies have shown the antiadhesion activity of juice from cultivated cranberries (Vaccinium macrocarpon Ait.) against bacteria, especially E. coli. In this study, the binding of two streptococcal strains, Streptococcus pneumoniae and Streptococcus agalactiae, to molecular size fractions (FI, FII and FIII, <10 kDa, 10-100 kDa, and >100 kDa, respectively) of berries and berry and fruit juices from 12 plant species were studied using a microtiter well assay. For Streptococcus suis a hemagglutination inhibition assay was used. In general, binding activity was detected especially to wild cranberry (Vaccinium oxycoccos L.) and to other Vaccinium species. S. pneumoniae cells bound most to cranberry juice fraction FI and S. agalactiae cells to cranberry fraction FIII. Hemagglutination induced by S. suis was most effectively inhibited by cranberry fraction FII. NMR spectra of some characteristic active and non-active fractions were also measured. They indicate that fractions FII and FIII contained proanthocyanidins and/or other phenolic compounds. The results suggest Vaccinium berries as possible sources of antiadhesives against bacterial infections.

Immune cell activation and cytokine release after stimulation of whole blood with pneumococcal C-polysaccharide and capsular polysaccharides.

PubMed

Sundberg-Kövamees, Marianne; Grunewald, Johan; Wahlström, Jan

2016-11-01

Streptococcus pneumonia is a major cause of morbidity and mortality in children and adults worldwide. Lack of fully effective pneumococcal vaccines is a problem. Streptococcus pneumoniae exposes on its surface C-polysaccharide (cell wall polysaccharide, CWPS) and serospecific capsular polysaccharides, used in pneumococcal vaccines. We investigated the effect of CWPS and individual capsular polysaccharides, with regard to activation of subsets of immune cells of healthy controls. Three different capsular polysaccharides, CWPS and LPS were used for in vitro stimulation of whole blood. Cell activation (CD69 expression) was assessed in CD4+ and CD4- T cells, NK-like T cells, NK cells and monocytes by flow cytometry. Cytokine levels in supernatants were quantified by Cytometric Bead Array (CBA). CWPS and the capsules activated immune cell subsets, but to different degrees. NK cells and NK-like T cells showed the strongest activation, followed by monocytes. Among the three capsules, capsule type 23 induced the strongest activation and cytokine release, followed by type 9 and type 3. This study increases the understanding of how the human immune system reacts to pneumococcal vaccine components. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Streptococcus pneumoniae Supragenome Hybridization Arrays for Profiling of Genetic Content and Gene Expression.

PubMed

Kadam, Anagha; Janto, Benjamin; Eutsey, Rory; Earl, Joshua P; Powell, Evan; Dahlgren, Margaret E; Hu, Fen Z; Ehrlich, Garth D; Hiller, N Luisa

2015-02-02

There is extensive genomic diversity among Streptococcus pneumoniae isolates. Approximately half of the comprehensive set of genes in the species (the supragenome or pangenome) is present in all the isolates (core set), and the remaining is unevenly distributed among strains (distributed set). The Streptococcus pneumoniae Supragenome Hybridization (SpSGH) array provides coverage for an extensive set of genes and polymorphisms encountered within this species, capturing this genomic diversity. Further, the capture is quantitative. In this manner, the SpSGH array allows for both genomic and transcriptomic analyses of diverse S. pneumoniae isolates on a single platform. In this unit, we present the SpSGH array, and describe in detail its design and implementation for both genomic and transcriptomic analyses. The methodology can be applied to construction and modification of SpSGH array platforms, as well to other bacterial species as long as multiple whole-genome sequences are available that collectively capture the vast majority of the species supragenome. Copyright © 2015 John Wiley & Sons, Inc.

Prevalence of Streptococcus pneumoniae serotype 6C among invasive and carriage isolates in metropolitan Salvador, Brazil from 1996-2007

PubMed Central

Campos, Leila C.; Carvalho, Maria da Gloria S.; Beall, Bernard W.; Cordeiro, Soraia M.; Takahashi, Daniele; Reis, Mitermayer G.; Ko, Albert I.; Reis, Joice N.

2009-01-01

The newly described Streptococcus pneumoniae serotype 6C accounted for 2.3% (16/709) of meningitis cases and 3.2% (3/95) of nasopharyngeal isolates from healthy individuals in Brazil. The strains were multidrug resistant (18.8%) and genetically diverse. Despite low serotype 6C prevalence, continuous surveillance is necessary to guide vaccine strategies. PMID:19709842

Serotype Distribution and Drug Resistance in Streptococcus pneumoniae, Palestinian Territories

PubMed Central

Kattan, Randa; Abu Rayyan, Amal; Zheiman, Inas; Idkeidek, Suzan; Baraghithi, Sabri; Rishmawi, Nabeel; Turkuman, Sultan; Abu-Diab, Afaf; Ghneim, Riyad; Zoughbi, Madeleine; Dauodi, Rula; Ghneim, Raed; Issa, Abed-El-Razeq; Siryani, Issa; Al Qas, Randa; Liddawi, Rawan; Khamash, Hatem; Kanaan, Moein; Marzouqa, Hiyam

2011-01-01

To determine antimicrobial drug resistance of Streptococcus pneumoniae serotypes, we analyzed isolates from blood cultures of sick children residing in the West Bank before initiation of pneumococcal vaccination. Of 120 serotypes isolated, 50.8%, 73.3%, and 80.8% of the bacteremia cases could have been prevented by pneumococcal conjugate vaccines. Serotype 14 was the most drug-resistant serotype isolated. PMID:21192863

Production of capsular polysaccharide of Streptococcus pneumoniae type 14 and its purification by affinity chromatography.

PubMed

Suárez, N; Fraguas, L F; Texeira, E; Massaldi, H; Batista-Viera, F; Ferreira, F

2001-02-01

We describe a rapid and efficient method for producing the capsular polysaccharide of Streptococcus pneumoniae by fermentation on tryptic soy broth and purification of this compound by using immobilized soybean lectin as an affinity adsorbent. In principle, the same strategy can be used to produce purified capsular polysaccharides from other streptococcal serotypes by selecting the appropriate lectin adsorbents.

Production of Capsular Polysaccharide of Streptococcus pneumoniae Type 14 and Its Purification by Affinity Chromatography

PubMed Central

Suárez, Norma; Fraguas, Laura Franco; Texeira, Esther; Massaldi, Hugo; Batista-Viera, Francisco; Ferreira, Fernando

2001-01-01

We describe a rapid and efficient method for producing the capsular polysaccharide of Streptococcus pneumoniae by fermentation on tryptic soy broth and purification of this compound by using immobilized soybean lectin as an affinity adsorbent. In principle, the same strategy can be used to produce purified capsular polysaccharides from other streptococcal serotypes by selecting the appropriate lectin adsorbents. PMID:11157270

Acute suppurative parotitis caused by Streptococcus pneumoniae in an HIV-infected man.

PubMed

Guzman Vinasco, Luis; Bares, Sara; Sandkovsky, Uriel

2015-03-02

We report a case of a 32-year-old man who presented with progressive unilateral parotid gland enlargement and subsequently tested positive for HIV. A CT scan of the neck performed with contrast showed a phlegmon in the region of the right parotid tail measuring approximately 2.5×2.4 cm. Cultures of the aspirated fluid grew Streptococcus pneumoniae and the S. pneumoniae urinary antigen test was also positive. The patient underwent surgical debridement and received antimicrobial therapy with complete resolution of the parotitis. Parotitis caused by S. pneumoniae is rare, and HIV infection should be suspected in any case of invasive pneumococcal disease. 2015 BMJ Publishing Group Ltd.

Acute suppurative parotitis caused by Streptococcus pneumoniae in an HIV-infected man

PubMed Central

Guzman Vinasco, Luis; Bares, Sara; Sandkovsky, Uriel

2015-01-01

We report a case of a 32-year-old man who presented with progressive unilateral parotid gland enlargement and subsequently tested positive for HIV. A CT scan of the neck performed with contrast showed a phlegmon in the region of the right parotid tail measuring approximately 2.5×2.4 cm. Cultures of the aspirated fluid grew Streptococcus pneumoniae and the S. pneumoniae urinary antigen test was also positive. The patient underwent surgical debridement and received antimicrobial therapy with complete resolution of the parotitis. Parotitis caused by S. pneumoniae is rare, and HIV infection should be suspected in any case of invasive pneumococcal disease. PMID:25733094

Etiology of acute otitis media and serotype distribution of Streptococcus pneumoniae and Haemophilus influenzae in Chilean children <5 years of age

PubMed Central

Rosenblut, Andres; Napolitano, Carla; Pereira, Angelica; Moreno, Camilo; Kolhe, Devayani; Lepetic, Alejandro; Ortega-Barria, Eduardo

2017-01-01

Abstract The impact of bacterial conjugate vaccines on acute otitis media (AOM) is affected by several factors including population characteristics, bacterial etiology and vaccine conjugation method, carrier, and coverage. This study estimated the baseline etiology, distribution, and antibiotic susceptibility of bacterial serotypes that causes AOM in children aged <5 years in a public setting in Santiago, Chile. Children aged ≥3 months and <5 years referred to the physician for treatment of AOM episodes (with an onset of symptoms <72 h) were enrolled between September 2009 and September 2010. Middle ear fluid (MEF) was collected by tympanocentesis or by otorrhea for identification and serotyping of bacteria. Antibacterial susceptibility was tested using E-test (etrack: 112671). Of 160 children (mean age 27.10 ± 15.83 months) with AOM episodes, 164 MEF samples (1 episode each from 156 children; 2 episodes each from 4 children) were collected. Nearly 30% of AOM episodes occurred in children aged 12 to 23 months. Streptococcus pneumoniae (41.7% [58/139]) and Haemophilus influenzae (40.3% [56/139]) were predominant among the cultures that showed bacterial growth (85% [139/164]). All Streptococcus pneumoniae positive episodes were serotyped, 19F (21%) and 14 (17%) were the predominant serotypes; all Haemophilus influenzae strains were nontypeable. Streptococcus pneumoniae were resistant to penicillin (5%) and erythromycin (33%); Haemophilus influenzae were resistant to ampicillin (14%) and cefuroxime and cefotaxime (2% each). AOM in Chilean children is predominantly caused by Streptococcus pneumoniae and nontypeable Haemophilus influenzae. Use of a broad spectrum vaccine against these pathogens might aid the reduction of AOM in Chile. PMID:28178138

Structure of a quinolone-stabilized cleavage complex of topoisomerase IV from Klebsiella pneumoniae and comparison with a related Streptococcus pneumoniae complex

PubMed Central

Veselkov, Dennis A.; Laponogov, Ivan; Pan, Xiao-Su; Selvarajah, Jogitha; Skamrova, Galyna B.; Branstrom, Arthur; Narasimhan, Jana; Prasad, Josyula V. N. Vara; Fisher, L. Mark; Sanderson, Mark R.

2016-01-01

Klebsiella pneumoniae is a Gram-negative bacterium that is responsible for a range of common infections, including pulmonary pneumonia, bloodstream infections and meningitis. Certain strains of Klebsiella have become highly resistant to antibiotics. Despite the vast amount of research carried out on this class of bacteria, the molecular structure of its topoisomerase IV, a type II topoisomerase essential for catalysing chromosomal segregation, had remained unknown. In this paper, the structure of its DNA-cleavage complex is reported at 3.35 Å resolution. The complex is comprised of ParC breakage-reunion and ParE TOPRIM domains of K. pneumoniae topoisomerase IV with DNA stabilized by levofloxacin, a broad-spectrum fluoroquinolone antimicrobial agent. This complex is compared with a similar complex from Streptococcus pneumoniae, which has recently been solved. PMID:27050128

21 CFR 520.90d - Ampicillin trihydrate for oral suspension.

Code of Federal Regulations, 2011 CFR

2011-04-01

...., Staphylococcus spp., and Streptococcus spp., urinary tract infections (cystitis) due to E. coli, Staphylococcus spp., Streptococcus spp., and Proteus spp.; bacterial gastroenteritis due to E. coli; generalized... (bacterial pneumonia) due to Staphylococcus spp., Streptococcus spp., E. coli, and Proteus spp.; urinary...

21 CFR 520.90d - Ampicillin trihydrate for oral suspension.

Code of Federal Regulations, 2010 CFR

2010-04-01

...., Staphylococcus spp., and Streptococcus spp., urinary tract infections (cystitis) due to E. coli, Staphylococcus spp., Streptococcus spp., and Proteus spp.; bacterial gastroenteritis due to E. coli; generalized... (bacterial pneumonia) due to Staphylococcus spp., Streptococcus spp., E. coli, and Proteus spp.; urinary...

Meningitis - pneumococcal

MedlinePlus

Pneumococcal meningitis is caused by Streptococcus pneumoniae bacteria (also called pneumococcus, or S pneumoniae ). This type of bacteria is the most common cause of bacterial meningitis in adults. ...

Community acquired bacterial pneumonia: aetiology, laboratory detection and antibiotic susceptibility pattern.

PubMed

Akter, Sonia; Shamsuzzaman, S M; Jahan, Ferdush

2014-08-01

This cross sectional study was conducted to identify the common bacterial causes of community acquired pneumonia (CAP) from sputum and blood by culture and polymerase chain reaction (PCR) and to evaluate the effectiveness of these tests. A total of 105 sputum and blood samples were collected from patients with pneumonia on clinical suspicion. Common causative bacterial agents of pneumonia were detected by Gram staining, cultures, biochemical tests and PCR. Among 55 sputum culture positive cases, a majority (61.82%) of the patients were in the age group between 21-50 years and the ratio between male and female was 2.5:1. Most (61.90%) of the cases were from the lower socio-economic group. Out of 105 samples, 23 (37.12%) were positive by Gram stain, 29 (27.62%) yielded growth in culture media and 37 (35.24%) were positive by PCR for Streptococcus pneumoniae and Haemophilus influenzae. Streptococcus pneumoniae was the most common aetiological agent (19.05%) followed by Klebsiella pneumoniae (13.33%), Haemophilus influenzae (8.57%) and Pseudomonas aeruginosa (5.71%). Multiplex PCR is a useful technique for rapid diagnosis of bacterial causes of pneumonia directly from sputum and blood. Considering culture as a gold standard, the sensitivity of PCR was 96.55% and specificity was 88.15%. More than 80% of Streptococcus pneumoniae isolates were found to be sensitive to ampicillin, amoxycillinclavulanate, and ceftriaxone. Susceptibilities to other antimicrobials ranged from 65% for azithromycin to 70% for levofloxacin. On the other hand, the Gram negative organisms were more sensitive to meropenem, ceftriaxone, amoxycillin-clavulanate and amikacin.

Analysis of invasive pneumonia-causing strains of Streptococcus pneumoniae: serotypes and antimicrobial susceptibility.

PubMed

Yoshioka, Cristina R M; Martinez, Marina B; Brandileone, Maria C C; Ragazzi, Selma B; Guerra, Maria L L S; Santos, Silvia R; Shieh, Huei H; Gilio, Alfredo E

2011-01-01

To identify the most common pneumococcal serotypes in children hospitalized with invasive pneumonia, correlate isolated serotypes with those included in conjugate vaccines, and ascertain the sensitivity of the isolated pneumococcal strains to penicillin and other antibiotics. From January 2003 to October 2008, a retrospective study of hospitalized children with a diagnosis of Streptococcus pneumoniae pneumonia was conducted at the university hospital of Universidade de São Paulo. Criteria for inclusion were: age greater than 29 days and less than 15 years, radiological and clinical diagnosis of pneumonia, and isolation of Streptococcus pneumoniae in blood cultures and/or pleural effusion. The study included 107 children. The most common serotypes were 14 (36.5%), 1 (16%), 5 (14.6%), 6B (6.3%) and 3 (4.2%). The proportion of identified serotypes contained in the heptavalent, 10-valent and 13-valent conjugate vaccines was 53.1, 86.5, and 96.9%, respectively. Pneumococcal strains were sensitive to penicillin (minimum inhibitory concentration, MIC ≤ 2 µg/mL) in 100 cases (93.5%) and displayed intermediate resistance (MIC = 4 µg/mL) in 7 cases (6.5%). No strains were penicillin-resistant (MIC ≥ 8 µg/mL) according to the Clinical and Laboratory Standards Institute 2008 standards. Tested isolates were highly sensitive to vancomycin, rifampicin, ceftriaxone, clindamycin, erythromycin, and chloramphenicol. Our results confirm a significant potential impact of conjugate vaccines, mainly 10-valent and 13-valent, on invasive pneumonia. Furthermore, susceptibility testing results show that penicillin is still the treatment of choice for invasive pneumonia in our setting.

Increased Nasopharyngeal Density and Concurrent Carriage of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis Are Associated with Pneumonia in Febrile Children.

PubMed

Chochua, Sopio; D'Acremont, Valérie; Hanke, Christiane; Alfa, David; Shak, Joshua; Kilowoko, Mary; Kyungu, Esther; Kaiser, Laurent; Genton, Blaise; Klugman, Keith P; Vidal, Jorge E

2016-01-01

We assessed nasopharyngeal (NP) carriage of five pathogens in febrile children with and without acute respiratory infection (ARI) of the upper (URTI) or lower tract, attending health facilities in Tanzania. NP swabs collected from children (N = 960) aged 2 months to 10 years, and with a temperature ≥38°C, were utilized to quantify bacterial density of S. pneumoniae (Sp), H. influenzae (Hi), M. catarrhalis (Mc), S. aureus (Sa), and N. meningitidis (Nm). We determined associations between presence of individual species, densities, or concurrent carriage of all species combination with respiratory diseases including clinical pneumonia, pneumonia with normal chest radiography (CXR) and endpoint pneumonia. Individual carriage, and NP density, of Sp, Hi, or Mc, but not Sa, or Nm, was significantly associated with febrile ARI and clinical pneumonia when compared to febrile non-ARI episodes. Density was also significantly increased in severe pneumonia when compared to mild URTI (Sp, p<0.002; Hi p<0.001; Mc, p = 0.014). Accordingly, concurrent carriage of Sp+, Hi+, and Mc+, in the absence of Sa- and Nm-, was significantly more prevalent in children with ARI (p = 0.03), or clinical pneumonia (p<0.001) than non-ARI, and in children with clinical pneumonia (p = 0.0007) than URTI. Furthermore, Sp+, Hi+, and Mc+ differentiated children with pneumonia with normal CXR, or endpoint pneumonia, from those with URTI, and non-ARI cases. Concurrent NP carriage of Sp, Hi, and Mc was a predictor of clinical pneumonia and identified children with pneumonia with normal CXR and endpoint pneumonia from those with febrile URTI, or non-ARI episodes.

Increased Nasopharyngeal Density and Concurrent Carriage of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis Are Associated with Pneumonia in Febrile Children

PubMed Central

2016-01-01

Background We assessed nasopharyngeal (NP) carriage of five pathogens in febrile children with and without acute respiratory infection (ARI) of the upper (URTI) or lower tract, attending health facilities in Tanzania. Methods NP swabs collected from children (N = 960) aged 2 months to 10 years, and with a temperature ≥38°C, were utilized to quantify bacterial density of S. pneumoniae (Sp), H. influenzae (Hi), M. catarrhalis (Mc), S. aureus (Sa), and N. meningitidis (Nm). We determined associations between presence of individual species, densities, or concurrent carriage of all species combination with respiratory diseases including clinical pneumonia, pneumonia with normal chest radiography (CXR) and endpoint pneumonia. Results Individual carriage, and NP density, of Sp, Hi, or Mc, but not Sa, or Nm, was significantly associated with febrile ARI and clinical pneumonia when compared to febrile non-ARI episodes. Density was also significantly increased in severe pneumonia when compared to mild URTI (Sp, p<0.002; Hi p<0.001; Mc, p = 0.014). Accordingly, concurrent carriage of Sp+, Hi+, and Mc+, in the absence of Sa- and Nm-, was significantly more prevalent in children with ARI (p = 0.03), or clinical pneumonia (p<0.001) than non-ARI, and in children with clinical pneumonia (p = 0.0007) than URTI. Furthermore, Sp+, Hi+, and Mc+ differentiated children with pneumonia with normal CXR, or endpoint pneumonia, from those with URTI, and non-ARI cases. Conclusions Concurrent NP carriage of Sp, Hi, and Mc was a predictor of clinical pneumonia and identified children with pneumonia with normal CXR and endpoint pneumonia from those with febrile URTI, or non-ARI episodes. PMID:27907156

In Vitro Activity of Delafloxacin Tested against Isolates of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis

PubMed Central

Rhomberg, Paul R.; Huband, Michael D.; Farrell, David J.

2016-01-01

Delafloxacin, an investigational anionic fluoroquinolone, is active against a broad range of Gram-positive and Gram-negative bacteria. In this study, 200 Streptococcus pneumoniae (plus 30 levofloxacin-resistant isolates), 200 Haemophilus influenzae, and 100 Moraxella catarrhalis isolates selected primarily from the United States (2014) were tested against delafloxacin and comparator agents. Delafloxacin was the most potent agent tested. MIC50 and MIC90 values against all S. pneumoniae isolates were 0.008 and 0.015 μg/ml. Delafloxacin susceptibility was not affected by β-lactamase status against H. influenzae and M. catarrhalis. PMID:27458220

A comparison of a new oral streptogramin XRP 2868 with quinupristin-dalfopristin against antibiotic-resistant strains of haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae.

PubMed

Mabe, Susan; Champney, W Scott

2005-12-01

A new streptogramin antibiotic XRP 2868 was compared with quinupristin-dalfopristin for inhibitory activities against antibiotic-resistant Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae. In each organism examined, XRP 2868 had an IC(50) that was twofold to fivefold lower than quinupristin-dalfopristin, for inhibition of cell viability, protein synthesis, and ribosomal subunit formation.

Colonization of hydrogel lenses with Streptococcus pneumoniae: risk of development of corneal infiltrates.

PubMed

Sankaridurg, P R; Sharma, S; Willcox, M; Sweeney, D F; Naduvilath, T J; Holden, B A; Rao, G N

1999-05-01

To report the association between colonization of contact lenses with Streptococcus pneumoniae and the observation of corneal infiltrative events in a group of patients wearing disposable hydrogel lenses on an extended-wear schedule. In a prospective clinical trial, 330 patients wore disposable hydrogels on a 6-night extended-wear and replacement schedule. The contact lens, lid, and conjunctival microbiota of these subjects was analyzed at frequent intervals and at the time of an adverse event. Streptococcus pneumoniae was an uncommon isolate and was recovered from only one of the 3,763 conjunctival samples, five (0.1%) of the 3,764 lid samples, and 33 (0.8%) of the 4,315 contact lens samples. Of the 33 lens samples, 10 (30%) were associated with corneal infiltrative events. Many of the events were mild inflammatory responses and resolved rapidly on discontinuation of lens wear. The presence of S. pneumoniae on the contact lens was associated with a significant risk of development of corneal infiltrates (odds ratio, 3.0; p = 0.0227, logistic-regression analysis). Presence of S. pneumoniae on hydrogel lenses is a significant risk factor for the development of corneal infiltrates.

Characterization of Streptococcus pneumoniae N-acetylglucosamine-6-phosphate deacetylase as a novel diagnostic marker.

PubMed

Choi, Chi-Won; An, Hee-Young; Lee, Yong Ju; Lee, Yeol Gyun; Yun, Sung Ho; Park, Edmond Changkyun; Hong, Yeonhee; Kim, Gun-Hwa; Park, Jae-Eun; Baek, Sun Jong; Kim, Hyun Sik; Kim, Seung Il

2013-10-01

The identification of novel diagnostic markers of pathogenic bacteria is essential for improving the accuracy of diagnoses and for developing targeted vaccines. Streptococcus pneumoniae is a significant human pathogenic bacterium that causes pneumonia. N-acetylglucosamine-6-phosphate deacetylase (NagA) was identified in a protein mixture secreted by S. pneumoniae and its strong immunogenicity was confirmed in an immuno-proteomic assay against the anti-serum of the secreted protein mixture. In this study, recombinant S. pneumoniae NagA protein was expressed and purified to analyze its protein characteristics, immunospecificity, and immunogenicity, thereby facilitating its evaluation as a novel diagnostic marker for S. pneumoniae. Mass spectrometry analysis showed that S. pneumoniae NagA contains four internal disulfide bonds and that it does not undergo post-translational modification. S. pneumoniae NagA antibodies successfully detected NagA from different S. pneumoniae strains, whereas NagA from other pathogenic bacteria species was not detected. In addition, mice infected with S. pneumoniae generated NagA antibodies in an effective manner. These results suggest that NagA has potential as a novel diagnostic marker for S. pneumoniae because of its high immunogenicity and immunospecificity.

Differentiation of Streptococcus pneumoniae Conjunctivitis Outbreak Isolates by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry▿

PubMed Central

Williamson, Yulanda M.; Moura, Hercules; Woolfitt, Adrian R.; Pirkle, James L.; Barr, John R.; Carvalho, Maria Da Gloria; Ades, Edwin P.; Carlone, George M.; Sampson, Jacquelyn S.

2008-01-01

Streptococcus pneumoniae (pneumococcus [Pnc]) is a causative agent of many infectious diseases, including pneumonia, septicemia, otitis media, and conjunctivitis. There have been documented conjunctivitis outbreaks in which nontypeable (NT), nonencapsulated Pnc has been identified as the etiological agent. The use of mass spectrometry to comparatively and differentially analyze protein and peptide profiles of whole-cell microorganisms remains somewhat uncharted. In this report, we discuss a comparative proteomic analysis between NT S. pneumoniae conjunctivitis outbreak strains (cPnc) and other known typeable or NT pneumococcal and streptococcal isolates (including Pnc TIGR4 and R6, Streptococcus oralis, Streptococcus mitis, Streptococcus pseudopneumoniae, and Streptococcus pyogenes) and nonstreptococcal isolates (including Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus) as controls. cPnc cells and controls were grown to mid-log phase, harvested, and subsequently treated with a 10% trifluoroacetic acid-sinapinic acid matrix mixture. Protein and peptide fragments of the whole-cell bacterial isolate-matrix combinations ranging in size from 2 to 14 kDa were evaluated by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Additionally Random Forest analytical tools and dendrogramic representations (Genesis) suggested similarities and clustered the isolates into distinct clonal groups, respectively. Also, a peak list of protein and peptide masses was obtained and compared to a known Pnc protein mass library, in which a peptide common and unique to cPnc isolates was tentatively identified. Information gained from this study will lead to the identification and validation of proteins that are commonly and exclusively expressed in cPnc strains which could potentially be used as a biomarker in the rapid diagnosis of pneumococcal conjunctivitis. PMID:18708515

Case-control study of pneumonia patients with Streptococcus anginosus group bacteria in their sputum.

PubMed

Hirai, Jun; Sakanashi, Daisuke; Haranaga, Shusaku; Kinjo, Takeshi; Hagihara, Mao; Kato, Hideo; Suematsu, Hiroyuki; Yamagishi, Yuka; Fujita, Jiro; Mikamo, Hiroshige

2016-12-01

In recent years, Streptococcus anginosus group (SAG) bacteria are becoming increasingly recognized as important pneumonia-causing pathogens. Although several small studies have been reported, the features of SAG pneumonia remain unclear, because the identification of SAG from sputum cultures is not routinely performed in most microbiology laboratories. The aim of this study was to elucidate the clinical characteristics of SAG pneumonia. This was a retrospective case-control study utilizing data obtained in our hospital between September 2009 and June 2016. We investigated 31 patients with SAG pneumonia (PWP), and also assessed the difference between the 31 PWP and 37 patients without pneumonia (PWOP) in whose sputum SAG was detected. Seventy-one percent of the patients were men and the median age was 78 years in the PWP. Univariate analysis indicated that the PWP were significantly more often a bed-ridden (p < 0.01) with comorbid aspiration than were the PWOP (p < 0.05). Among the PWP, nursing and healthcare-associated pneumonia (NHCAP) was the more common type of pneumonia (54.8%). S. anginosus was detected significantly more frequently in sputum cultures of PWP than PWOP (p < 0.01), and multiple pathogens were detected more frequently in PWP (p < 0.01). Streptococcus constellatus was the most frequently detected pathogen in patients with a single bacterial infection. Empyema was observed only in patients with multiple bacteria. SAG should be recognized as important causative pathogens of pneumonia, particularly among elderly patients with underlying disease associated with aspiration. NHCAP was the more common type of SAG pneumonia in this study. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Identification of the psaA Gene, Coding for Pneumococcal Surface Adhesin A, in Viridans Group Streptococci other than Streptococcus pneumoniae

PubMed Central

Jado, Isabel; Fenoll, Asunción; Casal, Julio; Pérez, Amalia

2001-01-01

The gene encoding the pneumococcal surface adhesin A (PsaA) protein has been identified in three different viridans group streptococcal species. Comparative studies of the psaA gene identified in different pneumococcal isolates by sequencing PCR products showed a high degree of conservation among these strains. PsaA is encoded by an open reading frame of 930 bp. The analysis of this fragment in Streptococcus mitis, Streptococcus oralis, and Streptococcus anginosus strains revealed a sequence identity of 95, 94, and 90%, respectively, to the corresponding open reading frame of the previously reported Streptococcus pneumoniae serotype 6B strain. Our results confirm that psaA is present and detectable in heterologous bacterial species. The possible implications of these results for the suitability and potential use of PsaA in the identification and diagnosis of pneumococcal diseases are discussed. PMID:11527799

21 CFR 520.2260a - Sulfamethazine oblet, tablet, and bolus.

Code of Federal Regulations, 2010 CFR

2010-04-01

... and nonlactating dairy cattle. Treatment of bacterial pneumonia and bovine respiratory disease complex... mastitis (Streptococcus spp.), acute metritis (Streptococcus spp.), coccidiosis (Eimeria bovis and Eimeria...

Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae.

PubMed

Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong; Tettelin, Hervé; Kilian, Mogens

2016-11-15

Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. Expression of a capsular polysaccharide is among the principal virulence factors of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species of streptococci that form a significant part of our commensal microbiota. The demonstrated antigenic identity of many capsular polysaccharides expressed by commensal streptococci and S. pneumoniae raises important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and the pathogen. Copyright © 2016 Skov Sørensen et al.

Mutations in the tacF gene of clinical strains and laboratory transformants of Streptococcus pneumoniae: impact on choline auxotrophy and growth rate.

PubMed

González, Ana; Llull, Daniel; Morales, María; García, Pedro; García, Ernesto

2008-06-01

The nutritional requirement that Streptococcus pneumoniae has for the aminoalcohol choline as a component of teichoic and lipoteichoic acids appears to be exclusive to this prokaryote. A mutation in the tacF gene, which putatively encodes an integral membrane protein (possibly, a teichoic acid repeat unit transporter), has been recently identified as responsible for generating a choline-independent phenotype of S. pneumoniae (M. Damjanovic, A. S. Kharat, A. Eberhardt, A. Tomasz, and W. Vollmer, J. Bacteriol. 189:7105-7111, 2007). We now report that Streptococcus mitis can grow in choline-free medium, as previously illustrated for Streptococcus oralis. While we confirmed the finding by Damjanovic et al. of the involvement of TacF in the choline dependence of the pneumococcus, the genetic transformation of S. pneumoniae R6 by using S. mitis SK598 DNA and several PCR-amplified tacF fragments suggested that a minimum of two mutations were required to confer improved fitness to choline-independent S. pneumoniae mutants. This conclusion is supported by sequencing results also reported here that indicate that a spontaneous mutant of S. pneumoniae (strain JY2190) able to proliferate in the absence of choline (or analogs) is also a double mutant for the tacF gene. Microscopic observations and competition experiments during the cocultivation of choline-independent strains confirmed that a minimum of two amino acid changes were required to confer improved fitness to choline-independent pneumococcal strains when growing in medium lacking any aminoalcohol. Our results suggest complex relationships among the different regions of the TacF teichoic acid repeat unit transporter.

Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae

PubMed Central

Skov Sørensen, Uffe B.; Yao, Kaihu; Yang, Yonghong; Tettelin, Hervé

2016-01-01

ABSTRACT Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis. Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. PMID:27935839

21 CFR 520.2261a - Sulfamethazine sodium drinking water solution.

Code of Federal Regulations, 2010 CFR

2010-04-01

... nonlactating dairy cattle. Treatment of bacterial pneumonia and bovine respiratory disease complex (shipping... mastitis (Streptococcus spp.), and acute metritis (Streptococcus spp.). (ii) Swine. Treatment of porcine...

Streptococcus pneumoniae endocarditis on replacement aortic valve with panopthalmitis and pseudoabscess

PubMed Central

O’Brien, Stephen; Dayer, Mark; Benzimra, James; Hardman, Susan; Townsend, Mandie

2011-01-01

A 63-year-old woman with a previous episode of Streptococcus agalactiae endocarditis requiring a bioprosthetic aortic valve replacement presented with a short history of malaise, a right panopthalmitis with a Roth spot on funduscopy of the left eye and Streptococcus pneumoniae grown from vitreous and aqueous taps as well as blood cultures. She developed first degree heart block and her ECG was suggestive of an aortic root abscess. This gradually resolved over 6 weeks, during which she was treated with intravenous antibiotics. After careful consideration, it is likely that what was thought to be an aortic root abscess was instead an area of perivalvular inflammation. PMID:22678733

The Importance of TLR2 and Macrophages in Modulating a Humoral Response after Encountering Streptococcus pneumoniae

DTIC Science & Technology

2008-03-26

Response after Encountering Streptococcus Pneumoniae" Brian Schae:5 ,Ph.D. Department of Microbi ogy & Immunology Committee Chairperson Masters...presenting cells (APCs), such as macrophages (M ) and dendritic cells (DC) recognize microbial surface components via cell surface receptors (i.e...stimulating factor (GM-CSF). TH1 cells are able to secrete IFN- , which is important in activating M to produce mediators important for microbial

Neutrophil evasion strategies by Streptococcus pneumoniae and Staphylococcus aureus.

PubMed

Lewis, Megan L; Surewaard, Bas G J

2018-03-01

Humans are well equipped to defend themselves against bacteria. The innate immune system employs diverse mechanisms to recognize, control and initiate a response that can destroy millions of different microbes. Microbes that evade the sophisticated innate immune system are able to escape detection and could become pathogens. The pathogens Streptococcus pneumoniae and Staphylococcus aureus are particularly successful due to the development of a wide variety of virulence strategies for bacterial pathogenesis and they invest significant efforts towards mechanisms that allow for neutrophil evasion. Neutrophils are a primary cellular defense and can rapidly kill invading microbes, which is an indispensable function for maintaining host health. This review compares the key features of Streptococcus pneumoniae and Staphylococcus aureus in epidemiology, with a specific focus on virulence mechanisms utilized to evade neutrophils in bacterial pathogenesis. It is important to understand the complex interactions between pathogenic bacteria and neutrophils so that we can disrupt the ability of pathogens to cause disease.

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

Insights into the Evolutionary Relationships of LytA Autolysin and Ply Pneumolysin-Like Genes in Streptococcus pneumoniae and Related Streptococci

PubMed Central

Morales, María; Martín-Galiano, Antonio J.; Domenech, Mirian; García, Ernesto

2015-01-01

Streptococcus pneumoniae (pneumococcus) is a major human pathogen. The main pneumococcal autolysin LytA and the pneumolysin Ply are two of the bacterium’s most important virulence factors. The lytA- and ply-related genes are also found in other streptococci of the Mitis group (SMG). The precise characteristics of the lytA-related—but not the ply-related—genes of SMG and their prophages have been previously described. A search of the more than 400 SMG genomic sequences available in public databases (ca. 300 for S. pneumoniae), showed Streptococcus pseudopneumoniae IS7493 to harbor four ply-related genes, two of which (plyA and plyB) have 98% identical nucleotides. The plyA homolog of S. pseudopneumoniae is conserved in all S. pneumoniae strains, and seems to be included in a pathogenicity island together with the lytA gene. However, only nonencapsulated S. pneumoniae strains possess a plyB gene, which is part of an integrative and conjugative element. Notably, the existence of a bacterial lytA-related gene in a genome is linked to the presence of plyA and vice versa. The present analysis also shows there are eight main types of plyA−lytA genomic islands. A possible stepwise scenario for the evolution of the plyA−lytA island in S. pneumoniae is proposed. PMID:26349755

In Vitro Activity of Delafloxacin Tested against Isolates of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

PubMed

Flamm, Robert K; Rhomberg, Paul R; Huband, Michael D; Farrell, David J

2016-10-01

Delafloxacin, an investigational anionic fluoroquinolone, is active against a broad range of Gram-positive and Gram-negative bacteria. In this study, 200 Streptococcus pneumoniae (plus 30 levofloxacin-resistant isolates), 200 Haemophilus influenzae, and 100 Moraxella catarrhalis isolates selected primarily from the United States (2014) were tested against delafloxacin and comparator agents. Delafloxacin was the most potent agent tested. MIC50 and MIC90 values against all S. pneumoniae isolates were 0.008 and 0.015 μg/ml. Delafloxacin susceptibility was not affected by β-lactamase status against H. influenzae and M. catarrhalis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vitro bactericidal and bacteriolytic activity of ceragenin CSA-13 against planktonic cultures and biofilms of Streptococcus pneumoniae and other pathogenic streptococci.

PubMed

Moscoso, Miriam; Esteban-Torres, María; Menéndez, Margarita; García, Ernesto

2014-01-01

Ceragenin CSA-13, a cationic steroid, is here reported to show a concentration-dependent bactericidal/bacteriolytic activity against pathogenic streptococci, including multidrug-resistant Streptococcus pneumoniae. The autolysis promoted by CSA-13 in pneumococcal cultures appears to be due to the triggering of the major S. pneumoniae autolysin LytA, an N-acetylmuramoyl-L-alanine amidase. CSA-13 also disintegrated pneumococcal biofilms in a very efficient manner, although at concentrations slightly higher than those required for bactericidal activity on planktonic bacteria. CSA-13 has little hemolytic activity which should allow testing its antibacterial efficacy in animal models.

Treatment with protein synthesis inhibitors improves outcomes from secondary bacterial pneumonia following influenza

PubMed Central

Karlström, Åsa; Boyd, Kelli L.; English, B. Keith; McCullers, Jonathan A.

2008-01-01

Pneumonia as a secondary infection after influenza is a major cause of excess morbidity and mortality despite the availability and use of antibiotics active against Streptococcus pneumoniae. We hypothesized that use of a bacteriostatic protein synthesis inhibitor would improve outcomes by reducing the inflammatory response. BALB/c mice infected with influenza virus and super-infected with Streptococcus pneumoniae were treated with either the cell wall active antibiotic ampicillin or protein synthesis inhibitors clindamycin or azithromycin. Ampicillin therapy performed significantly worse (56% survival) in the model compared to clindamycin therapy either alone (82%) or in combination with ampicillin (80%) and to azithromycin (92%). Improved survival appeared to be mediated by decreased inflammation manifested as lower levels of inflammatory cells and pro-inflammatory cytokines in the lungs, and less severe histopathology. These data suggest that beta-lactam therapy may not be optimal as first line treatment of community acquired pneumonia when it follows influenza. PMID:19113989

Phenotypic and genotypic discrepancy of Streptococcus pneumoniae strains isolated from Asian countries.

PubMed

Ko, Kwan Soo; Oh, Won Sup; Peck, Kyong Ran; Lee, Jang Ho; Lee, Nam Yong; Song, Jae-Hoon

2005-07-01

Non-typeable isolates of Streptococcus pneumoniae collected from Asian countries were characterized by optochin susceptibility test, bile solubility test, multilocus sequence typing of housekeeping genes, amplification of virulence-related genes, 16S rDNA-RsaI digestion, and 16S rDNA sequencing. Six of 54 non-typeable pneumococcal isolates showed divergence of gene sequences of recP and xpt from typical pneumococcal strains. Of these six atypical pneumococcal strains, two showed different results in optochin susceptibility or bile solubility test from typical pneumococcal strains. All six isolates showed high sequence dissimilarities of multilocus sequence typing, 16S rDNA sequences, and lytA sequences from typical S. pneumoniae strains. Data from this study suggest that classic tests such as optochin susceptibility and bile solubility tests may lead to incorrect identification of S. pneumoniae. These atypical strains may belong to different bacterial species from S. pneumoniae.

Microfloral diversity in the lower respiratory tracts of neonates with bacterial infectious pneumonia combined with ventilator‑associated pneumonia.

PubMed

Lu, Wei; Yu, Jia-Lin; Li, Lu-Quan; Lu, Qi; Wang, Zheng-Li; Pan, Yun

2016-12-01

Bacterial infectious pneumonia is one of the major causes of mortality in neonates, particularly when the neonates suffer from ventilator‑associated pneumonia (VAP). However, the causes of pneumonia are difficult to define. Thus, the present study focused on understanding the diversity of microflora in the lower respiratory tract to elucidate the causes. The experimental groups comprised newborns who suffered from infectious pneumonia with or without VAP (IVAP and IP groups, respectively), whereas the control group comprised newborns who suffered from respiratory distress syndrome (RDS) without VAP (RDS group). Following 1, 3 and 5 days of ventilation, sputum samples were collected and the DNA was extracted. The DNA was amplified and separated, and the 16S rDNA was then sequenced and analyzed for diversity. The results of the diversity and Shannon‑Wiener indices were ordered as follows: IVAP group < IP group < RDS group. The percentages of Streptococcus sp., Serratia sp. and Achromobacter sp. in the IP and IVAP groups were higher, compared with those in the RDS group, whereas the percentages of Klebsiella sp. and Acinetobacter sp. were lower on day 1. The percentages of Klebsiella sp. and Streptococcus sp. on days 1 and 3 were ordered as follows: IVAP group > IP group > RDS group, and the percentages of Serratia sp., Acinetobacter sp. and Achromobacter sp. were ordered as follows: IVAP group < IP group < RDS group. After 3‑5 days, the percentages of Klebsiella sp., Acinetobacter sp., Streptococcus sp., Serratia sp. and Achromobacter sp. in the IVAP group were lower, compared with those in the RDS and IP groups. It was concluded that the decreased microfloral diversity, increased constituent ratios of Klebsiella sp. and Streptococcus sp., and decreased ratios of Serratia sp. and Acinetobacter sp. in the lower respiratory tract of neonates suffering from pneumonia may be indicators of VAP.

Comparative in-vitro activities of quinupristin-dalfopristin against Gram-positive bloodstream isolates.

PubMed

Schouten, M A; Hoogkamp-Korstanje, J A

1997-08-01

The in-vitro activity of quinupristin-dalfopristin was compared with those of vancomycin, teicoplanin, erythromycin, clarithromycin, rifampicin, imipenem, meropenem, ciprofloxacin and sparfloxacin against 414 bloodstream isolates of Gram-positive cocci. Quinupristin-dalfopristin inhibited strains of Streptococcus pyogenes and Streptococcus agalactiae at 0.12 mg/L, methicillin- and/or erythromycin-resistant Staphylococcus aureus and Staphylococcus epidermidis at 0.5 mg/L, Staphylococcus haemolyticus, Enterococcus faecium, Streptococcus pneumoniae, Streptococcus mitis, Streptococcus bovis, Streptococcus sanguis and Streptococcus anginosus at 1 mg/L and Enterococcus faecalis at 8 mg/L.

Streptococcus pneumoniae-associated pneumonia complicated by purulent pericarditis: case series *

PubMed Central

Cillóniz, Catia; Rangel, Ernesto; Barlascini, Cornelius; Piroddi, Ines Maria Grazia; Torres, Antoni; Nicolini, Antonello

2015-01-01

Abstract Objective: In the antibiotic era, purulent pericarditis is a rare entity. However, there are still reports of cases of the disease, which is associated with high mortality, and most such cases are attributed to delayed diagnosis. Approximately 40-50% of all cases of purulent pericarditis are caused by Gram-positive bacteria, Streptococcus pneumoniae in particular. Methods: We report four cases of pneumococcal pneumonia complicated by pericarditis, with different clinical features and levels of severity. Results: In three of the four cases, the main complication was cardiac tamponade. Microbiological screening (urinary antigen testing and pleural fluid culture) confirmed the diagnosis of severe pneumococcal pneumonia complicated by purulent pericarditis. Conclusions: In cases of pneumococcal pneumonia complicated by pericarditis, early diagnosis is of paramount importance to avoid severe hemodynamic compromise. The complications of acute pericarditis appear early in the clinical course of the infection. The most serious complications are cardiac tamponade and its consequences. Antibiotic therapy combined with pericardiocentesis drastically reduces the mortality associated with purulent pericarditis. PMID:26398760

How Does Streptococcus pneumoniae Invade the Brain?

PubMed

Iovino, Federico; Seinen, Jolien; Henriques-Normark, Birgitta; van Dijl, Jan Maarten

2016-04-01

Streptococcus pneumoniae (the pneumococcus) is the major cause of bacterial meningitis. The mechanisms by which pneumococci from the bloodstream penetrate the blood-brain barrier to reach the brain are not fully understood. Receptor-mediated adhesion of the bacteria to the brain endothelium is considered a key event leading to meningitis development. The aim of this review is to discuss recent advances and perspectives related to the interactions of S. pneumoniae with the blood-brain barrier during the events leading to meningitis. Altogether, the available data suggest that, by precisely defining the pathways and ligands by which S. pneumoniae adheres to specific receptors, it may be possible to interfere with the respective mechanisms and develop strategies to prevent or even cure pneumococcal meningitis. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Naval Health Research Center Respiratory Disease Laboratory.

PubMed

Ryan, M; Gray, G; Hawksworth, A; Malasig, M; Hudspeth, M; Poddar, S

2000-07-01

Concern about emerging and reemerging respiratory pathogens prompted the development of a respiratory disease reference laboratory at the Naval Health Research Center. Professionals working in this laboratory have instituted population-based surveillance for pathogens that affect military trainees and responded to threats of increased respiratory disease among high-risk military groups. Capabilities of this laboratory that are unique within the Department of Defense include adenovirus testing by viral shell culture and microneutralization serotyping, influenza culture and hemagglutination inhibition serotyping, and other special testing for Streptococcus pneumoniae, Streptococcus pyogenes, Mycoplasma pneumonia, and Chlamydia pneumoniae. Projected capabilities of this laboratory include more advanced testing for these pathogens and testing for other emerging pathogens, including Bordetella pertussis, Legionella pneumoniae, and Haemophilus influenzae type B. Such capabilities make the laboratory a valuable resource for military public health.

Draft Genome Sequences of Clinical Isolates of Serotype 6E Streptococcus pneumoniae from Five Asian Countries.

PubMed

Park, In Ho; Baek, Jin Yang; Song, Jae-Hoon; Ko, Kwan Soo; Kim, Kyung-Hyo

2017-03-09

Although serotype 6E Streptococcus pneumoniae consistently expresses capsules of either vaccine-serotype 6A or 6B, certain genetic variants of serotype 6E may evade vaccine induced immunity. Thus, draft genome sequences from five clinical isolates of serotype 6E from each of five different Asian countries have been generated to provide insight into the genomic diversity in serotype 6E strains. Copyright © 2017 Park et al.

Diagnosis of Streptococcus pneumoniae and Haemophilus influenzae type b meningitis by identifying DNA from cerebrospinal fluid-impregnated filter paper strips.

PubMed

Peltola, Heikki; Roine, Irmeli; Leinonen, Maija; Kuisma, Leena; Mata, Antonio González; Arbo, Antonio; Goyo, José; Saukkoriipi, Annika

2010-02-01

Bacterial meningitis remains often etiologically unconfirmed, especially in resource-poor settings. We tested the potential of real-time polymerase chain reaction to identify Streptococcus pneumoniae (Pnc) and Haemophilus influenzae type b (Hib) from cerebrospinal fluid impregnated on filter paper strips. Pnc and Hib genome equivalents were blindly quantified by polymerase chain reaction from 129 liquid cerebrospinal fluid (CSF) samples-the standard-and strips stored at room temperature for months. Genome counts were compared by simple regression. The strips showed a sensitivity and specificity of 92% and 99% for Pnc, and of 70% and 100% for Hib, respectively. The positive and negative predictive values were 94% and 97% for Pnc, and 100% and 89% for Hib, respectively. For Pnc, the positive and negative likelihood ratio was 92 and 0.08, and the overall accuracy 98%, whereas for Hib they were 70 and 0.30, and 91%, respectively. Genome counting showed good correlation between the filter paper and liquid CSF samples, r(2) being 0.87 for Pnc and 0.68 for Hib (P < 0.0001 for both). Although not replacing bacterial culture, filter paper strips offer an easy way to collect and store CSF samples for later bacteriology. They can also be transported in standard envelops by regular mail.

Streptococcus pneumoniae Is Desiccation Tolerant and Infectious upon Rehydration

PubMed Central

Walsh, Rebecca L.; Camilli, Andrew

2011-01-01

ABSTRACT Streptococcus pneumoniae (pneumococcus) is a frequent colonizer of the nasopharynx and one of the leading causative agents of otitis media, pneumonia, and meningitis. The current literature asserts that S. pneumoniae is transmitted person to person via respiratory droplets; however, environmental surfaces (fomites) have been linked to the spread of other respiratory pathogens. Desiccation tolerance has been to shown to be essential for long-term survival on dry surfaces. This study investigated the survival and infectivity of S. pneumoniae following desiccation under ambient conditions. We recovered viable bacteria after all desiccation periods tested, ranging from 1 h to 4 weeks. Experiments conducted under nutrient limitation indicate that desiccation is a condition separate from starvation. Desiccation of an acapsular mutant and 15 different clinical isolates shows that S. pneumoniae desiccation tolerance is independent of the polysaccharide capsule and is a species-wide phenomenon, respectively. Experiments demonstrating that nondesiccated and desiccated S. pneumoniae strains colonize the nasopharynx at comparable levels, combined with their ability to survive long-term desiccation, suggest that fomites may serve as alternate sources of pneumococcal infection. PMID:21610120

Smoke Exposure Exacerbates an Ethanol-Induced Defect in Mucociliary Clearance of Streptococcus pneumoniae

PubMed Central

Vander Top, Elizabeth A.; Wyatt, Todd A.; Gentry-Nielsen, Martha J.

2005-01-01

Background Alcoholics and smokers are particularly susceptible to pulmonary infections caused by Streptococcus pneumoniae, the pneumococcus. Infection begins when pneumococci colonizing the nasopharynx are aspirated into the lower respiratory tract. The major host defense against this movement is the mucociliary clearance apparatus. Both cigarette smoke and ethanol (EtOH) exposure alter ciliary beating and protein kinase activity in the respiratory mucosa in vitro, but their effects on bacterial clearance in the intact animal have not been determined. Methods Male Sprague-Dawley rats were exposed twice daily for 12 weeks to either the smoke generated from 30 cigarettes (smoke-exposed) or room air (sham-exposed). For the last five weeks of smoke exposure, the rats were fed Lieber-DeCarli liquid diets containing 0%, 16%, 26% or 36% EtOH calories. The rats then were infected intranasally with S. pneumoniae, and movement of the organisms into the lower respiratory tract was quantified by plate counts of the trachea and lungs four hours later. Ciliary beat frequency (CBF) analysis was performed on tracheal ring explants from each animal before and after stimulation with the β-agonist isoproterenol, and tracheal epithelial cell protein kinase C (PKC) activity was measured. Results Ingestion of any of the EtOH-containing diets resulted in a dose-dependent increase in movement of S. pneumoniae into the rats’ lungs. This EtOH-induced defect was augmented further by concurrent smoke exposure, although smoke exposure alone had little effect on S. pneumoniae movement. Smoke, but not EtOH exposure, activated tracheal epithelial cell PKC. Increased movement of organisms into lungs correlated with a decrease in CBF, and loss of the ciliary response to isoproterenol. Conclusion EtOH ingestion in our model facilitates movement of S. pneumoniae into rats’ lungs, a phenomenon exacerbated by concurrent smoke exposure. Furthermore, the organism’s movement into the lungs correlated with a blunting of the rats’ ciliary response to an established stimulus. Defects in mucociliary clearance thus may be one cause of the increased risk of pneumococcal infections in people who abuse alcohol, particularly if they also smoke. PMID:15897734

Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses

PubMed Central

McConnell, Kevin W.; McDunn, Jonathan E.; Clark, Andrew T.; Dunne, W. Michael; Dixon, David J.; Turnbull, Isaiah R.; DiPasco, Peter J.; Osberghaus, William F.; Sherman, Benjamin; Martin, James R.; Walter, Michael J.; Cobb, J. Perren; Buchman, Timothy G.; Hotchkiss, Richard S.; Coopersmith, Craig M.

2009-01-01

Objective Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, treatment involves only non-specific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar following disparate infections with similar mortalities. Design Prospective, randomized controlled study. Setting Animal laboratory in a university medical center. Interventions Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple timepoints. Measurements and Main Results The host response was dependent upon the causative organism as well as kinetics of mortality, but the pro- and anti- inflammatory response was independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of 5 distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary MIP-2 and IL-10 with progression of infection while elevated plasma TNFsr2 and MCP-1 were indicative of fulminant disease with >90% mortality within 48 hours. Conclusions Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a potential therapeutic approach in the treatment of sepsis. PMID:19770740

Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses.

PubMed

McConnell, Kevin W; McDunn, Jonathan E; Clark, Andrew T; Dunne, W Michael; Dixon, David J; Turnbull, Isaiah R; Dipasco, Peter J; Osberghaus, William F; Sherman, Benjamin; Martin, James R; Walter, Michael J; Cobb, J Perren; Buchman, Timothy G; Hotchkiss, Richard S; Coopersmith, Craig M

2010-01-01

Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, then treatment involves only nonspecific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar after disparate infections with similar mortalities. Prospective, randomized controlled study. Animal laboratory in a university medical center. Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple time points. The host response was dependent on the causative organism as well as kinetics of mortality, but the pro-inflammatory and anti-inflammatory responses were independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of five distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary macrophage inflammatory peptide-2 and interleukin-10 with progression of infection, whereas elevated plasma tumor necrosis factor sr2 and macrophage chemotactic peptide-1 were indicative of fulminant disease with >90% mortality within 48 hrs. Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a potential therapeutic approach in the treatment of sepsis.

Hepatic Concentration and Distribution of Coenzyme A and Carnitine during a Streptococcus pneumoniae Infection in the Rat: Possible Implications on Fatty Acid Metabolism and Ketogenesis

DTIC Science & Technology

1981-01-09

subcellular distribution of carnitine and coenzyme A (CoA). Compared to fasted control ILJ rats, fasted-infected rats have a decreased ketogenic capacity...decreased ketogenic capacity that is associated with an accumulation of total hepatic carnitine and a decrease in total hepatic coenzyme A. The...cholesterol. IiA .Ii INTRODUCTION Rats infected with Streptococcus pneumoniae have a decreased hep-tic ketogenic capacity which is associated with an

Respiratory Diseases among U.S. Military Personnel: Countering Emerging Threats

PubMed Central

Callahan, Johnny D.; Hawksworth, Anthony W.; Fisher, Carol A.; Gaydos, Joel C.

1999-01-01

Emerging respiratory disease agents, increased antibiotic resistance, and the loss of effective vaccines threaten to increase the incidence of respiratory disease in military personnel. We examine six respiratory pathogens (adenoviruses, influenza viruses, Streptococcus pneumoniae, Streptococcus pyogenes, Mycoplasma pneumoniae, and Bordetella pertussis) and review the impact of the diseases they cause, past efforts to control these diseases in U.S. military personnel, as well as current treatment and surveillance strategies, limitations in diagnostic testing, and vaccine needs. PMID:10341174

Structure of the choline-binding domain of Spr1274 in Streptococcus pneumoniae.

PubMed

Zhang, Zhenyi; Li, Wenzhe; Frolet, Cecile; Bao, Rui; di Guilmi, Anne Marie; Vernet, Thierry; Chen, Yuxing

2009-08-01

Spr1274 is a putative choline-binding protein that is bound to the cell wall of Streptococcus pneumoniae through noncovalent interactions with the choline moieties of teichoic and lipoteichoic acids. Its function is still unknown. The crystal structure of the choline-binding domain of Spr1274 (residues 44-129) was solved at 2.38 A resolution with three molecules in the asymmetric unit. It may provide a structural basis for functional analysis of choline-binding proteins.

Platelet activation is a key event in the pathogenesis of streptococcal infections.

PubMed

Jia, Ming; Xiong, Yuling; Lu, Hua; Li, Ruqing; Wang, Tiantian; Ye, Yanyao; Song, Min; Li, Bing; Jiang, Tianlun; Zhao, Shuming

2015-06-01

Diverse Streptococcus species including Streptococcus Pneumoniae, Sanguis, Gordonii, Mitis and Mutans cause life-threatening conditions including pneumonia, bacteremia and meningitis. These diseases bear a high morbidity and mortality and for this reason, understanding the key events in the pathogenesis of these infections have a great significance in their prevention and/or treatment. Here, we describe as how the activation of the platelets and their affinity to bind to bacterial proteins act as early key events in the pathogenesis of Streptococcal infections.

Development of approaches to a third-generation carbohydrate-conjugate vaccine against Streptococcus pneumoniae: the search for optimal oligosaccharide ligands

NASA Astrophysics Data System (ADS)

Gening, M. L.; Kurbatova, E. A.; Tsvetkov, Yu E.; Nifantiev, N. E.

2015-11-01

The review addresses the application of synthetic oligosaccharides related to fragments of capsular polysaccharides from different serotypes of the bacterium Streptococcus pneumoniae for the design of third-generation pneumococcal conjugate vaccines. Special focus is given to characteristic features of the chemical structures of oligosaccharides required for the induction of the protective immune response when using synthetic glycoconjugate vaccines based on oligosaccharide ligands and carrier proteins. The bibliography includes 101 references.

Eradication of Streptococcus pneumoniae in the Nasopharyngeal Flora of Children with Acute Otitis Media after Amoxicillin-Clavulanate Therapy

PubMed Central

Brook, Itzhak; Gober, Alan E.

2004-01-01

Nasopharyngeal cultures were obtained from 60 children with acute otitis media before and after treatment with either 45 or 90 mg of amoxicillin (given as amoxicillin-clavulanate) per kg of body weight per day for 10 days. The number of Streptococcus pneumoniae isolates in the 45-mg/kg group was reduced from 12 to 6 and was reduced from 14 to 1 (P = 0.0261) in the 90-mg/kg group. PMID:15047558

Protective Role of the Capsule and Impact of Serotype 4 Switching on Streptococcus mitis

PubMed Central

Rukke, Håkon V.; Kalluru, Raja Sab; Repnik, Urska; Gerlini, Alice; José, Ricardo J.; Periselneris, Jimstan; Marshall, Helina; Griffiths, Gareth; Oggioni, Marco Rinaldo; Brown, Jeremy S.

2014-01-01

The polysaccharide capsule surrounding Streptococcus pneumoniae is essential for virulence. Recently, Streptococcus mitis, a human commensal and a close relative of S. pneumoniae, was also shown to have a capsule. In this study, the S. mitis type strain switched capsule by acquisition of the serotype 4 capsule locus of S. pneumoniae TIGR4, following induction of competence for natural transformation. Comparison of the wild type with the capsule-switching mutant and with a capsule deletion mutant showed that the capsule protected S. mitis against phagocytosis by RAW 264.7 macrophages. This effect was enhanced in the S. mitis strain expressing the S. pneumoniae capsule, which showed, in addition, increased resistance against early clearance in a mouse model of lung infection. Expression of both capsules also favored survival in human blood, and the effect was again more pronounced for the capsule-switching mutant. S. mitis survival in horse blood or in a mouse model of bacteremia was not significantly different between the wild type and the mutant strains. In all models, S. pneumoniae TIGR4 showed higher rates of survival than the S. mitis type strain or the capsule-switching mutant, except in the lung model, in which significant differences between S. pneumoniae TIGR4 and the capsule-switching mutant were not observed. Thus, we identified conditions that showed a protective function for the capsule in S. mitis. Under such conditions, S. mitis resistance to clearance could be enhanced by capsule switching to serotype 4, but it was enhanced to levels lower than those for the virulent strain S. pneumoniae TIGR4. PMID:24958712

Antimicrobial Susceptibilities of 1,684 Streptococcus pneumoniae and 2,039 Streptococcus pyogenes Isolates and Their Ecological Relationships: Results of a 1-Year (1998–1999) Multicenter Surveillance Study in Spain

PubMed Central

Pérez-Trallero, E.; Fernández-Mazarrasa, C.; García-Rey, C.; Bouza, E.; Aguilar, L.; García-de-Lomas, J.; Baquero, F.

2001-01-01

A nationwide multicenter susceptibility surveillance study which included 1,684 Streptococcus pneumoniae and 2,039 S. pyogenes isolates was carried out over 1 year in order to assess the current resistance patterns for the two most important gram-positive microorganisms responsible for community-acquired infections in Spain. Susceptibility testing was done by a broth microdilution method according to National Committee for Clinical Laboratory Standards M100-S10 interpretative criteria. For S. pneumoniae, the prevalences of highly resistant strains were 5% for amoxicillin and amoxicillin-clavulanic acid; 7% for cefotaxime; 22% for penicillin; 31% for cefuroxime; 35% for erythromycin, clarithromycin, and azithromycin; and 42% for cefaclor. For S. pyogenes, the prevalence of erythromycin resistance was 20%. Efflux was encountered in 90% of S. pyogenes and 5% of S. pneumoniae isolates that exhibited erythromycin resistance. Erythromycin resistance was associated with clarithromycin and azithromycin in both species, regardless of phenotype. Despite the different nature of the mechanisms of resistance, a positive correlation (r = 0.612) between the two species in the prevalence of erythromycin resistance was found in site-by-site comparisons, suggesting some kind of link with antibiotic consumption. Regarding ciprofloxacin, the MIC was ≥4 μg/ml for 7% of S. pneumoniae and 3.5% of S. pyogenes isolates. Ciprofloxacin resistance (MIC, ≥4 μg/ml) was significantly (P < 0.05) associated with macrolide resistance in both S. pyogenes and S. pneumoniae and with penicillin nonsusceptibility in S. pneumoniae. PMID:11709305

A Community-acquired Lung Abscess Attributable to Streptococcus pneumoniae which Extended Directly into the Chest Wall

PubMed Central

Ko, Yuki; Tobino, Kazunori; Yasuda, Yuichiro; Sueyasu, Takuto; Nishizawa, Saori; Yoshimine, Kouhei; Munechika, Miyuki; Asaji, Mina; Yamaji, Yoshikazu; Tsuruno, Kosuke; Miyajima, Hiroyuki; Mukasa, Yosuke; Ebi, Noriyuki

2017-01-01

We herein report the case of 75-year-old Japanese female with a community-acquired lung abscess attributable to Streptococcus pneumoniae (S. penumoniae) which extended into the chest wall. The patient was admitted to our hospital with a painful mass on the left anterior chest wall. A contrast-enhanced chest computed tomography scan showed a lung abscess in the left upper lobe which extended into the chest wall. Surgical debridement of the chest wall abscess and percutaneous transthoracic tube drainage of the lung abscess were performed. A culture of the drainage specimen yielded S. pneumoniae. The patient showed a remarkable improvement after the initiation of intravenous antibiotic therapy. PMID:28049987

A Community-acquired Lung Abscess Attributable to Streptococcus pneumoniae which Extended Directly into the Chest Wall.

PubMed

Ko, Yuki; Tobino, Kazunori; Yasuda, Yuichiro; Sueyasu, Takuto; Nishizawa, Saori; Yoshimine, Kouhei; Munechika, Miyuki; Asaji, Mina; Yamaji, Yoshikazu; Tsuruno, Kosuke; Miyajima, Hiroyuki; Mukasa, Yosuke; Ebi, Noriyuki

We herein report the case of 75-year-old Japanese female with a community-acquired lung abscess attributable to Streptococcus pneumoniae (S. penumoniae) which extended into the chest wall. The patient was admitted to our hospital with a painful mass on the left anterior chest wall. A contrast-enhanced chest computed tomography scan showed a lung abscess in the left upper lobe which extended into the chest wall. Surgical debridement of the chest wall abscess and percutaneous transthoracic tube drainage of the lung abscess were performed. A culture of the drainage specimen yielded S. pneumoniae. The patient showed a remarkable improvement after the initiation of intravenous antibiotic therapy.

Interruption of capsule production in Streptococcus pneumonia serotype 3 by insertion of transposon Tn916.

PubMed Central

Watson, D A; Musher, D M

1990-01-01

Transposon Tn916 mutagenesis was used to produce mutant strains of Streptococcus pneumoniae serotype 3 that lacked only a polysaccharide capsule. Southern blotting, DNA-DNA hybridization, and immunochemical analyses demonstrated that the presence of a single copy of Tn916 was sufficient to produce unencapsulation. The 50% lethal dose for such mutants was greater than 5 x 10(7) CFU, as opposed to a 50% lethal dose of 1 CFU for wild-type strains. These experiments outline an effective method for targeting genes in S. pneumoniae by transposon interruption and provide molecular evidence to support the longstanding hypothesis that the capsule is the principal virulence factor in this pathogen. Images PMID:2167295

Serotype Distribution and Antimicrobial Resistance of Streptococcus pneumoniae Isolates from Pediatric Patients in Singapore

PubMed Central

Soh, Shirlena Wee-Ling; Poh, Chit Laa; Lin, Raymond V. Tzer Pin

2000-01-01

One hundred eighty Streptococcus pneumoniae strains isolated from children at a pediatric hospital in Singapore from 1997 to 1999 were serotyped and their antimicrobial susceptibility patterns were determined. Sixty-three percent of the isolates were resistant to penicillin. Significantly large numbers of the strains investigated were resistant to trimethoprim-sulfamethoxazole (87.8%), tetracycline (71.7%), erythromycin (67.8%), and chloramphenicol (40%). Penicillin and multidrug resistance was mostly associated with the frequently isolated S. pneumoniae isolates of serotypes (serotypes 19F, 23F, 6B, and 14). Isolates of serotype 19F, the serotype most commonly encountered in Singapore (41.1%), had the highest prevalence of penicillin (78.4%) and multidrug resistance (94.6%). Most of the invasive S. pneumoniae isolates (8 of 17; 47.1%) were of serotype 14. PMID:10898701

Insights into the Evolutionary Relationships of LytA Autolysin and Ply Pneumolysin-Like Genes in Streptococcus pneumoniae and Related Streptococci.

PubMed

Morales, María; Martín-Galiano, Antonio J; Domenech, Mirian; García, Ernesto

2015-09-08

Streptococcus pneumoniae (pneumococcus) is a major human pathogen. The main pneumococcal autolysin LytA and the pneumolysin Ply are two of the bacterium's most important virulence factors. The lytA- and ply-related genes are also found in other streptococci of the Mitis group (SMG). The precise characteristics of the lytA-related-but not the ply-related-genes of SMG and their prophages have been previously described. A search of the more than 400 SMG genomic sequences available in public databases (ca. 300 for S. pneumoniae), showed Streptococcus pseudopneumoniae IS7493 to harbor four ply-related genes, two of which (plyA and plyB) have 98% identical nucleotides. The plyA homolog of S. pseudopneumoniae is conserved in all S. pneumoniae strains, and seems to be included in a pathogenicity island together with the lytA gene. However, only nonencapsulated S. pneumoniae strains possess a plyB gene, which is part of an integrative and conjugative element. Notably, the existence of a bacterial lytA-related gene in a genome is linked to the presence of plyA and vice versa. The present analysis also shows there are eight main types of plyA-lytA genomic islands. A possible stepwise scenario for the evolution of the plyA-lytA island in S. pneumoniae is proposed. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Screening of antibacterial effects of anise essential oil alone and in combination with conventional antibiotics against Streptococcus pneumoniae clinical isolates.

PubMed

Gradinaru, Adina Catinca; Miron, Anca; Trifan, Adriana; Spac, A; Brebu, M; Aprotosoaie, Ana Clara

2014-01-01

This study aimed to investigate the effects of anise essential oil alone and in combination with conventional antibiotics (amoxicillin, ciprofloxacin) against Streptococcus pneumoniae clinical isolates. MATERIAL AND METHODs: Anise essential oil (AEO) was isolated by hydrodistillation from dried powdered fruits. Its chemical composition was investigated by GC-MS and GC-FID. Broth dilution assay was used to evaluate the antibacterial effects of anise essential oil. The interactions with antibiotics were studied by the checkerboard assay. Trans-anethole (90.18%) was identified as major constituent in anise essential oil. Almost all combinations AEO-amoxicillin and AEO-ciprofloxacin showed indifferent interactions (1 < FIC index < or = 2). Positive interactions (addition and weak synergism) were found only for four combinations AEO-amoxicillin (FIC index = 1,0.62, 0.75 and 0.5) and one combination AEO-ciprofloxacin (FIC index = 0.62). Herbal products containing anise essential oil may be used as expectorants in combination with amoxicillin or ciprofloxacin in Streptococcus pneumoniae infections without diminishing antibiotic efficacy.

In vitro expression of Streptococcus pneumoniae ply gene in human monocytes and pneumocytes.

PubMed

Hu, Da-Kang; Liu, Yang; Li, Xiang-Yang; Qu, Ying

2015-05-07

Streptococcus pneumoniae is one major cause of pneumonia in human and contains various virulence factors that contribute to pathogenesis of pneumococcal disease. This study investigated the role of pneumolysin, Ply, in facilitating S. pneumoniae invasion into the host blood stream. S. pneumoniae strains were isolated from clinical blood and sputum samples and confirmed by PCR. Expression of ply gene was assessed by infecting human monocytes and pneumocytes. A total of 23 strains of S. pneumoniae isolated from blood (n = 11) and sputum (n = 12) along with S. pneumoniae ATCC49619 were used to infect human monocyte (THP-1) and Type II pneumocyte (A549) cell lines. All clinical strains of S. pneumoniae showed higher expression of ply mRNA than the American Type Culture Collection (ATCC) strain. Among the clinical strains, blood isolates showed higher expression of ply genes than sputum isolates, i.e., 2(1.5)- to 2(1.6)-folds in THP-1 and 2(0.4)- to 2(4.9)-folds in A549 cell lines. The data from the current study demonstrated that ply gene of blood- and sputum-derived S. pneumoniae is differentially expressed in two different cell lines. Under survival pressure, ply is highly expressed in these two cell lines for blood-derived S. pneumoniae, indicating that ply gene may facilitate S. pneumoniae invasion into the host blood system.

Study on the excision and integration mediated by class 1 integron in Streptococcus pneumoniae.

PubMed

Lin, Qun; Xu, Pusheng; Li, Jiaowu; Huang, Jinhua; Chen, Yin; Deng, Shuhuan

2017-10-01

As a novel antibiotic resistance mobile element, integron was recognized as a primary source of antibiotic genes among Gram-positive organisms for its excision and integration of exogenous genes. In this study, Streptococcus pneumoniae was subjected to investigate the excision and integration of class 1 integron with eight different plasmids. As the results indicated, excision in both att site and gene cassettes were successfully observed, which was further confirmed by integration assays and PCR amplification. The observation of class 1 integron mediated excision and integration of various exogenous antibiotics resistance genes may raise the attention of integrons as novel antibiotic resistance determinant in Gram-positive bacteria, especially in Streptococcus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pediatric Complicated Pneumonia Caused by Streptococcus pneumoniae Serotype 3 in 13-Valent Pneumococcal Conjugate Vaccinees, Portugal, 2010-2015.

PubMed

Silva-Costa, Catarina; Brito, Maria João; Pinho, Marcos D; Friães, Ana; Aguiar, Sandra I; Ramirez, M; Melo-Cristino, Jose

2018-07-01

Despite use of 7-valent pneumococcal conjugate vaccine, incidence of pleural effusion and empyema (pediatric complicated pneumococcal pneumonia [PCPP]) is reportedly increasing globally. We cultured and performed PCR on 152 pleural fluid samples recovered from pediatric patients in Portugal during 2010-2015 to identify and serotype Streptococcus pneumoniae. We identified only 17 cases by culture, but molecular methods identified S. pneumoniae in 68% (92/135) of culture-negative samples. The most frequent serotypes were 3, 1, and 19A, together accounting for 62% (68/109) of cases. Nineteen cases attributable to 13-valent pneumococcal conjugate vaccine (PCV13) serotypes (mostly serotype 3) were detected among 22 children age-appropriately vaccinated with PCV13. The dominance of the additional serotypes included in PCV13 among PCPP cases in Portugal continues, even with PCV13 available on the private market (without reimbursement) since 2010 and with average annual coverage of 61% among age-eligible children. Our data suggest reduced effectiveness of PCV13 against serotype 3 PCPP.

Effect of decreased BCAA synthesis through disruption of ilvC gene on the virulence of Streptococcus pneumoniae.

PubMed

Kim, Gyu-Lee; Lee, Seungyeop; Luong, Truc Thanh; Nguyen, Cuong Thach; Park, Sang-Sang; Pyo, Suhkneung; Rhee, Dong-Kwon

2017-08-01

Streptococcus pneumoniae (pneumococcus) is responsible for significant morbidity and mortality worldwide. It causes a variety of life-threatening infections such as pneumonia, bacteremia, and meningitis. In bacterial physiology, the metabolic pathway of branched-chain amino acids (BCAAs) plays an important role in virulence. Nonetheless, the function of IlvC, one of the enzymes involved in the biosynthesis of BCAAs, in S. pneumoniae remains unclear. Here, we demonstrated that downregulation of BCAA biosynthesis by ilvC ablation can diminish BCAA concentration and expression of pneumolysin (Ply) and LytA, and subsequently attenuate virulence. Infection with an ilvC mutant showed significantly reduced mortality and colonization in comparison with strain D39 (serotype 2, wild type), suggesting that ilvC can potentiate S. pneumoniae virulence due to adequate BCAA synthesis. Taken together, these results suggest that the function of ilvC in BCAA synthesis is essential for virulence factor and could play an important role in the pathogenesis of respiratory infections.

Global antibiotic resistance in Streptococcus pneumoniae.

PubMed

Adam, Dieter

2002-07-01

The last two decades of the 20th century were marked by an increasing resistance rate among several bacteria. Threat of resistance is present in Staphylococcus spp., Enterococcus spp., Pseudomonas spp. and Enterobacteriaceae, which are the major pathogens in nosocomial infections. In the community, too, increasing resistance can be observed and is attributed mainly (but not exclusively) to Streptococcus pneumoniae and Haemophilus influenzae. To scrutinize this trend, resistance surveillance in the community was established about 10 years ago. One of the multinational, longitudinal surveillance programmes in place is the Alexander Project, which was established in 1992 to monitor the susceptibility of the major community-acquired lower respiratory tract pathogens to a range of antibacterial drugs. The Alexander Project has revealed a tendency towards increasing resistance of S. pneumoniae to penicillin and macrolide therapy. Within Europe, the prevalence of penicillin resistance among S. pneumoniae isolates is particularly high in France and Spain. Macrolide resistance in S. pneumoniae is also a growing problem in European countries such as France, Spain, Belgium and Italy, where the extent of macrolide resistance in S. pneumoniae now exceeds that of penicillin resistance.

An evolutionary model to predict the frequency of antibiotic resistance under seasonal antibiotic use, and an application to Streptococcus pneumoniae

PubMed Central

Lehtinen, Sonja; Fraser, Christophe

2017-01-01

The frequency of resistance to antibiotics in Streptococcus pneumoniae has been stable over recent decades. For example, penicillin non-susceptibility in Europe has fluctuated between 12% and 16% without any major time trend. In spite of long-term stability, resistance fluctuates over short time scales, presumably in part due to seasonal fluctuations in antibiotic prescriptions. Here, we develop a model that describes the evolution of antibiotic resistance under selection by multiple antibiotics prescribed at seasonally changing rates. This model was inspired by, and fitted to, published data on monthly antibiotics prescriptions and frequency of resistance in two communities in Israel over 5 years. Seasonal fluctuations in antibiotic usage translate into small fluctuations of the frequency of resistance around the average value. We describe these dynamics using a perturbation approach that encapsulates all ecological and evolutionary forces into a generic model, whose parameters quantify a force stabilizing the frequency of resistance around the equilibrium and the sensitivity of the population to antibiotic selection. Fitting the model to the data revealed a strong stabilizing force, typically two to five times stronger than direct selection due to antibiotics. The strong stabilizing force explains that resistance fluctuates in phase with usage, as antibiotic selection alone would result in resistance fluctuating behind usage with a lag of three months when antibiotic use is seasonal. While most antibiotics selected for increased resistance, intriguingly, cephalosporins selected for decreased resistance to penicillins and macrolides, an effect consistent in the two communities. One extra monthly prescription of cephalosporins per 1000 children decreased the frequency of penicillin-resistant strains by 1.7%. This model emerges under minimal assumptions, quantifies the forces acting on resistance and explains up to 43% of the temporal variation in resistance. PMID:28566489

Antibiotic susceptibility in Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes in Pakistan: a review of results from the Survey of Antibiotic Resistance (SOAR) 2002-15.

PubMed

Zafar, A; Hasan, R; Nizamuddin, S; Mahmood, N; Mukhtar, S; Ali, F; Morrissey, I; Barker, K; Torumkuney, D

2016-05-01

To investigate changes in the antibiotic susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes from the Survey of Antibiotic Resistance (SOAR) in community-acquired respiratory tract infections (CA-RTIs) between 2002 and 2015 in Pakistan. This is a review based on previously published studies from 2002-03, 2004-06 and 2007-09 and also new data from 2014-15. Susceptibility was determined by Etest(®) or disc diffusion according to CLSI and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. A total of 706 isolates from CA-RTIs comprising 381 S. pneumoniae, 230 H. influenzae and 95 S. pyogenes were collected between 2002 and 2015 and tested against a range of antibiotics. Antibiotic resistance in S. pneumoniae rose steeply from 2002 to 2009, with isolates non-susceptible to penicillin and macrolides increasing from 10% to 34.1% and from 13%-14% to 29.7%, respectively. Susceptibility to amoxicillin/clavulanic acid (and by inference amoxicillin) remained between 99.4% and 100% from 2002 to 2015. Over the years, the prevalence of susceptibility to cefuroxime was 98%-100% among S. pneumoniae. Resistance in S. pneumoniae to some older antibiotics between 2007 and 2009 was high (86.8% for trimethoprim/sulfamethoxazole and 57.2% for tetracycline). Between 2002 and 2015, ampicillin resistance (β-lactamase-positive strains) among H. influenzae has remained low (between 2.6% and 3.2%) and almost unchanged over the years (H. influenzae was not tested during 2004-06). For S. pyogenes isolates, macrolide resistance reached 22%; however, susceptibility to penicillin, amoxicillin/clavulanic acid and cefuroxime remained stable at 100%. In S. pneumoniae from Pakistan, there has been a clear reduction in susceptibility to key antibiotics since 2002, but not to amoxicillin/clavulanic acid (amoxicillin) or cefuroxime. However, susceptibility in H. influenzae has remained stable. Local antibiotic susceptibility/resistance data are essential to support informed prescribing for CA-RTIs and other infections. © The Author 2016. 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.

[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.

Benchmarking Various Green Fluorescent Protein Variants in Bacillus subtilis, Streptococcus pneumoniae, and Lactococcus lactis for Live Cell Imaging

PubMed Central

Overkamp, Wout; Beilharz, Katrin; Detert Oude Weme, Ruud; Solopova, Ana; Karsens, Harma; Kovács, Ákos T.; Kok, Jan

2013-01-01

Green fluorescent protein (GFP) offers efficient ways of visualizing promoter activity and protein localization in vivo, and many different variants are currently available to study bacterial cell biology. Which of these variants is best suited for a certain bacterial strain, goal, or experimental condition is not clear. Here, we have designed and constructed two “superfolder” GFPs with codon adaptation specifically for Bacillus subtilis and Streptococcus pneumoniae and have benchmarked them against five other previously available variants of GFP in B. subtilis, S. pneumoniae, and Lactococcus lactis, using promoter-gfp fusions. Surprisingly, the best-performing GFP under our experimental conditions in B. subtilis was the one codon optimized for S. pneumoniae and vice versa. The data and tools described in this study will be useful for cell biology studies in low-GC-rich Gram-positive bacteria. PMID:23956387

Crystal structure of Streptococcus pneumoniae pneumolysin provides key insights into early steps of pore formation

PubMed Central

Lawrence, Sara L.; Feil, Susanne C.; Morton, Craig J.; Farrand, Allison J.; Mulhern, Terrence D.; Gorman, Michael A.; Wade, Kristin R.; Tweten, Rodney K.; Parker, Michael W.

2015-01-01

Pore-forming proteins are weapons often used by bacterial pathogens to breach the membrane barrier of target cells. Despite their critical role in infection important structural aspects of the mechanism of how these proteins assemble into pores remain unknown. Streptococcus pneumoniae is the world’s leading cause of pneumonia, meningitis, bacteremia and otitis media. Pneumolysin (PLY) is a major virulence factor of S. pneumoniae and a target for both small molecule drug development and vaccines. PLY is a member of the cholesterol-dependent cytolysins (CDCs), a family of pore-forming toxins that form gigantic pores in cell membranes. Here we present the structure of PLY determined by X-ray crystallography and, in solution, by small-angle X-ray scattering. The crystal structure reveals PLY assembles as a linear oligomer that provides key structural insights into the poorly understood early monomer-monomer interactions of CDCs at the membrane surface. PMID:26403197

Detection of Streptococcus pneumoniae and Haemophilus influenzae Type B by Real-Time PCR from Dried Blood Spot Samples among Children with Pneumonia: A Useful Approach for Developing Countries

PubMed Central

Selva, Laura; Benmessaoud, Rachid; Lanaspa, Miguel; Jroundi, Imane; Moraleda, Cinta; Acacio, Sozinho; Iñigo, Melania; Bastiani, Alien; Monsonis, Manuel; Pallares, Roman; Bassat, Quique; Muñoz-Almagro, Carmen

2013-01-01

Background Dried blood spot (DBS) is a reliable blood collection method for storing samples at room temperature and easily transporting them. We have previously validated a Real-Time PCR for detection of Streptococcus pneumoniae in DBS. The objective of this study was to apply this methodology for the diagnosis of S. pneumoniae and Haemophilus influenzae b (Hib) in DBS samples of children with pneumonia admitted to two hospitals in Mozambique and Morocco. Methods Ply and wzg genes of S. pneumoniae and bexA gene of Hib, were used as targets of Real-Time PCR. 329 DBS samples of children hospitalized with clinical diagnosis of pneumonia were tested. Results Real-Time PCR in DBS allowed for a significant increase in microbiological diagnosis of S. pneumoniae and Hib. When performing blood bacterial culture, only ten isolates of S. pneumoniae and none of Hib were detected (3·0% positivity rate, IC95% 1·4-5·5%). Real-Time PCR from DBS samples increased the detection yield by 4x fold, as 30 S. pneumoniae and 11 Hib cases were detected (12·4% positivity rate, IC95% 9·0-16·5%; P<0·001). Conclusion Real-Time PCR applied in DBS may be a valuable tool for improving diagnosis and surveillance of pneumonia caused by S. pneumoniae or Hib in developing countries. PMID:24116190

Penicillin-binding protein 1A, 2B, and 2X alterations in Canadian isolates of penicillin-resistant Streptococcus pneumoniae.

PubMed

Nichol, Kimberly A; Zhanel, George G; Hoban, Daryl J

2002-10-01

Alterations within the penicillin-binding domain of penicillin-binding protein (PBP) genes pbp1a, pbp2b, and pbp2x were determined for 15 Canadian isolates of Streptococcus pneumoniae. All penicillin-nonsusceptible S. pneumoniae isolates showed a variety of PBP 2X substitutions and contained a Thr445-Ala change after the PBP 2B SSN motif. Only isolates for which penicillin MICs were > or =0.5 micro g/ml had PBP 1A alterations near the STMK and SRN motifs. Sequence analysis revealed identical PBP 1A, PBP 2B, and PBP 2X substitution patterns among all isolates for which penicillin MICs were > or =1 micro g/ml.

Penicillin-Binding Protein 1A, 2B, and 2X Alterations in Canadian Isolates of Penicillin-Resistant Streptococcus pneumoniae

PubMed Central

Nichol, Kimberly A.; Zhanel, George G.; Hoban, Daryl J.

2002-01-01

Alterations within the penicillin-binding domain of penicillin-binding protein (PBP) genes pbp1a, pbp2b, and pbp2x were determined for 15 Canadian isolates of Streptococcus pneumoniae. All penicillin-nonsusceptible S. pneumoniae isolates showed a variety of PBP 2X substitutions and contained a Thr445-Ala change after the PBP 2B SSN motif. Only isolates for which penicillin MICs were ≥0.5 μg/ml had PBP 1A alterations near the STMK and SRN motifs. Sequence analysis revealed identical PBP 1A, PBP 2B, and PBP 2X substitution patterns among all isolates for which penicillin MICs were ≥1 μg/ml. PMID:12234855

The high vaginal swab in general practice: clinical correlates of possible pathogens.

PubMed

Dykhuizen, R S; Harvey, G; Gould, I M

1995-06-01

Clinical features, diagnosis and treatment of 286 women whose high vaginal swabs (HVS) submitted by their general practitioners showed pure, heavy growth of Staphylococcus aureus, beta haemolytic streptococci groups A, C or G, Streptococcus milleri, Streptococcus pneumoniae or Haemophilus influenzae were analysed. Women with group A, C and G streptococci frequently had clinical vulvovaginitis and although the numbers were too small for statistical confirmation, S. pneumoniae and H. influenzae appeared to cause clinical disease as well. The association of S. aureus or S. milleri with clinical vulvovaginitis was much less convincing. It seems relevant for laboratories to report sensitivities for group A, C and G streptococci. Further research is needed to determine the pathogenicity of S. pneumoniae and H. influenzae.

Quinupristin-Dalfopristin Resistance in Streptococcus pneumoniae: Novel L22 Ribosomal Protein Mutation in Two Clinical Isolates from the SENTRY Antimicrobial Surveillance Program

PubMed Central

Jones, Ronald N.; Farrell, David J.; Morrissey, Ian

2003-01-01

Resistance to quinupristin-dalfopristin (Q/D) among gram-positive cocci has been very uncommon. Two clinical isolates among 8,837 (0.02%) Streptococcus pneumoniae isolates were discovered in 2001 to 2002 with Q/D MICs of 4 μg/ml. Each had a 5-amino-acid tandem duplication (RTAHI) in the L22 ribosomal protein gene (rplV) preventing synergistic ribosomal binding of the streptogramin combination. Similar gene duplication has been reported in Q/D-resistant Staphylococcus aureus. PMID:12878545

Bacterial Co-infection in Hospitalized Children with Mycoplasma pneumoniae Pneumonia.

PubMed

Song, Qing; Xu, Bao-Ping; Shen, Kun-Ling

2016-10-08

To describe the frequency and impact of bacterial co-infections in children hospitalized with Mycoplasma pneumoniae pneumonia. Retrospective, descriptive study. Tertiary-care hospital in Beijing, China. 8612 children admitted to Beijing Childrens Hospital from June 2006 to June 2014. According to the testing results of etiology we divided the cases into pure M. pneumoniae infection group and mixed bacterial infection group. We analyzed clinical features, hospital expenses and differences between these two groups. 173 (2%) of included children had bacterial coinfection. 56.2% of bacterial pathogens were identified as Streptococcus pneumoniae. The most common bacterium causing co-infection in children with M. pneumoniae pneumonia was S. pneumoniae.

21 CFR 522.90a - Ampicillin trihydrate sterile suspension.

Code of Federal Regulations, 2010 CFR

2010-04-01

... tract infections due to E. coli, Pseudomonas spp., Proteus spp., Staphylococcus spp., and Streptococcus spp.; tonsillitis due to E. coli, Pseudomonas spp., Streptococcus spp., and Staphylococcus spp.... Treatment of bacterial enteritis (colibacillosis) caused by E. coli and bacterial pneumonia caused by...

21 CFR 522.90a - Ampicillin trihydrate sterile suspension.

Code of Federal Regulations, 2011 CFR

2011-04-01

... tract infections due to E. coli, Pseudomonas spp., Proteus spp., Staphylococcus spp., and Streptococcus spp.; tonsillitis due to E. coli, Pseudomonas spp., Streptococcus spp., and Staphylococcus spp.... Treatment of bacterial enteritis (colibacillosis) caused by E. coli and bacterial pneumonia caused by...

rpoB Gene Sequence-Based Identification of Aerobic Gram-Positive Cocci of the Genera Streptococcus, Enterococcus, Gemella, Abiotrophia, and Granulicatella

PubMed Central

Drancourt, Michel; Roux, Véronique; Fournier, Pierre-Edouard; Raoult, Didier

2004-01-01

We developed a new molecular tool based on rpoB gene (encoding the beta subunit of RNA polymerase) sequencing to identify streptococci. We first sequenced the complete rpoB gene for Streptococcus anginosus, S. equinus, and Abiotrophia defectiva. Sequences were aligned with these of S. pyogenes, S. agalactiae, and S. pneumoniae available in GenBank. Using an in-house analysis program (SVARAP), we identified a 740-bp variable region surrounded by conserved, 20-bp zones and, by using these conserved zones as PCR primer targets, we amplified and sequenced this variable region in an additional 30 Streptococcus, Enterococcus, Gemella, Granulicatella, and Abiotrophia species. This region exhibited 71.2 to 99.3% interspecies homology. We therefore applied our identification system by PCR amplification and sequencing to a collection of 102 streptococci and 60 bacterial isolates belonging to other genera. Amplicons were obtained in streptococci and Bacillus cereus, and sequencing allowed us to make a correct identification of streptococci. Molecular signatures were determined for the discrimination of closely related species within the S. pneumoniae-S. oralis-S. mitis group and the S. agalactiae-S. difficile group. These signatures allowed us to design a S. pneumoniae-specific PCR and sequencing primer pair. PMID:14766807

Pleural empyema and streptococcal toxic shock syndrome due to Streptococcus pyogenes in a healthy Spanish traveler in Japan.

PubMed

Sakai, Tetsuya; Taniyama, Daisuke; Takahashi, Saeko; Nakamura, Morio; Takahashi, Takashi

2017-01-01

Group A Streptococcus (GAS, Streptococcus pyogenes ) causes invasive infections including streptococcal toxic shock syndrome (STSS) and local infections. To our knowledge, this is the first report of a case of an invasive GAS infection with pneumonia and pleural empyema (PE) followed by STSS (disseminated intravascular coagulation [DIC] and acute renal insufficiency) in a healthy male adult. He received combined supportive therapies of PE drainage, anti-DIC agent, hemodialysis, and antimicrobials and eventually made a clinical recovery. GAS isolated from PE was found to have emm1 / speA genes, suggestive of a pathogenic strain. Clinicians should be aware of the possibility of this disease entity (pneumonia, PE, and STSS) in healthy male adults as well as children and adult women.

Bacteremia due to Streptococcus tigurinus: A case report and literature review.

PubMed

Hirai, Jun; Sakanashi, Daisuke; Hagihara, Mao; Haranaga, Shusaku; Uechi, Kohei; Kato, Hideo; Hamada, Hiroyuki; Nishiyama, Naoya; Koizumi, Yusuke; Suematsu, Hiroyuki; Yamagishi, Yuka; Fujita, Jiro; Mikamo, Hiroshige

2016-11-01

Gene sequence analysis methods, including 16S rRNA identification, allows accurate identification of Streptococcus species, which include phenotypically closely related species that are difficult to differentiate using conventional chemical methods. We report a case of bacteremia due to Streptococcus tigurinus, identified by 16S rRNA, in a 72-year-old woman with gastrointestinal cancer and ascites. She was hospitalized to undergo elective tumor-related surgery. Five days prior to undergoing surgery, she developed a fever with no obvious source of infection. Blood cultures identified gram-positive cocci. The patient's bacteremia was initially thought to be caused by an Enterococcus species, given her underlying gastrointestinal disease. However, alpha-hemolytic, mucoid, circular colonies were observed on sheep blood agar the following day. Although matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and biochemical testing suggested Streptococcus pneumoniae, we conducted further investigation to identify the bacterium, as the patient had no symptoms of infections usually related with S. pneumoniae such as pneumonia, meningitis, or sinusitis, and the bacteremia occurred 30 days after hospitalization. Finally, the gram-positive cocci were identified as S. tigurinus, assigned to the Streptococcus mitis group in 2012. Although the origin of infection was unclear, it was suspected that peritonitis or bacterial translocation from the gastrointestinal tract caused the bacteremia. This novel species was recently reported as being extremely pathogenic and different from other Streptococcus species. It has been reported to occur in cases of infectious endocarditis and bacteremia. In this article, we reviewed previous reports of S. tigurinus infection and summarized the clinical and pathogenetic features. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Validation of an Immunodiagnostic Assay for Detection of 13 Streptococcus pneumoniae Serotype-Specific Polysaccharides in Human Urine

PubMed Central

Huijts, Susanne M.; Wu, Kangjian; Souza, Victor; Passador, Sherry; Tinder, Chunyan; Song, Esther; Elfassy, Arik; McNeil, Lisa; Menton, Ronald; French, Roger; Callahan, Janice; Webber, Chris; Gruber, William C.; Bonten, Marc J. M.; Jansen, Kathrin U.

2012-01-01

To improve the clinical diagnosis of pneumococcal infection in bacteremic and nonbacteremic community-acquired pneumonia (CAP), a Luminex technology-based multiplex urinary antigen detection (UAD) diagnostic assay was developed and validated. The UAD assay can simultaneously detect 13 different serotypes of Streptococcus pneumoniae by capturing serotype-specific S. pneumoniae polysaccharides (PnPSs) secreted in human urine. Assay specificity is achieved by capturing the polysaccharides with serotype-specific monoclonal antibodies (MAbs) on spectrally unique microspheres. Positivity for each serotype was based on positivity cutoff values calculated from a standard curve run on each assay plate together with positive- and negative-control urine samples. The assay is highly specific, since significant signals are detected only when each PnPS was paired with its homologous MAb-coated microspheres. Validation experiments demonstrated excellent accuracy and precision. The UAD assay and corresponding positivity cutoff values were clinically validated by assessing 776 urine specimens obtained from patients with X-ray-confirmed CAP. The UAD assay demonstrated 97% sensitivity and 100% specificity using samples obtained from patients with bacteremic, blood culture-positive CAP. Importantly, the UAD assay identified Streptococcus pneumoniae (13 serotypes) in a proportion of individuals with nonbacteremic CAP, a patient population for which the pneumococcal etiology of CAP was previously difficult to assess. Therefore, the UAD assay provides a specific, noninvasive, sensitive, and reproducible tool to support vaccine efficacy as well as epidemiological evaluation of pneumococcal disease, including CAP, in adults. PMID:22675155

Validation of an immunodiagnostic assay for detection of 13 Streptococcus pneumoniae serotype-specific polysaccharides in human urine.

PubMed

Pride, Michael W; Huijts, Susanne M; Wu, Kangjian; Souza, Victor; Passador, Sherry; Tinder, Chunyan; Song, Esther; Elfassy, Arik; McNeil, Lisa; Menton, Ronald; French, Roger; Callahan, Janice; Webber, Chris; Gruber, William C; Bonten, Marc J M; Jansen, Kathrin U

2012-08-01

To improve the clinical diagnosis of pneumococcal infection in bacteremic and nonbacteremic community-acquired pneumonia (CAP), a Luminex technology-based multiplex urinary antigen detection (UAD) diagnostic assay was developed and validated. The UAD assay can simultaneously detect 13 different serotypes of Streptococcus pneumoniae by capturing serotype-specific S. pneumoniae polysaccharides (PnPSs) secreted in human urine. Assay specificity is achieved by capturing the polysaccharides with serotype-specific monoclonal antibodies (MAbs) on spectrally unique microspheres. Positivity for each serotype was based on positivity cutoff values calculated from a standard curve run on each assay plate together with positive- and negative-control urine samples. The assay is highly specific, since significant signals are detected only when each PnPS was paired with its homologous MAb-coated microspheres. Validation experiments demonstrated excellent accuracy and precision. The UAD assay and corresponding positivity cutoff values were clinically validated by assessing 776 urine specimens obtained from patients with X-ray-confirmed CAP. The UAD assay demonstrated 97% sensitivity and 100% specificity using samples obtained from patients with bacteremic, blood culture-positive CAP. Importantly, the UAD assay identified Streptococcus pneumoniae (13 serotypes) in a proportion of individuals with nonbacteremic CAP, a patient population for which the pneumococcal etiology of CAP was previously difficult to assess. Therefore, the UAD assay provides a specific, noninvasive, sensitive, and reproducible tool to support vaccine efficacy as well as epidemiological evaluation of pneumococcal disease, including CAP, in adults.

A possible outbreak of Streptococcus pneumoniae invasive infection in children in Ibadan, Nigeria.

PubMed

Fashae, K F; Ogunsola, F T; Salawu, O M; Dada, A O; Popoola, O

2002-06-01

Streptococcus pneumoniae is an important aetiological agent of infections in children worldwide. The isolation rate of the bacteria has been strikingly low in the recent past in Nigeria. In a study of 1000 blood samples from patients, out of which 642 were from children in Ibadan between May 1999 and December 2000, 14 isolates of Streptococcus pneumoniae were obtained (a prevalence rate of 1.4%). All the isolates were from children and clustered between 13th September and 22nd October 1999, period of 40 days and thereafter no more organisms were isolated. Antibiotic sensitivity testing of all isolates by disc diffusion method showed resistance to cotrimoxazole, tetracycline and penicillin to be 14%, 21% and 36% respectively. All the isolates were sensitive to chloramphenicol and erythromycin. No fatalities were recorded among the children. This may have indicated an outbreak and underscores the urgency for an epidemiological database in Nigeria to ascertain the exact clinical burden of S. pnemoniae infections so as to determine the appropriate vaccine strategies required for Nigerian children.

Activity of Amoxicillin-Clavulanate against Penicillin-Resistant Streptococcus pneumoniae in an Experimental Respiratory Infection Model in Rats†

PubMed Central

Smith, Gillian M.; Slocombe, Brian; Abbott, Karen H.; Mizen, Linda W.

1998-01-01

High doses of amoxicillin, equivalent to those produced by 500- and 750-mg oral doses in humans (area under the plasma concentration-time curve), were effective against a penicillin-resistant strain of Streptococcus pneumoniae in an experimental respiratory tract infection in immunocompromised rats; this superior activity confirms the results of previous studies. An unexpected enhancement of amoxicillin’s antibacterial activity in vivo against penicillin-resistant and -susceptible S. pneumoniae strains was observed when subtherapeutic doses of amoxicillin were coadministered with the β-lactamase inhibitor potassium clavulanate. The reason for this enhancement was unclear since these organisms do not produce β-lactamase. The differential binding of clavulanic acid and amoxicillin to penicillin-binding proteins may have contributed to the observed effects. PMID:9559788

Identification of essential genes in Streptococcus pneumoniae by allelic replacement mutagenesis.

PubMed

Song, Jae-Hoon; Ko, Kwan Soo; Lee, Ji-Young; Baek, Jin Yang; Oh, Won Sup; Yoon, Ha Sik; Jeong, Jin-Yong; Chun, Jongsik

2005-06-30

To find potential targets of novel antimicrobial agents, we identified essential genes of Streptococcus pneumoniae using comparative genomics and allelic replacement mutagenesis. We compared the genome of S. pneumoniae R6 with those of Bacillus subtilis, Enterococcus faecalis, Escherichia coli, and Staphylococcus aureus, and selected 693 candidate target genes with > 40% amino acid sequence identity to the corresponding genes in at least two of the other species. The 693 genes were disrupted and 133 were found to be essential for growth. Of these, 32 encoded proteins of unknown function, and we were able to identify orthologues of 22 of these genes by genomic comparisons. The experimental method used in this study is easy to perform, rapid and efficient for identifying essential genes of bacterial pathogens.

Nonencapsulated Streptococcus pneumoniae causes otitis media during single-species infection and during polymicrobial infection with nontypeable Haemophilus influenzae

PubMed Central

Murrah, Kyle A.; Pang, Bing; Richardson, Stephen; Perez, Antonia; Reimche, Jennifer; King, Lauren; Wren, John; Swords, W. Edward

2014-01-01

Streptococcus pneumoniae strains lacking capsular polysaccharide have been increasingly reported in carriage and disease contexts. Since most cases of otitis media involve more than one bacterial species, we aimed to determine the capacity of a nonencapsulated S. pneumoniae clinical isolate to induce disease in the context of a single-species infection and as a polymicrobial infection with nontypeable Haemophilus influenzae. Using the chinchilla model of otitis media, we found that nonencapsulated S. pneumoniae colonizes the nasopharynx following intranasal inoculation, but does not readily ascend into the middle ear. However, when we inoculated nonencapsulated S. pneumoniae directly into the middle ear, the bacteria persisted for two weeks post-inoculation and induced symptoms consistent with chronic otitis media. During coinfection with nontypeable H. influenzae, both species persisted for one week and induced polymicrobial otitis media. We also observed that nontypeable H. influenzae conferred passive protection from killing by amoxicillin upon S. pneumoniae from within polymicrobial biofilms in vitro. Therefore, based on these results, we conclude that nonencapsulated pneumococci are a potential causative agent of chronic/recurrent otitis media, and can also cause mutualistic infection with other opportunists, which could complicate treatment outcomes. PMID:26014114

Nasopharyngeal carriage of Streptococcus pneumoniae in adults infected with human immunodeficiency virus in Jakarta, Indonesia.

PubMed

Harimurti, Kuntjoro; Saldi, Siti R F; Dewiasty, Esthika; Khoeri, Miftahuddin M; Yunihastuti, Evi; Putri, Tiara; Tafroji, Wisnu; Safari, Dodi

2016-01-01

This study investigated the distribution of serotype and antimicrobial susceptibility of Streptococcus pneumoniae carried by adults infected with human immunodeficiency virus (HIV) in Jakarta, Indonesia. Specimens of nasopharyngeal swab were collected from 200 HIV infected adults aged 21 to 63 years. Identification of S. pneumoniae was done by optochin susceptibility test and PCR for the presence of psaA and lytA genes. Serotyping was performed with sequential multiplex PCR and antibiotic susceptibility with the disk diffusion method. S. pneumoniae strains were carried by 10% adults with serotype 6A/B 20% was common serotype among cultured strains in 20 adults. Most of isolates were susceptible to chloramphenicol (80%) followed by clindamycin (75%), erythromycin (75%), penicillin (55%), and tetracycline (50%). This study found resistance to sulphamethoxazole/trimethoprim was most common with only 15% of strains being susceptible. High non-susceptibility to sulphamethoxazole/trimethoprim was observed in S. pneumoniae strains carried by HIV infected adults in Jakarta, Indonesia. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Antibiotic non-susceptibility among Streptococcus pneumoniae and Haemophilus influenzae isolates identified in African cohorts: a meta-analysis of three decades of published studies.

PubMed

Ginsburg, Amy Sarah; Tinkham, Laura; Riley, Katherine; Kay, Noa A; Klugman, Keith P; Gill, Christopher J

2013-12-01

Management of community-acquired pneumonia caused by Streptococcus pneumoniae and Haemophilus influenzae type B (Hib) can be complicated by emerging antimicrobial non-susceptibility. We conducted a meta-analysis to examine the antibiotic susceptibility of community-acquired invasive infections with S. pneumoniae and Hib in Africa from 1978 to 2011. With the notable exceptions of widespread trimethoprim/sulfamethoxazole (SXT) and tetracycline non-susceptibility, the majority of pneumococci remain susceptible to ampicillin/amoxicillin. However, 23.8% of pneumococcal meningitis isolates are non-susceptible to penicillin. Similarly, Hib isolates show non-susceptibility to SXT, tetracycline, erythromycin and chloramphenicol. β-Lactamase production among Hib isolates is increasing, a new observation for Africa, but is mitigated somewhat by Hib vaccination scale-up. In summary, pneumococcal susceptibility to amoxicillin remains high throughout Africa, and amoxicillin can be effectively and safely used as first-line treatment for childhood pneumonia. Data support first-line treatment of bacterial meningitis with ceftriaxone or cefotaxime. Copyright © 2013 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Evaluation of Iranian microbiology laboratories for identification of etiologic agents of bacterial meningitidis. Survey results of an external quality assessment scheme (EQAS) programme.

PubMed

Marandi, Farinaz Rashed; Rahbar, Mohammad; Sabourian, Roghieh; Saremi, Mahnaz

2010-01-01

To determine the ability of Iranian microbiology laboratories for identification and susceptibility testing of Streptococcus pneumoniae and Haemophilus influenzae as causative agents of bacterial meningitides. Two strains of bacteria including Haemophilus influenzae and Streptococcus pneumoniae as a common causative agents of meningitides were chosen and coded as strain number 1 and number 2. The strains were distributed among 679 microbiology laboratories. All laboratories were requested for identification of each unknown microorganism and susceptibility testing of S. pneumoniae against five commonly used antibiotics. Of 679 microbiology laboratories 310 (46%) laboratories participated in the survey and among these, 258 laboratories completely identified S. pneumoniae. About 85% laboratories produced correct susceptibility testing against oxacillin, erythromycin, tetracycline, and vancomycin. Of 310 received responses only 50 laboratories identified H. influenza correctly. The majority of the laboratories did not have the capacity to identification H. influenza. Microbiology laboratories in our country are qualified for identification and susceptibility testing of S. pneumoniae. However, majority of laboratories are not qualified for identification of H. influenzae.

Group A beta-haemolytic streptococcal acute chest event in a child with sickle cell anaemia.

PubMed

Suara, R O

2001-06-01

Acute chest syndrome is a major cause of death and hospitalisation in children with sickle cell anaemia. It is often initiated by an infection, particularly pneumonia. Microbial agents previously not associated with acute chest syndrome are becoming increasingly important. Group A beta-haemolytic Streptococcus (GABHS) is thought to be an uncommon cause of pneumonia in children with sickle cell anaemia. We report a 15-year-old African-American girl who presented with an acute chest event characterised by fever, cough, chest pain, shortness of breath, right upper abdominal quadrant pain, jaundice and otitis media. Chest radiograph showed multi-lobar pneumonia with left pleural effusion. Group A beta-haemolytic Streptococcus was isolated from culture of pleural and middle ear fluids. She responded to therapy that included antibiotics, exchange blood transfusion, oxygen, thoracotomy chest tube drainage and decortication. In a child with sickle cell anaemia presenting with fever and an acute chest event, pneumonia should be considered and GABHS recognised as a possible aetiological agent. In addition, a chest X-ray should be obtained and antibiotics against agents causing community-acquired pneumonia instituted.

Identification of Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid by multiplex real-time PCR.

PubMed

Sanz, Juan Carlos; Ríos, Esther; Rodríguez-Avial, Iciar; Ramos, Belén; Marín, Mercedes; Cercenado, Emilia

2017-08-14

The aim was to evaluate the utility of a multiplex real-time PCR to detect Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid (PF). A collection of 81 PF samples was used. Sixty were considered positive for S. pneumoniae according to previous results (54 by an in-house lytA gene PCR and eight by universal rRNA PCR). The sensitivity for detection of the lytA, plyA and psaA genes by multiplex PCR was 100% (60/60), 98.3% (59/60) and 91.7% (55/60), respectively. The detection of all three genes was negative in 21 samples formerly confirmed as negative for S. pneumoniae (100% specificity) by the other procedures (9 by in-house lytA PCR and 12 by rRNA PCR). The use of this multiplex PCR may be a useful option to identify S. pneumoniae directly in PF samples. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Efficacy of a new pharmacokinetically enhanced formulation of amoxicillin/clavulanate (2000/125 mg) in adults with community-acquired pneumonia caused by Streptococcus pneumoniae, including penicillin-resistant strains.

PubMed

File, Thomas M; Garau, Javier; Jacobs, Michael R; Wynne, Brian; Twynholm, Monique; Berkowitz, Elchonon

2005-02-01

Community-acquired pneumonia (CAP) is a common respiratory illness, frequently caused by Streptococcus pneumoniae. The prevalence of S. pneumoniae resistance to common antimicrobials has increased over recent years. A new pharmacokinetically enhanced formulation of amoxicillin/clavulanate (2000/125 mg) has been developed, designed to combat infections caused by S. pneumoniae, including penicillin-resistant (PRSP, penicillin minimum inhibitory concentrations (MICs) >or=2mg/l) isolates, and those with elevated amoxicillin/clavulanic acid MICs, while maintaining coverage of beta-lactamase-producing pathogens. A pooled efficacy analysis of four randomized (1:1) and one non-comparative clinical trials of amoxicillin/clavulanate, 2000/125 mg, given twice daily, was conducted in adult patients with CAP. Comparator agents were conventional amoxicillin/clavulanate formulations. At follow-up (days 16-39), efficacy (eradication of the initial pathogen or clinical cure in patients for whom no repeat culture was performed) in patients with S. pneumoniae infection was 92.3% (274/297) for amoxicillin/clavulanate, 2000/125 mg and 85.2% (46/54) for comparators (P=0.11). Twenty-four of 25 PRSP-infected patients receiving amoxicillin/clavulanate, 2000/125 mg were treated successfully. Both amoxicillin/clavulanate, 2000/125 mg and comparators were well tolerated, with few patients withdrawing from the studies.

Transgenic Expression of Bcl-xL or Bcl-2 by Murine B Cells Enhances the In Vivo Antipolysaccharide, but Not Antiprotein, Response to Intact Streptococcus pneumoniae

DTIC Science & Technology

2007-01-01

primary IgG anti-PS, vs antiprotein, re- sponse and a greater dependence on B cell membrane Ig (mIg) signaling, mediated by Bruton’s tyrosine kinase ( Btk ...WT, wild type; TI, T cell independent; TD, T cell dependent; Pn, Streptococcus pneumoniae; mIg, membrane Ig; Btk , Bruton’s tyrosine kinase; GC...were more dependent than antiprotein responses, on Btk -dependent mIg FIGURE 2. Anti-PS responses to PPS14-PspA C-PS-PspA conjugate vaccine or to

A novel mutation in the alpha-helix 1 of the C subunit of the F(1)/F(0) ATPase responsible for optochin resistance of a Streptococcus pneumoniae clinical isolate.

PubMed

Cogné, N; Claverys, J; Denis, F; Martin, C

2000-10-01

Previously reported mutations involved in optochin resistance of Streptococcus pneumoniae clinical isolates changed residues 48, 49 or 50, in the transmembrane alpha-helix 2 of the F(1)/F(0) ATPase subunit. We report here an unusual mutation which changes the sequence of the transmembrane alpha-helix 1 of the AtpC subunit. This mutation involves a Gly to Ser substitution resulting from a G to A transition at codon 14 of the atpC gene.

Co-infection of Influenza B and Streptococci causing severe pneumonia and septic shock in healthy women

PubMed Central

2010-01-01

Background Since the Influenza A pandemic in 1819, the association between the influenza virus and Streptococcus pneumoniae has been well described in literature. While a leading role has been so far attributed solely to Influenza A as the primary infective pathogen, Influenza B is generally considered to be less pathogenic with little impact on morbidity and mortality of otherwise healthy adults. This report documents the severe synergistic pathogenesis of Influenza B infection and bacterial pneumonia in previously healthy persons not belonging to a special risk population and outlines therapeutic options in this clinical setting. Case Presentation During the seasonal influenza epidemic 2007/2008, three previously healthy women presented to our hospital with influenza-like symptoms and rapid clinical deterioration. Subsequent septic shock due to severe bilateral pneumonia necessitated intensive resuscitative measures including the use of an interventional lung assist device. Microbiological analysis identified severe dual infections of Influenza B with Streptococcus pyogenes in two cases and Streptococcus pneumoniae in one case. The patients presented with no evidence of underlying disease or other known risk factors for dual infection such as age (< one year, > 65 years), pregnancy or comorbidity. Conclusions Influenza B infection can pose a risk for severe secondary infection in previously healthy persons. As patients admitted to hospital due to severe pneumonia are rarely tested for Influenza B, the incidence of admission due to this virus might be greatly underestimated, therefore, a more aggressive search for influenza virus and empirical treatment might be warranted. While the use of an interventional lung assist device offers a potential treatment strategy for refractory respiratory acidosis in addition to protective lung ventilation, the combined empiric use of a neuraminidase-inhibitor and antibiotics in septic patients with pulmonary manifestations during an epidemic season should be considered. PMID:20979628

Streptococcus pneumoniae-induced ototoxicity in organ of Corti explant cultures.

PubMed

Perny, Michael; Solyga, Magdalena; Grandgirard, Denis; Roccio, Marta; Leib, Stephen L; Senn, Pascal

2017-07-01

Hearing loss remains the most common long-term complication of pneumococcal meningitis (PM) reported in up to 30% of survivors. Streptococcus pneumoniae have been shown to possess different ototoxic properties. Here we present a novel ex vivo experimental setup to examine in detail the pattern of hair cell loss upon exposure to different S. pneumoniae strains, therefore recapitulating pathogen derived aspects of PM-induced hearing loss. Our results show a higher susceptibility towards S. pneumoniae-induced cochlear damage for outer hair cells (OHC) compared to inner hair cells (IHC), which is consistent with in vivo data. S. pneumoniae-induced hair cell loss was both time and dose-dependent. Moreover, we have found significant differences in the level of cell damage between tissue from the basal and the apical turns. This shows that the higher vulnerability of hair cells located at high frequency regions observed in vivo cannot be explained solely by the spatial organisation and bacterial infiltration from the basal portion of the cochlea. Using a wild type D39 strain and a mutant defective for the pneumolysin (PLY) gene, we also have shown that the toxin PLY is an important factor involved in ototoxic damages. The obtained results indicate that PLY can cause both IHC and OHC loss. Finally, we are reporting here for the first time a higher vulnerability of HC located at the basal and middle cochlear region to pneumolysin-induced damage. The detailed description of the susceptibility of hair cells to Streptococcus pneumoniae provided in this report can in the future determine the choice and the development of novel otoprotective therapies during pneumococcal meningitis. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Mathematical modeling of postcoinfection with influenza A virus and Streptococcus pneumoniae, with implications for pneumonia and COPD-risk assessment.

PubMed

Cheng, Yi-Hsien; You, Shu-Han; Lin, Yi-Jun; Chen, Szu-Chieh; Chen, Wei-Yu; Chou, Wei-Chun; Hsieh, Nan-Hung; Liao, Chung-Min

2017-01-01

The interaction between influenza and pneumococcus is important for understanding how coinfection may exacerbate pneumonia. Secondary pneumococcal pneumonia associated with influenza infection is more likely to increase respiratory morbidity and mortality. This study aimed to assess exacerbated inflammatory effects posed by secondary pneumococcal pneumonia, given prior influenza infection. A well-derived mathematical within-host dynamic model of coinfection with influenza A virus and Streptococcus pneumoniae (SP) integrated with dose-response relationships composed of previously published mouse experimental data and clinical studies was implemented to study potentially exacerbated inflammatory responses in pneumonia based on a probabilistic approach. We found that TNFα is likely to be the most sensitive biomarker reflecting inflammatory response during coinfection among three explored cytokines. We showed that the worst inflammatory effects would occur at day 7 SP coinfection, with risk probability of 50% (likely) to develop severe inflammatory responses. Our model also showed that the day of secondary SP infection had much more impact on the severity of inflammatory responses in pneumonia compared to the effects caused by initial virus titers and bacteria loads. People and health care workers should be wary of secondary SP infection on day 7 post-influenza infection for prompt and proper control-measure implementation. Our quantitative risk-assessment framework can provide new insights into improvements in respiratory health especially, predominantly due to chronic obstructive pulmonary disease (COPD).

[Examination about utility of a Streptococcus pneumoniae capsular antigen swiftness search kit urine in a pneumonia patient].

PubMed

Hashikita, Giichi; Yamaguti, Toshiyuki; Tachi, Yoshimi; Kishi, Etsuko; Kawamura, Toru; Takahashi, Shun; Arai, Yukie; Koyama, Sachie; Huruhata, Toshihumi; Itabashi, Akira; Oka, Yoko; Yamazaki, Tsutomu; Maesaki, Sigefumi

2005-01-01

We investigated the usefullness of Binax NOW urine antigen test, an immunochromatographic assay that binds any soluble Streptococcus pneumoniae antigen (C polysaccharide) for the diagnosis of penumoniae form September 2003 to March 2005. We used 372 samples form the patinets with pneumoniae diagnosed for blood or sputum cultuter or gram-stained sputum smear. Out of 24 culture positive specimens, Binax NOW urine antigen test, showed positive in 18 (75%) specimens. The sensitivity of sputum and blood culture was 71.7% and 83.3%, respectively. Binax NOW urine antigen test was seemed false positives in 55 samples, false negatives in 6 samples. The specificity of Binax NOW urine antigen test was evaluated 84.1%. Overall agreement among tests was 83.6%. When compared to culture, false negative urine antigen may be the result of colonizing S. pneumoniae in sputum or pneumonia caused by an agent other than S. pneumoniae. CRP values for cases were both urine antigen and culture were positive ranged from 40 mg/dl to 10 mg/dl while urine antigen and culture negative cases were predominantly less than 10 mg/dl. Positive blood and pleural fluid culture cases were consistently associated with strongly positive urine antigen tests. Non-agreement between urine antigen, culture, and microscopy may be the result of specimen quality, labile nature of S. pneumoniae and antimicrobial therapy.

Detection of Haemophilus influenzae type b, Streptococcus agalactiae, Streptococcus pneumoniae and Neisseria meningitidis in CSF specimens of children suspicious of Meningitis in Ahvaz, Iran.

PubMed

Amin, Mansour; Ghaderpanah, Mozhgan; Navidifar, Tahereh

2016-10-01

Meningitis is a life-threatening infection associated with a high mortality and morbidity worldwide. Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae are the most prevalent infectious agents that cause bacterial meningitis (BM). The objective of this study was to determine the frequencies of these three bacteria using bacterial cultures and polymerase chain reaction (PCR). In our cross-sectional study, cerebrospinal fluid (CSF) specimens were obtained from 196 patients who were suspected of having BM and referred to the pediatric ward of Abuzar Hospital (Ahvaz, Iran). The samples were monitored by gram stain, cultures, and the PCR method. The patients' age mean was 23 ± 0.56 months. The 196 patients comprised 92 (46.9%) boys and 104 (53.06%) girls. Based on bacterial cultures, just three isolates of H. influenzae were detected. However, PCR detected this bacterium in eight patients. Streptococcus pneumoniae was detected in five (2.5%) patients by the amplification of the lytA gene and in one (0.5%) patient by ply. In this study, no N. meningitidis isolate was in the CSF samples, based on the bacterial culture or PCR results. Streptococcus agalactiae was detected only in one patient, based on PCR. In conclusion, in the present study, the PCR method was more sensitive and rapid than culture for detecting the infectious agents in BM. For this reason, this diagnosis method is recommended for BM. Copyright © 2016. Published by Elsevier Taiwan.

Virome and bacteriome characterization of children with pneumonia and asthma in Mexico City during winter seasons 2014 and 2015.

PubMed

Romero-Espinoza, Jose A; Moreno-Valencia, Yazmin; Coronel-Tellez, Rodrigo H; Castillejos-Lopez, Manuel; Hernandez, Andres; Dominguez, Aaron; Miliar-Garcia, Angel; Barbachano-Guerrero, Arturo; Perez-Padilla, Rogelio; Alejandre-Garcia, Alejandro; Vazquez-Perez, Joel A

2018-01-01

Acute asthma exacerbations and pneumonia are important causes of morbidity and mortality in children and may coexist in the same children, although symptom overlap may lead to difficulties in diagnosis. Microbial and viral diversity and differential abundance of either may play an important role in infection susceptibility and the development of acute and chronic respiratory diseases. To describe the virome and bacteriome present in the upper respiratory tract of hospitalized children with a clinical diagnosis of asthma and pneumonia during an acute exacerbation and an acute respiratory illness ARI episode respectively. During the winter seasons of 2013-2014 and 2014-2015, 134 nasopharyngeal swabs samples of children <15 years of age with ARI hospitalized at a referral hospital for respiratory diseases were selected based on clinical diagnosis of asthma or pneumonia. The virome and bacteriome were characterized using Whole Genome Sequencing (WGS) and in-house bioinformatics analysis pipeline. The Asthma group was represented mainly by RV-C, BoV-1 and RSV-B and the pneumonia group by Bacteriophage EJ-1 and TTMV. TTV was found in both groups with a similar amount of reads. About bacterial composition Moraxella catarrhalis, Propionibacterium acnes and Acinetobacter were present in asthma and Veillonella parvula and Mycoplasma pneumoniae in pneumonia. Streptococcus pneumoniae and Haemophilus influenzae were mostly found with both asthma and pneumonia. Our results show a complex viral and bacterial composition in asthma and pneumonia groups with a strong association of RV-C presence in asthmatic children. We observed Streptococcus pneumoniae and Haemophilus influenzae concurrently in both groups.

Inactivation of the srtA Gene Affects Localization of Surface Proteins and Decreases Adhesion of Streptococcus pneumoniae to Human Pharyngeal Cells In Vitro

PubMed Central

Kharat, Arun S.; Tomasz, Alexander

2003-01-01

Inactivation of sortase gene srtA in Streptococcus pneumoniae strain R6 caused the release of β-galactosidase and neuraminidase A (NanA) from the cell wall into the surrounding medium. Both of these surface proteins contain the LPXTG motif in the C-terminal domain. Complementation with plasmid-borne srtA reversed protein release. Deletion of murM, a gene involved in the branching of pneumococcal peptidoglycan, also caused partial release of β-galactosidase, suggesting preferential attachment of the protein to branched muropeptides in the cell wall. Inactivation of srtA caused decreased adherence to human pharyngeal cells in vitro but had no effect on the virulence of a capsular type III strain of S. pneumoniae in the mouse intraperitoneal model. The observations suggest that—as in other gram-positive bacteria—sortase-dependent display of proteins occurs in S. pneumoniae and that some of these proteins may be involved in colonization of the human host. PMID:12704150

Phosphorylation of the Streptococcus pneumoniae cell wall biosynthesis enzyme MurC by a eukaryotic-like Ser/Thr kinase.

PubMed

Falk, Shaun P; Weisblum, Bernard

2013-03-01

Streptococcus pneumoniae contains a single Ser/Thr kinase-phosphatase pair known as StkP-PhpP. Here, we report the interaction of StkP-PhpP with S. pneumoniae UDP-N-acetylmuramoyl:L-alanine ligase, MurC, an enzyme that synthesizes an essential intermediate of the cell wall peptidoglycan pathway. Combinatorial phage display using StkP as target selected the peptide sequence YEVCGSDTVGC as an interacting partner and subsequently confirmed by ELISA. The phage peptide sequence YEVCGSDTVGC aligns closely with the MurC motif spanning S. pneumoniae amino acid coordinates 31-37. We show that MurC is phosphorylated by StkP and that phosphoMurC is dephosphorylated by PhpP. These data suggest a link between StkP-PhpP with the coordinated regulation of cell wall biosynthesis via MurC. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Treatment of acute bacterial rhinosinusitis caused by antimicrobial-resistant Streptococcus pneumoniae.

PubMed

Anon, Jack B

2004-08-02

Acute bacterial rhinosinusitis (ABRS) is a secondary bacterial infection of the nose and paranasal sinuses, usually preceded by a viral upper respiratory infection or allergy, with symptoms that have not improved after 10 days or that have worsened after 5 to 7 days. Streptococcus pneumoniae and Haemophilus influenzae are the most common causes of ABRS in adults. Increasing rates of antimicrobial resistance among S. pneumoniae and beta-lactamase production among H. influenzae are formidable challenges to the successful treatment of infections caused by these organisms. To this end, various formulations of amoxicillin-clavulanate have been developed, the most recent of which is pharmacokinetically enhanced and provides a total daily dose of 4,000 mg of amoxicillin and 250 mg of clavulanate. This formulation has been shown to be safe and effective in the treatment of infections caused by penicillin-resistant S. pneumoniae (minimum inhibitory concentration 2 microg/mL); the clavulanate component provides adequate coverage of beta-lactamase-producing pathogens.

Comparative analysis of growth-phase-dependent gene expression in virulent and avirulent Streptococcus pneumoniae using a high-density DNA microarray.

PubMed

Ko, Kwan Soo; Park, Sulhee; Oh, Won Sup; Suh, Ji-Yoeun; Oh, Taejeong; Ahn, Sungwhan; Chun, Jongsik; Song, Jae-Hoon

2006-02-28

The global pattern of growth-dependent gene expres-sion in Streptococcus pneumoniae strains was evalu-ated using a high-density DNA microarray. Total RNAs obtained from an avirulent S. pneumoniae strain R6 and a virulent strain AMC96-6 were used to compare the expression patterns at seven time points (2.5, 3.5, 4.5, 5.5, 6.0, 6.5, and 8.0 h). The expression profile of strain R6 changed between log and station-ary growth (the Log-Stat switch). There were clear differences between the growth-dependent gene ex-pression profiles of the virulent and avirulent pneumo-coccal strains in 367 of 1,112 genes. Transcripts of genes associated with bacterial competence and capsular polysaccharide formation, as well as clpP and cbpA, were higher in the virulent strain. Our data suggest that late log or early stationary phase may be the most virulent phase of S. pneumoniae.

The novel species Streptococcus tigurinus and its association with oral infection.

PubMed

Zbinden, Andrea; Bostanci, Nagihan; Belibasakis, Georgios N

2015-01-01

Streptococcus tigurinus is a novel species of viridans streptococci, shown to cause severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. S. tigurinus belongs to the Streptococcus mitis group and is most closely related to Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae and Streptococcus infantis. The presence of S. tigurinus in the human oral cavity has been documented, including in patients with periodontal disease. This review addresses the available scientific knowledge on S. tigurinus and its association with closely related streptococci, and discusses its putative involvement in common oral infections. While there is as yet no strong evidence on the involvement of S. tigurinus with oral infections, its presence in the oral cavity and its association with endocarditis warrants special attention for a link between oral and systemic infection.

Fluorocycline TP-271 Is Potent against Complicated Community-Acquired Bacterial Pneumonia Pathogens

PubMed Central

Fyfe, Corey; O’Brien, William; Hackel, Meredith; Minyard, Mary Beth; Waites, Ken B.; Dubois, Jacques; Murphy, Timothy M.; Slee, Andrew M.; Weiss, William J.; Sutcliffe, Joyce A.

2017-01-01

ABSTRACT TP-271 is a novel, fully synthetic fluorocycline antibiotic in clinical development for the treatment of respiratory infections caused by susceptible and multidrug-resistant pathogens. TP-271 was active in MIC assays against key community respiratory Gram-positive and Gram-negative pathogens, including Streptococcus pneumoniae (MIC90 = 0.03 µg/ml), methicillin-sensitive Staphylococcus aureus (MSSA; MIC90 = 0.25 µg/ml), methicillin-resistant S. aureus (MRSA; MIC90 = 0.12 µg/ml), Streptococcus pyogenes (MIC90 = 0.03 µg/ml), Haemophilus influenzae (MIC90 = 0.12 µg/ml), and Moraxella catarrhalis (MIC90 ≤0.016 µg/ml). TP-271 showed activity (MIC90 = 0.12 µg/ml) against community-acquired MRSA expressing Panton-Valentine leukocidin (PVL). MIC90 values against Mycoplasma pneumoniae, Legionella pneumophila, and Chlamydia pneumoniae were 0.004, 1, and 4 µg/ml, respectively. TP-271 was efficacious in neutropenic and immunocompetent animal pneumonia models, generally showing, compared to the burden at the start of dosing, ~2 to 5 log10 CFU reductions against MRSA, S. pneumoniae, and H. influenzae infections when given intravenously (i.v.) and ~1 to 4 log10 CFU reductions when given orally (p.o.). TP-271 was potent against key community-acquired bacterial pneumonia (CABP) pathogens and was minimally affected, or unaffected, by tetracycline-specific resistance mechanisms and fluoroquinolone or macrolide drug resistance phenotypes. IMPORTANCE Rising resistance rates for macrolides, fluoroquinolones, and β-lactams in the most common pathogens associated with community-acquired bacterial pneumonia (CABP) are of concern, especially for cases of moderate to severe infections in vulnerable populations such as the very young and the elderly. New antibiotics that are active against multidrug-resistant Streptococcus pneumoniae and Staphylococcus aureus are needed for use in the empirical treatment of the most severe forms of this disease. TP-271 is a promising new fluorocycline antibiotic demonstrating in vitro potency and nonclinical efficacy by intravenous and oral administration against the major pathogens associated with moderate to severe CABP. PMID:28251179

Frequency of Spontaneous Resistance to Peptide Deformylase Inhibitor GSK1322322 in Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae.

PubMed

Min, Sharon; Ingraham, Karen; Huang, Jianzhong; McCloskey, Lynn; Rilling, Sarah; Windau, Anne; Pizzollo, Jason; Butler, Deborah; Aubart, Kelly; Miller, Linda A; Zalacain, Magdalena; Holmes, David J; O'Dwyer, Karen

2015-08-01

The continuous emergence of multidrug-resistant pathogenic bacteria is compromising the successful treatment of serious microbial infections. GSK1322322, a novel peptide deformylase (PDF) inhibitor, shows good in vitro antibacterial activity and has demonstrated safety and efficacy in human proof-of-concept clinical studies. In vitro studies were performed to determine the frequency of resistance (FoR) to this antimicrobial agent in major pathogens that cause respiratory tract and skin infections. Resistance to GSK1322322 occurred at high frequency through loss-of-function mutations in the formyl-methionyl transferase (FMT) protein in Staphylococcus aureus (4/4 strains) and Streptococcus pyogenes (4/4 strains) and via missense mutations in Streptococcus pneumoniae (6/21 strains), but the mutations were associated with severe in vitro and/or in vivo fitness costs. The overall FoR to GSK1322322 was very low in Haemophilus influenzae, with only one PDF mutant being identified in one of four strains. No target-based mutants were identified from S. pyogenes, and only one or no PDF mutants were isolated in three of the four S. aureus strains studied. In S. pneumoniae, PDF mutants were isolated from only six of 21 strains tested; an additional 10 strains did not yield colonies on GSK1322322-containing plates. Most of the PDF mutants characterized from those three organisms (35/37 mutants) carried mutations in residues at or in close proximity to one of three highly conserved motifs that are part of the active site of the PDF protein, with 30 of the 35 mutations occurring at position V71 (using the S. pneumoniae numbering system). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Occurrence and Evolution of the Paralogous Zinc Metalloproteases IgA1 Protease, ZmpB, ZmpC, and ZmpD in Streptococcus pneumoniae and Related Commensal Species

PubMed Central

Bek-Thomsen, Malene; Poulsen, Knud; Kilian, Mogens

2012-01-01

ABSTRACT The distribution, genome location, and evolution of the four paralogous zinc metalloproteases, IgA1 protease, ZmpB, ZmpC, and ZmpD, in Streptococcus pneumoniae and related commensal species were studied by in silico analysis of whole genomes and by activity screening of 154 representatives of 20 species. ZmpB was ubiquitous in the Mitis and Salivarius groups of the genus Streptococcus and in the genera Gemella and Granulicatella, with the exception of a fragmented gene in Streptococcus thermophilus, the only species with a nonhuman habitat. IgA1 protease activity was observed in all members of S. pneumoniae, S. pseudopneumoniae, S. oralis, S. sanguinis, and Gemella haemolysans, was variably present in S. mitis and S. infantis, and absent in S. gordonii, S. parasanguinis, S. cristatus, S. oligofermentans, S. australis, S. peroris, and S. suis. Phylogenetic analysis of 297 zmp sequences and representative housekeeping genes provided evidence for an unprecedented selection for genetic diversification of the iga, zmpB, and zmpD genes in S. pneumoniae and evidence of very frequent intraspecies transfer of entire genes and combination of genes. Presumably due to their adaptation to a commensal lifestyle, largely unaffected by adaptive mucosal immune factors, the corresponding genes in commensal streptococci have remained conserved. The widespread distribution and significant sequence diversity indicate an ancient origin of the zinc metalloproteases predating the emergence of the humanoid species. zmpB, which appears to be the ancestral gene, subsequently duplicated and successfully diversified into distinct functions, is likely to serve an important but yet unknown housekeeping function associated with the human host. PMID:23033471

Potentiality of standardized extract and isolated flavonoids from Zuccagnia punctata for the treatment of respiratory infections by Streptococcus pneumoniae: in vitro and in vivo studies.

PubMed

Zampini, I C; Villena, J; Salva, S; Herrera, M; Isla, M I; Alvarez, S

2012-03-27

Zuccagnia punctata Cav. (Fabaceae) is a monotypic species distributed in western Argentina and is traditionally used for the treatment of bacterial and fungal infections. The aim of this study was to demonstrated the antibacterial activity of the Zuccagnia punctata standardized extract and the structurally related non-methoxylated flavonoids with similar pattern of substitution and differences in ring C present in this plant species: 7-hydroxyflavanone (HF), 2',4'-dihydroxychalcone (DHC) and 3,7-dihydroxyflavone (DHF), against Streptococcus pneumoniae clinical isolates using in vitro and in vivo models. MIC values of natural products were determined by agar macrodilution method. In vivo activities were investigated in a Streptococcus pneumoniae infection model in mice. Lung and blood samples were obtained for bacterial cell counts. The serum was used by biochemical analysis (alanine transaminase, aspartate transaminase, urea and creatinine) in order to evaluate the toxicity of natural products. All samples showed antimicrobial activity in vitro with MIC values between 50 and 500μg/ml. Zuccagnia punctata extract (1mg/mice) and HF (1mg/mice) significantly reduced the number of viable Streptococcus pneumoniae in lung (p<0.01) while lower quantities has not effect. Therefore, the present study has shown that intake once or twice a day of 1mg of Zuccagnia punctata extract or HF for seven days did not result in toxicity. Our results showed that Zuccagnia punctata extract as well as one of its isolated flavonoids, 7-hydroxyflavanone, could be useful for the development of a novel respiratory infections treatment. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Frequency of Spontaneous Resistance to Peptide Deformylase Inhibitor GSK1322322 in Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae

PubMed Central

Ingraham, Karen; Huang, Jianzhong; McCloskey, Lynn; Rilling, Sarah; Windau, Anne; Pizzollo, Jason; Butler, Deborah; Aubart, Kelly; Miller, Linda A.; Zalacain, Magdalena; Holmes, David J.; O'Dwyer, Karen

2015-01-01

The continuous emergence of multidrug-resistant pathogenic bacteria is compromising the successful treatment of serious microbial infections. GSK1322322, a novel peptide deformylase (PDF) inhibitor, shows good in vitro antibacterial activity and has demonstrated safety and efficacy in human proof-of-concept clinical studies. In vitro studies were performed to determine the frequency of resistance (FoR) to this antimicrobial agent in major pathogens that cause respiratory tract and skin infections. Resistance to GSK1322322 occurred at high frequency through loss-of-function mutations in the formyl-methionyl transferase (FMT) protein in Staphylococcus aureus (4/4 strains) and Streptococcus pyogenes (4/4 strains) and via missense mutations in Streptococcus pneumoniae (6/21 strains), but the mutations were associated with severe in vitro and/or in vivo fitness costs. The overall FoR to GSK1322322 was very low in Haemophilus influenzae, with only one PDF mutant being identified in one of four strains. No target-based mutants were identified from S. pyogenes, and only one or no PDF mutants were isolated in three of the four S. aureus strains studied. In S. pneumoniae, PDF mutants were isolated from only six of 21 strains tested; an additional 10 strains did not yield colonies on GSK1322322-containing plates. Most of the PDF mutants characterized from those three organisms (35/37 mutants) carried mutations in residues at or in close proximity to one of three highly conserved motifs that are part of the active site of the PDF protein, with 30 of the 35 mutations occurring at position V71 (using the S. pneumoniae numbering system). PMID:26014938

Fatal Necrotizing Fasciitis Due to Streptococcus pneumoniae: A Case Report

PubMed Central

Park, So-Youn; Park, So Young; Moon, Soo-youn; Son, Jun Seong

2011-01-01

Necrotizing fasciitis is known to be a highly lethal infection of deep-seated subcutaneous tissue and superficial fascia. Reports of necrotizing fasciitis due to Streptococcus pneumoniae are exceedingly rare. We report a case of necrotizing fasciitis in a 62-yr-old man with liver cirrhosis and diabetes mellitus. He presented with painful swelling of left leg and right hand. On the day of admission, compartment syndrome was aggravated and the patient underwent surgical exploration. Intra-operative findings revealed necrotizing fasciitis and cultures of two blood samples and wound aspirates showed S. pneumoniae. The patient died despite debridement and proper antimicrobial treatment. To the best of our knowledge, this is the first case of fatal necrotizing fasciitis with meningitis reported in Korea. We also review and discuss the literature on pneumococcal necrotizing fasciitis. PMID:21218041

Effect and mechanism of calpains on pediatric lobar pneumonia.

PubMed

Yin, Genquan; Zeng, Qiang; Zhao, Haijin; Wu, Peiqiong; Cai, Shaoxi; Deng, Li; Jiang, Wenhui

2017-07-04

Lobar pneumonia, one of the community-acquired pneumonia (CAP), is a common pediatric low respiratory tract infection. Calpains are Ca 2+ -activated cysteine proteases whose activation mechanism is elusive. The present study was undertaken to detect the role and mechanism of calpains in pediatric lobar pneumonia. The human acute lung infection model (ALIM) was constructed and infected by Streptococcus. Enzyme-linked immunosorbent assay (ELISA) was used to measure interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-α. We observed the lactate dehydrogenase (LDH) release, calpains activity and calpain inhibitor effects in ALIM. The expression of proliferating cell nuclear antigen (PCNA) protein was quantified by western blotting. Then the effects of calpain 1 and 2 knockdown on expressions of inflammation factors and PCNA protein, LDH release and apoptosis were evaluated in lung MRC-5 cells. In constructed ALIM, expressions of IL-6 (P < 0.01), IL-8 (P < 0.01), TNF-α (P < 0.05) and PCNA protein (P < 0.05) were significantly reduced by the calpain inhibitor. Expressions of IL-6, IL-8, TNF-α, PCNA protein and relative LDH release were statistically reduced by the small interfering (si) RNA-calpain 1 and 2 in MRC-5 cells (P < 0.05). Calpains silence increased apoptotic cells from 5% (negative control) to more than 20% in MRC-5 cells. The present study suggests that calpains possess a significant effect on inflammations, cell proliferation and apoptosis. Suppression of calpains may provide a potential therapeutic target of lobar pneumonia.

Efficacy and safety of twice-daily pharmacokinetically enhanced amoxicillin/clavulanate (2000/125 mg) in the treatment of adults with community-acquired pneumonia in a country with a high prevalence of penicillin-resistant Streptococcus pneumoniae.

PubMed

Siquier, B; Sánchez-Alvarez, J; García-Mendez, E; Sabriá, M; Santos, J; Pallarés, R; Twynholm, M; Dal-Ré, R

2006-03-01

This randomized, double-blind, non-inferiority trial evaluated the efficacy and safety of pharmacokinetically enhanced amoxicillin/clavulanate 2000/125 mg twice daily versus amoxicillin/clavulanate 875/125 mg three times daily, both given orally for 7 or 10 days, in the treatment of adults with community-acquired pneumonia in Spain, a country with a high prevalence of penicillin-resistant Streptococcus pneumoniae. Following 2:1 randomization, 566 patients (intent-to-treat population) received either amoxicillin/clavulanate 2000/125 mg (n = 374) or amoxicillin/clavulanate 875/125 mg (n = 192). Among the patients who did not deviate from the protocol (clinical per-protocol population), clinical success at day 21-28 post-therapy (test of cure; primary efficacy endpoint) was 92.4% (266/288) for amoxicillin/clavulanate 2000/125 mg and 91.2% (135/148) for amoxicillin/clavulanate 875/125 mg (treatment difference, 1.1; 95% confidence interval, -4.4, 6.6). Bacteriological success at test of cure in the bacteriology per-protocol population was 90.8% (79/87) with amoxicillin/clavulanate 2000/125 mg and 86.0% (43/50) with amoxicillin/clavulanate 875/125 mg (treatment difference 4.8; 95% confidence interval, -6.6, 16.2). At test of cure, amoxicillin/clavulanate 2000/125 mg was clinically and bacteriologically effective against 7/7 penicillin-resistant Streptococcus pneumoniae (MIC > or = 2 mg/L) isolates (including three amoxicillin non-susceptible strains) and amoxicillin/clavulanate 875/125 mg against 5/5 isolates (including one amoxicillin non-susceptible strain). Both treatment regimens were well tolerated. Amoxicillin/clavulanate 2000/125 mg was at least as effective clinically and as safe as amoxicillin/clavulanate 875/125 mg in the treatment of community-acquired pneumonia in adults in a country with a high prevalence of penicillin-resistant S. pneumoniae and has a more convenient twice daily posology.

Pneumococcal Disease Fast Facts

MedlinePlus

... Vaccination For Clinicians Streptococcus pneumoniae Transmission Clinical Features Risk Factors Diagnosis & Management Prevention For Laboratorians Drug Resistance Surveillance & Reporting Global ...

Peritoneal Culture Alters Streptococcus pneumoniae Protein Profiles and Virulence Properties

PubMed Central

Orihuela, Carlos J.; Janssen, Rob; Robb, Christopher W.; Watson, David A.; Niesel, David W.

2000-01-01

We have examined the properties of Streptococcus pneumoniae cultured in the murine peritoneal cavity and compared its virulence-associated characteristics to those of cultures grown in vitro. Analysis of mRNA levels for specific virulence factors demonstrated a 2.8-fold increase in ply expression and a 2.2-fold increase in capA3 expression during murine peritoneal culture (MPC). Two-dimensional gels and immunoblots using convalescent-phase patient sera and murine sera revealed distinct differences in protein production in vivo (MPC). MPC-grown pneumococci adhered to A549 epithelial cell lines at levels 10-fold greater than those cultured in vitro. PMID:10992528

[Group A streptococcal meningitis: Streptococcus pneumoniae is not the only one to seep into the CSF fluid leak!].

PubMed

Zappella, N; Barrelet, A; Pangon, B; Laurent, V; Bruneel, F

2013-11-01

We reported a case of group A streptococcal meningitis in a patient with a CSF fluid leak. This case underlined several relevant points: (i) an unfrequent cause of bacterial meningitis; (ii) the main diagnosis to evoke when the direct examination of CSF shows Gram+ cocci with a negative pneumococcal antigen; (iii) that bacteria other than Streptococcus pneumoniae are possible in front of a meningitis associated with a CSF fluif leak. Copyright © 2013 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

Peritoneal culture alters Streptococcus pneumoniae protein profiles and virulence properties

NASA Technical Reports Server (NTRS)

Orihuela, C. J.; Janssen, R.; Robb, C. W.; Watson, D. A.; Niesel, D. W.

2000-01-01

We have examined the properties of Streptococcus pneumoniae cultured in the murine peritoneal cavity and compared its virulence-associated characteristics to those of cultures grown in vitro. Analysis of mRNA levels for specific virulence factors demonstrated a 2.8-fold increase in ply expression and a 2.2-fold increase in capA3 expression during murine peritoneal culture (MPC). Two-dimensional gels and immunoblots using convalescent-phase patient sera and murine sera revealed distinct differences in protein production in vivo (MPC). MPC-grown pneumococci adhered to A549 epithelial cell lines at levels 10-fold greater than those cultured in vitro.

Pneumococcal meningitis and endocarditis in an infant: possible improved survival with factor V Leiden mutation.

PubMed

Mohapatra, Sitikant; Doulah, Assaf; Brown, Elspeth

2017-10-01

Streptococcus pneumoniae infections continue to remain associated with high morbidity and mortality. Although the incidence of invasive meningeal and/or lung disease are not uncommon, Streptococcus pneumoniae endocarditis is rare especially in healthy pediatric population. New studies have suggested a strong association between factor V leiden (FVL) mutation and favorable outcomes in critically ill children. A healthy 10 month old presented with sepsis and meningeal signs, was later confirmed to have Streptococcus pneumoniae meningitis and endocarditis. She was found to have factor V leiden mutation and made a complete recovery despite initial complications. Presence of factor V leiden mutation in critically ill children with severe septicaemia possibly contributes to better outcomes. What is known: • Mortality and morbidity remain high with invasive pneumococcal disease. • Pneumococcal endocarditis is rare in healthy pediatric population and results in significant morbidity and mortality What is new: • New studies have suggested a strong association between factor V leiden (FVL) mutation and favorable outcomes in critically ill children. • The presence of factor V mutation in children with extensive invasive pneumococcal disease possibly contributes to a better outcome.

Recombinant expression of Streptococcus pneumoniae capsular polysaccharides in Escherichia coli

PubMed Central

Kay, Emily J.; Yates, Laura E.; Terra, Vanessa S.; Cuccui, Jon; Wren, Brendan W.

2016-01-01

Currently, Streptococcus pneumoniae is responsible for over 14 million cases of pneumonia worldwide annually, and over 1 million deaths, the majority of them children. The major determinant for pathogenesis is a polysaccharide capsule that is variable and is used to distinguish strains based on their serotype. The capsule forms the basis of the pneumococcal polysaccharide vaccine (PPV23) that contains purified capsular polysaccharide from 23 serotypes, and the pneumococcal conjugate vaccine (PCV13), containing 13 common serotypes conjugated to CRM197 (mutant diphtheria toxin). Purified capsule from S. pneumoniae is required for pneumococcal conjugate vaccine production, and costs can be prohibitively high, limiting accessibility of the vaccine in low-income countries. In this study, we demonstrate the recombinant expression of the capsule-encoding locus from four different serotypes of S. pneumoniae within Escherichia coli. Furthermore, we attempt to identify the minimum set of genes necessary to reliably and efficiently express these capsules heterologously. These E. coli strains could be used to produce a supply of S. pneumoniae serotype-specific capsules without the need to culture pathogenic bacteria. Additionally, these strains could be applied to synthetic glycobiological applications: recombinant vaccine production using E. coli outer membrane vesicles or coupling to proteins using protein glycan coupling technology. PMID:27110302

Nonencapsulated Streptococcus pneumoniae causes otitis media during single-species infection and during polymicrobial infection with nontypeable Haemophilus influenzae.

PubMed

Murrah, Kyle A; Pang, Bing; Richardson, Stephen; Perez, Antonia; Reimche, Jennifer; King, Lauren; Wren, John; Swords, W Edward

2015-07-01

Streptococcus pneumoniae strains lacking capsular polysaccharide have been increasingly reported in carriage and disease contexts. Since most cases of otitis media involve more than one bacterial species, we aimed to determine the capacity of a nonencapsulated S. pneumoniae clinical isolate to induce disease in the context of a single-species infection and as a polymicrobial infection with nontypeable Haemophilus influenzae. Using the chinchilla model of otitis media, we found that nonencapsulated S. pneumoniae colonizes the nasopharynx following intranasal inoculation, but does not readily ascend into the middle ear. However, when we inoculated nonencapsulated S. pneumoniae directly into the middle ear, the bacteria persisted for two weeks post-inoculation and induced symptoms consistent with chronic otitis media. During coinfection with nontypeable H. influenzae, both species persisted for one week and induced polymicrobial otitis media. We also observed that nontypeable H. influenzae conferred passive protection from killing by amoxicillin upon S. pneumoniae from within polymicrobial biofilms in vitro. Therefore, based on these results, we conclude that nonencapsulated pneumococci are a potential causative agent of chronic/recurrent otitis media, and can also cause mutualistic infection with other opportunists, which could complicate treatment outcomes. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Host Glycan Sugar-Specific Pathways in Streptococcus pneumonia: Galactose as a Key Sugar in Colonisation and Infection

PubMed Central

Paixão, Laura; Oliveira, Joana; Veríssimo, André; Vinga, Susana; Lourenço, Eva C.; Ventura, M. Rita; Kjos, Morten; Veening, Jan-Willem; Fernandes, Vitor E.; Andrew, Peter W.; Yesilkaya, Hasan; Neves, Ana Rute

2015-01-01

The human pathogen Streptococcus pneumoniae is a strictly fermentative organism that relies on glycolytic metabolism to obtain energy. In the human nasopharynx S. pneumoniae encounters glycoconjugates composed of a variety of monosaccharides, which can potentially be used as nutrients once depolymerized by glycosidases. Therefore, it is reasonable to hypothesise that the pneumococcus would rely on these glycan-derived sugars to grow. Here, we identified the sugar-specific catabolic pathways used by S. pneumoniae during growth on mucin. Transcriptome analysis of cells grown on mucin showed specific upregulation of genes likely to be involved in deglycosylation, transport and catabolism of galactose, mannose and N acetylglucosamine. In contrast to growth on mannose and N-acetylglucosamine, S. pneumoniae grown on galactose re-route their metabolic pathway from homolactic fermentation to a truly mixed acid fermentation regime. By measuring intracellular metabolites, enzymatic activities and mutant analysis, we provide an accurate map of the biochemical pathways for galactose, mannose and N-acetylglucosamine catabolism in S. pneumoniae. Intranasal mouse infection models of pneumococcal colonisation and disease showed that only mutants in galactose catabolic genes were attenuated. Our data pinpoint galactose as a key nutrient for growth in the respiratory tract and highlights the importance of central carbon metabolism for pneumococcal pathogenesis. PMID:25826206

Antibiotic Susceptibility Patterns of Bacterial Isolates from Pus Samples in a Tertiary Care Hospital of Punjab, India

PubMed Central

Trojan, Rugira; Razdan, Lovely

2016-01-01

We determined the prevalence and antibiotic susceptibilities patterns of bacterial isolates from pus samples collected from patients in a tertiary care hospital of Punjab, India. E. coli was the most prevalent pathogen (51.2%) followed by Staphylococcus aureus (21%), Klebsiella pneumoniae (11.6%), Pseudomonas aeruginosa (5.8%), Citrobacter spp. (3.5%), Acinetobacter baumannii (2.3%), Proteus mirabilis (2.3%), and Streptococcus spp. (2.3%). E. coli, K. pneumoniae, A. baumannii, and Citrobacter isolates were resistant to multiple antibiotics including higher generation cephalosporins. S. aureus and Streptococcus isolates were sensitive to cloxacillin and vancomycin. However, P. aeruginosa, P. mirabilis, and Streptococcus isolates were found to be less resistant to the spectrum of antibiotics tested. Overall, our findings indicate the prevalence of resistance to different classes of antibiotics in bacterial isolates from pus infections and hence highlight the need for effective surveillance, regulator reporting, and antibiogram-guided antibiotic prescription. PMID:27872643

Antibiotic Susceptibility Patterns of Bacterial Isolates from Pus Samples in a Tertiary Care Hospital of Punjab, India.

PubMed

Trojan, Rugira; Razdan, Lovely; Singh, Nasib

2016-01-01

We determined the prevalence and antibiotic susceptibilities patterns of bacterial isolates from pus samples collected from patients in a tertiary care hospital of Punjab, India. E. coli was the most prevalent pathogen (51.2%) followed by Staphylococcus aureus (21%), Klebsiella pneumoniae (11.6%), Pseudomonas aeruginosa (5.8%), Citrobacte r spp. (3.5%), Acinetobacter baumannii (2.3%), Proteus mirabilis (2.3%), and Streptococcus spp. (2.3%). E. coli , K. pneumoniae , A. baumannii , and Citrobacter isolates were resistant to multiple antibiotics including higher generation cephalosporins. S. aureus and Streptococcus isolates were sensitive to cloxacillin and vancomycin. However, P. aeruginosa , P. mirabilis , and Streptococcus isolates were found to be less resistant to the spectrum of antibiotics tested. Overall, our findings indicate the prevalence of resistance to different classes of antibiotics in bacterial isolates from pus infections and hence highlight the need for effective surveillance, regulator reporting, and antibiogram-guided antibiotic prescription.

The novel species Streptococcus tigurinus and its association with oral infection

PubMed Central

Zbinden, Andrea; Bostanci, Nagihan; Belibasakis, Georgios N

2015-01-01

Streptococcus tigurinus is a novel species of viridans streptococci, shown to cause severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. S. tigurinus belongs to the Streptococcus mitis group and is most closely related to Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae and Streptococcus infantis. The presence of S. tigurinus in the human oral cavity has been documented, including in patients with periodontal disease. This review addresses the available scientific knowledge on S. tigurinus and its association with closely related streptococci, and discusses its putative involvement in common oral infections. While there is as yet no strong evidence on the involvement of S. tigurinus with oral infections, its presence in the oral cavity and its association with endocarditis warrants special attention for a link between oral and systemic infection. PMID:25483862

Peritonitis in a llama caused by Streptococcus equi subsp. zooepidemicus.

PubMed Central

Hewson, J; Cebra, C K

2001-01-01

A 7-month-old, male llama was diagnosed with peritonitis caused by Streptococcus equi subsp. zooepidemicus. Clinical findings, medical treatment, and case outcome are described. Hematogenous dissemination from suspected pneumonia is proposed as the route of infection in this case. Possible transmission of the organism through contact with horses is discussed. PMID:11424579

The Streptococcus sanguinis competence regulon is not required for infective endocarditis virulence in a rabbit model.

PubMed

Callahan, Jill E; Munro, Cindy L; Kitten, Todd

2011-01-01

Streptococcus sanguinis is an important component of dental plaque and a leading cause of infective endocarditis. Genetic competence in S. sanguinis requires a quorum sensing system encoded by the early comCDE genes, as well as late genes controlled by the alternative sigma factor, ComX. Previous studies of Streptococcus pneumoniae and Streptococcus mutans have identified functions for the >100-gene com regulon in addition to DNA uptake, including virulence. We investigated this possibility in S. sanguinis. Strains deleted for the comCDE or comX master regulatory genes were created. Using a rabbit endocarditis model in conjunction with a variety of virulence assays, we determined that both mutants possessed infectivity equivalent to that of a virulent control strain, and that measures of disease were similar in rabbits infected with each strain. These results suggest that the com regulon is not required for S. sanguinis infective endocarditis virulence in this model. We propose that the different roles of the S. sanguinis, S. pneumoniae, and S. mutans com regulons in virulence can be understood in relation to the pathogenic mechanisms employed by each species.

Recombination in Streptococcus pneumoniae Lineages Increase with Carriage Duration and Size of the Polysaccharide Capsule

PubMed Central

Andam, Cheryl P.; Harris, Simon R.; Cornick, Jennifer E.; Yang, Marie; Bricio-Moreno, Laura; Kamng’ona, Arox W.; French, Neil; Heyderman, Robert S.; Kadioglu, Aras; Everett, Dean B.; Bentley, Stephen D.

2016-01-01

ABSTRACT Streptococcus pneumoniae causes a high burden of invasive pneumococcal disease (IPD) globally, especially in children from resource-poor settings. Like many bacteria, the pneumococcus can import DNA from other strains or even species by transformation and homologous recombination, which has allowed the pneumococcus to evade clinical interventions such as antibiotics and pneumococcal conjugate vaccines (PCVs). Pneumococci are enclosed in a complex polysaccharide capsule that determines the serotype; the capsule varies in size and is associated with properties including carriage prevalence and virulence. We determined and quantified the association between capsule and recombination events using genomic data from a diverse collection of serotypes sampled in Malawi. We determined both the amount of variation introduced by recombination relative to mutation (the relative rate) and how many individual recombination events occur per isolate (the frequency). Using univariate analyses, we found an association between both recombination measures and multiple factors associated with the capsule, including duration and prevalence of carriage. Because many capsular factors are correlated, we used multivariate analysis to correct for collinearity. Capsule size and carriage duration remained positively associated with recombination, although with a reduced P value, and this effect may be mediated through some unassayed additional property associated with larger capsules. This work describes an important impact of serotype on recombination that has been previously overlooked. While the details of how this effect is achieved remain to be determined, it may have important consequences for the serotype-specific response to vaccines and other interventions. PMID:27677790

Both Influenza-Induced Neutrophil Dysfunction and Neutrophil-Independent Mechanisms Contribute to Increased Susceptibility to a Secondary Streptococcus pneumoniae Infection▿

PubMed Central

McNamee, Lynnelle A.; Harmsen, Allen G.

2006-01-01

Since secondary Streptococcus pneumoniae infections greatly increase the mortality of influenza infections, we determined the relative roles of neutrophil-dependent and -independent mechanisms in increased susceptibility to S. pneumoniae during influenza infection. Mice infected with influenza for 6 days, but not 3 days, showed a significant increase in susceptibility to S. pneumoniae infection compared to mice not infected with influenza. There was significant neutrophil accumulation in the lungs of S. pneumoniae-infected mice regardless of whether or not they were infected with influenza for 3 or 6 days. Depletion of neutrophils in these mice resulted in increased susceptibility to S. pneumoniae in both the non-influenza-infected mice and mice infected with influenza for 3 days but not in the mice infected with influenza for 6 days, indicating that a prior influenza infection of 6 days may compromise neutrophil function, resulting in increased susceptibility to a S. pneumoniae infection. Neutrophils from the lungs of mice infected with influenza for 3 or 6 days exhibited functional impairment in the form of decreased phagocytosis and intracellular reactive oxygen species generation in response to S. pneumoniae. In addition, neutrophil-depleted mice infected with influenza for 6 days were more susceptible to S. pneumoniae than neutrophil-depleted mice not infected with influenza, indicating that neutrophil-independent mechanisms also contribute to influenza-induced increased susceptibility to S. pneumoniae. Pulmonary interleukin-10 levels were increased in coinfected mice infected with influenza for 6 days but not 3 days. Thus, an influenza infection of 6 days increases susceptibility to S. pneumoniae by both suppression of neutrophil function and by neutrophil-independent mechanisms such as enhanced cytokine production. PMID:16982840

Virome and bacteriome characterization of children with pneumonia and asthma in Mexico City during winter seasons 2014 and 2015

PubMed Central

Romero-Espinoza, Jose A.; Moreno-Valencia, Yazmin; Coronel-Tellez, Rodrigo H.; Castillejos-Lopez, Manuel; Hernandez, Andres; Dominguez, Aaron; Miliar-Garcia, Angel; Barbachano-Guerrero, Arturo; Perez-Padilla, Rogelio; Alejandre-Garcia, Alejandro

2018-01-01

Background Acute asthma exacerbations and pneumonia are important causes of morbidity and mortality in children and may coexist in the same children, although symptom overlap may lead to difficulties in diagnosis. Microbial and viral diversity and differential abundance of either may play an important role in infection susceptibility and the development of acute and chronic respiratory diseases. Objectives To describe the virome and bacteriome present in the upper respiratory tract of hospitalized children with a clinical diagnosis of asthma and pneumonia during an acute exacerbation and an acute respiratory illness ARI episode respectively. Methods During the winter seasons of 2013–2014 and 2014–2015, 134 nasopharyngeal swabs samples of children <15 years of age with ARI hospitalized at a referral hospital for respiratory diseases were selected based on clinical diagnosis of asthma or pneumonia. The virome and bacteriome were characterized using Whole Genome Sequencing (WGS) and in-house bioinformatics analysis pipeline. Results The Asthma group was represented mainly by RV-C, BoV-1 and RSV-B and the pneumonia group by Bacteriophage EJ-1 and TTMV. TTV was found in both groups with a similar amount of reads. About bacterial composition Moraxella catarrhalis, Propionibacterium acnes and Acinetobacter were present in asthma and Veillonella parvula and Mycoplasma pneumoniae in pneumonia. Streptococcus pneumoniae and Haemophilus influenzae were mostly found with both asthma and pneumonia. Conclusions Our results show a complex viral and bacterial composition in asthma and pneumonia groups with a strong association of RV-C presence in asthmatic children. We observed Streptococcus pneumoniae and Haemophilus influenzae concurrently in both groups. PMID:29447223

Improved Differentiation of Streptococcus pneumoniae and Other S. mitis Group Streptococci by MALDI Biotyper Using an Improved MALDI Biotyper Database Content and a Novel Result Interpretation Algorithm.

PubMed

Harju, Inka; Lange, Christoph; Kostrzewa, Markus; Maier, Thomas; Rantakokko-Jalava, Kaisu; Haanperä, Marjo

2017-03-01

Reliable distinction of Streptococcus pneumoniae and viridans group streptococci is important because of the different pathogenic properties of these organisms. Differentiation between S. pneumoniae and closely related Sreptococcus mitis species group streptococci has always been challenging, even when using such modern methods as 16S rRNA gene sequencing or matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. In this study, a novel algorithm combined with an enhanced database was evaluated for differentiation between S. pneumoniae and S. mitis species group streptococci. One hundred one clinical S. mitis species group streptococcal strains and 188 clinical S. pneumoniae strains were identified by both the standard MALDI Biotyper database alone and that combined with a novel algorithm. The database update from 4,613 strains to 5,627 strains drastically improved the differentiation of S. pneumoniae and S. mitis species group streptococci: when the new database version containing 5,627 strains was used, only one of the 101 S. mitis species group isolates was misidentified as S. pneumoniae , whereas 66 of them were misidentified as S. pneumoniae when the earlier 4,613-strain MALDI Biotyper database version was used. The updated MALDI Biotyper database combined with the novel algorithm showed even better performance, producing no misidentifications of the S. mitis species group strains as S. pneumoniae All S. pneumoniae strains were correctly identified as S. pneumoniae with both the standard MALDI Biotyper database and the standard MALDI Biotyper database combined with the novel algorithm. This new algorithm thus enables reliable differentiation between pneumococci and other S. mitis species group streptococci with the MALDI Biotyper. Copyright © 2017 American Society for Microbiology.

The Protein Interactome of Streptococcus pneumoniae and Bacterial Meta-interactomes Improve Function Predictions.

PubMed

Wuchty, S; Rajagopala, S V; Blazie, S M; Parrish, J R; Khuri, S; Finley, R L; Uetz, P

2017-01-01

The functions of roughly a third of all proteins in Streptococcus pneumoniae , a significant human-pathogenic bacterium, are unknown. Using a yeast two-hybrid approach, we have determined more than 2,000 novel protein interactions in this organism. We augmented this network with meta-interactome data that we defined as the pool of all interactions between evolutionarily conserved proteins in other bacteria. We found that such interactions significantly improved our ability to predict a protein's function, allowing us to provide functional predictions for 299 S. pneumoniae proteins with previously unknown functions. IMPORTANCE Identification of protein interactions in bacterial species can help define the individual roles that proteins play in cellular pathways and pathogenesis. Very few protein interactions have been identified for the important human pathogen S. pneumoniae . We used an experimental approach to identify over 2,000 new protein interactions for S. pneumoniae , the most extensive interactome data for this bacterium to date. To predict protein function, we used our interactome data augmented with interactions from other closely related bacteria. The combination of the experimental data and meta-interactome data significantly improved the prediction results, allowing us to assign possible functions to a large number of poorly characterized proteins.

Pneumococcal Disease: Diagnosis and Treatment

MedlinePlus

... Vaccination For Clinicians Streptococcus pneumoniae Transmission Clinical Features Risk Factors Diagnosis & Management Prevention For Laboratorians Drug Resistance Surveillance & Reporting Global ...

Pneumococcal Disease: Types of Infection

MedlinePlus

... Vaccination For Clinicians Streptococcus pneumoniae Transmission Clinical Features Risk Factors Diagnosis & Management Prevention For Laboratorians Drug Resistance Surveillance & Reporting Global ...

Pneumococcal Disease: Symptoms and Complications

MedlinePlus

... Vaccination For Clinicians Streptococcus pneumoniae Transmission Clinical Features Risk Factors Diagnosis & Management Prevention For Laboratorians Drug Resistance Surveillance & Reporting Global ...

Infection by Streptococcus pneumoniae in children with or without radiologically confirmed pneumonia.

PubMed

Andrade, Dafne C; Borges, Igor C; Vilas-Boas, Ana Luísa; Fontoura, Maria S H; Araújo-Neto, César A; Andrade, Sandra C; Brim, Rosa V; Meinke, Andreas; Barral, Aldina; Ruuskanen, Olli; Käyhty, Helena; Nascimento-Carvalho, Cristiana M

Community-acquired pneumonia is an important cause of morbidity in childhood, but the detection of its causative agent remains a diagnostic challenge. The authors aimed to evaluate the role of the chest radiograph to identify cases of community-aquired pneumonia caused by typical bacteria. The frequency of infection by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis was compared in non-hospitalized children with clinical diagnosis of community acquired pneumonia aged 2-59 months with or without radiological confirmation (n=249 and 366, respectively). Infection by S. pneumoniae was diagnosed by the detection of a serological response against at least one of eight pneumococcal proteins (defined as an increase ≥2-fold in the IgG levels against Ply, CbpA, PspA1 and PspA2, PhtD, StkP-C, and PcsB-N, or an increase ≥1.5-fold against PcpA). Infection by H. influenzae and M. catarrhalis was defined as an increase ≥2-fold on the levels of microbe-specific IgG. Children with radiologically confirmed pneumonia had higher rates of infection by S. pneumoniae. The presence of pneumococcal infection increased the odds of having radiologically confirmed pneumonia by 2.8 times (95% CI: 1.8-4.3). The negative predictive value of the normal chest radiograph for infection by S. pneumoniae was 86.3% (95% CI: 82.4-89.7%). There was no difference on the rates of infection by H. influenzae and M. catarrhalis between children with community-acquired pneumonia with and without radiological confirmation. Among children with clinical diagnosis of community-acquired pneumonia submitted to chest radiograph, those with radiologically confirmed pneumonia present a higher rate of infection by S. pneumoniae when compared with those with a normal chest radiograph. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates from adult patients in Jakarta, Indonesia.

PubMed

Said, Wahyu F; Sukoto, Edy; Khoeri, Miftahuddin M; Kumalawati, July; Safari, Dodi

Currently, the data on pneumococcal invasive disease in the Indonesian population are limited. In this study, we investigated the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae. These samples were isolated from the sputum of adult patients with non-specific clinical symptoms aged 18-87 years in Jakarta, Indonesia, from August to October 2014. Of the 349 sputum specimens, thirteen isolates were identified as S. pneumoniae strains (4%), with two strains each for serotype 19F, 3, and 15A, and one strain each for serotype/serogroup 13, 23A, 6, 34, 17F, 16F, and untypeable. Resistance to tetracycline was most common with only 5 of 13 strains being susceptible. In conclusion, these data provide an initial in the surveillance of invasive pneumococcus in the Indonesia population. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Novel surface attachment mechanism of the Streptococcus pneumoniae protein PspA.

PubMed Central

Yother, J; White, J M

1994-01-01

Pneumococcal surface protein A (PspA) of Streptococcus pneumoniae has been found to utilize a novel mechanism for anchoring to the bacterial cell surface. In contrast to that of surface proteins from other gram-positive bacteria, PspA anchoring required choline-mediated interactions between the membrane-associated lipoteichoic acid and the C-terminal repeat region of PspA. Release of PspA from the cell surface could be effected by deletion of 5 of the 10 C-terminal repeat units, by high concentrations of choline, or by growth in choline-deficient medium. Other pneumococcal proteins, including autolysin, which has a similar C-terminal repeat region, were not released by these treatments. The attachment mechanism utilized by PspA thus appears to be uniquely adapted to exploit the unusual structure of the pneumococcal cell surface. Further, it has provided the means for rapid and simple isolation of immunogenic PspA from S. pneumoniae. Images PMID:7910604

Evaluation of Streptococcus pneumoniae in bile samples: A case series review.

PubMed

Itoh, Naoya; Kawamura, Ichiro; Tsukahara, Mika; Mori, Keita; Kurai, Hanako

2016-06-01

Although Streptococcus pneumoniae is an important pathogen of humans, pneumococcal cholangitis is rare because of the rapid autolysis of S. pneumoniae. The aim of this case series was to review patients with bile cultures positive for S. pneumoniae. This study was a single center retrospective case series review of patients with S. pneumoniae in their bile at a tertiary-care cancer center between September 2002 and August 2015. Subjects consisted of all patients in whom S. pneumoniae was isolated in their bile during the study period. Bile specimens for culture were obtained from biliary drainage procedures such as endoscopic retrograde biliary drainage, endoscopic nasobiliary drainage, and percutaneous transhepatic biliary drainage. There were 20 patients with bile cultures positive for S. pneumoniae during the study period. All patients presented with extrahepatic obstructive jaundice due to hepatopancreatobiliary tumors. Nineteen of 20 patients underwent the placement of plastic intrabiliary tubes. The mean time between the first-time drainage and the positive culture was 26 days (range 0-313 days). Although 12 of 20 patients met our definition of cholangitis, 5 were clinically treated with antibiotics based on a physician's assessment of whether there was a true infection. The present study is the largest case series of patients with S. pneumoniae in their bile. Based on our findings, the isolation of S. pneumoniae from bile may be attributed to the placement of biliary drainage devices. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

The novel conjugative transposon tn1207.3 carries the macrolide efflux gene mef(A) in Streptococcus pyogenes.

PubMed

Santagati, Maria; Iannelli, Francesco; Cascone, Carmela; Campanile, Floriana; Oggioni, Marco R; Stefani, Stefania; Pozzi, Gianni

2003-01-01

The macrolide efflux gene mef(A) of the Streptococcus pyogenes clinical strain 2812A was found to be carried by a 52-kb chromosomal genetic element that could be transferred by conjugation to the chromosome of other streptococcal species. The characteristics of this genetic element are typical of conjugative transposons and was named Tn1207.3. The size of Tn1207.3 was established by pulsed-field gel electrophoresis (PFGE), and DNA sequencing analysis showed that the 7,244 bp at the left end of Tn1207.3 were identical to those of the pneumococcal Tn1207.1 element. Tn1207.3-like genetic elements were found to be inserted at a single specific chromosomal site in 12 different clinical isolates S. pyogenes exhibiting the M phenotype of resistance to macrolides and carrying the mef(A) gene. Tn1207.3 was transferred from S. pyogenes 2812A to Streptococcus pneumoniae, and sequence analysis carried out on six independent transconjugants showed that insertion of Tn1207.3 in the pneumococcal genome always occurred at a single specific site as in Tn1207.1. Using MF2, a representative S. pneumoniae transconjugant, as a donor, Tn1207.3 was transferred again by conjugation to S. pyogenes and Streptococcus gordonii. The previously described nonconjugative element Tn1207.1 of S. pneumoniae appears to be a defective element, part of a longer conjugative transposon that carries mef(A) and is found in clinical isolates of S. pyogenes.

Pneumococcal Disease: Risk Factors and Transmission

MedlinePlus

... Vaccination For Clinicians Streptococcus pneumoniae Transmission Clinical Features Risk Factors Diagnosis & Management Prevention For Laboratorians Drug Resistance Surveillance & Reporting Global ...

The Impact of Order Set Use on Pneumococcal Vaccination at the Time of Admission and at the Time of Discharge for Adult Patients in an Acute Inpatient Setting

ERIC Educational Resources Information Center

Mathew, Rekha

2012-01-01

Background: Pneumococcal vaccination (PV) is important as Streptococcus pneumoniae accounts for one third of all hospitalizations for community-acquired pneumonia. In 2009, 1.1 million people in the U.S. were hospitalized with pneumonia and more than 50,000 people died from the disease. The Centers for Disease Control and Prevention recommend that…

Empyema necessitans in a six-month-old girl.

PubMed

Goussard, P; Gie, Robert; Janson, Jacques; Andronikou, Savvas

2018-05-23

Empyema necessitans is a rare complication of acute bacterial pneumonia, especially in children. It is a complication of empyema characterised by the extension of pus from the pleural cavity into the thoracic wall to form a mass of purulent fluid in the adjacent soft tissue. An inflammatory chest wall mass following pneumonia caused by Streptococcus pneumonia in a six-month-old infant is reported. The case emphasises that children presenting with persistent fever and a painful chest wall mass following pneumonia should be investigated immediately as there might be an urgent need for surgery.

Quantitative Detection of Streptococcus pneumoniae in Nasopharyngeal Secretions by Real-Time PCR

PubMed Central

Greiner, Oliver; Day, Philip J. R.; Bosshard, Philipp P.; Imeri, Fatime; Altwegg, Martin; Nadal, David

2001-01-01

Streptococcus pneumoniae is an important cause of community-acquired pneumonia. However, in this setting the diagnostic sensitivity of blood cultures is below 30%. Since during such infections changes in the amounts of S. pneumoniae may also occur in the upper respiratory tract, quantification of these bacteria in nasopharnygeal secretions (NPSs) may offer a suitable diagnostic approach. Real-time PCR offers a sensitive, efficient, and routinely reproducible approach to quantification. Using primers and a fluorescent probe specific for the pneumolysin gene, we were able to detect DNA from serial dilutions of S. pneumoniae cells in which the quantities of DNA ranged from the amounts extracted from 1 to 106 cells. No difference was noted when the same DNA was mixed with DNA extracted from NPSs shown to be deficient of S. pneumoniae following culture, suggesting that this bacterium can be detected and accurately quantitated in clinical samples. DNAs from Haemophilus influenzae, Moraxella catarrhalis, or alpha-hemolytic streptococci other than S. pneumoniae were not amplified or were only weakly amplified when there were ≥106 cells per reaction mixture. When the assay was applied to NPSs from patients with respiratory tract infections, the assay performed with a sensitivity of 100% and a specificity of up to 96% compared to the culture results. The numbers of S. pneumoniae organisms detected by real-time PCR correlated with the numbers detected by semiquantitative cultures. A real-time PCR that targeted the pneumolysin gene provided a sensitive and reliable means for routine rapid detection and quantification of S. pneumoniae present in NPSs. This assay may serve as a tool to study changes in the amounts of S. pneumoniae during lower respiratory tract infections. PMID:11526140

Dynamic distribution of the SecA and SecY translocase subunits and septal localization of the HtrA surface chaperone/protease during Streptococcus pneumoniae D39 cell division.

PubMed

Tsui, Ho-Ching Tiffany; Keen, Susan K; Sham, Lok-To; Wayne, Kyle J; Winkler, Malcolm E

2011-01-01

The Sec translocase pathway is the major route for protein transport across and into the cytoplasmic membrane of bacteria. Previous studies reported that the SecA translocase ATP-binding subunit and the cell surface HtrA protease/chaperone formed a single microdomain, termed "ExPortal," in some species of ellipsoidal (ovococcus) Gram-positive bacteria, including Streptococcus pyogenes. To investigate the generality of microdomain formation, we determined the distribution of SecA and SecY by immunofluorescent microscopy in Streptococcus pneumoniae (pneumococcus), which is an ovococcus species evolutionarily distant from S. pyogenes. In the majority (≥ 75%) of exponentially growing cells, S. pneumoniae SecA (SecA (Spn)) and SecY (Spn) located dynamically in cells at different stages of division. In early divisional cells, both Sec subunits concentrated at equators, which are future sites of constriction. Further along in division, SecA(Spn) and SecY(Spn) remained localized at mid-cell septa. In late divisional cells, both Sec subunits were hemispherically distributed in the regions between septa and the future equators of dividing cells. In contrast, the HtrA (Spn) homologue localized to the equators and septa of most (> 90%) dividing cells, whereas the SrtA(Spn) sortase located over the surface of cells in no discernable pattern. This dynamic pattern of Sec distribution was not perturbed by the absence of flotillin family proteins, but was largely absent in most cells in early stationary phase and in cls mutants lacking cardiolipin synthase. These results do not support the existence of an ExPortal microdomain in S. pneumoniae. Instead, the localization of the pneumococcal Sec translocase depends on the stage of cell division and anionic phospholipid content. Two patterns of Sec translocase distribution, an ExPortal microdomain in certain ovococcus-shaped species like Streptococcus pyogenes and a spiral pattern in rod-shaped species like Bacillus subtilis, have been reported for Gram-positive bacteria. This study provides evidence for a third pattern of Sec localization in the ovococcus human pathogen Streptococcus pneumoniae. The SecA motor and SecY channel subunits of the Sec translocase localize dynamically to different places in the mid-cell region during the division cycle of exponentially growing, but not stationary-phase, S. pneumoniae. Unexpectedly, the S. pneumoniae HtrA (HtrA(Spn)) protease/chaperone principally localizes to cell equators and division septa. The coincident localization of SecA(Spn), SecY (Spn), and HtrA (Spn) to regions of peptidoglycan (PG) biosynthesis in unstressed, growing cells suggests that the pneumococcal Sec translocase directs assembly of the PG biosynthesis apparatus to regions where it is needed during division and that HtrA(Spn) may play a general role in quality control of proteins exported by the Sec translocase.

[Community-acquired pneumonia--from medical technologist].

PubMed

Yamanaka, Kiyoharu

2002-07-01

The main causative microorganisms of Community-acquired pneumonia are Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus. Especially the causative microorganisms affecting whole body basic disease, persons of advanced age, and alcoholic patients are Moraxella catarrhalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida spp., Cryptococcus spp., Aspergillus spp., Pneumocystis carinii and anaerobic bacteria. Other microorganisms involved in epidemic disease, action condition (travel around hot springs etc.) and pet breeding environments are Mycoplasma pneumoniae, Legionella pnumophila, Chlamydia spp., respiratory syncytial virus, influenza virus, and adeno virus. We suggest methods of advancing the microscopic and microbiological examination and report, and quickly obtaining clinical information and extracting the clinical specimen. We also describe the inspection method for a case "Legionella pneumonia" that was discussed during this symposium.

Ethanol-induced alcohol dehydrogenase E (AdhE) potentiates pneumolysin in Streptococcus pneumoniae.

PubMed

Luong, Truc Thanh; Kim, Eun-Hye; Bak, Jong Phil; Nguyen, Cuong Thach; Choi, Sangdun; Briles, David E; Pyo, Suhkneung; Rhee, Dong-Kwon

2015-01-01

Alcohol impairs the host immune system, rendering the host more vulnerable to infection. Therefore, alcoholics are at increased risk of acquiring serious bacterial infections caused by Streptococcus pneumoniae, including pneumonia. Nevertheless, how alcohol affects pneumococcal virulence remains unclear. Here, we showed that the S. pneumoniae type 2 D39 strain is ethanol tolerant and that alcohol upregulates alcohol dehydrogenase E (AdhE) and potentiates pneumolysin (Ply). Hemolytic activity, colonization, and virulence of S. pneumoniae, as well as host cell myeloperoxidase activity, proinflammatory cytokine secretion, and inflammation, were significantly attenuated in adhE mutant bacteria (ΔadhE strain) compared to D39 wild-type bacteria. Therefore, AdhE might act as a pneumococcal virulence factor. Moreover, in the presence of ethanol, S. pneumoniae AdhE produced acetaldehyde and NADH, which subsequently led Rex (redox-sensing transcriptional repressor) to dissociate from the adhE promoter. An increase in AdhE level under the ethanol condition conferred an increase in Ply and H2O2 levels. Consistently, S. pneumoniae D39 caused higher cytotoxicity to RAW 264.7 cells than the ΔadhE strain under the ethanol stress condition, and ethanol-fed mice (alcoholic mice) were more susceptible to infection with the D39 wild-type bacteria than with the ΔadhE strain. Taken together, these data indicate that AdhE increases Ply under the ethanol stress condition, thus potentiating pneumococcal virulence. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Pneumolysin-Dependent Calpain Activation and Interleukin-1α Secretion in Macrophages Infected with Streptococcus pneumoniae.

PubMed

Fang, Rendong; Wu, Rui; Du, Huihui; Jin, Meilan; Liu, Yajing; Lei, Guihua; Jiang, Bing; Lei, Zehui; Peng, Yuanyi; Nie, Kui; Tsuchiya, Kohsuke

2017-09-01

Pneumolysin (PLY), a major virulence factor of Streptococcus pneumoniae , is a pore-forming cytolysin that modulates host innate responses contributing to host defense against and pathogenesis of pneumococcal infections. Interleukin-1α (IL-1α) has been shown to be involved in tissue damage in a pneumococcal pneumonia model; however, the mechanism by which this cytokine is produced during S. pneumoniae infection remains unclear. In this study, we examined the role of PLY in IL-1α production. Although the strains induced similar levels of pro-IL-1α expression, wild-type S. pneumoniae D39, but not a deletion mutant of the ply gene (Δ ply ), induced the secretion of mature IL-1α from host macrophages, suggesting that PLY is critical for the maturation and secretion of IL-1α during S. pneumoniae infection. Further experiments with calcium chelators and calpain inhibitors indicated that extracellular calcium ions and calpains (calcium-dependent proteases) facilitated the maturation and secretion of IL-1α from D39-infected macrophages. Moreover, we found that PLY plays a critical role in calcium influx and calpain activation, as elevated intracellular calcium levels and the degradation of the calpain substrate α-fodrin were detected in macrophages infected with D39 but not the Δ ply strain. These results suggested that PLY induces the influx of calcium in S. pneumoniae -infected macrophages, followed by calpain activation and subsequent IL-1α maturation and secretion. Copyright © 2017 American Society for Microbiology.

Evaluation of the BinaxNOW® Streptococcus pneumoniae antigen test on fresh, frozen and concentrated urine samples in elderly patients with and without community-acquired pneumonia.

PubMed

Saukkoriipi, Annika; Pascal, Thierry; Palmu, Arto A

2016-02-01

We evaluated the BinaxNOW® urine antigen test in elderly. For fresh un-concentrated urine samples, the sensitivity for pneumococcal pneumonia was 63% and specificity 97%. After freezing and concentration, the results comparable to positive control line in intensity at 60 min gave high sensitivity (81%) with no loss in specificity (96%). Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of 88 regulatory small RNAs in the TIGR4 strain of the human pathogen Streptococcus pneumoniae

PubMed Central

Acebo, Paloma; Martin-Galiano, Antonio J.; Navarro, Sara; Zaballos, Ángel; Amblar, Mónica

2012-01-01

Streptococcus pneumoniae is the main etiological agent of community-acquired pneumonia and a major cause of mortality and morbidity among children and the elderly. Genome sequencing of several pneumococcal strains revealed valuable information about the potential proteins and genetic diversity of this prevalent human pathogen. However, little is known about its transcriptional regulation and its small regulatory noncoding RNAs. In this study, we performed deep sequencing of the S. pneumoniae TIGR4 strain RNome to identify small regulatory RNA candidates expressed in this pathogen. We discovered 1047 potential small RNAs including intragenic, 5′- and/or 3′-overlapping RNAs and 88 small RNAs encoded in intergenic regions. With this approach, we recovered many of the previously identified intergenic small RNAs and identified 68 novel candidates, most of which are conserved in both sequence and genomic context in other S. pneumoniae strains. We confirmed the independent expression of 17 intergenic small RNAs and predicted putative mRNA targets for six of them using bioinformatics tools. Preliminary results suggest that one of these six is a key player in the regulation of competence development. This study is the biggest catalog of small noncoding RNAs reported to date in S. pneumoniae and provides a highly complete view of the small RNA network in this pathogen. PMID:22274957

Flomoxef showed excellent in vitro activity against clinically important gram-positive and gram-negative pathogens causing community- and hospital-associated infections.

PubMed

Yang, Qiwen; Zhang, Hui; Cheng, Jingwei; Xu, Zhipeng; Hou, Xin; Xu, Yingchun

2015-04-01

The objective of this study was to better understand the in vitro activity of flomoxef against clinical pathogens. A total of 545 clinical isolates, including Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus, Streptococcus pneumoniae, and Streptococcus pyogenes, were isolated consecutively from clinical specimens from Peking Union Medical College Hospital in 2013. MICs were determined using broth microdilution method. esbl and ampC genes were detected by polymerase chain reaction and sequencing. Flomoxef showed excellent activity against E. coli, K. pneumoniae, and P. mirabilis isolates, with susceptibility rate of 88.8%, 88.3%, and 97.7%, separately. Moreover, flomoxef exhibited great activity against extended-spectrum beta-lactamase (ESBL) producers, with MIC50/MIC90 of 0.125/(0.5-1) μg/mL. Flomoxef showed MIC50/MIC90 of 0.5/0.5 μg/mL against MSSA, 0.125/0.25 μg/mL against S. pyogenes, and 2/16 μg/mL against S. pneumoniae. In conclusion, flomoxef is one of the cephamycins showing excellent activity against ESBL-producing or ESBL-nonproducing E. coli, K. pneumoniae, and P. mirabilis and was also potent against MSSA, S. pyogenes, and S. pneumoniae. Copyright © 2015 Elsevier Inc. All rights reserved.

Sensitivity and specificity of the Streptococcus pneumoniae urinary antigen test for unconcentrated urine from adult patients with pneumonia: a meta-analysis.

PubMed

Horita, Nobuyuki; Miyazawa, Naoki; Kojima, Ryota; Kimura, Naoko; Inoue, Miyo; Ishigatsubo, Yoshiaki; Kaneko, Takeshi

2013-11-01

Studies on the sensitivity and specificity of the Binax Now Streptococcus pneumonia urinary antigen test (index test) show considerable variance of results. Those written in English provided sufficient original data to evaluate the sensitivity and specificity of the index test using unconcentrated urine to identify S. pneumoniae infection in adults with pneumonia. Reference tests were conducted with at least one culture and/or smear. We estimated sensitivity and two specificities. One was the specificity evaluated using only patients with pneumonia of identified other aetiologies ('specificity (other)'). The other was the specificity evaluated based on both patients with pneumonia of unknown aetiology and those with pneumonia of other aetiologies ('specificity (unknown and other)') using a fixed model for meta-analysis. We found 10 articles involving 2315 patients. The analysis of 10 studies involving 399 patients yielded a pooled sensitivity of 0.75 (95% confidence interval: 0.71-0.79) without heterogeneity or publication bias. The analysis of six studies involving 258 patients yielded a pooled specificity (other) of 0.95 (95% confidence interval: 0.92-0.98) without no heterogeneity or publication bias. We attempted to conduct a meta-analysis with the 10 studies involving 1916 patients to estimate specificity (unknown and other), but it remained unclear due to moderate heterogeneity and possible publication bias. In our meta-analysis, sensitivity of the index test was moderate and specificity (other) was high; however, the specificity (unknown and other) remained unclear. © 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.

Predominance of ST320 among Streptococcus pneumoniae serotype 19A isolates from 10 Asian countries.

PubMed

Shin, Juyoun; Baek, Jin Yang; Kim, So Hyun; Song, Jae-Hoon; Ko, Kwan Soo

2011-05-01

After 7-valent pneumococcal conjugate vaccine (PCV7) introduction, non-vaccine serotypes such as 19A are increasing among Streptococcus pneumoniae. However, only limited data on 19A S. pneumoniae are available in Asian countries. Out of 1637 S. pneumoniae clinical pneumonia isolates collected during 2008 and 2009 from 10 Asian countries (Korea, Malaysia, Taiwan, Thailand, Saudi Arabia, Hong Kong, India, Japan, the Philippines and Vietnam), 91 serotype 19A S. pneumoniae isolates were identified. Capsular swelling reaction identified serotype 19A isolates. Antimicrobial susceptibility testing was performed on the serotype 19A isolates using the broth microdilution method, and the genotypes of the isolates were assessed using multilocus sequence typing. Thirty different sequence types (STs) were identified. The most prevalent clone was ST320 (46 isolates, 51.1%). ST320 was found in Hong Kong, India, Korea, Malaysia, Saudi Arabia and Taiwan. ST320 isolates were mostly multidrug resistant (MDR) and showed significantly higher resistance rates than other STs for cefuroxime, clindamycin, and trimethoprim/sulfamethoxazole. Although diverse clones were identified among 19A S. pneumoniae isolates, MDR ST320 was the predominant clone in Asian countries. Its predominance, even in countries with no or low coverage of PCV7, may indicate that its emergence and dissemination was due to more than just vaccine selection pressure in Asian countries. A longitudinal investigation of the change of serotypes and genotypes since the introduction of PCV7 is required to understand the emergence and dissemination mechanisms of a certain clone of 19A S. pneumoniae isolates.

[Orbital cellulitis complicated by subperiosteal abscess due to Streptococcus pyogenes infection].

PubMed

Ruíz Carrillo, José Daniel; Vázquez Guerrero, Edwin; Mercado Uribe, Mónica Cecilia

Orbital cellulitis is an infectious disease that is very common in pediatric patients, in which severe complications may develop. Etiological agents related to this disease are Haemophilus influenzae B, Staphylococcus aureus, Streptococcus pneumoniae and Moraxella catarrhalis, which correspond to 95% of cases. Moreover, Streptococcus beta hemolytic and anaerobic microorganisms may also be present corresponding to < 5% of the cases. We present an uncommon case of cellulitis complicated by sub-periosteal abscess caused by Streptococcus pyogenes (Group A beta hemolytic streptococcus). A 9-year-old male patient with a history of deficit disorder and hyperactivity since 5 years of age. His current condition started with erythema in the external edge of the right eye, increase in peri-orbicular volume with limitation of eyelid opening, progression to proptosis, pain with eye movements and conjunctival purulent discharge. Image studies reported subperiosteal abscess and preseptal right with extraocular cellulitis. The patient started with empirical antibiotic treatment, surgical drainage and culture of purulent material from which Streptococcus pyogenes was isolated. Due to the implementation of vaccination schemes against H. influenza and S. pneumoniae since the 90s, the cases by these pathogens have decreased, causing new bacteria to take place as the cause of the infection. The importance of considering S. pyogenes as an etiology of orbital cellulitis is the rapid progression to abscess formation, and the few cases described in the literature. Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

[Prevalence of nasal carriage of Staphylococcus aureus and Streptococcus pneumoniae in Primary Care and factors associated with colonization].

PubMed

Boada, Albert; Almeda, Jesús; Grenzner, Elisabet; Pons-Vigués, Mariona; Morros, Rosa; Juvé, Rosa; Simonet, Pere J; den Heijer, Casper D J; Bolíbar, Bonaventura

2015-01-01

To determine (i) the prevalence of Staphylococcus aureus (S.aureus) and Streptococcus pneumoniae (S.pneumoniae) nasal carriage in Primary Health Care patients in area of Barcelona, and (ii) the factors associated with S.aureus and S.pneumoniae colonization. Multi-center cross-sectional study conducted in 2010-2011 with the participation of 27 Primary Health Care professionals. Nasopharyngeal swabs were obtained from 3,969 patients over 4 years of age who did not present with any sign of infection. S.aureus and/or S.pneumoniae carrier state. socio-demographic characteristics, health status, vaccination status, occupation, and living with children. A descriptive analysis was performed. The prevalence of carriers of S.aureus and/or S.pneumoniae was calculated and logistic regression models were adjusted by age. In children from 4 to 14 years old, the prevalence of S.aureus carriers was 35.7%, of S.pneumoniae 27.1%, and 5.8% were co-colonized. In adults older than 14 years old, the prevalence was 17.8%, 3.5%, and 0.5%, respectively. In children, S.aureus carrier state was inversely associated with S.pneumoniae carrier state; S.pneumoniae was associated with younger age, and inversely associated with S.aureus carrier state. In adults, being a carrier of S.aureus was associated with male gender, younger age, and a health-related occupation, whereas S.pneumoniae carrier state was associated with living with children under 6 years of age. The proportion of co-colonized carriers was low (1.0%). The proportion of S.aureus and S.pneumoniae carriers was higher in children than in adults. Age was the only factor associated with healthy carrier status for S.aureus and for S.pneumoniae. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Tn5253 family integrative and conjugative elements carrying mef(I) and catQ determinants in Streptococcus pneumoniae and Streptococcus pyogenes.

PubMed

Mingoia, Marina; Morici, Eleonora; Morroni, Gianluca; Giovanetti, Eleonora; Del Grosso, Maria; Pantosti, Annalisa; Varaldo, Pietro E

2014-10-01

The linkage between the macrolide efflux gene mef(I) and the chloramphenicol inactivation gene catQ was first described in Streptococcus pneumoniae (strain Spn529), where the two genes are located in a module designated IQ element. Subsequently, two different defective IQ elements were detected in Streptococcus pyogenes (strains Spy029 and Spy005). The genetic elements carrying the three IQ elements were characterized, and all were found to be Tn5253 family integrative and conjugative elements (ICEs). The ICE from S. pneumoniae (ICESpn529IQ) was sequenced, whereas the ICEs from S. pyogenes (ICESpy029IQ and ICESpy005IQ, the first Tn5253-like ICEs reported in this species) were characterized by PCR mapping, partial sequencing, and restriction analysis. ICESpn529IQ and ICESpy029IQ were found to share the intSp 23FST81 integrase gene and an identical Tn916 fragment, whereas ICESpy005IQ has int5252 and lacks Tn916. All three ICEs were found to lack the linearized pC194 plasmid that is usually associated with Tn5253-like ICEs, and all displayed a single copy of a toxin-antitoxin operon that is typically contained in the direct repeats flanking the excisable pC194 region when this region is present. Two different insertion sites of the IQ elements were detected, one in ICESpn529IQ and ICESpy029IQ, and another in ICESpy005IQ. The chromosomal integration of the three ICEs was site specific, depending on the integrase (intSp 23FST81 or int5252). Only ICESpy005IQ was excised in circular form and transferred by conjugation. By transformation, mef(I) and catQ were cotransferred at a high frequency from S. pyogenes Spy005 and at very low frequencies from S. pneumoniae Spn529 and S. pyogenes Spy029. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

The Protein Interactome of Streptococcus pneumoniae and Bacterial Meta-interactomes Improve Function Predictions

PubMed Central

Rajagopala, S. V.; Blazie, S. M.; Parrish, J. R.; Khuri, S.; Finley, R. L.

2017-01-01

ABSTRACT The functions of roughly a third of all proteins in Streptococcus pneumoniae, a significant human-pathogenic bacterium, are unknown. Using a yeast two-hybrid approach, we have determined more than 2,000 novel protein interactions in this organism. We augmented this network with meta-interactome data that we defined as the pool of all interactions between evolutionarily conserved proteins in other bacteria. We found that such interactions significantly improved our ability to predict a protein’s function, allowing us to provide functional predictions for 299 S. pneumoniae proteins with previously unknown functions. IMPORTANCE Identification of protein interactions in bacterial species can help define the individual roles that proteins play in cellular pathways and pathogenesis. Very few protein interactions have been identified for the important human pathogen S. pneumoniae. We used an experimental approach to identify over 2,000 new protein interactions for S. pneumoniae, the most extensive interactome data for this bacterium to date. To predict protein function, we used our interactome data augmented with interactions from other closely related bacteria. The combination of the experimental data and meta-interactome data significantly improved the prediction results, allowing us to assign possible functions to a large number of poorly characterized proteins. PMID:28744484

Fluorescence Imaging of Streptococcus pneumoniae with the Helix pomatia agglutinin (HPA) As a Potential, Rapid Diagnostic Tool

PubMed Central

Domenech, Mirian; García, Ernesto

2017-01-01

Streptococcus pneumoniae is a common human pathogen and a major causal agent of life-threatening infections that can either be respiratory or non-respiratory. It is well known that the Helix pomatia (edible snail) agglutinin (HPA) lectin shows specificity for terminal αGalNAc residues present, among other locations, in the Forssman pentasaccharide (αGalNAc1→3βGalNAc1→3αGal1→4βGal1→4βGlc). Based on experiments involving choline-independent mutants and different growth conditions, we propose here that HPA recognizes the αGalNAc terminal residues of the cell wall teichoic and lipoteichoic acids of S. pneumoniae. In addition, experimental evidence showing that pneumococci can be specifically labeled with HPA when growing as planktonic cultures as well as in mixed biofilms of S. pneumoniae and Haemophilus influenzae has been obtained. It should be underlined that pneumococci were HPA-labeled despite of the presence of a capsule. Although some non-pneumococcal species also bind the agglutinin, HPA-binding combined with fluorescence microscopy constitutes a suitable tool for identifying S. pneumoniae and, if used in conjunction with Gram staining and/or other suitable technique like antigen detection, it may potentially facilitate a fast and accurate diagnosis of pneumococcal infections. PMID:28769901

Export requirements of pneumolysin in Streptococcus pneumoniae.

PubMed

Price, Katherine E; Greene, Neil G; Camilli, Andrew

2012-07-01

Streptococcus pneumoniae is a major causative agent of otitis media, pneumonia, bacteremia, and meningitis. Pneumolysin (Ply), a member of the cholesterol-dependent cytolysins (CDCs), is produced by virtually all clinical isolates of S. pneumoniae, and ply mutant strains are severely attenuated in mouse models of colonization and infection. In contrast to all other known members of the CDC family, Ply lacks a signal peptide for export outside the cell. Instead, Ply has been hypothesized to be released upon autolysis or, alternatively, via a nonautolytic mechanism that remains undefined. We show that an exogenously added signal sequence is not sufficient for Sec-dependent Ply secretion in S. pneumoniae but is sufficient in the surrogate host Bacillus subtilis. Previously, we showed that Ply is localized primarily to the cell wall compartment in the absence of detectable cell lysis. Here we show that Ply released by autolysis cannot reassociate with intact cells, suggesting that there is a Ply export mechanism that is coupled to cell wall localization of the protein. This putative export mechanism is capable of secreting a related CDC without its signal sequence. We show that B. subtilis can export Ply, suggesting that the export pathway is conserved. Finally, through truncation and domain swapping analyses, we show that export is dependent on domain 2 of Ply.

Export Requirements of Pneumolysin in Streptococcus pneumoniae

PubMed Central

Price, Katherine E.; Greene, Neil G.

2012-01-01

Streptococcus pneumoniae is a major causative agent of otitis media, pneumonia, bacteremia, and meningitis. Pneumolysin (Ply), a member of the cholesterol-dependent cytolysins (CDCs), is produced by virtually all clinical isolates of S. pneumoniae, and ply mutant strains are severely attenuated in mouse models of colonization and infection. In contrast to all other known members of the CDC family, Ply lacks a signal peptide for export outside the cell. Instead, Ply has been hypothesized to be released upon autolysis or, alternatively, via a nonautolytic mechanism that remains undefined. We show that an exogenously added signal sequence is not sufficient for Sec-dependent Ply secretion in S. pneumoniae but is sufficient in the surrogate host Bacillus subtilis. Previously, we showed that Ply is localized primarily to the cell wall compartment in the absence of detectable cell lysis. Here we show that Ply released by autolysis cannot reassociate with intact cells, suggesting that there is a Ply export mechanism that is coupled to cell wall localization of the protein. This putative export mechanism is capable of secreting a related CDC without its signal sequence. We show that B. subtilis can export Ply, suggesting that the export pathway is conserved. Finally, through truncation and domain swapping analyses, we show that export is dependent on domain 2 of Ply. PMID:22563048

The Streptococcus sanguinis Competence Regulon Is Not Required for Infective Endocarditis Virulence in a Rabbit Model

PubMed Central

Callahan, Jill E.; Munro, Cindy L.; Kitten, Todd

2011-01-01

Streptococcus sanguinis is an important component of dental plaque and a leading cause of infective endocarditis. Genetic competence in S. sanguinis requires a quorum sensing system encoded by the early comCDE genes, as well as late genes controlled by the alternative sigma factor, ComX. Previous studies of Streptococcus pneumoniae and Streptococcus mutans have identified functions for the >100-gene com regulon in addition to DNA uptake, including virulence. We investigated this possibility in S. sanguinis. Strains deleted for the comCDE or comX master regulatory genes were created. Using a rabbit endocarditis model in conjunction with a variety of virulence assays, we determined that both mutants possessed infectivity equivalent to that of a virulent control strain, and that measures of disease were similar in rabbits infected with each strain. These results suggest that the com regulon is not required for S. sanguinis infective endocarditis virulence in this model. We propose that the different roles of the S. sanguinis, S. pneumoniae, and S. mutans com regulons in virulence can be understood in relation to the pathogenic mechanisms employed by each species. PMID:22039480

Effects of the 10-Valent Pneumococcal Nontypeable Haemophilus influenzae Protein D–Conjugate Vaccine on Nasopharyngeal Bacterial Colonization in Young Children: A Randomized Controlled Trial

PubMed Central

van den Bergh, Menno R.; Spijkerman, Judith; Swinnen, Kristien M.; François, Nancy A.; Pascal, Thierry G.; Borys, Dorota; Schuerman, Lode; IJzerman, Ed P. F.; Bruin, Jacob P.; van der Ende, Arie; Veenhoven, Reinier H.; Sanders, Elisabeth A. M.

2013-01-01

Background. This study evaluated the effects of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D–conjugate vaccine (PHiD-CV) on nasopharyngeal bacterial colonization compared with the 7-valent pneumococcal conjugate vaccine (7vCRM) in young children. Methods. A randomized controlled trial in the Netherlands, initiated 2 years after 7vCRM introduction, was conducted between 1 April 2008 and 1 December 2010. Infants (N = 780) received either PHiD-CV or 7vCRM (2:1) at 2, 3, 4, and 11–13 months of age. Nasopharyngeal samples taken at 5, 11, 14, 18, and 24 months of age were cultured to detect Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus. Polymerase chain reaction assays quantified H. influenzae and S. pneumoniae and confirmed H. influenzae as nontypeable (NTHi). Primary outcome measure was vaccine efficacy (VE) against NTHi colonization. Results. In both groups, NTHi colonization increased with age from 33% in 5-month-olds to 65% in 24-month-olds. Three months postbooster, VE against colonization was 0.5% (95% confidence interval [CI], −21.8% to 18.4%) and VE against acquisition 10.9% (95% CI, −31.3% to 38.9%). At each sampling moment, no differences between groups in either NTHi prevalence or H. influenzae density were detected. Streptococcus pneumoniae (range, 39%–57%), M. catarrhalis (range, 63%­–69%), and S. aureus (range, 9%–30%) colonization patterns were similar between groups. Conclusions. PHiD-CV had no differential effect on nasopharyngeal NTHi colonization or H. influenzae density in healthy Dutch children up to 2 years of age, implying that herd effects for NTHi are not to be expected. Other bacterial colonization patterns were also similar. Clinical Trials Registration NCT00652951. PMID:23118268

[Experience with bronchomunal used in the combined treatment of patients with bronchial asthma and chronic obstructive pulmonary disease].

PubMed

Antonova, L P; Romanov, V V; Averbakh, M M

2008-01-01

The paper presents the results of treatment in 30 patients aged 16-59 years who have bronchial asthma and chronic obstructive pulmonary disease, by using a bacterial vaccine (bronchomunal) containing antigens of opportunistic bacteria: Streptococcus pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus viridans, Streptococcus piogenes, Moraxella catarrhalis. Immunotherapy with the vaccine had good and excellent effects in 73.33 of cases; the mean duration of acute respiratory viral infection decreased from 16 to 9 days after vaccination and a need for antibiotics. In the comparison group, a good effect was noted in 40% of the patients during one-year follow-up; the difference was statistically significant. The vaccine's tolerance was good; only 3 (9.9%) patients were observed to have vaccination-induced complications: exacerbations of chronic maxillary sinusitis and chronic bronchitis in 2 and 1 patients, respectively. The positive effect of bronchomunal was associated with the better values of cellular immunity, stabilized phagocytosis, and lower IgE levels.

Novel role for the Streptococcus pneumoniae toxin pneumolysin in the assembly of biofilms.

PubMed

Shak, Joshua R; Ludewick, Herbert P; Howery, Kristen E; Sakai, Fuminori; Yi, Hong; Harvey, Richard M; Paton, James C; Klugman, Keith P; Vidal, Jorge E

2013-09-10

Streptococcus pneumoniae is an important commensal and pathogen responsible for almost a million deaths annually in children under five. The formation of biofilms by S. pneumoniae is important in nasopharyngeal colonization, pneumonia, and otitis media. Pneumolysin (Ply) is a toxin that contributes significantly to the virulence of S. pneumoniae and is an important candidate as a serotype-independent vaccine target. Having previously demonstrated that a luxS knockout mutant was unable to form early biofilms and expressed less ply mRNA than the wild type, we conducted a study to investigate the role of Ply in biofilm formation. We found that Ply was expressed in early phases of biofilm development and localized to cellular aggregates as early as 4 h postinoculation. S. pneumoniae ply knockout mutants in D39 and TIGR4 backgrounds produced significantly less biofilm biomass than wild-type strains at early time points, both on polystyrene and on human respiratory epithelial cells, cultured under static or continuous-flow conditions. Ply's role in biofilm formation appears to be independent of its hemolytic activity, as S. pneumoniae serotype 1 strains, which produce a nonhemolytic variant of Ply, were still able to form biofilms. Transmission electron microscopy of biofilms grown on A549 lung cells using immunogold demonstrated that Ply was located both on the surfaces of pneumococcal cells and in the extracellular biofilm matrix. Altogether, our studies demonstrate a novel role for pneumolysin in the assembly of S. pneumoniae biofilms that is likely important during both carriage and disease and therefore significant for pneumolysin-targeting vaccines under development. The bacterium Streptococcus pneumoniae (commonly known as the pneumococcus) is commonly carried in the human nasopharynx and can spread to other body sites to cause disease. In the nasopharynx, middle ear, and lungs, the pneumococcus forms multicellular surface-associated structures called biofilms. Pneumolysin is an important toxin produced by almost all S. pneumoniae strains, extensively studied for its ability to cause damage to human tissue. In this paper, we demonstrate that pneumolysin has a previously unrecognized role in biofilm formation by showing that strains without pneumolysin are unable to form the same amount of biofilm on plastic and human cell substrates. Furthermore, we show that the role of pneumolysin in biofilm formation is separate from the hemolytic activity responsible for tissue damage during pneumococcal diseases. This novel role for pneumolysin suggests that pneumococcal vaccines directed against this protein should be investigated for their potential impact on biofilms formed during carriage and disease.

[Antibiotic resistance analysis of Streptococcus pneumoniae isolates from the hospitalized children in Shanxi Children's Hospital from 2012 to 2014].

PubMed

Ge, L L; Han, Z Y; Liu, A H; Zhu, L; Meng, J H

2017-02-02

Objective: To investigate the antibiotic resistance status of Streptococcus pneumoniae isolates from hospitalized children in Shanxi Children's Hospital. Method: E-test and Kirby-Bauer methods were applied to determine drug sensitivity of the isolates collected from the body fluid specimens of hospitalized children in Shanxi Children's Hospital from January 2012 to December 2014. The antimicrobial sensitivity and minimum inhibitory concentration (MIC) of Streptococcus pneumoniae to the conventional antibiotics were analyzed, in order to compare the annual trends of non-invasive isolates, while the differentiation of sensitivity from specimens. The comparison of rates was performed by Chi-squared test and Fisher's exact test. Result: A total of 671 isolates of streptococcus pneumoniae were obtained, which could be divided as non-invasive isolates(607), invasive isolates from non-cerebrospinal fluid(non-CSF)(40) and invasive isolates from cerebrospinal fluid(CSF)(24). The antimicrobial sensitivity(isolates(%)) of the 671 isolates were respectively vancomycin 671(100.0%), linezolid 671(100.0%), levofloxacin 665(99.1%), penicillin 595(88.7%), ceftriaxone 516(76.9%), cefotaxime 512(76.3%), sulfamethoxazole-trimethoprin(SMZ-TMP) 103(15.4%), clindamycin 28(4.2%), tetracycline 26(3.9%), erythromycin 12(1.8%). From 2012 to 2014, the susceptibility rates of non-invasive isolates to penicillin every year were 95.0%(96/101), 97.3%(110/113), 87.3%(343/393), respectively, and there was significant difference among the three years(χ(2)=13.266, P <0.05), and the values of MIC(50, )MIC(90) and the maximum values of MIC(mg/L) of penicillin were 0.064, 2.000, 6.000 in 2012, which grew up to 1.000, 3.000, 16.000 in 2014. There was no significant difference in the susceptibility rate of non-invasive isolates to ceftriaxone and cefotaxime during these three years, (χ(2)=1.172, 1.198, both P >0.05). On the other hand, the values of MIC(50, )MIC(90) and the maximum value of MIC(mg/L) of ceftriaxone and cefotaxime both increased from 0.500, 2.000, 8.000 in 2012 to 0.750, 4.000, 32.000 in 2014. There was no significant difference in the susceptibility rate of non-invasive isolates to the rest antibiotic. Based on the same examining standard of CSF, the antimicrobial sensitivity(isolates(%)) of the non-invasive isolates to ceftriaxone, cefotaxime, SMZ-TMP were respectively 281(46.3%), 278(45.8%), 78(12.9%), were significantly lower than the susceptibility rate of the invasive isolates from non-CSF (28(70%), 28(70%), 14(35%), χ(2)=8.453, 8.817, 15.094, all P <0.012 5), and lower than the invasive isolates from CSF (18(75%), 18(75%), χ(2)=7.631, 7.905, P <0.012 5; 11(45.8%), P =0.001). The sensitivity of the isolates to the rest antibiotics were similar( P >0.05). Conclusion: More than 95.0% strains of the streptococcus pneumoniae isolates from the hospitalized children in Shanxi Children's Hospital were sensitive to vancomycin, linezolid, levofloxacin, and the susceptibility rate of penicillin, ceftriaxone, cefotaxime were 88.7%, 76.9%, 76.3%. However, less than 20.0% of streptococcus pneumoniae were sensitive to erythromycin, clindamycin, SMZ-TMP and tetracycline. The susceptibility rate of penicillin of non-invasive Streptococcus pneumoniae declined by these years, and the differences to ceftriaxone and cefotaxime can be neglected, but the values of MIC(50, )MIC(90) and the maximum value of MIC of all were linearly rising. The susceptibility rate of antibiotics to ceftriaxone and cefotaxime of the non-invasive isolates was lower than the invasive isolates.

[Levofloxacin in children].

PubMed

Grimprel, E; Cohen, R

2010-09-01

Levofloxacin (levogyre form of ofloxacin) has been approved for the treatment of acute and chronic sinusitis, pneumonia, and exacerbation of bronchopulmonary diseases, urinary, digestive and biliary infections in adults. Its pharmacokinetic properties and microbiological spectrum, including penicillin non-susceptible Streptococcus pneumoniae, methicillin-resistant Staphylococcus aureus, and Mycoplasma pneumoniae, suggest a potential interest in drug-resistant acute otitis media and community-acquired pneumonia. Only few studies have been performed in the paediatric population but they provided encouraging efficacy and safety data. Complementary data are needed before considering its use in Europe in the setting of a paediatric investigation plan. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

[Antibiotic management of presumptive bacterial meningitis in adults (rational, methods, course, and follow-up)].

PubMed

Ansart, S

2009-01-01

The annual incidence of community acquired meningitis ranges between 0.6 and four per 100,000 adults in industrialized countries. The most common causative bacteria are Streptococcus pneumoniae, Neisseria meningitidis, Listeria monocytogenes. The emergence of resistance to antibiotics, especially for S. pneumoniae, could explain the clinical failure of third generation cephalosporins used to treat adults with S. pneumoniae meningitis. The present therapeutic suggestions are more based on the extrapolation of an experimental model than on relevant clinical trials.

Bacterial Pathogens Associated with Community-acquired Pneumonia in Children Aged Below Five Years.

PubMed

Das, Anusmita; Patgiri, Saurav J; Saikia, Lahari; Dowerah, Pritikar; Nath, Reema

2016-03-01

To determine the spectrum of bacterial pathogens causing community-acquired pneumonia in children below 5 years of age. Children aged below 5 years satisfying the WHO criteria for pneumonia, severe pneumonia or very severe pneumonia, and with the presence of lung infiltrates on chest X-ray were enrolled. Two respiratory samples, one for culture and the other for PCR analysis, and a blood sample for culture were collected from every child. Of the 180 samples processed, bacterial pathogens were detected in 64.4%. Streptococcus pneumoniae and Hemophilus influenzae were most frequently detected. The performance of PCR analysis and culture were identical for the typical bacterial pathogens; atypical pathogens were detected by PCR analysis only. S. pneumoniae and H. influenza were the most commonly detected organisms from respiratory secretions of children with community acquired pneumonia.

Community-acquired pneumonia in children - a changing spectrum of disease.

PubMed

le Roux, David M; Zar, Heather J

2017-10-01

Pneumonia remains the leading cause of death in children outside the neonatal period, despite advances in prevention and management. Over the last 20 years, there has been a substantial decrease in the incidence of childhood pneumonia and pneumonia-associated mortality. New conjugate vaccines against Haemophilus influenzae type b and Streptococcus pneumoniae have contributed to decreases in radiologic, clinical and complicated pneumonia cases and have reduced hospitalization and mortality. The importance of co-infections with multiple pathogens and the predominance of viral-associated disease are emerging. Better access to effective preventative and management strategies is needed in low- and middle-income countries, while new strategies are needed to address the residual burden of disease once these have been implemented.

Competence for Genetic Transformation in Streptococcus pneumoniae: Mutations in σA Bypass the comW Requirement

PubMed Central

Tovpeko, Yanina

2014-01-01

Competence for genetic transformation in the genus Streptococcus depends on an alternative sigma factor, σX, for coordinated synthesis of 23 proteins, which together establish the X state by permitting lysis of incompetent streptococci, uptake of DNA fragments, and integration of strands of that DNA into the resident genome. Initiation of transient accumulation of high levels of σX is coordinated between cells by transcription factors linked to peptide pheromone signals. In Streptococcus pneumoniae, elevated σX is insufficient for development of full competence without coexpression of a second competence-specific protein, ComW. ComW, shared by eight species in the Streptococcus mitis and Streptococcus anginosus groups, is regulated by the same pheromone circuit that controls σX, but its role in expression of the σX regulon is unknown. Using the strong, but not absolute, dependence of transformation on comW as a selective tool, we collected 27 independent comW bypass mutations and mapped them to 10 single-base transitions, all within rpoD, encoding the primary sigma factor subunit of RNA polymerase, σA. Eight mapped to sites in rpoD region 4 that are implicated in interaction with the core β subunit, indicating that ComW may act to facilitate competition of the alternative sigma factor σX for access to core polymerase. PMID:25112479

A cohort study of the impact and acquisition of naspharyngeal carriage of Streptococcus pneumoniae during the Hajj.

PubMed

Memish, Ziad A; Al-Tawfiq, Jaffar A; Almasri, Malak; Akkad, Nadia; Yezli, Saber; Turkestani, Abdulhafeez; van der Linden, Mark; Assiri, Abdullah

2016-01-01

The annual Muslim pilgrimage attracts over two million pilgrims who gather in a limited time and space. The pilgrimage carries the potential risk of increase risk of the acquisition of Streptococcus pneumonia. In this cohort study, we evaluate the effect of the Hajj on the prevalence of pneumococcal serotype nasopharyngeal carriage in the Hajj pilgrim population. The secondary objective is to evaluate the effects of the mass gathering on carriage of invasive pneumococcal serotypes. This is a prospective cohort study with two data collection periods: at the beginning and at the end of the Hajj. Nasopharyngeal samples were taken via a standardized swabbing method. A total of 1175 pilgrims were enrolled at the beginning of the study and 1155 (98.3%) were included at the second part of the study. The pre-Hajj samples were obtained at a mean of 0 days and the post-Hajj sampling occurred at a mean of 15 days after arrival to Saudi Arabia. The overall carriage rate of Streptococcus pneumoniae in the pre- and post-Hajj was 1.8% and 7.1% (P = 0.0016). The potential coverage of the 7-valent pneumococcal conjugate vaccine (PCV7), PCV10 and PCV13 were 15.5%, 19.1%; and 35.5%, respectively. The coverage for the 23-valent pneumococcal polysaccharide vaccine (PPV23) was 40%. Although there was an increase in the acquisition of S. pneumoniae, its magnitude is low which does not support public health recommendations for general pneumococcal vaccination of pilgrims except those at risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nebulized C1-Esterase Inhibitor does not Reduce Pulmonary Complement Activation in Rats with Severe Streptococcus Pneumoniae Pneumonia.

PubMed

de Beer, Friso; Lagrand, Wim; Glas, Gerie J; Beurskens, Charlotte J P; van Mierlo, Gerard; Wouters, Diana; Zeerleder, Sacha; Roelofs, Joris J T H; Juffermans, Nicole P; Horn, Janneke; Schultz, Marcus J

2016-12-01

Complement activation plays an important role in the pathogenesis of pneumonia. We hypothesized that inhibition of the complement system in the lungs by repeated treatment with nebulized plasma-derived human C1-esterase inhibitor reduces pulmonary complement activation and subsequently attenuates lung injury and lung inflammation. This was investigated in a rat model of severe Streptococcus pneumoniae pneumonia. Rats were intra-tracheally challenged with S. pneumoniae to induce pneumonia. Nebulized C1-esterase inhibitor or saline (control animals) was repeatedly administered to rats, 30 min before induction of pneumonia and every 6 h thereafter. Rats were sacrificed 20 or 40 h after inoculation with bacteria. Brochoalveolar lavage fluid and lung tissue were obtained for measuring levels of complement activation (C4b/c), lung injury and inflammation. Induction of pneumonia was associated with pulmonary complement activation (C4b/c at 20 h 1.24 % [0.56-2.59] and at 40 h 2.08 % [0.98-5.12], compared to 0.50 % [0.07-0.59] and 0.03 % [0.03-0.03] in the healthy control animals). The functional fraction of C1-INH was detectable in BALF, but no effect was found on pulmonary complement activation (C4b/c at 20 h 0.73 % [0.16-1.93] and at 40 h 2.38 % [0.54-4.19]). Twenty hours after inoculation, nebulized C1-esterase inhibitor treatment reduced total histology score, but this effect was no longer seen at 40 h. Nebulized C1-esterase inhibitor did not affect other markers of lung injury or lung inflammation. In this negative experimental animal study, severe S. pneumoniae pneumonia in rats is associated with pulmonary complement activation. Repeated treatment with nebulized C1-esterase inhibitor, although successfully delivered to the lungs, does not affect pulmonary complement activation, lung inflammation or lung injury.

Antimicrobial susceptibilities and capsular types of invasive Streptococcus pneumoniae isolated in children in Mexico City.

PubMed

Echániz-Aviles, G; Velázquez-Meza, M E; Carnalla-Barajas, M N; Soto-Noguerón, A; Solórzano-Santos, F; Pérez Miravete, A; Gatica-Marquina, R; di Fabio, J L

1997-01-01

As part of the Sistema Regional de Vacunas (SIREVA) initiative, we conducted a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children less than 5 years old. We collected 220 isolates and found 33 of the 90 known types, with type 23F as the most common followed by types 6A+B, 14, 19F, and 19A. High penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Twenty-nine (13.1%) were resistant to erythromycin, 95 (43.1%) were resistant to chloramphenicol, and 24 (10.9%) were resistant to cefotaxime. No strains were resistant to vancomycin.

Overexpression, purification and crystallization of a choline-binding protein CbpI from Streptococcus pneumoniae

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

Paterson, Neil G., E-mail: neison@chem.gla.ac.uk; Riboldi-Tunicliffe, Alan; Mitchell, Timothy J.

2006-07-01

The choline-binding protein CbpI from S. pneumoniae has been purified and crystallized and diffraction data have been collected to 3.5 Å resolution. The choline-binding protein CbpI from Streptococcus pneumoniae is a 23.4 kDa protein with no known function. The protein has been successfully purified initially using Ni–NTA chromatography and to homogeneity using Q-Sepharose ion-exchange resin as an affinity column. CbpI was crystallized using PEG 3350 as a precipitant and X-ray crystallographic analysis showed that the crystals belonged to the tetragonal space group P4, with unit-cell parameters a = b = 83.31, c = 80.29 Å, α = β = γmore » = 90°. The crystal contains two molecules in the asymmetric unit with a solvent content of 55.7% (V{sub M} = 2.77 Å{sup 3} Da{sup −1}) and shows a diffraction limit of 3.5 Å.« less

Concurrent Infection with Hepatitis C Virus and Streptococcus pneumoniae.

PubMed

Marrie, Thomas J; Tyrrell, Gregory J; Majumdar, Sumit R; Eurich, Dean T

2017-07-01

Little is known about concurrent infection with hepatitis C virus (HCV) and Streptococcus pneumoniae, which causes invasive pneumococcal disease (IPD). We hypothesized that co-infection with HCV and S. pneumoniae would increase risk for death and complications. We captured sociodemographic and serologic data for adults with IPD in a population-based cohort study in northern Alberta, Canada, during 2000-2014. IPD patients infected with HCV were compared with IPD patients not infected with HCV for risk of in-hospital deaths and complications by using multivariable logistic regression. A total of 355 of 3,251 patients with IPD were co-infected with HCV. The in-hospital mortality rate was higher for IPD patients infected with HCV. Prevalence of most IPD-related complications (e.g., cellulitis, acute kidney injury, mechanical ventilation) was also higher in HCV-infected patients. Infection with HCV is common in patients with IPD, and HCV is independently associated with an increased risk for serious illness and death.

An outbreak of fatal hemorrhagic pneumonia caused by Streptococcus equi subsp. zooepidemicus in shelter dogs.

PubMed

Byun, Jae Won; Yoon, Soon Seek; Woo, Gye-Hyeong; Jung, Byeong Yeal; Joo, Yi-Seok

2009-09-01

An outbreak of fatal hemorrhagic pneumonia with 70-90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea.

An outbreak of fatal hemorrhagic pneumonia caused by Streptococcus equi subsp. zooepidemicus in shelter dogs

PubMed Central

Yoon, Soon-Seek; Woo, Gye-Hyeong; Jung, Byeong Yeal; Joo, Yi-Seok

2009-01-01

An outbreak of fatal hemorrhagic pneumonia with 70~90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea. PMID:19687630

The RFK catalytic cycle of the pathogen Streptococcus pneumoniae shows species-specific features in prokaryotic FMN synthesis.

PubMed

Sebastián, María; Velázquez-Campoy, Adrián; Medina, Milagros

2018-12-01

Emergence of multidrug-resistant bacteria forces us to explore new therapeutic strategies, and proteins involved in key metabolic pathways are promising anti-bacterial targets. Bifunctional flavin-adenine dinucleotide (FAD) synthetases (FADS) are prokaryotic enzymes that synthesise the flavin mononucleotide (FMN) and FAD cofactors. The FADS from the human pathogen Streptococcus pneumoniae (SpnFADS)-causative agent of pneumonia in humans - shows relevant catalytic dissimilarities compared to other FADSs. Here, by integrating thermodynamic and kinetic data, we present a global description of the riboflavin kinase activity of SpnFADS, as well as of the inhibition mechanisms regulating this activity. Our data shed light on biophysical determinants that modulate species-specific conformational changes leading to catalytically competent conformations, as well as binding rates and affinities of substrates versus products. This knowledge paves the way for the development of tools - that taking advantage of the regulatory dissimilarities during FMN biosynthesis in different species - might be used in the discovery of specific anti-pneumococcal drugs.

Purpura fulminans associated with Streptococcus pneumoniae septicemia in an asplenic pediatric patient.

PubMed

Konda, S; Zell, D; Milikowski, C; Alonso-Llamazares, J

2013-09-01

Purpura fulminans is a rapidly progressive syndrome of small-vessel thrombosis and hemorrhagic necrosis of the skin accompanied by disseminated intravascular coagulation. We describe a case of Streptococcus pneumoniae septicemia in an asplenic 5-year-old boy on oral tacrolimus, with a past medical history of multivisceral organ transplantation and subsequent development of purpura fulminans on his chest and distal extremities. The acute infectious form of purpura fulminans is usually caused by gram-negative bacteria. Cases secondary to gram-positive encapsulated bacteria usually occur when individuals are immuno-suppressed or have anatomic or functional asplenia. Our patient had both, which likely increased his susceptibility, and he responded well to antimicrobial therapy in addition to prophylactic coverage in the setting of his immunosuppression. We review the literature for similar cases due to S. pneumoniae in the pediatric population and discuss the etiology and treatment of purpura fulminans. Copyright © 2011 Elsevier España, S.L. and AEDV. All rights reserved.

Crystallization and preliminary crystallographic analysis of the transpeptidase domain of penicillin-binding protein 2B from Streptococcus pneumoniae

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

Yamada, Mototsugu, E-mail: mototsugu-yamada@meiji.co.jp; Watanabe, Takashi; Baba, Nobuyoshi

The selenomethionyl-substituted transpeptidase domain of penicillin-binding protein (PBP) 2B from S. pneumoniae was isolated from a limited proteolysis digest of the soluble form of recombinant PBP 2B and then crystallized. MAD data were collected to 2.4 Å resolution. Penicillin-binding protein (PBP) 2B from Streptococcus pneumoniae catalyzes the cross-linking of peptidoglycan precursors that occurs during bacterial cell-wall biosynthesis. A selenomethionyl (SeMet) substituted PBP 2B transpeptidase domain was isolated from a limited proteolysis digest of a soluble form of recombinant PBP 2B and then crystallized. The crystals belonged to space group P4{sub 3}2{sub 1}2, with unit-cell parameters a = b = 86.39,more » c = 143.27 Å. Diffraction data were collected to 2.4 Å resolution using the BL32B2 beamline at SPring-8. The asymmetric unit contains one protein molecule and 63.7% solvent.« less

Characterization of Spbhp-37, a Hemoglobin-Binding Protein of Streptococcus pneumoniae

PubMed Central

Romero-Espejel, María E.; Rodríguez, Mario A.; Chávez-Munguía, Bibiana; Ríos-Castro, Emmanuel; Olivares-Trejo, José de Jesús

2016-01-01

Streptococcus pneumoniae is a Gram-positive microorganism that is the cause of bacterial pneumonia, sinusitis and otitis media. This human pathogen also can cause invasive diseases such as meningitis, bacteremia and septicemia. Hemoglobin (Hb) and haem can support the growth and viability of S. pneumoniae as sole iron sources. Unfortunately, the acquisition mechanism of Hb and haem in this bacterium has been poorly studied. Previously we identified two proteins of 37 and 22 kDa as putative Hb- and haem-binding proteins (Spbhp-37 and Spbhp-22, respectively). The sequence of Spbhp-37 protein was database annotated as lipoprotein without any function or localization. Here it was immunolocalized in the surface cell by transmission electron microscopy using specific antibodies produced against the recombinant protein. The expression of Spbhp-37 was increased when bacteria were grown in media culture supplied with Hb. In addition, the affinity of Sphbp-37 for Hb was determined. Thus, in this work we are presenting new findings that attempt to explain the mechanism involved in iron acquisition of this pathogen. In the future these results could help to develop new therapy targets in order to avoid the secondary effects caused by the traditional therapies. PMID:27200302

In vitro activity of tigecycline and comparator agents against a global collection of Gram-negative and Gram-positive organisms: tigecycline Evaluation and Surveillance Trial 2004 to 2007.

PubMed

Garrison, Mark W; Mutters, Reinier; Dowzicky, Michael J

2009-11-01

The Tigecycline Evaluation and Surveillance Trial began in 2004 to monitor the in vitro activity of tigecycline and comparator agents against a global collection of Gram-negative and Gram-positive pathogens. Against Gram negatives (n = 63 699), tigecycline MIC(90)'s ranged from 0.25 to 2 mg/L for Escherichia coli, Haemophilus influenzae, Acinetobacter baumannii, Klebsiella oxytoca, Enterobacter cloacae, Klebsiella pneumoniae, and Serratia marcescens (but was > or =32 for Pseudomonas aeruginosa). Against Gram-positive organisms (n = 32 218), tigecycline MIC(90)'s were between 0.06 and 0.25 mg/L for Streptococcus pneumoniae, Enterococcus faecium, Streptococcus agalactiae, Staphylococcus aureus, and Enterococcus faecalis. The in vitro activity of tigecycline was maintained against resistant phenotypes, including multidrug-resistant A. baumannii (9.2% of isolates), extended-spectrum beta-lactamase-producing E. coli (7.0%) and K. pneumoniae (14.0%), beta-lactamase-producing H. influenzae (22.2%), methicillin-resistant S. aureus (44.5%), vancomycin-resistant E. faecium (45.9%) and E. faecalis (2.8%), and penicillin-resistant S. pneumoniae (13.8%). Tigecycline represents a welcome addition to the armamentarium against difficult to treat organisms.

Vinpocetine inhibits Streptococcus pneumoniae-induced upregulation of mucin MUC5AC expression via induction of MKP-1 phosphatase in the pathogenesis of otitis media.

PubMed

Lee, Ji-Yun; Komatsu, Kensei; Lee, Byung-Cheol; Miyata, Masanori; O'Neill Bohn, Ashley; Xu, Haidong; Yan, Chen; Li, Jian-Dong

2015-06-15

Mucin overproduction is a hallmark of otitis media (OM). Streptococcus pneumoniae is one of the most common bacterial pathogens causing OM. Mucin MUC5AC plays an important role in mucociliary clearance of bacterial pathogens. However, if uncontrolled, excessive mucus contributes significantly to conductive hearing loss. Currently, there is a lack of effective therapeutic agents that suppress mucus overproduction. In this study, we show that a currently existing antistroke drug, vinpocetine, a derivative of the alkaloid vincamine, inhibited S. pneumoniae-induced mucin MUC5AC upregulation in cultured middle ear epithelial cells and in the middle ear of mice. Moreover, vinpocetine inhibited MUC5AC upregulation by inhibiting the MAPK ERK pathway in an MKP-1-dependent manner. Importantly, ototopical administration of vinpocetine postinfection inhibited MUC5AC expression and middle ear inflammation induced by S. pneumoniae and reduced hearing loss and pneumococcal loads in a well-established mouse model of OM. Thus, these studies identified vinpocetine as a potential therapeutic agent for inhibiting mucus production in the pathogenesis of OM. Copyright © 2015 by The American Association of Immunologists, Inc.

Capsular Serotype and Antibiotic Resistance of Streptococcus pneumoniae Isolates in Two Chilean Cities

PubMed Central

Inostroza, Jaime; Trucco, Olivia; Prado, Valeria; Vinet, Ana Maria; Retamal, Gloria; Ossa, Gonzalo; Facklam, Richard R.; Sorensen, Ricardo U.

1998-01-01

We compared the incidence of nasopharyngeal colonization by Streptococcus pneumoniae, the serotypes causing mucosal and invasive diseases, and the antibiotic resistance of these strains in patients admitted to three large hospitals and children attending day care centers in two Chilean cities (Santiago and Temuco). The populations in both cities were similar in ethnic background, socioeconomic status, family size, and access to medical care. Significant differences in nasopharyngeal colonization rates, in serotypes causing infections, and in antibiotic resistance were found between the two cities. In children 0 to 2 years of age, 42% were colonized with S. pneumoniae in Santiago compared to 14% in Temuco. A total of 41 serotypes were identified in both Chilean cities studied. Six serotypes were found only in Santiago; 14 serotypes were found only in Temuco. Antibiotic-resistant serotypes 6A, 6B, 14, 19F, and 23F were detected only in Santiago. We show that important differences in the incidence of nasopharyngeal carriage, infection, and S. pneumoniae serotypes can exist in similar populations in different areas of the same country. Our findings are relevant for prevention strategies, antibiotic usage, and vaccine design. PMID:9521139

Complications of adenotonsillectomy: a case report of meningitis due to dual infection with nontypeable Haemophilus influenzae and Streptococcus pneumoniae, and a prospective study of the rate of postoperative bacteremia.

PubMed

Tanaka, Junko; Kurosaki, Tomomichi; Shimada, Akiko; Kameyama, Yumi; Mitsuda, Toshihiro; Ishiwada, Naruhiko; Kohno, Yoichi

2013-08-01

Bacterial meningitis is a rare complication of adenotonsillectomy. We present a case of meningitis due to nontypeable Haemophilus influenzae and Streptococcus pneumoniae after adenotonsillectomy. Pulsed-field gel electrophoresis patterns indicated that the oral cavity was the source of H. influenzae and S. pneumoniae isolated from the cerebrospinal fluid. BLOOD CULTURE STUDY: As bacteremia is thought to be one of the etiologies of meningitis, we prospectively investigated the rate of bacteremia as a complication of adenotonsillectomy. Of the 46 patients included in the study, mean age of five years old, 11 (24%) had positive blood cultures during the operation. H. influenzae was the commonest organism grown (seven cultures), three of seven produced beta-lactamase, followed by S. pneumoniae (one culture), H. parainfluenzae (one culture), Peptostreptococcus micros (one culture), and Veillonella spp. (one culture). The bacteria were composed of tonsil or adenoid surface cultures in eight of 11 patients (73%). We present a rare case of meningitis complicating a adenotonsillectomy procedure, in a three years old boy. Meningitis is a rare complication of adenotonsillectomy, but bacteremia which may lead to meningitis occurs frequently, as the results.

Meningitis caused by Neisseria Meningitidis, Hemophilus Influenzae Type B and Streptococcus Pneumoniae during 2005-2012 in Turkey. A multicenter prospective surveillance study.

PubMed

Ceyhan, Mehmet; Gürler, Nezahat; Ozsurekci, Yasemin; Keser, Melike; Aycan, Ahmet Emre; Gurbuz, Venhar; Salman, Nuran; Camcioglu, Yildiz; Dinleyici, Ener Cagri; Ozkan, Sengul; Sensoy, Gulnar; Belet, Nursen; Alhan, Emre; Hacimustafaoglu, Mustafa; Celebi, Solmaz; Uzun, Hakan; Faik Oner, Ahmet; Kurugol, Zafer; Ali Tas, Mehmet; Aygun, Denizmen; Karadag Oncel, Eda; Celik, Melda; Yasa, Olcay; Akin, Fatih; Coşkun, Yavuz

2014-01-01

Successful vaccination policies for protection from bacterial meningitis are dependent on determination of the etiology of bacterial meningitis. Cerebrospinal fluid (CSF) samples were obtained prospectively from children from 1 month to ≤18 years of age hospitalized with suspected meningitis, in order to determine the etiology of meningitis in Turkey. DNA evidence of Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae), and Hemophilus influenzae type b (Hib) was detected using multiplex polymerase chain reaction (PCR). In total, 1452 CSF samples were evaluated and bacterial etiology was determined in 645 (44.4%) cases between 2005 and 2012; N. meningitidis was detected in 333 (51.6%), S. pneumoniae in 195 (30.2%), and Hib in 117 (18.1%) of the PCR positive samples. Of the 333 N. meningitidis positive samples 127 (38.1%) were identified as serogroup W-135, 87 (26.1%) serogroup B, 28 (8.4%) serogroup A and 3 (0.9%) serogroup Y; 88 (26.4%) were non-groupable. As vaccines against the most frequent bacterial isolates in this study are available and licensed, these results highlight the need for broad based protection against meningococcal disease in Turkey.

Control of transcription elongation by GreA determines rate of gene expression in Streptococcus pneumoniae.

PubMed

Yuzenkova, Yulia; Gamba, Pamela; Herber, Martijn; Attaiech, Laetitia; Shafeeq, Sulman; Kuipers, Oscar P; Klumpp, Stefan; Zenkin, Nikolay; Veening, Jan-Willem

2014-01-01

Transcription by RNA polymerase may be interrupted by pauses caused by backtracking or misincorporation that can be resolved by the conserved bacterial Gre-factors. However, the consequences of such pausing in the living cell remain obscure. Here, we developed molecular biology and transcriptome sequencing tools in the human pathogen Streptococcus pneumoniae and provide evidence that transcription elongation is rate-limiting on highly expressed genes. Our results suggest that transcription elongation may be a highly regulated step of gene expression in S. pneumoniae. Regulation is accomplished via long-living elongation pauses and their resolution by elongation factor GreA. Interestingly, mathematical modeling indicates that long-living pauses cause queuing of RNA polymerases, which results in 'transcription traffic jams' on the gene and thus blocks its expression. Together, our results suggest that long-living pauses and RNA polymerase queues caused by them are a major problem on highly expressed genes and are detrimental for cell viability. The major and possibly sole function of GreA in S. pneumoniae is to prevent formation of backtracked elongation complexes. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Meningitis caused by Neisseria Meningitidis, Hemophilus Influenzae Type B and Streptococcus Pneumoniae during 2005–2012 in Turkey

PubMed Central

Ceyhan, Mehmet; Gürler, Nezahat; Ozsurekci, Yasemin; Keser, Melike; Aycan, Ahmet Emre; Gurbuz, Venhar; Salman, Nuran; Camcioglu, Yildiz; Dinleyici, Ener Cagri; Ozkan, Sengul; Sensoy, Gulnar; Belet, Nursen; Alhan, Emre; Hacimustafaoglu, Mustafa; Celebi, Solmaz; Uzun, Hakan; Faik Oner, Ahmet; Kurugol, Zafer; Ali Tas, Mehmet; Aygun, Denizmen; Oncel, Eda Karadag; Celik, Melda; Yasa, Olcay; Akin, Fatih; Coşkun, Yavuz

2014-01-01

Successful vaccination policies for protection from bacterial meningitis are dependent on determination of the etiology of bacterial meningitis. Cerebrospinal fluid (CSF) samples were obtained prospectively from children from 1 month to ≤ 18 years of age hospitalized with suspected meningitis, in order to determine the etiology of meningitis in Turkey. DNA evidence of Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae), and Hemophilus influenzae type b (Hib) was detected using multiplex polymerase chain reaction (PCR). In total, 1452 CSF samples were evaluated and bacterial etiology was determined in 645 (44.4%) cases between 2005 and 2012; N. meningitidis was detected in 333 (51.6%), S. pneumoniae in 195 (30.2%), and Hib in 117 (18.1%) of the PCR positive samples. Of the 333 N. meningitidis positive samples 127 (38.1%) were identified as serogroup W-135, 87 (26.1%) serogroup B, 28 (8.4%) serogroup A and 3 (0.9%) serogroup Y; 88 (26.4%) were non-groupable. As vaccines against the most frequent bacterial isolates in this study are available and licensed, these results highlight the need for broad based protection against meningococcal disease in Turkey. PMID:25483487

21 CFR 520.2170 - Sulfabromomethazine sodium boluses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... pneumonia and bovine respiratory disease complex (shipping fever complex) associated with Pasteurella spp.; acute metritis and acute mastitis caused by Streptococcus spp. (3) Limitations. Administer orally...

An outbreak of penicillin resistant Streptococcus pneumoniae investigated by a polymerase chain reaction based genotyping method.

PubMed Central

Gillespie, S H; McHugh, T D; Hughes, J E; Dickens, A; Kyi, M S; Kelsey, M

1997-01-01

AIMS: To characterise the genotypes of penicillin resistant Streptococcus pneumoniae infecting patients in a care of the elderly ward and to study its transmission in a hospital environment. METHODS: Isolates of S pneumoniae were cultured from specimens obtained from patients who had been admitted to a care of the elderly ward where an outbreak had occurred. Penicillin resistant S pneumoniae were also obtained from a series of surveillance throat swabs taken from patients in the same ward. In addition, all penicillin resistant S pneumoniae isolated from specimens submitted for culture at the time of the outbreak were included. Four sensitive strains isolated from a routine microbiology laboratory were included as controls. A simple polymerase chain reaction (PCR) based genotyping method for the penicillin binding protein (PBP) genes 1a, 2x, and 2b was used to characterise the genotypes. RESULTS: Nine patients were infected with serotype 9 S pneumoniae. Four of these patients died; two deaths were directly attributable to the infection. Tested against a battery of haemolytic streptococci and other organisms found in the respiratory tract, only two false positive reactions for PBP 2x were found among S mitis. The method demonstrated that the outbreak strain had altered PBP 1a, 2b, and 2x genes, a pattern clearly distinguishable from other penicillin resistant strains isolated at the same time. CONCLUSIONS: This method is simple to perform and would enable many laboratories to characterise the genotype of penicillin resistant S pneumoniae and investigate transmission in their hospitals. Images PMID:9462268

Epigallocatechin gallate inhibits Streptococcus pneumoniae virulence by simultaneously targeting pneumolysin and sortase A.

PubMed

Song, Meng; Teng, Zihao; Li, Meng; Niu, Xiaodi; Wang, Jianfeng; Deng, Xuming

2017-10-01

Streptococcus pneumoniae (pneumococcus), the causative agent of several human diseases, possesses numerous virulence factors associated with pneumococcal infection and pathogenesis. Pneumolysin (PLY), an important virulence factor, is a member of the cholesterol-dependent cytolysin family and has cytolytic activity. Sortase A (SrtA), another crucial pneumococcal virulence determinate, contributes greatly to the anchoring of many virulence-associated surface proteins to the cell wall. In this study, epigallocatechin gallate (EGCG), a natural compound with little known antipneumococcal activity, was shown to directly inhibit PLY-mediated haemolysis and cytolysis by blocking the oligomerization of PLY and simultaneously reduce the peptidase activity of SrtA. The biofilm formation, production of neuraminidase A (NanA, the pneumococcal surface protein anchored by SrtA), and bacterial adhesion to human epithelial cells (Hep2) were inhibited effectively when S. pneumoniae D39 was cocultured with EGCG. The results from molecular dynamics simulations and mutational analysis confirmed the interaction of EGCG with PLY and SrtA, and EGCG binds to Glu277, Tyr358, and Arg359 in PLY and Thr169, Lys171, and Phe239 in SrtA. In vivo studies further demonstrated that EGCG protected mice against S. pneumoniae pneumonia. Our results imply that EGCG is an effective inhibitor of both PLY and SrtA and that an antivirulence strategy that directly targets PLY and SrtA using EGCG is a promising therapeutic option for S. pneumoniae pneumonia. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Influenza A Virus Infection Predisposes Hosts to Secondary Infection with Different Streptococcus pneumoniae Serotypes with Similar Outcome but Serotype-Specific Manifestation.

PubMed

Sharma-Chawla, Niharika; Sender, Vicky; Kershaw, Olivia; Gruber, Achim D; Volckmar, Julia; Henriques-Normark, Birgitta; Stegemann-Koniszewski, Sabine; Bruder, Dunja

2016-12-01

Influenza A virus (IAV) and Streptococcus pneumoniae are major causes of respiratory tract infections, particularly during coinfection. The synergism between these two pathogens is characterized by a complex network of dysregulated immune responses, some of which last until recovery following IAV infection. Despite the high serotype diversity of S. pneumoniae and the serotype replacement observed since the introduction of conjugate vaccines, little is known about pneumococcal strain dependency in the enhanced susceptibility to severe secondary S. pneumoniae infection following IAV infection. Thus, we studied how preinfection with IAV alters host susceptibility to different S. pneumoniae strains with various degrees of invasiveness using a highly invasive serotype 4 strain, an invasive serotype 7F strain, and a carrier serotype 19F strain. A murine model of pneumococcal coinfection during the acute phase of IAV infection showed a significantly increased degree of pneumonia and mortality for all tested pneumococcal strains at otherwise sublethal doses. The incidence and kinetics of systemic dissemination, however, remained bacterial strain dependent. Furthermore, we observed strain-specific alterations in the pulmonary levels of alveolar macrophages, neutrophils, and inflammatory mediators ultimately affecting immunopathology. During the recovery phase following IAV infection, bacterial growth in the lungs and systemic dissemination were enhanced in a strain-dependent manner. Altogether, this study shows that acute IAV infection predisposes the host to lethal S. pneumoniae infection irrespective of the pneumococcal serotype, while the long-lasting synergism between IAV and S. pneumoniae is bacterial strain dependent. These results hold implications for developing tailored therapeutic treatment regimens for dual infections during future IAV outbreaks. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Whole Exome Sequencing Identifies New Host Genomic Susceptibility Factors in Empyema Caused by Streptococcus pneumoniae in Children: A Pilot Study.

PubMed

Salas, Antonio; Pardo-Seco, Jacobo; Barral-Arca, Ruth; Cebey-López, Miriam; Gómez-Carballa, Alberto; Rivero-Calle, Irene; Pischedda, Sara; Currás-Tuala, María-José; Amigo, Jorge; Gómez-Rial, José; Martinón-Torres, Federico

2018-05-03

Pneumonia is the leading cause of death amongst infectious diseases. Streptococcus pneumoniae is responsible for about 25% of pneumonia cases worldwide, and it is a major cause of childhood mortality. We carried out a whole exome sequencing (WES) study in eight patients with complicated cases of pneumococcal pneumonia (empyema). An initial assessment of statistical association of WES variation with pneumonia was carried out using data from the 1000 Genomes Project (1000G) for the Iberian Peninsula (IBS) as reference controls. Pseudo-replication statistical analyses were carried out using different European control groups. Association tests pointed to single nucleotide polymorphism (SNP) rs201967957 (gene MEIS1 ; chromosome 2; p -value IBS = 3.71 × 10 -13 ) and rs576099063 (gene TSPAN15 ; chromosome 10; p -value IBS = 2.36 × 10 -8 ) as the best candidate variants associated to pneumococcal pneumonia. A burden gene test of pathogenicity signaled four genes, namely, OR9G9 , MUC6 , MUC3A and APOB , which carry significantly increased pathogenic variation when compared to controls. By analyzing various transcriptomic data repositories, we found strong supportive evidence for the role of MEIS1, TSPAN15 and APOBR (encoding the receptor of the APOB protein) in pneumonia in mouse and human models. Furthermore, the association of the olfactory receptor gene OR9G9 has recently been related to some viral infectious diseases, while the role of mucin genes ( MUC6 and MUC3A ), encoding mucin glycoproteins, are well-known factors related to chronic obstructive airway disease. WES emerges as a promising technique to disentangle the genetic basis of host genome susceptibility to infectious respiratory diseases.

History of macrolide use in pediatrics.

PubMed

Klein, J O

1997-04-01

Erythromycin, the prototypical macrolide, has been widely used since the 1950s in the management of pediatric infections. Erythromycin is the drug of choice for infants and children with Legionnaire's disease, pertussis, diphtheria, lower respiratory tract infections caused by Mycoplasma pneumoniae, Chlamydia pneumoniae and Chlamydia trachomatis and enteritis caused by Campylobacter jejuni. It is also indicated for treatment of syphilis; for streptococcal, staphylococcal and pneumococcal infections; genital infections caused by Ureaplasma urealyticum; and for the prevention of rheumatic fever and endocarditis in patients who are allergic to beta-lactam antibiotics. The new macrolides azithromycin and clarithromycin are also active against Borrelia burgdorferi, Helicobacter pylori, Mycobacterium avium-intracellulare complex, Cryptosporidium spp. and Toxoplasma gondii. Erythromycin is associated with a low risk of serious side effects, although gastric distress occurs in a significant proportion of patients. Drug interactions with theophylline, carbamazepine, warfarin, cyclosporine, terfenadine and digoxin limit erythromycin use. The newer macrolides azithromycin and clarithromycin are more stable, better absorbed and better tolerated than erythromycin. Azithromycin is more active than erythromycin against Haemophilus influenzae. Excellent tissue and intracellular penetration may contribute to their clinical efficacy. In children both azithromycin and clarithromycin are indicated for acute otitis media caused by Streptococcus pneumoniae, H. influenzae and Moraxella catarrhalis and for pharyngitis/tonsillitis caused by Streptococcus pyogenes. (As of December, 1996, azithromycin for oral suspension was approved for community-acquired pneumonia in children caused by C. pneumoniae, H. influenzae, M. pneumoniae and S. pneumoniae.) Claritromycin is also indicated for acute maxillary sinusitis, uncomplicated skin and skin structure infections, pneumonia and disseminated mycobacterial infections. Azithromycin and clarithromycin are associated with a lower incidence of gastrointestinal side effects, a low rate of drug discontinuation caused by side effects and a low potential for interaction with other drugs.

Interaction between Streptococcus pneumoniae and Staphylococcus aureus in paediatric patients suffering from an underlying chronic disease.

PubMed

Esposito, Susanna; Marseglia, Gian Luigi; Colombo, Carla; Iughetti, Lorenzo; Terranova, Leonardo; Ierardi, Valentina; Gambino, Monia; Principi, Nicola

2015-12-01

Little is known about the interaction between Streptococcus pneumoniae and Staphylococcus aureus in school-age children and adolescents suffering from an underlying chronic disease. To increase our knowledge in this regard, an oropharyngeal swab was obtained from school-age children and adolescents suffering from asthma (n = 423), cystic fibrosis (CF) (n = 212) and type 1 diabetes mellitus (DM1) (n = 296). S. pneumoniae detection and serotyping were performed using a real-time polymerase chain reaction, and S. aureus detection was performed using the RIDAGENE MRSA system. Among asthmatic, CF and DM1 patients, both pathogens were identified in 65/423 (15.4%), 21/212 (9.9%) and 62/296 (20.9%) children, respectively; S. pneumoniae alone was identified in 127/434 (30.0%), 21/212 (9.9%) and 86/296 (29.1%), respectively; S. aureus alone was identified in 58/434 (13.7%), 78/212 (36.8%) and 49/296 (16.6%), respectively. S. pneumoniae colonisation rates were higher in younger children and declined with age, whereas the frequency of S. aureus colonisation was quite similar in the different age groups. Among asthmatic and CF patients aged 6-9 years, S. aureus carriage was significantly higher in children who were positive for S. pneumoniae (P <0.05). No significant association emerged between S. aureus carriage and carriage of S. pneumoniae serotypes included in the pneumococcal conjugate vaccines (PCVs). This study shows for the first time that school-age children and adolescents with asthma, CF and DM1 are frequently colonised by S. pneumoniae and S. aureus and that no negative relationship seems to exist between these pathogens. Moreover, the supposed protection offered by PCV administration against S. aureus colonisation was not demonstrated. © The Author(s) 2015.

Whole Exome Sequencing Identifies New Host Genomic Susceptibility Factors in Empyema Caused by Streptococcus pneumoniae in Children: A Pilot Study

PubMed Central

Salas, Antonio; Barral-Arca, Ruth; Cebey-López, Miriam; Pischedda, Sara; Currás-Tuala, María-José; Gómez-Rial, José

2018-01-01

Pneumonia is the leading cause of death amongst infectious diseases. Streptococcus pneumoniae is responsible for about 25% of pneumonia cases worldwide, and it is a major cause of childhood mortality. We carried out a whole exome sequencing (WES) study in eight patients with complicated cases of pneumococcal pneumonia (empyema). An initial assessment of statistical association of WES variation with pneumonia was carried out using data from the 1000 Genomes Project (1000G) for the Iberian Peninsula (IBS) as reference controls. Pseudo-replication statistical analyses were carried out using different European control groups. Association tests pointed to single nucleotide polymorphism (SNP) rs201967957 (gene MEIS1; chromosome 2; p-valueIBS = 3.71 × 10−13) and rs576099063 (gene TSPAN15; chromosome 10; p-valueIBS = 2.36 × 10−8) as the best candidate variants associated to pneumococcal pneumonia. A burden gene test of pathogenicity signaled four genes, namely, OR9G9, MUC6, MUC3A and APOB, which carry significantly increased pathogenic variation when compared to controls. By analyzing various transcriptomic data repositories, we found strong supportive evidence for the role of MEIS1, TSPAN15 and APOBR (encoding the receptor of the APOB protein) in pneumonia in mouse and human models. Furthermore, the association of the olfactory receptor gene OR9G9 has recently been related to some viral infectious diseases, while the role of mucin genes (MUC6 and MUC3A), encoding mucin glycoproteins, are well-known factors related to chronic obstructive airway disease. WES emerges as a promising technique to disentangle the genetic basis of host genome susceptibility to infectious respiratory diseases. PMID:29751582

Novel Role for the Streptococcus pneumoniae Toxin Pneumolysin in the Assembly of Biofilms

PubMed Central

Shak, Joshua R.; Ludewick, Herbert P.; Howery, Kristen E.; Sakai, Fuminori; Yi, Hong; Harvey, Richard M.; Paton, James C.; Klugman, Keith P.; Vidal, Jorge E.

2013-01-01

ABSTRACT Streptococcus pneumoniae is an important commensal and pathogen responsible for almost a million deaths annually in children under five. The formation of biofilms by S. pneumoniae is important in nasopharyngeal colonization, pneumonia, and otitis media. Pneumolysin (Ply) is a toxin that contributes significantly to the virulence of S. pneumoniae and is an important candidate as a serotype-independent vaccine target. Having previously demonstrated that a luxS knockout mutant was unable to form early biofilms and expressed less ply mRNA than the wild type, we conducted a study to investigate the role of Ply in biofilm formation. We found that Ply was expressed in early phases of biofilm development and localized to cellular aggregates as early as 4 h postinoculation. S. pneumoniae ply knockout mutants in D39 and TIGR4 backgrounds produced significantly less biofilm biomass than wild-type strains at early time points, both on polystyrene and on human respiratory epithelial cells, cultured under static or continuous-flow conditions. Ply’s role in biofilm formation appears to be independent of its hemolytic activity, as S. pneumoniae serotype 1 strains, which produce a nonhemolytic variant of Ply, were still able to form biofilms. Transmission electron microscopy of biofilms grown on A549 lung cells using immunogold demonstrated that Ply was located both on the surfaces of pneumococcal cells and in the extracellular biofilm matrix. Altogether, our studies demonstrate a novel role for pneumolysin in the assembly of S. pneumoniae biofilms that is likely important during both carriage and disease and therefore significant for pneumolysin-targeting vaccines under development. PMID:24023386

Patterns of isolation of common gram positive bacterial pathogens and their susceptibilities to antimicrobial agents in Jimma Hospital.

PubMed

Gebreselassie, Solomon

2002-04-01

Gram positive bacteria are frequently emerging as antibiotic resistant pathogens, causing serious infections than ever before in the ill and debilitated patients. The pattern of isolation and the antimicrobial susceptibilities of common Gram positive cocci including Staphylococcus aureus, coagulase negative staphylococcus (CoNS), Streptococcus pyogenes, Enterococcus species and Streptococcus pneumoniae was investigated between January 1997 and June 2000 in Jimma Hospital. Of the 500 specimens collected from children and adults, 116 (23.2%) consisted of one or more of the above organisms. The following strains: Staphylococcus aureus, 47 (40.5%), CoNS, 36 (31.0%), Streptococcus pneumoniae, 26 (22.4%) Streptococcus pyogenes, 5 (4.3%) and Streptococcus faecalis, 2(1.7%) were isolated from different specimens including pus, sputum, urine, stool, blood and oro/nasopharyngeal swabs of patients. The in vitro activities of 14 different antibiotics including penicillin G, ampicillin, cloxacillin, cephalothin, gentamicin, kanamycin, tetracycline, chloramphenicol, erythromycin, trimethoprim-sulfamethoxazole, streptomycin, methicillin, vancomycin and clindamycin was determined against the clinical bacterial isolates. The antimicrobial activities were evaluated by agar diffusion technique using Mueller-Hinton agar according to NCCLS recommendations. The majority of the pathogens, 59(50.9%) were recovered from upper respiratory tract infections and 17 (14.6%) from the lower respiratory tract. The resistance patterns of S. aureus, CoNS, S. pneumoniae and enterococci to penicillin was 91.5%, 94.4%, 7.7% and 100% respectively. Penicillin, ampicillin and cloxacillin showed low effects (< 60%) on both S. aureus and CoNS. Multi-drug resistance was observed in all the gram-positive isolates, especially higher in staphylococcus species. All isolates of S. aureus (100%) were susceptible to vancomycin, clindamycin and gentamicin. In order to reduce morbidity and mortality due to antibiotic resistance susceptibility testing should be performed for the proper management of bacterial infections. This entails the need for national surveillance to monitor antibiotic resistance in bacteria by susceptibility testing using reliable methods.

Bacteriological study of dacryocystitis among patients attending in Menelik II Hospital, Addis Ababa, Ethiopia.

PubMed

Kebede, Aster; Adamu, Yilikal; Bejiga, Abebe

2010-01-01

Dacryocystitis usually results from blockage of the nasolacrimal duct. The treatment of such obstruction is surgery. There is a fivefold risk of soft tissue infection after open lacrimal surgery without systemic antibiotic prophylaxis that represents a significant risk of failure in lacrimal surgery. To determine the current bacteriology of dacryocystitis and their sensitivity to different antibiotics at Menelik II Hospital. Consecutive patients with dacryocystitis who presented to the department of ophthalmology at Menelik II Hospital between May 2004 and September 2005 were included in the study. Each patient was sent for culture and sensitivity test. Culture and sensitivity tests were obtained from Ethiopian National Health Research Institute (ENHRI), Arsho, Black Lion and Emmanuel Higher clinic laboratories. One hundred fourteen patients, 58 (50.9%) males and 56 (49.1%) females, with dacryocystitis were examined The majority of cases, 82 (71.9%), were under 30 years of age. Positive results were obtained from 91 (79.8%) patients. Gram-positive and gram negative organisms were isolated from 57 (62.6%) and 34 (37.4%) samples respectively. The five most common isolates were Streptococcus pneumoniae (23%), Streptococcus pyogens (14.3%), Staphylococcus aureus (12.1%), Streptococcus viridans (9.9%) and Haemophilus influenzae (9.9%). The antibiotics to which the majority of the isolates sensitive to were chloramphenicol (82.4%), gentamycin (79.1%), erythromycin (68.1%) and tetracycline (61.5%). While Streptococcus pneumoniae was sensitive to chloramphenicol in 95.2%. its sensitivity to tetracycline was 100%. Haemophilus influenzae was sensitive to tetracycline and chloramphenicol in 88.9% and 77.8% respectively. Gram positive organisms were the most common causes of dacryocystitis. Streptococcus pneumoniae and Haemophilus Influenza was the commonest gram positive and gram negative organisms identified respectively. Chloramphenicol and tetracycline were effective against these common organisms and are recommended for the clinical treatment of dacryocystitis.

The Human Polymeric Immunoglobulin Receptor Facilitates Invasion of Epithelial Cells by Streptococcus pneumoniae in a Strain-Specific and Cell Type-Specific Manner

PubMed Central

Brock, Sean C.; McGraw, Patricia A.; Wright, Peter F.; Crowe Jr., James E.

2002-01-01

Streptococcus pneumoniae is a gram-positive bacterial pathogen that causes invasive life-threatening disease worldwide. This organism also commonly colonizes the upper respiratory epithelium in an asymptomatic fashion. To invade, this pathogen must traverse the respiratory epithelial barrier, allowing it to cause disease locally or disseminate hematogenously throughout the body. Previous work has demonstrated that S. pneumoniae choline-binding protein A, a pneumococcal surface protein, interacts specifically with the human polymeric immunoglobulin receptor, which is expressed by cells in the respiratory epithelium. Choline-binding protein A is required for efficient colonization of the nasopharynx in vivo. Additionally, a recent study showed that the R6x laboratory strain of S. pneumoniae invades a human pharyngeal cell line in a human polymeric immunoglobulin receptor-dependent manner. These findings raised the possibility that the interaction between choline-binding protein A and human polymeric immunoglobulin receptor may be a key determinant of S. pneumoniae pathogenesis. However, the strain used in prior invasion studies, R6x, is an unencapsulated, nonpathogenic strain. In the present study we determined the relative ability of strain R6x or pathogenic strains to invade a variety of human polymeric immunoglobulin receptor-expressing epithelial cell lines. The results of this work suggest that human polymeric immunoglobulin receptor-dependent enhanced invasion of epithelial cells by S. pneumoniae is a limited phenomenon that occurs in a strain-specific and cell type-specific manner. PMID:12183558

Absence of Capsule Reveals Glycan-Mediated Binding and Recognition of Salivary Mucin MUC7 by Streptococcus pneumoniae

PubMed Central

Thamadilok, Supaporn; Roche-Håkansson, Hazeline; Håkansson, Anders P.; Ruhl, Stefan

2015-01-01

SUMMARY Salivary proteins modulate bacterial colonization in the oral cavity and interact with systemic pathogens that pass through the oropharynx. An interesting example is the opportunistic respiratory pathogen Streptococcus pneumoniae that normally resides in the nasopharynx, but belongs to the greater Mitis group of streptococci, most of which colonize the oral cavity. S. pneumoniae also expresses a serine-rich repeat (SRR) adhesin, PsrP, that is a homologue to oral Mitis group SRR adhesins, such as Hsa of S. gordonii and SrpA of S. sanguinis. Since the latter bind to salivary glycoproteins through recognition of terminal sialic acids, we wanted to determine whether S. pneumoniae also binds to salivary proteins through possibly the same mechanism. We found that only a capsule-free mutant of S. pneumoniae TIGR4 binds to salivary proteins, most prominently to mucin MUC7, but that this binding was not mediated through PsrP or recognition of sialic acid. We also found, however, that PsrP is involved in agglutination of human red blood cells (RBCs). After removal of PsrP, an additional previously masked lectin-like adhesin activity mediating agglutination of sialidase-treated RBCs becomes revealed. Using a custom-spotted glycoprotein and neoglycoprotein dot blot array, we identify candidate glycan motifs recognized by PsrP and by the putative S. pneumoniae adhesin that could perhaps be responsible for pneumococcal binding to salivary MUC7 and glycoproteins on RBCs. PMID:26172471

21 CFR 522.2260 - Sulfamethazine.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., thereafter. (2) Indications for use. For cattle for treatment of bacterial pneumonia and bovine respiratory... (Fusobacterium necrophorum), acute mastitis and acute metritis (Streptococcus spp.) when caused by one or more...

M-Ficolin Binds Selectively to the Capsular Polysaccharides of Streptococcus pneumoniae Serotypes 19B and 19C and of a Streptococcus mitis Strain

PubMed Central

Kjaer, Troels R.; Hansen, Annette G.; Sørensen, Uffe B. S.; Holm, Anne T.; Sørensen, Grith L.; Jensenius, Jens C.

2013-01-01

The three human ficolins (H-, L-, and M-ficolins) and mannan-binding lectin are pattern recognition molecules of the innate immune system mediating activation of the lectin pathway of the complement system. These four human proteins bind to some microorganisms and may be involved in the resolution of infections. We investigated binding selectivity by examining the binding of M-ficolin to a panel of more than 100 different streptococcal strains (Streptococcus pneumoniae and Streptococcus mitis), each expressing distinct polysaccharide structures. M-ficolin binding was observed for three strains only: strains of the pneumococcal serotypes 19B and 19C and a single S. mitis strain expressing a similar polysaccharide structure. The bound M-ficolin, in association with MASP-2, mediated the cleavage of complement factor C4. Binding to the bacteria was inhibitable by N-acetylglucosamine, indicating that the interaction with the bacterial surface takes place via the fibrinogen-like domain. The common N-acetylmannosamine residue present in the structures of the four capsular polysaccharides of group 19 is linked via a phosphodiester bond. This residue is apparently not a ligand for M-ficolin, since the lectin binds to two of the group 19 polysaccharides only. M-ficolin bound strongly to serotype 19B and 19C polysaccharides. In contrast to those of serotypes 19A and 19F, serotype 19B and 19C polysaccharides contain an extra N-acetylmannosamine residue linked via glycoside linkage only. Thus, this extra residue seems to be the M-ficolin ligand. In conclusion, we were able to demonstrate specific binding of M-ficolin to some capsular polysaccharides of the opportunistic pathogen S. pneumoniae and of the commensal bacterium S. mitis. PMID:23184524

Vaccination in Southeast Asia--reducing meningitis, sepsis and pneumonia with new and existing vaccines.

PubMed

Richardson, Alice; Morris, Denise E; Clarke, Stuart C

2014-07-16

Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis are leading causes of vaccine-preventable diseases such as meningitis, sepsis and pneumonia. Although there has been much progress in the introduction of vaccines against these pathogens, access to vaccines remains elusive in some countries. This review highlights the current S. pneumoniae, H. influenzae type b, and N. meningitidis immunization schedules in the 10 countries belonging to the Association of Southeast Asian Nations (ASEAN). Epidemiologic studies may be useful for informing vaccine policy in these countries, particularly when determining the cost-effectiveness of introducing new vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gene expression platform for synthetic biology in the human pathogen Streptococcus pneumoniae.

PubMed

Sorg, Robin A; Kuipers, Oscar P; Veening, Jan-Willem

2015-03-20

The human pathogen Streptococcus pneumoniae (pneumococcus) is a bacterium that owes its success to complex gene expression regulation patterns on both the cellular and the population level. Expression of virulence factors enables a mostly hazard-free presence of the commensal, in balance with the host and niche competitors. Under specific circumstances, changes in this expression can result in a more aggressive behavior and the reversion to the invasive form as pathogen. These triggering conditions are very difficult to study due to the fact that environmental cues are often unknown or barely possible to simulate outside the host (in vitro). An alternative way of investigating expression patterns is found in synthetic biology approaches of reconstructing regulatory networks that mimic an observed behavior with orthogonal components. Here, we created a genetic platform suitable for synthetic biology approaches in S. pneumoniae and characterized a set of standardized promoters and reporters. We show that our system allows for fast and easy cloning with the BglBrick system and that reliable and robust gene expression after integration into the S. pneumoniae genome is achieved. In addition, the cloning system was extended to allow for direct linker-based assembly of ribosome binding sites, peptide tags, and fusion proteins, and we called this new generally applicable standard "BglFusion". The gene expression platform and the methods described in this study pave the way for employing synthetic biology approaches in S. pneumoniae.

Interferon-γ from Brain Leukocytes Enhances Meningitis by Type 4 Streptococcus pneumoniae

PubMed Central

Pettini, Elena; Fiorino, Fabio; Cuppone, Anna Maria; Iannelli, Francesco; Medaglini, Donata; Pozzi, Gianni

2015-01-01

Streptococcus pneumoniae is the leading cause of bacterial meningitis. Pneumococcal meningitis is a life-threatening disease with high rates of mortality and neurological sequelae. Immune targeting of S. pneumoniae is essential for clearance of infection; however, within the brain, the induced inflammatory response contributes to pathogenesis. In this study we investigate the local inflammatory response and the role of IFN-γ in a murine model of pneumococcal meningitis induced by intracranial injection of type 4 S. pneumoniae. Lymphoid and myeloid cell populations involved in meningitis, as well as cytokine gene expression, were investigated after infection. Animals were treated with a monoclonal antibody specific for murine IFN-γ to evaluate its role in animal survival. Intracranial inoculation of 3 × 104 colony-forming units of type 4 strain TIGR4 caused 75% of mice to develop meningitis within 4 days. The amount of lymphocytes, NK cells, neutrophils, monocytes and macrophages in the brain increased 48 h post infection. IFN-γ mRNA levels were about 240-fold higher in brains of infected mice compared to controls. Pro-inflammatory cytokines such as IL-1β and TNF-α, and TLR2 were also upregulated. In vivo treatment with anti-IFN-γ antibody increased survival of infected mice. This study shows that IFN-γ produced during meningitis by type 4 S. pneumoniae enhances bacterial pathogenesis exerting a negative effect on the disease outcome. PMID:26648922

Characterization of Streptococcus pneumoniae isolates from Austrian companion animals and horses.

PubMed

Ginders, Maximilian; Leschnik, Michael; Künzel, Frank; Kampner, Doris; Mikula, Claudia; Steindl, Georg; Eichhorn, Inga; Feßler, Andrea T; Schwarz, Stefan; Spergser, Joachim; Loncaric, Igor

2017-11-14

The aim of the present study was to investigate the genetic relatedness and the antimicrobial resistance profiles of a collection of Austrian Streptococcus pneumoniae isolates from companion animals and horses. A total of 12 non-repetitive isolates presumptively identified as S. pneumoniae were obtained during routinely diagnostic activities between March 2009 and January 2017. Isolates were confirmed as S. pneumoniae by bile solubility and optochin susceptibility testing, matrix-assisted laser desorption-ionization-time of flight (MALDI-TOF) mass spectrometry and sequence analysis of a part recA and the 16S rRNA genes. Isolates were further characterized by pneumolysin polymerase chain reaction (PCR) and genotyped by multilocus sequence typing (MLST). Antimicrobial susceptibility testing was performed and resistance genes were detected by specific PCR assays. All isolates were serotyped. Four sequence types (ST) (ST36, ST3546, ST6934 and ST6937) and four serotypes (3, 19A, 19F and 23F) were detected. Two isolates from twelve displayed a multidrug-resistance pheno- and genotype. This study represents the first comprehensive investigation on characteristics of S. pneumoniae isolates recovered from Austrian companion animals and horses. The obtained results indicate that common human sero- (23F) and sequence type (ST36) implicated in causing invasive pneumococcal disease (IPD) may circulate in dogs. Isolates obtained from other examined animals seem to be host-adapted.

Streptococcus pneumoniae oropharyngeal colonization in children and adolescents with cystic fibrosis.

PubMed

Esposito, Susanna; Colombo, Carla; Tosco, Antonella; Montemitro, Enza; Volpi, Sonia; Ruggiero, Luca; Lelii, Mara; Bisogno, Arianna; Pelucchi, Claudio; Principi, Nicola

2016-05-01

This study was designed to evaluate Streptococcus pneumoniae (S. pneumoniae) carriage rates in patients with cystic fibrosis (CF). An oropharyngeal swab was obtained from 212 CF children and adolescents enrolled during routine clinical visits. DNA from swabs was analyzed by real-time polymerase chain reaction. A total of 42 (19.8%) CF patients (mean age±standard deviation [SD], 12.0±3.3years) were colonized by S. pneumoniae. Carriage was more common in younger patients and tended to decline with age. Administration of systemic and/or inhaled antibiotics in the last 3months significantly correlated with a reduced carrier state [odds ratio (OR) 0.23, 95% confidence interval (CI) 0.07-0.69, and OR 0.26, 95% CI 0.08-0.77, respectively]. Vitamin D serum levels ≥30ng/mL were less common in carriers than that in non-carriers (OR 0.35; 95% CI 0.08-1.49). In both the vaccinated and unvaccinated subjects, serotypes 19F, 5, 4, and 9V were the most commonly carried serotypes. S. pneumoniae carrier state of school-age children and adolescents with CF is more prevalent than previously thought, and pneumococcal conjugate vaccination administered in the first year of life does not reduce the risk of re-colonization in later childhood and adolescence. Copyright © 2015. Published by Elsevier B.V.

[Assessment of two DNA extraction methods to amplify the pneumolysin gene (PLY) from blood culture samples of Streptococcus pneumoniae].

PubMed

Hernández, Carolina; Durán, Claudia; Ulloa, María Teresa; Prado, Valeria

2004-05-01

Streptococcus pneumoniae is a common etiologic agent of invasive respiratory infections among children under 5 years of age and older adults. Isolation rates of S. pneumoniae by traditional culture techniques are low. To study the sensitivity and specificity of two different DNA extraction methods to amplify the ply gene, applied to three different types of blood culture broths, experimentally inoculated with S. pneumoniae. DNA was extracted from the cultures using an organic method or a technique that consists in dilution, washing with NaOH and concentration of the sample. This was followed by PCR amplification of a 355 pb fragment of the pneumolysin gene (ply). The organic DNA extraction method inhibited the PCR reaction at all concentrations studied (0.6 to 10(6) colony forming units/mL). Using the NaOH extraction, ply gene amplification was positive in all three blood culture broths, but only at concentrations of 10(3) colony forming units/mL, or higher. Using the same DNA extraction method, PCR was negative when the broths were inoculated with seven other related bacterial species, which results in a 100% specificity. Detection of S. pneumoniae by amplification of ply gene from blood cultures using the protocol of NaOH for DNA extraction is specific and provides results in a short lapse. However, the diagnostic sensitivity is not optimal, which limits its clinical use.

Human Antibodies to PhtD, PcpA, and Ply Reduce Adherence to Human Lung Epithelial Cells and Murine Nasopharyngeal Colonization by Streptococcus pneumoniae

PubMed Central

Kaur, Ravinder; Surendran, Naveen; Ochs, Martina

2014-01-01

Streptococcus pneumoniae adherence to human epithelial cells (HECs) is the first step in pathogenesis leading to infections. We sought to determine the role of human antibodies against S. pneumoniae protein vaccine candidates PhtD, PcpA, and Ply in preventing adherence to lung HECs in vitro and mouse nasopharyngeal (NP) colonization in vivo. Human anti-PhtD, -PcpA, and -Ply antibodies were purified and Fab fragments generated. Fabs were used to test inhibition of adherence of TIGR4 and nonencapsulated strain RX1 to A549 lung HECs. The roles of individual proteins in adherence were tested using isogenic mutants of strain TIGR4. Anti-PhtD, -PcpA, and -Ply human antibodies were assessed for their ability to inhibit NP colonization in vivo by passive transfer of human antibody in a murine model. Human antibodies generated against PhtD and PcpA caused a decrease in adherence to A549 cells (P < 0.05). Anti-PhtD but not anti-PcpA antibodies showed a protective role against mouse NP colonization. To our surprise, anti-Ply antibodies also caused a significant (P < 0.05) reduction in S. pneumoniae colonization. Our results support the potential of PhtD, PcpA, and Ply protein vaccine candidates as alternatives to conjugate vaccines to prevent non-serotype-specific S. pneumoniae colonization and invasive infection. PMID:25245804

N-acetylglucosamine-Mediated Expression of nagA and nagB in Streptococcus pneumoniae.

PubMed

Afzal, Muhammad; Shafeeq, Sulman; Manzoor, Irfan; Henriques-Normark, Birgitta; Kuipers, Oscar P

2016-01-01

In this study, we have explored the transcriptomic response of Streptococcus pneumoniae D39 to N-acetylglucosamine (NAG). Transcriptome comparison of S. pneumoniae D39 wild-type grown in chemically defined medium (CDM) in the presence of 0.5% NAG to that grown in the presence of 0.5% glucose revealed elevated expression of many genes/operons, including nagA, nagB, manLMN , and nanP . We have further confirmed the NAG-dependent expression of nagA, nagB, manLMN , and nanP by β-galactosidase assays. nagA, nagB and glmS are putatively regulated by a transcriptional regulator NagR. We predicted the operator site of NagR ( dre site) in P nagA , P nagB , and P glmS , which was further confirmed by mutating the predicted dre site in the respective promoters ( nagA, nagB , and glmS ). Growth comparison of Δ nagA , Δ nagB , and Δ glmS with the D39 wild-type demonstrates that nagA and nagB are essential for S. pneumoniae D39 to grow in the presence of NAG as a sole carbon source. Furthermore, deletion of ccpA shows that CcpA has no effect on the expression of nagA, nagB , and glmS in the presence of NAG in S . pneumoniae .

N-acetylglucosamine-Mediated Expression of nagA and nagB in Streptococcus pneumoniae

PubMed Central

Afzal, Muhammad; Shafeeq, Sulman; Manzoor, Irfan; Henriques-Normark, Birgitta; Kuipers, Oscar P.

2016-01-01

In this study, we have explored the transcriptomic response of Streptococcus pneumoniae D39 to N-acetylglucosamine (NAG). Transcriptome comparison of S. pneumoniae D39 wild-type grown in chemically defined medium (CDM) in the presence of 0.5% NAG to that grown in the presence of 0.5% glucose revealed elevated expression of many genes/operons, including nagA, nagB, manLMN, and nanP. We have further confirmed the NAG-dependent expression of nagA, nagB, manLMN, and nanP by β-galactosidase assays. nagA, nagB and glmS are putatively regulated by a transcriptional regulator NagR. We predicted the operator site of NagR (dre site) in PnagA, PnagB, and PglmS, which was further confirmed by mutating the predicted dre site in the respective promoters (nagA, nagB, and glmS). Growth comparison of ΔnagA, ΔnagB, and ΔglmS with the D39 wild-type demonstrates that nagA and nagB are essential for S. pneumoniae D39 to grow in the presence of NAG as a sole carbon source. Furthermore, deletion of ccpA shows that CcpA has no effect on the expression of nagA, nagB, and glmS in the presence of NAG in S. pneumoniae. PMID:27900287

Oral ofloxacin therapy for lower respiratory tract infection.

PubMed

Gentry, L O; Lipsky, B; Farber, M O; Tucker, B; Rodriguez-Gomez, G

1992-01-01

We made an open, noncomparative evaluation of ofloxacin, 400 mg orally bid for 10 days, in 98 subjects with community-acquired pneumonia or pathogen-confirmed bronchitis. Thirty-nine (40%) of the subjects were treated in the hospital and 59 (60%) were treated as outpatients. The mean age of those treated was 56.2 years; 73 (74%) of the subjects either were more than 60 years old or had a history of chronic obstructive pulmonary disease, or both. There were 95 organisms initially isolated in sputum, aspirate, or lavage fluid; all were susceptible to ofloxacin, and none acquired resistance during therapy. Haemophilus influenzae was the most common pathogen (19 isolates), followed by Streptococcus pneumoniae (18) and Staphylococcus aureus (10). Clinical responses included cure in 70 patients (71%), improvement in 26 (27%), and failure in two (2%). After 10 days of therapy, pathogens persisted in two cases; in one case, Streptococcus salivarius was isolated, though it remained susceptible to ofloxacin, and in the other, Klebsiella pneumoniae was accompanied by superinfection due to a resistant strain of Serratia marcescens. We included in this study three confirmed cases of atypical pneumonia successfully treated with ofloxacin, two of them due to Mycoplasma pneumonia and one to Legionella pneumophila. Ofloxacin was well tolerated. Our data indicate that ofloxacin is effective and safe as specific and empiric treatment for many lower respiratory tract infections.

Purulent pericarditis and pneumonia caused by Streptococcus equi subsp. zooepidemicus.

PubMed

Held, Jürgen; Schmitz, Roland; van der Linden, Mark; Nührenberg, Thomas; Häcker, Georg; Neumann, Franz-Josef

2014-02-01

Purulent pericarditis is a life-threatening disease that usually manifests following bacteraemia or through spreading from an intrathoracic focus. Only a few cases of this disease have been reported with Lancefield group C streptococci as aetiological agents, and the primary focus in these infections remains unknown. We report a case of purulent pericarditis with septic and cardiogenic shock, caused by Streptococcus equi subsp. zooepidemicus (group C) in a 51-year-old patient. The pathogen was possibly contracted through contact with horses. Most probably, it caused initially pneumonia before spreading to the pericardium, either directly or via the bloodstream. A combined therapeutic approach, consisting of antibiotic therapy and repeated pericardial drainage, was necessary to ensure a clinical cure. After discharge, long-term follow-up for development of constrictive pericarditis is considered mandatory.

[Rapid identification of meningitis due to bacterial pathogens].

PubMed

Ubukata, Kimiko

2013-01-01

We constructed a new real-time PCR method to detect causative pathogens in cerebrospinal fluid (CSF) from patient due to bacterial meningitis. The eight pathogens targeted in the PCR are Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus agalactiae, Staphylococcus aurues, Neisseria meningitides, Listeria monocytogenes, Esherichia coli, and Mycoplasma pneumoniae. The total time from DNA extraction from CSF to PCR analysis was 1.5 hour. The pathogens were detected in 72% of the CSF samples (n=115) by real-time PCR, but in only 48% by culture, although the microorganisms were completely concordant. The detection rate of pathogens with PCR was significantly better than that with cultures in patients with antibiotic administration.In conclusion, detection with real-time PCR is useful for rapidly identifying the causative pathogens of meningitis and for examining the clinical course of chemotherapy.

Group B streptococcal necrotizing pneumonia in a diabetic adult patient.

PubMed

Pacha, Andrea; Luna Cian, Ramiro; Bonofiglio, Laura; Solari, Melisa; Strada, Virginia; Suárez, Mariana; Vigliarolo, Laura; Tersigni, Carina; Mollerach, Marta; Lopardo, Horacio

The aim of this report is to describe a rare case of necrotizing pneumonia due to group B Streptococcus serotype III in a relatively young male adult (48 years old) suffering from diabetes. The organism was isolated from his pleural fluid and was only resistant to tetracycline. The patient first received ceftazidime (2g/8h i.v.)+clindamycin (300mg/8h) for 18 days and then he was discharged home and orally treated with amoxicillin clavulanic acid (1g/12h) for 23 days with an uneventful evolution. As in the cases of invasive infection by Streptococcus pyogenes, clindamycin could prevent streptococcal toxic shock syndrome. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

[Bacterial meningitis].

PubMed

Brouwer, M C; van de Beek, D

2012-05-01

Bacterial meningitis is a severe disease which affects 35.000 Europeans each year and has a mortality rate of about 20%. During the past 25 years the epidemiology of bacterial meningitis has changed significantly due to the implementation of vaccination against Haemophilus influenzae, Neisseria meningtidis group C and Streptococcus pneumoniae. Due to these vaccines, meningitis is now predominantly a disease occurring in adults, caused especially by Streptococcus pneumoniae, while it was formerly a child disease which was largely caused by Haemophilus influenzae. Bacterial meningitis is often difficult to recognize since the classical presentation with neck stiffness, reduced awareness and fever occurs in less than half of the patients. The only way to diagnose or exclude bacterial meningitis is by performing low-threshold cerebrospinal fluid examination with a suspicion of bacterial meningitis. The treatment consists of the prescription of antibiotics and dexamethasone.

Determination of Trimethoprim-Sulfamethoxazole Resistance in Streptococcus pneumoniae by Using the E Test with Mueller-Hinton Agar Supplemented with Sheep or Horse Blood May Be Unreliable

PubMed Central

Lovgren, M.; Dell’Acqua, L.; Palacio, R.; Echániz-Aviles, G.; Soto-Noguerón, A.; Castañeda, E.; Agudelo, C. I.; Heitmann, I.; Brandileone, M. C.; Zanella, R. C.; Rossi, A.; Pace, J.; Talbot, J. A.

1999-01-01

An international, multicenter study compared trimethoprim-sulfamethoxazole MICs for 743 Streptococcus pneumoniae isolates (107 to 244 isolates per country) by E test, using Mueller-Hinton agar supplemented with 5% defibrinated horse blood or 5% defibrinated sheep blood, with MICs determined by the National Committee for Clinical Laboratory Standards broth microdilution reference method. Agreement within 1 log2 dilution and minor error rates were 69.3 and 15.5%, respectively, on sheep blood-supplemented agar and 76.9 and 13.6%, respectively, with horse blood as the supplement. Significant interlaboratory variability was observed. E test may not be a reliable method for determining the resistance of pneumococci to trimethoprim-sulfamethoxazole. PMID:9854095

Capsule expression in Streptococcus mitis modulates interaction with oral keratinocytes and alters susceptibility to human antimicrobial peptides.

PubMed

Rukke, H V; Engen, S A; Schenck, K; Petersen, F C

2016-08-01

Streptococcus mitis is a colonizer of the oral cavity and the nasopharynx, and is closely related to Streptococcus pneumoniae. Both species occur in encapsulated and unencapsulated forms, but in S. mitis the role of the capsule in host interactions is mostly unknown. Therefore, the aim of this study was to examine how capsule expression in S. mitis can modulate interactions with the host with relevance for colonization. The S. mitis type strain, as well as two mutants of the type strain, an isogenic capsule deletion mutant, and a capsule switch mutant expressing the serotype 4 capsule of S. pneumoniae TIGR4, were used. Wild-type and capsule deletion strains of S. pneumoniae TIGR4 were included for comparison. We found that capsule production in S. mitis reduced adhesion to oral and lung epithelial cells. Further, exposure of oral epithelial cells to encapsulated S. mitis resulted in higher interleukin-6 and CXCL-8 transcription levels relative to the unencapsulated mutant. Capsule expression in S. mitis increased the sensitivity to human neutrophil peptide 1-3 but reduced the sensitivity to human β-defensin-3 and cathelicidin. This was in contrast with S. pneumoniae in which capsule expression has been generally associated with increased sensitivity to human antimicrobial peptides (AMPs). Collectively, these findings indicate that capsule expression in S. mitis is important in modulating interactions with epithelial cells, and is associated with increased or reduced susceptibility to AMPs depending on the nature of the AMP. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Serine Protease PrtA from Streptococcus pneumoniae Plays a Role in the Killing of S. pneumoniae by Apolactoferrin ▿

PubMed Central

Mirza, Shaper; Wilson, Landon; Benjamin, William H.; Novak, Jan; Barnes, Stephen; Hollingshead, Susan K.; Briles, David E.

2011-01-01

It is known that apolactoferrin, the iron-free form of human lactoferrin, can kill many species of bacteria, including Streptococcus pneumoniae. Lactoferricin, an N-terminal peptide of apolactoferrin, and fragments of it are even more bactericidal than apolactoferrin. In this study we found that apolactoferrin must be cleaved by a serine protease in order for it to kill pneumococci. The serine protease inhibitors were able to block killing by apolactoferrin but did not block killing by a lactoferrin-derived peptide. Thus, the killing of pneumococci by apolactoferrin appears to require a protease to release a lactoferricin-like peptide(s). Incubation of apolactoferrin with growing pneumococci resulted in a 12-kDa reduction in its molecular mass, of which about 7 to 8 kDa of the reduction was protease dependent. Capsular type 2 and 19F strains with mutations in the gene encoding the major cell wall-associated serine protease, prtA, lost much of their ability to degrade apolactoferrin and were relatively resistant to killing by apolactoferrin (P < 0.001). Recombinant PrtA was also able to cleave apolactoferrin, reducing its mass by about 8 kDa, and greatly enhance the killing activity of the solution containing the apolactoferrin and its cleavage products. Mass spectroscopy revealed that PrtA makes a major cut between amino acids 78 and 79 of human lactoferrin, removing the N-terminal end of the molecule (about 8.6 kDa). The simplest interpretation of these data is that the mechanism by which apolactoferrin kills Streptococcus pneumoniae requires the release of a lactoferricin-like peptide(s) and that it is this peptide(s), and not the intact apolactoferrin, which kills pneumococci. PMID:21422179

Comparative pharmacodynamics of the new fluoroquinolone ABT492 and levofloxacin with Streptococcus pneumoniae in an in vitro dynamic model.

PubMed

Firsov, Alexander A; Alferova, Irene V; Smirnova, Maria V; Lubenko, Irene Yu; Portnoy, Yury A; Zinner, Stephen H

2005-05-01

The kinetics of killing of Streptococcus pneumoniae exposed to ABT492 or levofloxacin were compared. S. pneumoniae ATCC 49619 and four ciprofloxacin-resistant clinical isolates, S. pneumoniae 1149, 391, 79 and 804, were exposed to ABT492 and levofloxacin as a single dose in a dynamic model that simulates human pharmacokinetics of the quinolones. With S. pneumoniae ATCC 49619 eight-fold ranging AUC/MIC ratios (60-500 h) were simulated for each quinolone. In addition, two larger AUC/MICs, i.e., 1080 and 2150 h for ABT492 and 1460 and 3660 h for levofloxacin which correspond to 100 and 200 mg doses of ABT492 and 200 and 500 mg doses of levofloxacin, respectively, were mimicked. Each ciprofloxacin-resistant organism was exposed to the clinical doses of ABT492 (400 mg) and levofloxacin (500 mg); the respective AUC/MIC ratios were from 580 to 3470 h and from 28 to 110 h. At comparable AUC/MICs (from 60 to 500 h), regrowth of S. pneumoniae ATCC 49619 followed initial killing, and the times to regrowth were longer with levofloxacin than ABT492. However, no regrowth of S. pneumoniae ATCC 49619 occurred at the higher AUC/MICs of ABT492 (1080 and 2150 h) and levofloxacin (1460 and 3660 h). Killing of S. pneumoniae 1149, 391 and 79 without bacterial regrowth, was provided by ABT492 (AUC/MIC 3470, 2310 and 1160 h, respectively) but not levofloxacin (AUC/MIC 55, 110 and 28 h, respectively). Regrowth of S. pneumoniae 804 was observed with both ABT492 and levofloxacin (AUC/MIC 580 and 55 h, respectively). Areas between the control growth curve and the time-kill curve (ABBCs) for ABT492 against S. pneumoniae 1149, 391 and 79 were 2.6-4.2 times larger than the respective ABBCs for levofloxacin, whereas similar ABBCs were found with S. pneumoniae 804 exposed to both quinolones. These findings predict significantly greater efficacy of ABT492 than levofloxacin at clinically achievable AUC/MIC ratios against ciprofloxacin-resistant S. pneumoniae and similar efficacies of the two quinolones against susceptible organisms.

Etiology of parapneumonic effusion and pleural empyema in children. The role of conventional and molecular microbiological tests.

PubMed

Krenke, Katarzyna; Sadowy, Ewa; Podsiadły, Edyta; Hryniewicz, Waleria; Demkow, Urszula; Kulus, Marek

2016-07-01

An increasing incidence of parapneumonic effusion and pleural empyema (PPE/PE) has been reported in recent studies. As only few data on etiology of PPE/PE in Central Europe have been reported, we undertook a study on the etiology of PPE/PE in children, using both standard culture and molecular techniques. This prospective study was conducted between June 2011 and December 2013. Consecutive children with PPE/PE complicating community acquired pneumonia, who required diagnostic/therapeutic thoracentesis were included. Blood and pleural fluid samples for microbiological cultures were collected. Molecular methods were applied to identify Streptococcus pneumonia, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, Mycoplasma pneumoniae, Chlamydophila pneumoniae, and respiratory viruses in pleural fluid. The study group included 64 children, median age 4 (1-15). Seven of 64 (10.9%) blood cultures and 11 of 64 (17.2%) pleural fluid cultures revealed bacterial growth. The most common bacteria detected was S. pneumoniae (13 blood and pleural fluid samples from 11/64 (17.2%) children). DNA sequences of typical bacteria were found in 29/64 (45.3%) pleural fluid samples. S. pneumoniae was identified in 90% of these samples. The most common serotypes were: serotype 6B in 9/26 (36.6%), 19A in 6/26 (23%), serotype 3 in 3/26 (11.5%), 6A and 23F (both in 2/26 i.e. 7.7%) patients. Molecular methods identified atypical bacteria in 8/58 (13.8%) and respiratory viruses in 12/58 (20.7%) pleural fluid samples. S. pneumoniae, in particular serotype 6B and 19A, is the most common etiologic agent of PPE/PE in Polish children. The use of PCR significantly improves pathogen identification in pleural fluid. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pharmacodynamics of moxifloxacin and levofloxacin against Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli: simulation of human plasma concentrations after intravenous dosage in an in vitro kinetic model.

PubMed

Odenholt, Inga; Cars, Otto

2006-11-01

To compare in an in vitro kinetic model the pharmacodynamics of moxifloxacin and levofloxacin with a concentration-time profile simulating the human free non-protein bound concentrations of 400 mg moxifloxacin intravenous (iv) once daily, 500 mg levofloxacin iv once daily and 750 mg levofloxacin iv once daily against strains of Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli with variable susceptibility to fluoroquinolones. The strains used in the study included S. pneumoniae ATCC 6306 (native strain), S. pneumoniae 19397 (double mutation; gyrA and parC), S. pneumoniae 4241 (single mutation; parC), S. aureus ATCC 13709 (native strain), S. aureus MB5 (single mutation; gyrA), E. coli M12 (single mutation; gyrA), E. coli ATCC 25922 (native strain) and K. pneumoniae ATCC 29655 (native strain). The strains were exposed to moxifloxacin and levofloxacin in an in vitro kinetic model simulating the free human serum concentration-time profile of moxifloxacin 400 mg once daily, levofloxacin 500 mg once daily and 750 mg once daily. Repeated samples were taken regularly during 24 h and viable counts were carried out. A correlation was seen between both the area under the serum concentration curve and MIC (AUC/MIC) and the peak concentration/MIC (Cmax/MIC) versus area under the bactericidal killing curve (AUBKC) or Deltalog0-24 cfu/mL. Compiling all data, an AUC/MIC of approximately 100 and a Cmax/MIC of 10 gave a maximal bactericidal effect for both levofloxacin and moxifloxacin. In accordance with the results from others, our study indicated that a lower AUC/MIC was needed for S. pneumoniae in comparison with the Gram-negative bacteria studied. Moxifloxacin yielded higher AUC/MIC and Cmax/MIC against the investigated Gram-positive bacteria in comparison with levofloxacin 500 mg once daily and 750 mg once daily.

Isolation of Streptococcus tigurinus - a novel member of Streptococcus mitis group from a case of periodontitis.

PubMed

Dhotre, Shree V; Mehetre, Gajanan T; Dharne, Mahesh S; Suryawanshi, Namdev M; Nagoba, Basavraj S

2014-08-01

Streptococcus tigurinus is a new member of the Streptococcus viridians group and is closely related to Streptococcus mitis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae, Streptococcus oralis, and Streptococcus infantis. The type strain AZ_3a(T) of S. tigurinus was originally isolated from a patient with infective endocarditis. Accurate identification of S. tigurinus is facilitated only by newer molecular methods like 16S rRNA gene analysis. During the course of study on bacteraemia and infective endocarditis with reference to periodontitis and viridians group of streptococci, a strain of S. tigurinus isolated from subgingival plaque of a patient with periodontitis identified by 16S rRNA gene analysis, which was originally identified as Streptococcus pluranimalium by Vitek 2. Confirmation by 16S rRNA gene analysis showed 99.39% similarity (1476/1485 bp) with S. tigurinus AZ_3a(T) (AORU01000002). To the best of our knowledge, this is the first report of isolation of S. tigurinus from the oral cavity of a periodontitis patient. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Nasopharyngeal swabs of school children, useful in rapid assessment of community antimicrobial resistance patterns in Streptococcus pneumoniae and Haemophilus influenzae.

PubMed

Lalitha, M K; David, Thambu; Thomas, Kurien

2013-01-01

The present study evaluates the feasibility of rapid surveillance of community antimicrobial resistance (AMR) patterns of Streptococcus pneumoniae and Haemophilus influenzae in India using nasopharyngeal swabs (NPSs) of school children. It compares the AMR data obtained with that of invasive and nasopharyngeal (NP) isolates studied previously. No one has done such surveillance since our study so we decided to publish and more clearly demonstrate the feasibility of the methodology we did. This community-based, cross-sectional, cluster sample study had seven centers; each had two sites distant to them. Two hundred sixty school children per center were enrolled. NP swabbing was performed and isolates identified as S. pneumoniae and H. influenzae at each center were sent to reference laboratories. From January to December 2004, 1,988 NP swabs were processed; 776 S. pneumoniae and 64 H. influenzae were isolated. The AMR patterns for S. pneumoniae to co-trimoxazole varied, with sensitivity as low as 6% in Mumbai, 29% in Chennai and Vellore, and 100% in Delhi and Lucknow. For H. influenzae, sensitivity rates to co-trimoxazole ranged from 22% to 62%. The AMR patterns for both bacteria in the present study with data from invasive and NP isolates studied earlier were similar. The study demonstrates that it is practical and feasible to rapidly assess the AMR patterns of both S. pneumoniae and H. influenzae in NPSs of school children in different geographic locations all over India. Copyright © 2013 Elsevier Inc. All rights reserved.

Etiology and outcome of community-acquired lung abscess.

PubMed

Takayanagi, Noboru; Kagiyama, Naho; Ishiguro, Takashi; Tokunaga, Daidou; Sugita, Yutaka

2010-01-01

Anaerobes are the first and Streptococcus species the second most common cause of community-acquired lung abscess (CALA) in the West. The etiologic pathogens of this disease have changed in Taiwan, with Klebsiella pneumoniae being reported as the most common cause of CALA. To determine the etiologies of community-acquired lung abscess. We retrospectively reviewed the records of 205 Japanese adult patients with CALA to evaluate etiologies and outcomes. We used not only traditional microbiological investigations but also percutaneous ultrasonography-guided transthoracic needle aspiration and protected specimen brushes. Of these 205 patients, 122 had documented bacteriological results, with 189 bacterial species isolated. Pure aerobic, mixed aerobic and anaerobic, and pure anaerobic bacteria were isolated in 90 (73.8%), 17 (13.9%), and 15 (12.3%) patients, respectively. The four most common etiologic pathogens were Streptococcus species (59.8%), anaerobes (26.2%), Gemella species (9.8%), and K. pneumoniae (8.2%). Streptococcus mitis was the most common among the Streptococcus species. Mean duration of antibiotic administration was 26 days. Six patients (2.9%, 3 with actinomycosis and 3 with nocardiosis) were treated with antibiotics for 76-189 days. Two patients with anaerobic lung abscess died. The first and second most common etiologic pathogens of CALA in our hospital were Streptococcus species and anaerobes, respectively. The etiologies in our study differ from those in Taiwan and are similar to those in the West with the exception that Streptococcus species were the most common etiologic pathogens in our study whereas anaerobes are the most frequent etiologic pathogens in Western countries. S. mitis and Gemella species are important etiologic pathogens as well. The identification of Actinomyces and Nocardia is important in order to define the adequate duration of antibiotic administration. Copyright 2010 S. Karger AG, Basel.

Recombinant plasmids for encoding restriction enzymes DpnI and DpnII of streptococcus pneumontae

DOEpatents

Lacks, Sanford A.

1990-01-01

Chromosomal DNA cassettes containing genes encoding either the DpnI or DpnII restriction endonucleases from Streptococcus pneumoniae are cloned into a streptococcal vector, pLS101. Large amounts of the restriction enzymes are produced by cells containing the multicopy plasmids, pLS202 and pLS207, and their derivatives pLS201, pLS211, pLS217, pLS251 and pLS252.

Influenza-like Illness Surveillance on the California-Mexico Border, 2004-2009

DTIC Science & Technology

2011-01-01

common in all age groups, causing both hospital- and community - acquired epidemics. AdV probably accounts for 3% of the infections in the civilian...enterovirus, herpes simplex virus, Streptococcus pneumoniae , and Streptococcus pyogenes. Conclusions The US-Mexico border is one of the busiest in...countries where ARIs are the cause of up to 25% of all pediatric deaths.3 In Mexico, ARIs are the leading cause of disease (http://www.dged

Recombinant plasmids for encoding restriction enzymes DpnI and DpnII of Streptococcus pneumontae

DOEpatents

Lacks, S.A.

1990-10-02

Chromosomal DNA cassettes containing genes encoding either the DpnI or DpnII restriction endonucleases from Streptococcus pneumoniae are cloned into a streptococcal vector, pLS101. Large amounts of the restriction enzymes are produced by cells containing the multicopy plasmids, pLS202 and pLS207, and their derivatives pLS201, pLS211, pLS217, pLS251 and pLS252. 9 figs.

Population-based incidence of invasive haemophilus influenzae and pneumococcal diseases before the introduction of vaccines in Japan.

PubMed

Nakamura, Riko; Togashi, Takehiro

2013-12-01

Before the introduction of vaccines, the incidence of bacterial meningitis among children aged 28 days to 5 years was 8.48, Haemophilus influenzae type-b meningitis was 5.65 and Streptococcus pneumoniae meningitis was 1.85 per 100,000 person-years in Hokkaido, Japan. The incidence of bacteremia caused by S. pneumoniae was 60.15 and H. influenzae was 18.80.

Contract Support and Facilitation of Epidemic Outbreak Surveillance (EOS) Program Final Operating Capability (FOC)

DTIC Science & Technology

2007-08-01

Community Acquired Pneumonia . The principal investigator is William Weisburg, Ph.D. of Nanogen, and the Medical College of Wisconsin (MCW) is a...captures the most important viruses involved in community - acquired respiratory infections: 1. Influenza A (fluA) 2. Influenza B (fluB) 3. Respiratory...Adenovirus subtype 4, Human Parainfluenza Virus 1, Human Parainfluenza Virus 2, Human Parainfluenza Virus 3, Human Metapneumovirus, Streptococcus pneumonia

Serotype Distribution and Antibiotic Susceptibility of Streptococcus pneumoniae Strains Carried by Children Infected with Human Immunodeficiency Virus

PubMed Central

Safari, Dodi; Kurniati, Nia; Waslia, Lia; Khoeri, Miftahuddin Majid; Putri, Tiara; Bogaert, Debby; Trzciński, Krzysztof

2014-01-01

Abstract Background We studied the serotype distribution and antibiotic susceptibility of Streptococcus pneumoniae isolates carried by children infected with HIV in Jakarta, Indonesia. Methods Nasopharyngeal swabs were collected from 90 HIV infected children aged 4 to 144 months. S. pneumoniae was identified by conventional and molecular methods. Serotyping was performed with sequential multiplex PCR and antibiotic susceptibility with the disk diffusion method. Results We identified S. pneumoniae carriage in 41 children (46%). Serotype 19F was most common among 42 cultured strains (19%) followed by 19A and 6A/B (10% each), and 23F (7%). Most isolates were susceptible to chloramphenicol (86%), followed by clindamycin (79%), erythromycin (76%), tetracycline (43%), and sulphamethoxazole/trimethoprim (41%). Resistance to penicillin was most common with only 33% of strains being susceptible. Strains of serotypes targeted by the 13-valent pneumococcal conjugate polysaccharide vaccine (PCV13) were more likely to be multidrug resistant (13 of 25 or 52%) compared to non-PCV13 serotype isolates (3 of 17 or 18%; Fisher exact test p = 0.05). Conclusion Our study provides insight into the epidemiology of pneumococcal carriage in young HIV patients in Indonesia. These findings may facilitate potential preventive strategies that target invasive pneumococcal disease in Indonesia. PMID:25343448

Prevalence of penicillin and erythromycin resistance among invasive Streptococcus pneumoniae isolates reported by laboratories in the southern and eastern Mediterranean region.

PubMed

Borg, M A; Tiemersma, E; Scicluna, E; van de Sande-Bruinsma, N; de Kraker, M; Monen, J; Grundmann, H

2009-03-01

Information about the epidemiology of resistance in Streptococcus pneumoniae within southern and eastern countries of the Mediterranean region is incomplete, as reports have been sporadic and difficult to compare. Over a 36-month period, from 2003 to 2005, the ARMed project collected 1298 susceptibility test results of invasive isolates of S. pneumoniae from blood and spinal fluid cultures routinely processed within 59 participating laboratories situated in Algeria, Cyprus, Egypt, Jordan, Lebanon, Malta, Morocco, Tunisia and Turkey. Overall, 26% (335) of isolates were reported as non-susceptible to penicillin, with the highest proportions being reported from Algeria (44%) and Lebanon (40%). During the same time period, the highest proportions of pneumococci that were not susceptible to erythromycin were reported from Malta (46%) and Tunisia (39%). Proportions of dual non-susceptibility in excess of 5% were found in laboratories in Algeria, Tunisia, Lebanon, Jordan and Turkey. ARMed data on the antimicrobial resistance epidemiology of S. pneumoniae in the southern and eastern Mediterranean region provided evidence of high rates of resistance, especially to penicillin. This evidence calls for a greater focus on the identification of relevant drivers of resistance and on the implemention of effective practices in order to address the problem of resistence.

Dynamics of Increasing IFN-γ Exposure on Murine MH-S Cell-Line Alveolar Macrophage Phagocytosis of Streptococcus pneumoniae

PubMed Central

Brown, Lou Ann S.; Klugman, Keith P.

2015-01-01

Previous investigations have demonstrated that activation with the type II interferon, IFN-γ, downregulates alveolar macrophage (AM) phagocytosis of Streptococcus pneumoniae. While these studies have shown clear effects at discrete time points, the kinetics of the macrophage response to IFN-γ over time, with respect to pneumococcal phagocytosis, have not been shown. Here, we describe these kinetics in the murine MH-S AM cell-line, a well-established model useful for investigations of AM phenotype and function. We measure binding and internalizing rates of S. pneumoniae following exposure to increasing durations of physiologic levels of IFN-γ. When MH-S murine alveolar macrophage (mAM) were exposed to IFN-γ for increasing durations of time, from 0 to 6 days before inoculation with the type II S. pneumoniae, D39, exposure for 6 h transiently reduced bacterial binding by 50%, which was temporarily restored at 2 and 3 days of exposure. Bacterial internalization was also reduced shortly following initial exposure, however, internalization continued to fall to less than 5% that of IFN-γ naïve controls after 6 days of exposure. These data may help explain otherwise contradictory reports from the literature regarding timing between infections and reductions in macrophage function. PMID:25713979

Dynamics of Increasing IFN-γ Exposure on Murine MH-S Cell-Line Alveolar Macrophage Phagocytosis of Streptococcus pneumoniae.

PubMed

Mina, Michael J; Brown, Lou Ann S; Klugman, Keith P

2015-06-01

Previous investigations have demonstrated that activation with the type II interferon, IFN-γ, downregulates alveolar macrophage (AM) phagocytosis of Streptococcus pneumoniae. While these studies have shown clear effects at discrete time points, the kinetics of the macrophage response to IFN-γ over time, with respect to pneumococcal phagocytosis, have not been shown. Here, we describe these kinetics in the murine MH-S AM cell-line, a well-established model useful for investigations of AM phenotype and function. We measure binding and internalizing rates of S. pneumoniae following exposure to increasing durations of physiologic levels of IFN-γ. When MH-S murine alveolar macrophage (mAM) were exposed to IFN-γ for increasing durations of time, from 0 to 6 days before inoculation with the type II S. pneumoniae, D39, exposure for 6 h transiently reduced bacterial binding by 50%, which was temporarily restored at 2 and 3 days of exposure. Bacterial internalization was also reduced shortly following initial exposure, however, internalization continued to fall to less than 5% that of IFN-γ naïve controls after 6 days of exposure. These data may help explain otherwise contradictory reports from the literature regarding timing between infections and reductions in macrophage function.

Isolation, identification, and antibacterial activity of chemical compounds from ethanolic extract of suji leaf (Pleomele angusifolia NE Brown)

NASA Astrophysics Data System (ADS)

Faridah; Natalia; Lina, Maria; W, Hendig

2014-03-01

Suji (Pleomele angustifolia NE Brown) is one of the medicinal plants of the tribe of Liliaceae, empirically useful to treat coughs and respiratory diseases such as tuberculosis (TB) and pneumonia. In this study, ethanolic extract of suji leaves was tested its activity against bacteria that attacks the respiratory organs, namely Mycobacterium tuberculosis and Streptococcus pneumoniae, using a paper disc diffusion and dilution agar method. These extracts have activity in inhibiting the growth of M. tuberculosis at a concentration of 8 mg and against S. pneumoniae at a concentration of 4 mg. The fractions were tested their antibacterial activity against Streptococcus pneumoniae using paper disc diffusion method. The most active fraction was chosen based on the inhibition diameter. The fractions contained flavonoids, steroids, and essential oils. The precipitate isolated from the extraction process shows needle-shaped, white, cold and tasteless crystals. Moreover, the HPLC analysis of isolate revealed a single peak with a retention time of 7.183 minutes. The exact compounds in the isolate could not be determined but it was known the compounds contained the functional groups of alkene, alkane, C=O, -OH. Test results obtained from UV-Vis spectrophotometer provides maximum absorption at a wavelength of 203.0 nm.

S-carboxymethylcysteine inhibits adherence of Streptococcus pneumoniae to human alveolar epithelial cells.

PubMed

Sumitomo, Tomoko; Nakata, Masanobu; Yamaguchi, Masaya; Terao, Yutaka; Kawabata, Shigetada

2012-01-01

Streptococcus pneumoniae is a major pathogen of respiratory infections that utilizes platelet-activating factor receptor (PAFR) for firm adherence to host cells. The mucolytic agent S-carboxymethylcysteine (S-CMC) has been shown to exert inhibitory effects against infection by several respiratory pathogens including S. pneumoniae in vitro and in vivo. Moreover, clinical studies have implicated the benefits of S-CMC in preventing exacerbation of chronic obstructive pulmonary disease, which is considered to be related to respiratory infections. In this study, to assess whether the potency of S-CMC is attributable to inhibition of pneumococcal adherence to host cells, an alveolar epithelial cell line stimulated with interleukin-1α was used as a model of inflamed epithelial cells. Despite upregulation of PAFR by inflammatory activation, treatment with S-CMC efficiently inhibited pneumococcal adherence to host epithelial cells. In order to gain insight into the inhibitory mechanism, the effects of S-CMC on PAFR expression were also investigated. Following treatment with S-CMC, PAFR expression was reduced at both mRNA and post-transcriptional levels. Interestingly, S-CMC was also effective in inhibiting pneumococcal adherence to cells transfected with PAFR small interfering RNAs. These results indicate S-CMC as a probable inhibitor targeting numerous epithelial receptors that interact with S. pneumoniae.

PD-1 suppresses protective immunity to Streptococcus pneumoniae through a B cell-intrinsic mechanism

PubMed Central

McKay, Jerome T.; Egan, Ryan P.; Yammani, Rama D.; Chen, Lieping; Shin, Tahiro; Yagita, Hideo; Haas, Karen M.

2015-01-01

Despite the emergence of the PD-1:PD-1 ligand (PD-L) regulatory axis as a promising target for treating multiple human diseases, remarkably little is known about how this pathway regulates responses to extracellular bacterial infections. We found that PD-1−/− mice, as well as wild type mice treated with a PD-1 blocking antibody, exhibited significantly increased survival against lethal Streptococcus pneumoniae infection following either priming with low-dose pneumococcal respiratory infection or S. pneumoniae-capsular polysaccharide immunization. Enhanced survival in mice with disrupted PD-1:PD-L interactions was explained by significantly increased proliferation, isotype switching, and IgG production by pneumococcal capsule-specific B cells. Both PD-1 ligands, B7-H1 and B7-DC, contributed to PD-1-mediated suppression of protective capsule-specific IgG. Importantly, PD-1 was induced on capsule-specific B cells and suppressed IgG production and protection against pneumococcal infection in a B cell-intrinsic manner. These results provide the first demonstration of a physiologic role for B cell-intrinsic PD-1 expression in vivo. In summary, our study reveals that B cell-expressed PD-1 plays a central role in regulating protection against S. pneumoniae, and thereby represents a promising target for bolstering immunity to encapsulated bacteria. PMID:25624454

Pyruvate oxidase of Streptococcus pneumoniae contributes to pneumolysin release.

PubMed

Bryant, Joseph C; Dabbs, Ridge C; Oswalt, Katie L; Brown, Lindsey R; Rosch, Jason W; Seo, Keun S; Donaldson, Janet R; McDaniel, Larry S; Thornton, Justin A

2016-11-09

Streptococcus pneumoniae is one of the leading causes of community acquired pneumonia and acute otitis media. Certain aspects of S. pneumoniae's virulence are dependent upon expression and release of the protein toxin pneumolysin (PLY) and upon the activity of the peroxide-producing enzyme, pyruvate oxidase (SpxB). We investigated the possible synergy of these two proteins and identified that release of PLY is enhanced by expression of SpxB prior to stationary phase growth. Mutants lacking the spxB gene were defective in PLY release and complementation of spxB restored PLY release. This was demonstrated by cytotoxic effects of sterile filtered supernatants upon epithelial cells and red blood cells. Additionally, peroxide production appeared to contribute to the mechanism of PLY release since a significant correlation was found between peroxide production and PLY release among a panel of clinical isolates. Exogenous addition of H 2 O 2 failed to induce PLY release and catalase supplementation prevented PLY release in some strains, indicating peroxide may exert its effect intracellularly or in a strain-dependent manner. SpxB expression did not trigger bacterial cell death or LytA-dependent autolysis, but did predispose cells to deoxycholate lysis. Here we demonstrate a novel link between spxB expression and PLY release. These findings link liberation of PLY toxin to oxygen availability and pneumococcal metabolism.

Synthesis and SARs of novel lincomycin derivatives Part 5: optimization of lincomycin analogs exhibiting potent antibacterial activities by chemical modification at the 6- and 7-positions.

PubMed

Wakiyama, Yoshinari; Kumura, Ko; Umemura, Eijiro; Masaki, Satomi; Ueda, Kazutaka; Sato, Yasuo; Hirai, Yoko; Hayashi, Yoshio; Ajito, Keiichi

2018-02-01

In order to modify lincomycin at the C-6 and C-7 positions, we prepared target molecules, which have substituted pipecolinic acid at the 6-amino group and a para-substituted phenylthio group at the C-7 position, in application of palladium-catalyzed cross-coupling as a key reaction. As the result of structure-activity relationship (SAR) studies at the 6-position, analogs possessing 4'-cis-(cyclopropylmethyl)piperidine showed significantly strong antibacterial activities against Streptococcus pneumoniae and Streptococcus pyogenes with an erm gene. On the basis of SAR, we further synthesized novel analogs possessing 4'-cis-(cyclopropylmethyl)piperidine by transformation of a C-7 substituent. Consequently, novel derivatives possessing a para-heteroaromatic-phenylthio group at the C-7 position exhibited significantly strong activities against S. pneumoniae and S. pyogenes with an erm gene even when compared with those of telithromycin. Finally, in vivo efficacy of selected two derivatives was evaluated in a rat pulmonary infection model with resistant S. pneumoniae with erm + mef genes. One of them exhibited strong and constant in vivo efficacy in this model, and both compounds showed strong in vivo efficacy against resistant S. pneumoniae with a mef gene.

Solution structure of the Big domain from Streptococcus pneumoniae reveals a novel Ca2+-binding module

PubMed Central

Wang, Tao; Zhang, Jiahai; Zhang, Xuecheng; Xu, Chao; Tu, Xiaoming

2013-01-01

Streptococcus pneumoniae is a pathogen causing acute respiratory infection, otitis media and some other severe diseases in human. In this study, the solution structure of a bacterial immunoglobulin-like (Big) domain from a putative S. pneumoniae surface protein SP0498 was determined by NMR spectroscopy. SP0498 Big domain adopts an eight-β-strand barrel-like fold, which is different in some aspects from the two-sheet sandwich-like fold of the canonical Ig-like domains. Intriguingly, we identified that the SP0498 Big domain was a Ca2+ binding domain. The structure of the Big domain is different from those of the well known Ca2+ binding domains, therefore revealing a novel Ca2+-binding module. Furthermore, we identified the critical residues responsible for the binding to Ca2+. We are the first to report the interactions between the Big domain and Ca2+ in terms of structure, suggesting an important role of the Big domain in many essential calcium-dependent cellular processes such as pathogenesis. PMID:23326635

Designed Reduction of Streptococcus pneumoniae Pathogenicity via Synthetic Changes in Virulence Factor Codon-pair Bias

PubMed Central

Coleman, J. Robert; Papamichail, Dimitris; Yano, Masahide; García-Suárez, María del Mar

2011-01-01

In this study, we used a previously described method of controlling gene expression with computer-based gene design and de novo DNA synthesis to attenuate the virulence of Streptococcus pneumoniae. We produced 2 S. pneumoniae serotype 3 (SP3) strains in which the pneumolysin gene (ply) was recoded with underrepresented codon pairs while retaining its amino acid sequence and determined their ply expression and pneumolysin production in vitro and their virulence in a mouse pulmonary infection model. Expression of ply and production of pneumolysin of the recoded SP3 strains were decreased, and the recoded SP3 strains were less virulent in mice than the wild-type SP3 strain or a Δply SP3 strain. Further studies showed that the least virulent recoded strain induced a markedly reduced inflammatory response in the lungs compared with the wild-type or Δply strain. These findings suggest that reducing pneumococcal virulence gene expression by altering codon-pair bias could hold promise for rational design of live-attenuated pneumococcal vaccines. PMID:21343143

Apigenin protects mice from pneumococcal pneumonia by inhibiting the cytolytic activity of pneumolysin.

PubMed

Song, Meng; Li, Li; Li, Meng; Cha, Yonghong; Deng, Xuming; Wang, Jianfeng

2016-12-01

Streptococcus pneumoniae is an important human pathogenic bacterium that can cause various life-threatening infections. Pneumolysin (PLY), the pore-forming toxin that forms large pores in the cell membrane, is a key virulence factor secreted by S. pneumoniae that penetrates the physical defenses of the host and plays an important role in the pathogenesis of pneumococcal diseases, such as pneumonia, meningitis, bacteremia and otitis media. This study showed that apigenin, one of the bioflavonoids widely found in herbs, inhibits PLY-induced hemolysis by inhibiting the oligomerization of PLY and has no anti-S. pneumoniae activity. In addition, when PLY was incubated with human alveolar epithelial (A549) cells, apigenin could effectively alleviate PLY-mediated cell injury. In vivo studies further demonstrated that apigenin could protect mice against S. pneumoniae pneumonia. These results imply that apigenin could directly interact with PLY to decrease the pathogenicity of S. pneumoniae and that novel therapeutics against S. pneumoniae PLY might provide greater effectiveness in combatting S. pneumoniae pneumonia. Copyright © 2016 Elsevier B.V. All rights reserved.

Mixed community-acquired pneumonia in hospitalised patients.

PubMed

de Roux, A; Ewig, S; García, E; Marcos, M A; Mensa, J; Lode, H; Torres, A

2006-04-01

The role of mixed community-acquired pneumonia (CAP) is controversial. The aim of the present study was to determine the incidence, principal microbial patterns, clinical predictors and course of mixed CAP. The current study included 1,511 consecutive hospitalised patients with CAP. Of these, 610 (40%) patients had an established aetiology. One pathogen was demonstrated in 528 patients and 82 (13%) patients had mixed pneumonia. Cases including CAP, by a pyogenic bacteria and a complete paired serology for "atypicals", revealed that 82 (13%) patients had definite single pyogenic pneumonia and 28 patients (5%) had mixed pyogenic pneumonia. In patients with mixed CAP, Streptococcus pneumoniae was the most prevalent microorganism (44 out of 82; 54%). The most frequent combination was S. pneumoniae with Haemophilus influenzae (17 out of 82; 21%). Influenza virus A and S. pneumoniae (five out of 28; 18%) was the most frequent association in the mixed pyogenic pneumonia group. No clinical predictors for mixed pneumonias could be identified. Patients with mixed pyogenic pneumonia more frequently developed shock when compared with patients with single pyogenic pneumonia (18 versus 4%). In conclusion, mixed pneumonia occurs in >10% of cases with community-acquired pneumonia requiring hospitalisation.

Community-acquired pneumonia in children.

PubMed

Stuckey-Schrock, Kimberly; Hayes, Burton L; George, Christa M

2012-10-01

Community-acquired pneumonia is a potentially serious infection in children and often results in hospitalization. The diagnosis can be based on the history and physical examination results in children with fever plus respiratory signs and symptoms. Chest radiography and rapid viral testing may be helpful when the diagnosis is unclear. The most likely etiology depends on the age of the child. Viral and Streptococcus pneumoniae infections are most common in preschool-aged children, whereas Mycoplasma pneumoniae is common in older children. The decision to treat with antibiotics is challenging, especially with the increasing prevalence of viral and bacterial coinfections. Preschool-aged children with uncomplicated bacterial pneumonia should be treated with amoxicillin. Macrolides are first-line agents in older children. Immunization with the 13-valent pneumococcal conjugate vaccine is important in reducing the severity of childhood pneumococcal infections.

Swine flu and antibiotics.

PubMed

Barlow, Gavin D

2009-11-01

Health services worldwide are likely to be hard-pressed by swine flu-related illness in the months ahead. Secondary infections with Streptococcus pneumoniae, other streptococci (e.g. Streptococcus pyogenes), Haemophilus influenzae and Staphylococcus aureus are likely to be important causes of morbidity and mortality. The UK Department of Health recently published clinical pathways for the management of swine flu. Suggested severity criteria have not been validated in respiratory infection and are different from those previously published. Antibiotics are recommended for all patients assessed at hospital, regardless of severity of illness; cephalosporins or quinolones are suggested for inpatients with pneumonia. These recommendations will jeopardize recent decreases in Clostridium difficile-associated diarrhoea (CDAD) and methicillin-resistant S. aureus (MRSA) in UK hospitals. This article, written on behalf of the BSAC Council, considers these recommendations and provides alternative antibiotic regimens for a range of clinical scenarios.

Photodynamic inactivation of microorganisms which cause pulmonary diseases with infrared light: an in vitro study

NASA Astrophysics Data System (ADS)

Leite, Ilaiáli S.; Geralde, Mariana C.; Salina, Ana C.; Medeiros, Alexandra I.; Kurachi, Cristina; Bagnato, Vanderlei S.; Inada, Natalia M.

2014-03-01

Lower respiratory infections are among the leading causes of death worldwide. In this study, it was evaluated the interaction of indocyanine green, a photosensitizer activated by infrared light, with alveolar macrophages and the effectiveness of the photodynamic therapy using this compound against Streptococcus pneumoniae . Initial experiments analyzed indocyanine green toxicity to alveolar macrophages in the dark with different drug concentrations and incubation times, and macrophage viability was obtained with the MTT method. The average of the results showed viability values below 90% for the two highest concentrations. Experiments with Streptococcus pneumoniae showed photodynamic inactivation with 10 μM indocyanine green solution. Further experiments with the bacteria in co-culture with AM will be conducted verifying the photodynamic inactivation effectiveness of the tested drug concentrations and incubation periods using infrared light.

Clonal Spread of Levofloxacin-Resistant Streptococcus pneumoniae Invasive Isolates in Madrid, Spain, 2007 to 2009▿

PubMed Central

Rodríguez-Avial, Iciar; Ramos, Belén; Ríos, Esther; Cercenado, Emilia; Ordobás, María; Sanz, Juan Carlos

2011-01-01

Among 1,349 Streptococcus pneumoniae invasive isolates, 45 (3.3%) were levofloxacin resistant. Serotype distribution was as follows: 8 (n = 32 isolates), 19A (n = 4 isolates), 7F (n = 3 isolates), 9V (n = 2 isolates), 10A (n = 1 isolate), 19F (n = 1 isolate), 6B (n = 1 isolate), and nontypeable (n = 1 isolate). Levofloxacin-resistant isolates had dual mutations in the gyrA and parC genes. Serotype 8 strains corresponded to a capsular switching of the Sweden15A-25 clone. Levofloxacin resistance was also detected among multiresistant (ST27619A, Spain9V-ST156, ST8819F, and ST15426B) and among usually antibiotic-susceptible (Netherlands7F-ST191, ST120119A, and ST263910A) clones. PMID:21383091

Functional role of R462 in the degradation of hyaluronan catalyzed by hyaluronate lyase from Streptococcus pneumoniae.

PubMed

Li, Fengxue; Xu, Dingguo

2015-08-01

Hyaluronan lyase from Streptococcus pneumoniae can degrade hyaluronic acid, which is one of the major components in the extracellular matrix. Hyaluronan can regulate water balance, osmotic pressure, and act as an ion exchange resin. Followed by our recent work on the catalytic reaction mechanism and substrate binding mode, we in this work further investigate the functional role of active site arginine residue, R462, in the degradation of hyaluronan. The site directed mutagenesis simulation of R462A and R462Q were modeled using a combined quantum mechanical and molecular mechanical method. The overall substrate binding features upon mutations do not have significant changes. The energetic profiles for the reaction processes are essentially the same as that in wild type enzyme, but significant activation barrier height changes can be observed. Both mutants were shown to accelerate the overall enzymatic activity, e.g., R462A can reduce the barrier height by about 2.8 kcal mol(-1), while R462Q reduces the activation energy by about 2.9 kcal mol(-1). Consistent with the active site model calculated using density functional theory, our results can support that the positive charge on R462 guanidino side chain group plays a negative role in the catalysis. Finally, the functional role of R462 was proposed to facilitate the formation of initial enzyme-substrate complex, but not in the subsequent catalytic degradation reaction. Graphical Abstract Degradation of hyaluronan catalyzed by hyaluronate lyase from Streptococcus pneumoniae.

[Distribution and drug resistance of the pathogenic bacteria from sputum specimens of 1 125 children with tracheo bronchial foreign bodies].

PubMed

Wen, Xin; Su, Jinzhu; Cui, Li; Wang, Juan; Zuo, Lujie

2015-02-01

To analyze the distribution and drug susceptibility of the pathogenic bacteria in the airway secretions in children with tracheobronchial foreign bodies so as to assist physicians in clinical prescription. Sputum specimens of 1 125 children with tracheobronchial foreign bodies were collected in removal of the foreign bodies by rigid bronchoscope, and the drug susceptibility test was performed. Pathogenic bacteria were detected in 218 (19.4%) of 1 125 sputum specimens. Among the pathogenic bacteria, 126 (57.79%) strains were gram-negative bacilli, consisting of 76 (34.86%) strains of Haemophilus influenzae, 10 (4.59%) strains of Escherichia coli, 7 (3.21%) strains of Sewer enterobacter, 7 (3.21%) strains of Pseudomonas aeruginosa, and 6 (2.75%) strains of Klebsiella bacillus; and 92 (42.21%) strains were gram-positive bacilli, consisting of 80 (36.69%) strains of Streptococcus pneumonia and 10 (4.59%) strains of Escherichia coli. Most of detected gram-negative bacilli were highly sensitive to cefepime, ceftazidine, imipenem and amikacin, no strains were resistant to meropenem and ciprofloxacin. None of the detected gram-positive bacilli were resistant to cefepime, vancomycin, levofloxacin and teicoplanin. The Haemophilus influenzae of gram-negative bacilli and the Streptococcus pneumonia of gram-positive bacilli are the main pathogenic bacteria existing in the airway secretions of children with tracheobronchial foreign bodies. The Haemophilus influenzae were highly sensitive to cephalosporin, imipenem and amikacin, and the Streptococcus pneumonia to cefepime, vancomycin, levofloxacin and teicoplanin.

SUSCEPTIBILITY OF RESPIRATORY ISOLATES OF STREPTOCOCCUS PNEUMONIAE ISOLATED FROM CHILDREN HOSPITALIZED IN THE CLINICAL CENTER NIS.

PubMed

Dinić, Marina M; Mladenović Antić, Snezana; Kocić, Branislava; Stanković Dordević, Dobrila; Vrbić, Miodrag; Bogdanović, Milena

2016-01-01

Streptococcus pneumoniae is one of the most common causes of respiratory infections. The aim was to study the susceptibility to antimicrobial agents of respiratory isolates ofStreptococcus pneumoniae obtained from hospitalized children. A total of 190 respiratory pneumococcal isolates obtained from children aged from 0 to 14 years were isolated and identified by using standard microbiological methods. Susceptibility to oxacillin, erythromycin, clindamycin, tetracycline, cotrimoxazole, ofloxacin and rifampicin was tested by disc diffusion method. Minimal inhibitory concentrations for amoxicillin and ceftriaxone were determined by means of E test. The macrolide-resistant phenotype was detected by double disc diffusion test. All tested isolates were susceptible to amoxicillin and ceftriaxone. The minimal amoxicillin concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.50 microg/ml and 1.0 microg/ml, respectively and the minimal ceftriaxone concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.25 microg/ml and 0.50 microg/ml, respectively. Susceptibility to erythromycin and clindamycin was observed in 21.6% and 29.47% of isolates, respectively. The resistence to macrolides-M phenotype was detected in 10.07% of isolates and constitutive macrolide-lincosamide-streptogramin phenotype (constitutive MLS phenotype) was found in 89.93% of isolates. All tested isolates were susceptible to ofloxacin and rifampicin. Amoxicillin could be the therapy of choice in pediatric practice. The macrolides should not be recommended for the empirical therapy of pneumococcal respiratory tract infection in our local area.

Identification of a functional capsule locus in Streptococcus mitis.

PubMed

Rukke, H V; Hegna, I K; Petersen, F C

2012-04-01

The polysaccharide capsule of Streptococcus pneumoniae is a hallmark for virulence in humans. In its close relative Streptococcus mitis, a common human commensal, analysis of the sequenced genomes of six strains revealed the presence of a putative capsule locus in four of them. We constructed an isogenic S. mitis mutant from the type strain that lacked the 19 open reading frames in the capsule locus (Δcps mutant), using a deletion strategy similar to previous capsule functional studies in S. pneumoniae. Transmission electron microscopy and atomic force microscopy revealed a capsule-like structure in the S. mitis type strain that was absent or reduced in the Δcps mutant. Since S. mitis are predominant oral colonizers of tooth surfaces, we addressed the relevance of the capsule locus for the S. mitis overall surface properties, autoaggregation and biofilm formation. The capsule deletion resulted in a mutant with approximately two-fold increase in hydrophobicity. Binding to the Stains-all cationic dye was reduced by 40%, suggesting a reduction in the overall negative surface charge of the mutant. The mutant exhibited also increased autoaggregation in coaggregation buffer, and up to six-fold increase in biofilm levels. The results suggested that the capsule locus is associated with production of a capsule-like structure in S. mitis and indicated that the S. mitis capsule-like structure may confer surface attributes similar to those associated with the capsule in S. pneumoniae. © 2011 John Wiley & Sons A/S.

Combining Use of Captopril and Losartan Attenuates the Progress of Streptococcus pneumoniae-Induced Tympanosclerosis through the Suppression of TGF-β1 Expression

PubMed Central

Yan, Wenqing; Li, Jianfeng; Chai, Renjie; Guo, Wentao; Xu, Lei; Han, Yuechen; Bai, Xiaohui; Wang, Haibo

2014-01-01

Objectives In this study, using an Streptococcus pneumoniae-induced tympanosclerosis (TS) model, we explored the effects of captopril and losartan in the treatment of TS and the possible mechanisms. Study Design A prospective experimental animal study. Methods We set up the TS models in both guinea pig and wistar rat by inoculation of type-3 Streptococcus pneumoniae microorganisms and then treated the animals with the combining use of captopril and losartan. Otomicroscopy was employed to observe the development of TS. Auditory brainstem response was used to test the hearing function of animals. Hematoxylin-eosin and von Kossa staining were performed to determine the morphological changes and calcium depositions. The protein expressions of transforming growth factor β1 (TGF-β1) were assessed by western blot and immunohistochemistry staining, and the mRNA level of TGF-β1 was measured by quantitative reverse transcription- polymerase chain reaction. Results The combining use of captopril and losartan attenuated TS responses in terms of a decrease in the TS incidence and the ABR threshold, a reduction of hyalinization and calcification in the middle ear mucosa and the thickness of the mucosa. In addition, the TGF-β1 expression was decreased at both protein and mRNA levels. Conclusion Our data indicate, for the first time, that the combining use of captopril and losartan obviously attenuates TS progress through inhibiting the overexpressing of TGF-β1. PMID:25360706

[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.

Evolving trends of neonatal and childhood bacterial meningitis in northern Taiwan.

PubMed

Lin, Meng-Chin; Chiu, Nan-Chang; Chi, Hsin; Ho, Che-Sheng; Huang, Fu-Yuan

2015-06-01

The epidemiology of bacterial meningitis varies in different areas, age groups, and times. To know the trend of neonatal and childhood bacterial meningitis in northern Taiwan, we performed this 29-year-long assessment. Eligible patients were aged 18 years or younger, hospitalized in Mackay Memorial Hospital between 1984 and 2012, and proven by positive cerebrospinal fluid bacterial cultures. Analysis included the patient numbers and pathogens in different age groups, periods, complications, and outcomes. Males were predominant in all the age groups through the years. Almost half of the patients were in the neonatal period. Patient numbers went up in the early study period and declined after 1993-1997. Group B Streptococcus and Escherichia coli were the most common pathogens in neonates, whereas in childhood were Streptococcus pneumoniae and Haemophilus influenzae type b (Hib). Patient numbers of Group B Streptococcus, S. pneumoniae, and Hib meningitis declined in the late study period, but E. coli meningitis increased. The mortality rate decreased but sequela rate increased. Among the four most common pathogens, S. pneumoniae had the worst outcome and had highest mortality rate. All Hib meningitis patients survived, but their sequela rate was the highest. This study provides an epidemiological data on trends of neonatal and childhood bacterial meningitis in northern Taiwan during the past 29 years, including male and neonatal predominance, decrease of total patient number in recent years, change of major pathogens, and declined mortality but raised morbidity. Copyright © 2013. Published by Elsevier B.V.

A Thioesterase Bypasses the Requirement for Exogenous Fatty Acids in the plsX Deletion of Streptococcus pneumoniae

PubMed Central

Parsons, Joshua B.; Frank, Matthew W.; Eleveld, Marc J.; Schalkwijk, Joost; Broussard, Tyler C.; de Jonge, Marien I.; Rock, Charles O.

2015-01-01

Summary PlsX is an acyl-acyl carrier protein (ACP):phosphate transacylase that interconverts the two acyl donors in Gram-positive bacterial phospholipid synthesis. The deletion of plsX in Staphylococcus aureus results in a requirement for both exogenous fatty acids and de novo type II fatty acid biosynthesis. Deletion of plsX (SP0037) in Streptococcus pneumoniae did not result in an auxotrophic phenotype. The ΔplsX S. pneumoniae strain was refractory to myristic acid-dependent growth arrest, and unlike the wild-type strain, was susceptible to fatty acid synthesis inhibitors in the presence of exogenous oleate. The ΔplsX strain contained longer-chain saturated fatty acids imparting a distinctly altered phospholipid molecular species profile. An elevated pool of 18- and 20-carbon saturated fatty acids was detected in the ΔplsX strain. A S. pneumoniae thioesterase (TesS, SP1408) hydrolyzed acyl-ACP in vitro, and the ΔtesS ΔplsX double knockout strain was a fatty acid auxotroph. Thus, the TesS thioesterase hydrolyzed the accumulating acyl-ACP in the ΔplsX strain to liberate fatty acids that were activated by fatty acid kinase to bypass a requirement for extracellular fatty acid. This work identifies tesS as the gene responsible for the difference in exogenous fatty acid growth requirement of the ΔplsX strains of S. aureus and S. pneumoniae. PMID:25534847

Immunoglobulin deficiency in patients with Streptococcus pneumoniae or Haemophilus influenzae invasive infections.

PubMed

Martinot, Martin; Oswald, Laetitia; Parisi, Elisabeth; Etienne, Elodie; Argy, Nicolas; Grawey, Isabelle; De Briel, Dominique; Zadeh, Mahsa Mohseni; Federici, Laure; Blaison, Gilles; Koebel, Christelle; Jaulhac, Benoit; Hansmann, Yves; Christmann, Daniel

2014-02-01

Immunoglobulin (Ig) deficiency is a well-known risk factor for Streptococcus pneumoniae or Haemophilus influenzae infections and noteworthy invasive diseases. However, the proportion of these deficiencies in cases of invasive disease is unknown. The objective of this study was to evaluate the rate of Ig deficiency in cases of invasive disease. A prospective study was conducted from January 2008 to October 2010 in two French hospitals. Measurement of Ig levels was carried out in patients hospitalized for invasive diseases. A total of 119 patients were enrolled in the study, with nine cases of H. influenzae and 110 cases of S. pneumoniae invasive disease. There were 18 cases of meningitis, 79 of invasive pneumonia, and 22 other invasive diseases. Forty-five patients (37.8%) had an Ig abnormality, 37 of whom had an Ig deficiency (20 IgG <6g/l, four isolated IgA <0.7g/l, and 13 isolated IgM <0.5g/l), while eight had an elevated monoclonal paraprotein. Nineteen of these 45 patients had a clearly defined Ig abnormality, with five primary deficiencies (three common variable immunodeficiencies and two complete IgA deficiencies) and 14 secondary deficiencies, mainly lymphoproliferative disorders. All these deficiencies were either not known or not substituted. Humoral deficiency is frequent in patients with S. pneumoniae or H. influenzae invasive disease and Ig dosage should be proposed systematically after such infections. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Red Fluorescent Proteins for Gene Expression and Protein Localization Studies in Streptococcus pneumoniae and Efficient Transformation with DNA Assembled via the Gibson Assembly Method.

PubMed

Beilharz, Katrin; van Raaphorst, Renske; Kjos, Morten; Veening, Jan-Willem

2015-10-01

During the last decades, a wide range of fluorescent proteins (FPs) have been developed and improved. This has had a great impact on the possibilities in biological imaging and the investigation of cellular processes at the single-cell level. Recently, we have benchmarked a set of green fluorescent proteins (GFPs) and generated a codon-optimized superfolder GFP for efficient use in the important human pathogen Streptococcus pneumoniae and other low-GC Gram-positive bacteria. In the present work, we constructed and compared four red fluorescent proteins (RFPs) in S. pneumoniae. Two orange-red variants, mOrange2 and TagRFP, and two far-red FPs, mKate2 and mCherry, were codon optimized and examined by fluorescence microscopy and plate reader assays. Notably, protein fusions of the RFPs to FtsZ were constructed by direct transformation of linear Gibson assembly (isothermal assembly) products, a method that speeds up the strain construction process significantly. Our data show that mCherry is the fastest-maturing RFP in S. pneumoniae and is best suited for studying gene expression, while mKate2 and TagRFP are more stable and are the preferred choices for protein localization studies. The RFPs described here will be useful for cell biology studies that require multicolor labeling in S. pneumoniae and related organisms. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Pneumolysin with Low Hemolytic Activity Confers an Early Growth Advantage to Streptococcus pneumoniae in the Blood ▿

PubMed Central

Harvey, Richard M.; Ogunniyi, Abiodun D.; Chen, Austen Y.; Paton, James C.

2011-01-01

Streptococcus pneumoniae is a leading cause of human diseases such as pneumonia, bacteremia, meningitis, and otitis media. Pneumolysin (Ply) is an important virulence factor of S. pneumoniae and a promising future vaccine target. However, the expansion of clones carrying ply alleles with reduced hemolytic activity has been observed in serotypes associated with outbreaks of invasive disease and includes an allele identified in a highly virulent serotype 1 isolate (ply4496). The virulence of Ply-deficient and ply allelic-replacement derivatives of S. pneumoniae D39 was compared with that of wild-type D39. In addition, the protective immunogenicity of Ply against pneumococci with low versus high hemolytic activity was also investigated. Replacement of D39 ply with ply4496 resulted in a small but statistically significant reduction of virulence. However, both native Ply- and Ply4496-expressing strains were significantly more virulent than a Ply-deficient mutant. While the numbers of both Ply- and Ply4496-expressing isolate cells were higher in the blood than the numbers of Ply-deficient mutant cells, the growth of the Ply4496-expressing strain was superior to that of the wild type in the first 15 h postchallenge. Ply immunization provided protection regardless of the hemolytic activity of the challenge strain. In summary, we show that low-hemolytic-activity Ply alleles contribute to systemic virulence and may provide a survival advantage in the blood. Moreover, pneumococci expressing such alleles remain vulnerable to Ply-based vaccines. PMID:21788389

Human antibodies to PhtD, PcpA, and Ply reduce adherence to human lung epithelial cells and murine nasopharyngeal colonization by Streptococcus pneumoniae.

PubMed

Kaur, Ravinder; Surendran, Naveen; Ochs, Martina; Pichichero, Michael E

2014-12-01

Streptococcus pneumoniae adherence to human epithelial cells (HECs) is the first step in pathogenesis leading to infections. We sought to determine the role of human antibodies against S. pneumoniae protein vaccine candidates PhtD, PcpA, and Ply in preventing adherence to lung HECs in vitro and mouse nasopharyngeal (NP) colonization in vivo. Human anti-PhtD, -PcpA, and -Ply antibodies were purified and Fab fragments generated. Fabs were used to test inhibition of adherence of TIGR4 and nonencapsulated strain RX1 to A549 lung HECs. The roles of individual proteins in adherence were tested using isogenic mutants of strain TIGR4. Anti-PhtD, -PcpA, and -Ply human antibodies were assessed for their ability to inhibit NP colonization in vivo by passive transfer of human antibody in a murine model. Human antibodies generated against PhtD and PcpA caused a decrease in adherence to A549 cells (P < 0.05). Anti-PhtD but not anti-PcpA antibodies showed a protective role against mouse NP colonization. To our surprise, anti-Ply antibodies also caused a significant (P < 0.05) reduction in S. pneumoniae colonization. Our results support the potential of PhtD, PcpA, and Ply protein vaccine candidates as alternatives to conjugate vaccines to prevent non-serotype-specific S. pneumoniae colonization and invasive infection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Pneumolysin with low hemolytic activity confers an early growth advantage to Streptococcus pneumoniae in the blood.

PubMed

Harvey, Richard M; Ogunniyi, Abiodun D; Chen, Austen Y; Paton, James C

2011-10-01

Streptococcus pneumoniae is a leading cause of human diseases such as pneumonia, bacteremia, meningitis, and otitis media. Pneumolysin (Ply) is an important virulence factor of S. pneumoniae and a promising future vaccine target. However, the expansion of clones carrying ply alleles with reduced hemolytic activity has been observed in serotypes associated with outbreaks of invasive disease and includes an allele identified in a highly virulent serotype 1 isolate (ply4496). The virulence of Ply-deficient and ply allelic-replacement derivatives of S. pneumoniae D39 was compared with that of wild-type D39. In addition, the protective immunogenicity of Ply against pneumococci with low versus high hemolytic activity was also investigated. Replacement of D39 ply with ply4496 resulted in a small but statistically significant reduction of virulence. However, both native Ply- and Ply4496-expressing strains were significantly more virulent than a Ply-deficient mutant. While the numbers of both Ply- and Ply4496-expressing isolate cells were higher in the blood than the numbers of Ply-deficient mutant cells, the growth of the Ply4496-expressing strain was superior to that of the wild type in the first 15 h postchallenge. Ply immunization provided protection regardless of the hemolytic activity of the challenge strain. In summary, we show that low-hemolytic-activity Ply alleles contribute to systemic virulence and may provide a survival advantage in the blood. Moreover, pneumococci expressing such alleles remain vulnerable to Ply-based vaccines.

Development of two real-time multiplex PCR assays for the detection and quantification of eight key bacterial pathogens in lower respiratory tract infections

PubMed Central

Gadsby, N.J.; McHugh, M.P.; Russell, C.D.; Mark, H.; Conway Morris, A.; Laurenson, I.F.; Hill, A.T.; Templeton, K.E.

2015-01-01

The frequent lack of a positive and timely microbiological diagnosis in patients with lower respiratory tract infection (LRTI) is an important obstacle to antimicrobial stewardship. Patients are typically prescribed broad-spectrum empirical antibiotics while microbiology results are awaited, but, because these are often slow, negative, or inconclusive, de-escalation to narrow-spectrum agents rarely occurs in clinical practice. The aim of this study was to develop and evaluate two multiplex real-time PCR assays for the sensitive detection and accurate quantification of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. We found that all eight bacterial targets could be reliably quantified from sputum specimens down to a concentration of 100 CFUs/reaction (8333 CFUs/mL). Furthermore, all 249 positive control isolates were correctly detected with our assay, demonstrating effectiveness on both reference strains and local clinical isolates. The specificity was 98% on a panel of nearly 100 negative control isolates. Bacterial load was quantified accurately when three bacterial targets were present in mixtures of varying concentrations, mimicking likely clinical scenarios in LRTI. Concordance with culture was 100% for culture-positive sputum specimens, and 90% for bronchoalveolar lavage fluid specimens, and additional culture-negative bacterial infections were detected and quantified. In conclusion, a quantitative molecular test for eight key bacterial causes of LRTI has the potential to provide a more sensitive decision-making tool, closer to the time-point of patient admission than current standard methods. This should facilitate de-escalation from broad-spectrum to narrow-spectrum antibiotics, substantially improving patient management and supporting efforts to curtail inappropriate antibiotic use. PMID:25980353

[Biological activity tests of chemical constituents from two Brazilian Labiatae plants].

PubMed

Isobe, Takahiko; Doe, Matsumi; Morimoto, Yoshiki; Nagata, Kumiko; Masuoka, Noriyoshi; Ohsaki, Ayumi

2007-02-01

We studied the bioactivities of constituents from two tropical medicinal plants, Cunila spicata and Hyptis fasciculata. These plants found in Brazil belong to the Labiatae family. Four known compounds obtained from these herbs were identified as 3alpha, 24-dihydoxylurs-12-en-28-oic acid, betulinic acid, aurantiamide acetate, and aurantiamide benzoate by spectroscopic means. 3alpha, 24-Dihydoxylurs-12-en-28-oic acid has potent inhibitory activity against Streptococcus salivarius, Streptococcus pneumoniae, Streptococcus pyogenes, and Porphyromomas gingivalis. Aurantiamide benzoate exhibited moderate inhibitory activity against xanthine oxidase. It was clarified that herbs Cunila spicata and Hyptis fasciculata are effective against bronchitis and gout.

In vitro activity of flomoxef in comparison to other cephalosporins.

PubMed

Simon, C; Simon, M; Plieth, C

1988-01-01

Flomoxef and cefazolin had nearly the same activity against staphylococci, which was stronger than that of other cephalosporins. Against Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus pneumoniae, cefotaxime and cefazolin were more active than flomoxef, but the other cephamycins were less active than flomoxef. In comparison to the other cephalosporins, latamoxef and flomoxef had higher activity against Branhamella catarrhalis, whereas cefotaxime, latamoxef and cefotetan were more active against Haemophilus influenzae. Flomoxef was the only drug exhibiting activity against Clostridium difficile. The activity of flomoxef and latamoxef against Bacteroides fragilis was stronger than that of the other cephalosporins, but Bacteroides bivius was resistant to each of these antibiotics.

Multiplex quantitative PCR for detection of lower respiratory tract infection and meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis

PubMed Central

2010-01-01

Background Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR) for detection of S. pneumoniae (9802 gene fragment), H. influenzae (omp P6 gene) and N. meningitidis (ctrA gene). The method was evaluated on bronchoalveolar lavage (BAL) samples from 156 adults with lower respiratory tract infection (LRTI) and 31 controls, and on 87 cerebrospinal fluid (CSF) samples from meningitis patients. Results The analytical sensitivity was not affected by using a combined mixture of reagents and a combined DNA standard (S. pneumoniae/H. influenzae/N. meningitidis) in single tubes. By blood- and BAL-culture and S. pneumoniae urinary antigen test, S. pneumoniae and H. influenzae were aetiological agents in 21 and 31 of the LTRI patients, respectively. These pathogens were identified by qmPCR in 52 and 72 of the cases, respectively, yielding sensitivities and specificities of 95% and 75% for S. pneumoniae, and 90% and 65% for H. influenzae, respectively. When using a cut-off of 105 genome copies/mL for clinical positivity the sensitivities and specificities were 90% and 80% for S. pneumoniae, and 81% and 85% for H. influenzae, respectively. Of 44 culture negative but qmPCR positive for H. influenzae, 41 were confirmed by fucK PCR as H. influenzae. Of the 103 patients who had taken antibiotics prior to sampling, S. pneumoniae and H. influenzae were identified by culture in 6% and 20% of the cases, respectively, and by the qmPCR in 36% and 53% of the cases, respectively. In 87 CSF samples S. pneumoniae and N. meningitidis were identified by culture and/or 16 S rRNA in 14 and 10 samples and by qmPCR in 14 and 10 samples, respectively, giving a sensitivity of 100% and a specificity of 100% for both bacteria. Conclusions The PCR provides increased sensitivity and the multiplex format facilitates diagnosis of S. pneumoniae, H. influenzae and N. meningitidis and the assay enable detection after antibiotic treatment has been installed. Quantification increases the specificity of the etiology for pneumonia. PMID:21129171

Multiplex quantitative PCR for detection of lower respiratory tract infection and meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis.

PubMed

Abdeldaim, Guma M K; Strålin, Kristoffer; Korsgaard, Jens; Blomberg, Jonas; Welinder-Olsson, Christina; Herrmann, Björn

2010-12-03

Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR) for detection of S. pneumoniae (9802 gene fragment), H. influenzae (omp P6 gene) and N. meningitidis (ctrA gene). The method was evaluated on bronchoalveolar lavage (BAL) samples from 156 adults with lower respiratory tract infection (LRTI) and 31 controls, and on 87 cerebrospinal fluid (CSF) samples from meningitis patients. The analytical sensitivity was not affected by using a combined mixture of reagents and a combined DNA standard (S. pneumoniae/H. influenzae/N. meningitidis) in single tubes. By blood- and BAL-culture and S. pneumoniae urinary antigen test, S. pneumoniae and H. influenzae were aetiological agents in 21 and 31 of the LTRI patients, respectively. These pathogens were identified by qmPCR in 52 and 72 of the cases, respectively, yielding sensitivities and specificities of 95% and 75% for S. pneumoniae, and 90% and 65% for H. influenzae, respectively. When using a cut-off of 10⁵ genome copies/mL for clinical positivity the sensitivities and specificities were 90% and 80% for S. pneumoniae, and 81% and 85% for H. influenzae, respectively. Of 44 culture negative but qmPCR positive for H. influenzae, 41 were confirmed by fucK PCR as H. influenzae. Of the 103 patients who had taken antibiotics prior to sampling, S. pneumoniae and H. influenzae were identified by culture in 6% and 20% of the cases, respectively, and by the qmPCR in 36% and 53% of the cases, respectively.In 87 CSF samples S. pneumoniae and N. meningitidis were identified by culture and/or 16 S rRNA in 14 and 10 samples and by qmPCR in 14 and 10 samples, respectively, giving a sensitivity of 100% and a specificity of 100% for both bacteria. The PCR provides increased sensitivity and the multiplex format facilitates diagnosis of S. pneumoniae, H. influenzae and N. meningitidis and the assay enable detection after antibiotic treatment has been installed. Quantification increases the specificity of the etiology for pneumonia.

Community-acquired pneumonia in chronic obstructive pulmonary disease: a Spanish multicenter study.

PubMed

Torres, A; Dorca, J; Zalacaín, R; Bello, S; El-Ebiary, M; Molinos, L; Arévalo, M; Blanquer, J; Celis, R; Iriberri, M; Prats, E; Fernández, R; Irigaray, R; Serra, J

1996-11-01

Community-acquired pneumonia (CAP) is an infectious illness that frequently motivates hospital admission when comorbid conditions are present. However, the epidemiology of CAP in relation to the underlying disease of the patients is not well known. We performed a prospective multicenter study with the aim of assessing the clinical characteristics, etiology, and outcome of chronic obstructive pulmonary disease (COPD) patients with CAP. Between October 1992 and December 1994 we studied 124 COPD patients (mean FEV1 40 +/- 11% of predicted, mean FVC/FEV1 49 +/- 10) admitted because of CAP to one of the participating centers. An attempt to obtain an etiologic diagnosis was performed by means of blood cultures (n = 123), sputum cultures (n = 97), pleural fluid cultures (n = 17), protected specimen brush samples (n = 41), percutaneous transthoracic needle aspiration (n = 41), and serology (n = 106). Etiologic diagnosis was achieved in 80 (64%) of cases, however, diagnosis based upon valid techniques was only possible in 73 (59%) cases. The main causal microorganisms were the following: Streptococcus pneumoniae in 32 (43%), Chlamydia pneumoniae in 9 (12%), Hemophilus influenzae in 7 (9%), Legionella pneumophila in 7 (9%), Streptococcus viridans in 3 (4%), Coxiella burnetii in 3 (4%), Mycoplasma pneumoniae in 2 (3%), Nocordia asteroides 2, Aspergillus ssp. 1, and others 10. In three of these cases the etiology was polymicrobial. Bacteremia was present in 19 (15%) cases; S. pneumoniae was the most frequent isolate (13 cases). Antibiotic treatment was modified in 22 cases due to etiologic findings, and in 9 due to therapeutic failure. Ten patients died (8%), and 22 needed mechanical ventilation, the mortality rate in the latter population being 23%. Total or partial resistance of S. pneumoniae to penicillin was observed in 10 of 32 (31%) isolations, and to erythromycin in 2 (6%). The results of this study are important for the standardization of empiric antibiotic strategies in COPD patients with pneumonia.

Highly Variable Streptococcus oralis Strains Are Common among Viridans Streptococci Isolated from Primates.

PubMed

Denapaite, Dalia; Rieger, Martin; Köndgen, Sophie; Brückner, Reinhold; Ochigava, Irma; Kappeler, Peter; Mätz-Rensing, Kerstin; Leendertz, Fabian; Hakenbeck, Regine

2016-01-01

Viridans streptococci were obtained from primates (great apes, rhesus monkeys, and ring-tailed lemurs) held in captivity, as well as from free-living animals (chimpanzees and lemurs) for whom contact with humans is highly restricted. Isolates represented a variety of viridans streptococci, including unknown species. Streptococcus oralis was frequently isolated from samples from great apes. Genotypic methods revealed that most of the strains clustered on separate lineages outside the main cluster of human S. oralis strains. This suggests that S. oralis is part of the commensal flora in higher primates and evolved prior to humans. Many genes described as virulence factors in Streptococcus pneumoniae were present also in other viridans streptococcal genomes. Unlike in S. pneumoniae, clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) gene clusters were common among viridans streptococci, and many S. oralis strains were type PI-2 (pilus islet 2) variants. S. oralis displayed a remarkable diversity of genes involved in the biosynthesis of peptidoglycan (penicillin-binding proteins and MurMN) and choline-containing teichoic acid. The small noncoding cia-dependent small RNAs (csRNAs) controlled by the response regulator CiaR might contribute to the genomic diversity, since we observed novel genomic islands between duplicated csRNAs, variably present in some isolates. All S. oralis genomes contained a β-N-acetyl-hexosaminidase gene absent in S. pneumoniae, which in contrast frequently harbors the neuraminidases NanB/C, which are absent in S. oralis. The identification of S. oralis-specific genes will help us to understand their adaptation to diverse habitats. IMPORTANCE Streptococcus pneumoniae is a rare example of a human-pathogenic bacterium among viridans streptococci, which consist of commensal symbionts, such as the close relatives Streptococcus mitis and S. oralis. We have shown that S. oralis can frequently be isolated from primates and a variety of other viridans streptococci as well. Genes and genomic islands which are known pneumococcal virulence factors are present in S. oralis and S. mitis, documenting the widespread occurrence of these compounds, which encode surface and secreted proteins. The frequent occurrence of CRISP-Cas gene clusters and a surprising variation of a set of small noncoding RNAs are factors to be considered in future research to further our understanding of mechanisms involved in the genomic diversity driven by horizontal gene transfer among viridans streptococci.

Highly Variable Streptococcus oralis Strains Are Common among Viridans Streptococci Isolated from Primates

PubMed Central

Denapaite, Dalia; Rieger, Martin; Köndgen, Sophie; Brückner, Reinhold; Ochigava, Irma; Kappeler, Peter; Mätz-Rensing, Kerstin; Leendertz, Fabian

2016-01-01

ABSTRACT Viridans streptococci were obtained from primates (great apes, rhesus monkeys, and ring-tailed lemurs) held in captivity, as well as from free-living animals (chimpanzees and lemurs) for whom contact with humans is highly restricted. Isolates represented a variety of viridans streptococci, including unknown species. Streptococcus oralis was frequently isolated from samples from great apes. Genotypic methods revealed that most of the strains clustered on separate lineages outside the main cluster of human S. oralis strains. This suggests that S. oralis is part of the commensal flora in higher primates and evolved prior to humans. Many genes described as virulence factors in Streptococcus pneumoniae were present also in other viridans streptococcal genomes. Unlike in S. pneumoniae, clustered regularly interspaced short palindromic repeat (CRISPR)–CRISPR-associated protein (Cas) gene clusters were common among viridans streptococci, and many S. oralis strains were type PI-2 (pilus islet 2) variants. S. oralis displayed a remarkable diversity of genes involved in the biosynthesis of peptidoglycan (penicillin-binding proteins and MurMN) and choline-containing teichoic acid. The small noncoding cia-dependent small RNAs (csRNAs) controlled by the response regulator CiaR might contribute to the genomic diversity, since we observed novel genomic islands between duplicated csRNAs, variably present in some isolates. All S. oralis genomes contained a β-N-acetyl-hexosaminidase gene absent in S. pneumoniae, which in contrast frequently harbors the neuraminidases NanB/C, which are absent in S. oralis. The identification of S. oralis-specific genes will help us to understand their adaptation to diverse habitats. IMPORTANCE Streptococcus pneumoniae is a rare example of a human-pathogenic bacterium among viridans streptococci, which consist of commensal symbionts, such as the close relatives Streptococcus mitis and S. oralis. We have shown that S. oralis can frequently be isolated from primates and a variety of other viridans streptococci as well. Genes and genomic islands which are known pneumococcal virulence factors are present in S. oralis and S. mitis, documenting the widespread occurrence of these compounds, which encode surface and secreted proteins. The frequent occurrence of CRISP-Cas gene clusters and a surprising variation of a set of small noncoding RNAs are factors to be considered in future research to further our understanding of mechanisms involved in the genomic diversity driven by horizontal gene transfer among viridans streptococci. PMID:27303717

Expression of plectasin in Pichia pastoris and its characterization as a new antimicrobial peptide against Staphyloccocus and Streptococcus.

PubMed

Zhang, Jun; Yang, Yalin; Teng, Da; Tian, Zigang; Wang, Shaoran; Wang, Jianhua

2011-08-01

Recombinant plectasin, the first fungus defensin, was expressed in Pichia pastoris and purified, and its physical, chemical and antimicrobial characteristics were studied. Following a 120 h induction of recombinant yeast, the amount of total secreted protein reached 748.63 μg/ml. The percentage of recombinant plectasin was estimated to be 71.79% of the total protein. After purification with a Sephadex G-25 column and RP-HPLC, the identity of plectasin was verified by MALDI-TOF MS. Plectasin exhibited strong antimicrobial activity against the Gram-positive bacteria Staphyloccocusaureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Streptococcus suis. At a concentration of 2560 μg/ml, this peptide showed approximately equal activity against S. aureus, S. epidermidis, S. suis, and S. pneumoniae, when compared to 320 μg/ml vancomycin, 640 μg/ml penicillin, 320 μg/ml vancomycin and 160 μg/ml vancomycin, respectively. In addition, plectasin showed anti-S. aureus activity over a wide pH range of 2.0 and 10.0, a high thermal stability at 100 °C for 1h and remarkable resistance to papain and pepsin. The expression and characterization of recombinant plectasin in P. pastoris has potential to treat Streptococcus and Staphyloccocus infections when most traditional antibiotics show no effect on them. Our results indicate that plectasin can be produced in large quantities, and that it has pharmaceutical importance for the prevention and clinical treatment of Staphyloccocus and Streptococcus infections. Copyright © 2011 Elsevier Inc. All rights reserved.

Permanent Central Diabetes Insipidus as a Complication of S. pneumoniae Meningitis in the Pediatric Population.

PubMed

Statz, Hannah; Hsu, Benson S

2016-05-01

Diabetes insipidus is a rare but recognized complication of meningitis. The occurrence of diabetes insidipus has been previously attributed to Streptococcus pneumoniae (S. pneumoniae) in a handful of patients and only once within the pediatric subpopulation. We present the clinical course of a previously healthy 2-year, 8-month-old male child ultimately diagnosed with central diabetes insipidus (CDI) secondary to S. pneumoniae meningitis. Permanent CDI following S. pneumoniae meningitis is unique to our case and has not been previously described. Following the case presentation, we describe the etiology, pathophysiology, diagnosis, and treatment of CDI. The mechanism proposed for this clinical outcome is cerebral herniation for a sufficient duration and subsequent ischemia leading to the development of permanent CDI. Providers should be aware of CDI resulting from S. pneumoniae meningitis as prompt diagnosis and management may decrease the risk of permanent hypothalamo-pituitary axis damage. Copyright© South Dakota State Medical Association.

Molecular Detection of Streptococcus pneumoniae on Dried Blood Spots from Febrile Nigerian Children Compared to Culture.

PubMed

Iroh Tam, Pui-Ying; Hernandez-Alvarado, Nelmary; Schleiss, Mark R; Hassan-Hanga, Fatimah; Onuchukwu, Chuma; Umoru, Dominic; Obaro, Stephen K

2016-01-01

Nigeria has one of the highest burdens of pneumococcal disease in the world, but accurate surveillance is lacking. Molecular detection of infectious pathogens in dried blood spots (DBS) is an ideal method for surveillance of infections in resource-limited settings because of its low cost, minimal blood volumes involved, and ease of storage at ambient temperature. Our study aim was to evaluate a Streptococcus pneumoniae real-time polymerase chain reaction (rt-PCR) assay on DBS from febrile Nigerian children on Whatman 903 and FTA filter papers, compared to the gold standard of culture. Between September 2011 to May 2015, blood was collected from children 5 years of age or under who presented to six hospital study sites throughout northern and central Nigeria with febrile illness, and inoculated into blood culture bottles or spotted onto Whatman 903 or FTA filter paper. Culture and rt-PCR were performed on all samples. A total of 537 DBS specimens from 535 children were included in the study, of which 15 were culture-positive for S. pneumoniae. The rt-PCR assay detected S. pneumoniae in 12 DBS specimens (2.2%). One positive rt-PCR result was identified in a culture-negative specimen from a high-risk subject, and two positive rt-PCR results were negative on repeat testing. Six culture-confirmed cases of S. pneumoniae bacteremia were missed. Compared to culture, the overall sensitivities of Whatman 903 and FTA DBS for detection of S. pneumoniae were 57.1% (95% CI 18.4-90.1%) and 62.5% (95% CI 24.5-91.5%), respectively. Nonspecific amplification was noted in an additional 22 DBS (4.1%). Among these, six were positive for a non-S. pneumoniae pathogen on culture. Rt-PCR was able to detect S. pneumoniae from clinical DBS specimens, including from a culture-negative specimen. Our findings show promise of this approach as a surveillance diagnostic, but also raise important cautionary questions. Several DBS specimens were detected as S. pneumoniae by rt-PCR despite growth of a non-S. pneumoniae pathogen on culture. A precise definition of what constitutes a positive result is required to avoid falsely over-identifying specimens.

The α-Tocopherol Form of Vitamin E Reverses Age-Associated Susceptibility to Streptococcus pneumoniae Lung Infection by Modulating Pulmonary Neutrophil Recruitment

PubMed Central

Ghanem, Elsa N. Bou; Clark, Stacie; Du, Xiaogang; Wu, Dayong; Camilli, Andrew; Leong, John M.; Meydani, Simin N.

2016-01-01

Streptococcus pneumoniae infections are an important cause of morbidity and mortality in older patients. Uncontrolled neutrophil-driven pulmonary inflammation exacerbates this disease. To test whether the α-tocopherol (α-Toc) form of vitamin E, a regulator of immunity, can modulate neutrophil responses as a preventive strategy to mitigate the age-associated decline in resistance to S. pneumoniae, young (4 mo) and old (22–24 mo) C57BL/6 mice were fed a diet containing 30-PPM (control) or 500-PPM (supplemented) α-Toc for 4 wk and intratracheally infected with S. pneumoniae. Aged mice fed a control diet were exquisitely more susceptible to S. pneumoniae than young mice. At 2 d postinfection, aged mice suffered 1000-fold higher pulmonary bacterial burden, 2.2-fold higher levels of neutrophil recruitment to the lung, and a 2.25-fold higher rate of lethal septicemia. Strikingly, α-Toc supplementation of aged mice resulted in a 1000-fold lower bacterial lung burden and full control of infection. This α-Toc–induced resistance to pneumococcal challenge was associated with a 2-fold fewer pulmonary neutrophils, a level comparable to S. pneumoniae–challenged, conventionally fed young mice. α-Toc directly inhibited neutrophil egress across epithelial cell monolayers in vitro in response to pneumococci or hepoxilin-A3, an eicosanoid required for pneumococcus-elicited neutrophil trans-epithelial migration. α-Toc altered expression of multiple epithelial and neutrophil adhesion molecules involved in migration, including CD55, CD47, CD18/CD11b, and ICAM-1. These findings suggest that α-Toc enhances resistance of aged mice to bacterial pneumonia by modulating the innate immune response, a finding that has potential clinical significance in combating infection in aged individuals through nutritional intervention. PMID:25512603

Validation of the Infectious Diseases Society of America/American Thoracic Society criteria to predict severe community-acquired pneumonia caused by Streptococcus pneumoniae.

PubMed

Kontou, Paschalina; Kuti, Joseph L; Nicolau, David P

2009-10-01

Severe community-acquired pneumonia (CAP) is usually defined as pneumonia that requires intensive care unit (ICU) admission; the primary pathogen responsible for ICU admission is Streptococcus pneumoniae. In this study, the 2007 Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) consensus criteria for ICU admission were compared with other severity scores in predicting ICU admission and mortality. We retrospectively studied 158 patients with pneumococcal CAP (1999-2003). Clinical and laboratory features at the emergency department were recorded and used to calculate the 2007 IDSA/ATS rule, the 2001 ATS rule, 2 modified 2007 IDSA/ATS rules, the Pneumonia Severity Index (PSI), and the CURB (confusion, urea, respiratory rate, blood pressure) score. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were assessed for the various indices. We also determined the criteria that were independently predictive of ICU admission and of mortality in our population. The 2007 IDSA/ATS criteria performed as well as the 2001 ATS rule in predicting ICU admission both demonstrated high sensitivity (90%) and NPV (97%). For the prediction of mortality, the best tool proved to be the PSI score (sensitivity, 95%; NPV, 99%). The variables associated with ICU admission in this patient population included tachypnea, confusion, Pao(2)/Fio(2) ratio of 250 or lower, and hypotension requiring fluid resuscitation. Mechanical ventilation and PSI class V were independently associated with mortality. This study confirms the usefulness of the new criteria in predicting severe CAP. The 2001 ATS criteria seem an attractive alternative because they are simple and as effective as the 2007 IDSA/ATS criteria.

Eradication of pathogens from the nasopharynx after therapy of acute maxillary sinusitis with low- or high-dose amoxicillin/clavulanic acid.

PubMed

Brook, Itzhak; Foote, Perry A; Hausfeld, Jeffrey N

2005-11-01

The growing resistance of Streptococcus pneumoniae to penicillin can be overcome by increasing the dose of the penicillin administered. This generated the recommendation that the adult dose of amoxicillin for the treatment of acute maxillary sinusitis (AMS) be increased from 1.5 g/day to 4.0 g/day. The objective of this study was to investigate whether the higher dose of amoxicillin is more effective than the previously recommended dose in eradicating S. pneumoniae from the nasopharynx of patients who present with AMS. Nasopharyngeal cultures obtained from 58 patients with AMS were studied: 30 received amoxicillin 1.5 g/day given in divided doses three times a day for 10 days (amoxicillin/clavulanic acid 4:1 formulation) and 28 were treated with amoxicillin 4.0 g/day given in divided doses twice a day for 10 days (amoxicillin/clavulanic acid 16:1 formulation). Seventy-one potentially pathogenic organisms were isolated: S. pneumoniae (27 isolates), Haemophilus influenzae non-type b (25), Moraxella catarrhalis (5), Streptococcus pyogenes (5) and Staphylococcus aureus (9). The number of S. pneumoniae isolates in the 1.5 g/day group was reduced from 14 to 9 (2 intermediately resistant and 3 highly resistant). In contrast, the number of S. pneumoniae isolates in the 4.0 g/day group was reduced from 13 to 2 (1 highly resistant) (P<0.05). No differences were noted in the eradication rate of other groups of isolates, which were all susceptible to amoxicillin/clavulanic acid. These data illustrate the superiority of 4.0 g/day amoxicillin/clavulanic acid compared with 1.5 g/day amoxicillin/clavulanic acid in the eradication of S. pneumoniae from the nasopharynx.

Respiratory comorbidities and risk of mortality in hospitalized patients with idiopathic pulmonary fibrosis.

PubMed

Oda, Keishi; Yatera, Kazuhiro; Fujino, Yoshihisa; Kido, Takashi; Hanaka, Tetsuya; Sennari, Konomi; Fushimi, Kiyohide; Matsuda, Shinya; Mukae, Hiroshi

2018-01-01

Respiratory comorbidities are frequently associated with idiopathic pulmonary fibrosis (IPF). However, little is known about their prognostic impact in hospitalized patients with IPF. We examined the impact of respiratory comorbidities on the mortality rates of hospitalized patients with IPF using a Japanese nationwide database. We identified 5665 hospitalized patients diagnosed with IPF between April 2010 and March 2013. The primary outcome was defined as the in-hospital mortality at 30 days after admission. The impact of respiratory comorbidities was assessed using a Cox proportional hazards model that incorporated clinically relevant factors. In hospitalized patients with IPF, the prevalence of bacterial pneumonia, pulmonary hypertension, and lung cancer were 9.5%, 4.6%, and 3.7%, respectively. Among patients with bacterial pneumonia, the four most common pathogens were Streptococcus pneumoniae (31.6%), methicillin-resistant Streptococcus aureus (18.4%), Klebsiella pneumoniae (9.2%), and Pseudomonas aeruginosa (9.2%). Lung cancer was more commonly found in the lower lobes (60.1%) than in other lobes. The survival at 30 days from admission was 78.4% in all patients and significantly lower in IPF patients with bacterial pneumonia (adjusted hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.04-1.63; p < 0.023) and patients with lung cancer (adjusted HR, 1.99; 95% CI, 1.47-2.69; p < 0.001) than in others. Pulmonary hypertension was not associated with mortality. IPF patients with one or more of these three respiratory comorbidities had a poorer survival than others (p < 0.05). Respiratory comorbidities, especially bacterial pneumonia and lung cancer, influence mortality in hospitalized patients with IPF. Copyright © 2017 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

Lobar pneumonia treated by Musgrave Park physicians.

PubMed

Hedley-Whyte, John; Milamed, Debra R

2009-05-01

In the decade 1935-45 the treatment of lobar pneumonia in the developed and warring world underwent a series of evolutions-anti-sera, specific anti-sera, refinement of sulpha drugs, sulpha and anti-sera, the introduction of penicillin for bacteriology, then ophthalmology, and then for penicillin-sensitive bacterial infections such as lobar pneumonia with its many Cooper types of Streptococcus pneumoniae. Penicillin for civilian use was essentially banned in World War II, a ban that early in 1941 two Musgrave Park physicians tried to circumvent. Strict secrecy on the details of penicillin production was enforced. The treatment option chosen by the Musgrave Park physicians in 1941, and the non-availability of penicillin led to sequelae affecting the post-Belfast careers of both patient and physicians.

Characteristics and Outcome of Streptococcus pneumoniae Endocarditis in the XXI Century

PubMed Central

de Egea, Viviana; Muñoz, Patricia; Valerio, Maricela; de Alarcón, Arístides; Lepe, José Antonio; Miró, José M.; Gálvez-Acebal, Juan; García-Pavía, Pablo; Navas, Enrique; Goenaga, Miguel Angel; Fariñas, María Carmen; Vázquez, Elisa García; Marín, Mercedes; Bouza, Emilio

2015-01-01

Abstract Streptococcus pneumoniae is an infrequent cause of severe infectious endocarditis (IE). The aim of our study was to describe the epidemiology, clinical and microbiological characteristics, and outcome of a series of cases of S. pneumoniae IE diagnosed in Spain and in a series of cases published since 2000 in the medical literature. We prospectively collected all cases of IE diagnosed in a multicenter cohort of patients from 27 Spanish hospitals (n = 2539). We also performed a systematic review of the literature since 2000 and retrieved all cases with complete clinical data using a pre-established protocol. Predictors of mortality were identified using a logistic regression model. We collected 111 cases of pneumococcal IE: 24 patients from the Spanish cohort and 87 cases from the literature review. Median age was 51 years, and 23 patients (20.7%) were under 15 years. Men accounted for 64% of patients, and infection was community-acquired in 96.4% of cases. The most important underlying conditions were liver disease (27.9%) and immunosuppression (10.8%). A predisposing heart condition was present in only 18 patients (16.2%). Pneumococcal IE affected a native valve in 93.7% of patients. Left-sided endocarditis predominated (aortic valve 53.2% and mitral valve 40.5%). The microbiological diagnosis was obtained from blood cultures in 84.7% of cases. In the Spanish cohort, nonsusceptibility to penicillin was detected in 4.2%. The most common clinical manifestations included fever (71.2%), a new heart murmur (55%), pneumonia (45.9%), meningitis (40.5%), and Austrian syndrome (26.1%). Cardiac surgery was performed in 47.7% of patients. The in-hospital mortality rate was 20.7%. The multivariate analysis revealed the independent risk factors for mortality to be meningitis (OR, 4.3; 95% CI, 1.4–12.9; P < 0.01). Valve surgery was protective (OR, 0.1; 95% CI, 0.04–0.4; P < 0.01). Streptococcus pneumoniae IE is a community-acquired disease that mainly affects native aortic valves. Half of the cases in the present study had concomitant pneumonia, and a considerable number developed meningitis. Mortality was high, mainly in patients with central nervous system (CNS) involvement. Surgery was protective. PMID:26426629

Characteristics and Outcome of Streptococcus pneumoniae Endocarditis in the XXI Century: A Systematic Review of 111 Cases (2000-2013).

PubMed

de Egea, Viviana; Muñoz, Patricia; Valerio, Maricela; de Alarcón, Arístides; Lepe, José Antonio; Miró, José M; Gálvez-Acebal, Juan; García-Pavía, Pablo; Navas, Enrique; Goenaga, Miguel Angel; Fariñas, María Carmen; Vázquez, Elisa García; Marín, Mercedes; Bouza, Emilio

2015-09-01

Streptococcus pneumoniae is an infrequent cause of severe infectious endocarditis (IE). The aim of our study was to describe the epidemiology, clinical and microbiological characteristics, and outcome of a series of cases of S. pneumoniae IE diagnosed in Spain and in a series of cases published since 2000 in the medical literature. We prospectively collected all cases of IE diagnosed in a multicenter cohort of patients from 27 Spanish hospitals (n = 2539). We also performed a systematic review of the literature since 2000 and retrieved all cases with complete clinical data using a pre-established protocol. Predictors of mortality were identified using a logistic regression model. We collected 111 cases of pneumococcal IE: 24 patients from the Spanish cohort and 87 cases from the literature review. Median age was 51 years, and 23 patients (20.7%) were under 15 years. Men accounted for 64% of patients, and infection was community-acquired in 96.4% of cases. The most important underlying conditions were liver disease (27.9%) and immunosuppression (10.8%). A predisposing heart condition was present in only 18 patients (16.2%). Pneumococcal IE affected a native valve in 93.7% of patients. Left-sided endocarditis predominated (aortic valve 53.2% and mitral valve 40.5%). The microbiological diagnosis was obtained from blood cultures in 84.7% of cases. In the Spanish cohort, nonsusceptibility to penicillin was detected in 4.2%. The most common clinical manifestations included fever (71.2%), a new heart murmur (55%), pneumonia (45.9%), meningitis (40.5%), and Austrian syndrome (26.1%). Cardiac surgery was performed in 47.7% of patients. The in-hospital mortality rate was 20.7%. The multivariate analysis revealed the independent risk factors for mortality to be meningitis (OR, 4.3; 95% CI, 1.4-12.9; P < 0.01). Valve surgery was protective (OR, 0.1; 95% CI, 0.04-0.4; P < 0.01). Streptococcus pneumoniae IE is a community-acquired disease that mainly affects native aortic valves. Half of the cases in the present study had concomitant pneumonia, and a considerable number developed meningitis. Mortality was high, mainly in patients with central nervous system (CNS) involvement. Surgery was protective.

False no-growth blood cultures in pneumococcal pneumonia.

PubMed Central

Adeniyi-Jones, C C; Stevens, D L; Rasquinha, E S

1980-01-01

The growth of Streptococcus pneumoniae in commercial media containing 14C-labeled substrates was studied experimentally; the results of blood cultures that were positive for S. pneumoniae over a 14-month period were analyzed to explain no-growth but radiometrically positive blood cultures from four patients with clinically diagnosed pneumococcal pneumonia. The growth of S. pneumonoiae in aerobic blood culture vials resulted in a chocolate color in the medium. S. pneumoniae grew rapidly in both aerobic and anaerobic media, but 14CO2 evolved from the metabolism of the labeled substrates was detected only in the aerobic culture vials. Radiometric detection lagged behind growth of the organisms and was accompanied by visual changes in the media. By 24 h, the viability of the culture was on the decline; radiometric readings remained positive even when the culture had died. PMID:7419708

Effect of Xylitol on Growth of Streptococcus pneumoniae in the Presence of Fructose and Sorbitol

PubMed Central

Tapiainen, Terhi; Kontiokari, Tero; Sammalkivi, Laura; Ikäheimo, Irma; Koskela, Markku; Uhari, Matti

2001-01-01

Xylitol is effective in preventing acute otitis media by inhibiting the growth of Streptococcus pneumoniae. To clarify this inhibition we used fructose, which is known to block similar growth inhibition observed in Streptococcus mutans. In addition, we evaluated the efficacy of sorbitol in inhibiting the growth of pneumococci, as sorbitol is widely used for indications similar to those for which xylitol is used. The addition of 5% xylitol to the growth medium resulted in marked growth inhibition, an effect which was totally eliminated in the presence of 1, 2.5, or 5% fructose but not in the presence of 1 or 5% glucose, 1% galactose, or 1% sucrose. This finding implies that xylitol-induced inhibition of pneumococcal growth is mediated via the fructose phosphotransferase system in a way similar to that in which mutans group streptococcal growth is inhibited. The addition of sorbitol at concentrations of 1, 2.5, or 5% to the growth medium did not affect the growth of pneumococci and neither inhibited nor enhanced the xylitol-induced growth impairment. Thus, it seems that xylitol is the only commercially used sugar substitute proven to have an antimicrobial effect on pneumococci. PMID:11120960

Antimicrobial resistance in Hispanic patients hospitalized in San Antonio, TX with community-acquired pneumonia.

PubMed

Restrepo, Marcos I; Velez, Maria I; Serna, Gloria; Anzueto, Antonio; Mortensen, Eric M

2010-11-01

Limited information is available on the antimicrobial resistance of patients with community-acquired pneumonia (CAP) depending on their ethnicity. Our aim was to compare the clinical characteristics, etiology, and microbiological resistance of Hispanic versus non-Hispanic white patients. A retrospective cohort of 601 patients with a diagnosis of CAP included 288 non-Hispanic whites and 313 Hispanics. Penicillin-resistant Streptococcus pneumoniae was more common among Hispanic patients (21.7% vs 0%; P=0.03) but there were no significant differences in macrolide-resistant S pneumoniae, drug-resistant S pneumoniae, or potential or actual multidrug-resistant pathogens (eg, drug-resistant S pneumoniae, methicillin-resistant Staphylococcus aureus, Pseudomonas spp., and Acinetobacter spp.). There were no differences among groups in length of hospital stay, intensive care unit (ICU) admission, or 30-day mortality. This study suggests that Hispanic patients with CAP have a higher rate of penicillin-resistant S pneumoniae, but no differences in antimicrobial resistance, 30-day mortality, ICU admission, or length of stay when compared with non-Hispanic white patients.

Cross-over assessment of serum bactericidal activity of moxifloxacin and levofloxacin versus penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae in healthy volunteers.

PubMed

Hart, Daniel; Weinstein, Melvin P

2007-07-01

We compared the serum bactericidal activity (SBA) of moxifloxacin and levofloxacin against penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae in 12 healthy volunteers. Each subject received 3 days of oral moxifloxacin 400 mg daily and levofloxacin 750 mg daily, respectively, with a 2- to 4-week washout period between regimens. Blood was drawn at 6 time points after the third dose of each antibiotic. Mean serum bactericidal titers (MSBTRs) for moxifloxacin were 4-fold higher than the mean titers for levofloxacin at each time point. For each drug, MSBTRs at each time point were the same or within one 2-fold dilution when analyzed according to the penicillin susceptibility of the strains or the sex of the subjects. The difference in SBA of the 2 drugs may have implications for the emergence of resistance and clinical outcome.

[Real-time PCR detection of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae DNA in clinical specimens].

PubMed

Vacková, Z; Lžičařová, D; Stock, N K; Kozáková, J

2015-10-01

The study aim was to implement a molecular real-time polymerase chain reaction (PCR) assay recommended by the CDC (Centers for Disease Control and Prevention) for the detection of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae in clinical (culture negative) specimens from patients with suspected invasive bacterial disease. Clinical specimens are referred to the National Reference Laboratory (NRL) for Meningococcal Infections, Unit for Airborne Bacterial Infections, Centre for Epidemiology and Microbiology, National Institute of Public Health from various regions of the Czech Republic. Clinical specimens are, in particular, cerebrospinal fluid, anti-coagulated blood or serum and, exceptionally, post-mortem specimens. The NRL has implemented molecular diagnosis of these bacterial pathogens involved in meningitis and sepsis from clinical specimens since 1999. The first diagnostic method was semi-nested PCR followed by electrophoretic analysis. In 2014, a molecular qualitative real-time PCR assay was implemented.

Novel PCR-Restriction Fragment Length Polymorphism Method for Determining Serotypes or Serogroups of Streptococcus pneumoniae Isolates

PubMed Central

Batt, Sarah L.; Charalambous, Bambos M.; McHugh, Timothy D.; Martin, Siobhan; Gillespie, Stephen H.

2005-01-01

Serotyping Streptococcus pneumoniae is a technique generally confined to reference laboratories, as purchasing pneumococcal antisera is a huge investment. Many attempts have been made to modify serological agglutination techniques to make them more accessible, and more recently developments in serotyping have focused on molecular techniques. This paper describes a PCR assay which amplifies the entire capsulation locus between dexB and aliA. Amplicons are digested to produce serotype-specific patterns. We have shown, using 81 epidemiologically unrelated strains representing 46 different serotypes, that the patterns correlate with a 90 to 100% similarity range for the same serotype or serogroup. Prospective testing of 73 isolates of unknown serotype confirmed reliable serotype attribution, and serotype profiles are reproducible on repeated testing. Once our database contains all 90 serotypes, this technique should be fully portable, cost-effective, and useful in any laboratory with sufficient molecular experience. PMID:15956380

Mechanisms and impact of genetic recombination in the evolution of Streptococcus pneumoniae

PubMed Central

Chaguza, Chrispin; Cornick, Jennifer E.; Everett, Dean B.

2015-01-01

Streptococcus pneumoniae (the pneumococcus) is a highly recombinogenic bacterium responsible for a high burden of human disease globally. Genetic recombination, a process in which exogenous DNA is acquired and incorporated into its genome, is a key evolutionary mechanism employed by the pneumococcus to rapidly adapt to selective pressures. The rate at which the pneumococcus acquires genetic variation through recombination is much higher than the rate at which the organism acquires variation through spontaneous mutations. This higher rate of variation allows the pneumococcus to circumvent the host innate and adaptive immune responses, escape clinical interventions, including antibiotic therapy and vaccine introduction. The rapid influx of whole genome sequence (WGS) data and the advent of novel analysis methods and powerful computational tools for population genetics and evolution studies has transformed our understanding of how genetic recombination drives pneumococcal adaptation and evolution. Here we discuss how genetic recombination has impacted upon the evolution of the pneumococcus. PMID:25904996

Mechanisms and impact of genetic recombination in the evolution of Streptococcus pneumoniae.

PubMed

Chaguza, Chrispin; Cornick, Jennifer E; Everett, Dean B

2015-01-01

Streptococcus pneumoniae (the pneumococcus) is a highly recombinogenic bacterium responsible for a high burden of human disease globally. Genetic recombination, a process in which exogenous DNA is acquired and incorporated into its genome, is a key evolutionary mechanism employed by the pneumococcus to rapidly adapt to selective pressures. The rate at which the pneumococcus acquires genetic variation through recombination is much higher than the rate at which the organism acquires variation through spontaneous mutations. This higher rate of variation allows the pneumococcus to circumvent the host innate and adaptive immune responses, escape clinical interventions, including antibiotic therapy and vaccine introduction. The rapid influx of whole genome sequence (WGS) data and the advent of novel analysis methods and powerful computational tools for population genetics and evolution studies has transformed our understanding of how genetic recombination drives pneumococcal adaptation and evolution. Here we discuss how genetic recombination has impacted upon the evolution of the pneumococcus.

Structural basis for the substrate specificity of PepA from Streptococcus pneumoniae, a dodecameric tetrahedral protease.

PubMed

Kim, Doyoun; San, Boi Hoa; Moh, Sang Hyun; Park, Hyejin; Kim, Dong Young; Lee, Sangho; Kim, Kyeong Kyu

2010-01-01

Regulated cytosolic proteolysis is one of the key cellular processes ensuring proper functioning of a cell. M42 family proteases show a broad spectrum of substrate specificities, but the structural basis for such diversity of the substrate specificities is lagging behind biochemical data. Here we report the crystal structure of PepA from Streptococcus pneumoniae, a glutamyl aminopeptidase belonging to M42 family (SpPepA). We found that Arg-257 in the substrate binding pocket is strategically positioned so that Arg-257 can make electrostatic interactions with the acidic residue of a substrate at its N-terminus. Structural comparison of the substrate binding pocket of the M42 family proteases, along with the structure-based multiple sequence alignment, argues that the appropriate electrostatic interactions contribute to the selective substrate specificity of SpPepA. Copyright 2009 Elsevier Inc. All rights reserved.

Spondylodiskitis secondary to Streptococcus equi subspecies zooepidemicus.

PubMed

Bhatia, Ravi; Bhanot, Nitin

2012-01-01

Streptococcus equi subspecies zooepidemicus, traditionally classified under Group C Streptococci, is primarily a veterinary pathogen. Rarely, it may cause infections such as bacteremia, meningitis, endocarditis and pneumonia in humans. Musculoskeletal infections secondary to this pathogen are very uncommon. The authors present the first case of osteomyelitis due to S. zooepidemicus in a farmer who had close contact with a dead horse. The authors review all cases of osteoarticular infections secondary to this microbe, in addition to providing an overview of clinical manifestations, treatment and outcome of this infection.

IL-22 Defect During Streptococcus pneumoniae Infection Triggers Exacerbation of Chronic Obstructive Pulmonary Disease.

PubMed

Pichavant, Muriel; Sharan, Riti; Le Rouzic, Olivier; Olivier, Cécile; Hennegrave, Florence; Rémy, Gaëlle; Pérez-Cruz, Magdiel; Koné, Bachirou; Gosset, Pierre; Just, Nicolas; Gosset, Philippe

2015-11-01

Progression of chronic obstructive pulmonary disease (COPD) is linked to episodes of exacerbations caused by bacterial infections due to Streptococcus pneumoniae. Our objective was to identify during COPD, factors of susceptibility to bacterial infections among cytokine network and their role in COPD exacerbations. S. pneumoniae was used to sub-lethally challenge mice chronically exposed to air or cigarette smoke (CS) and to stimulate peripheral blood mononuclear cells (PBMC) from non-smokers, smokers and COPD patients. The immune response and the cytokine production were evaluated. Delayed clearance of the bacteria and stronger lung inflammation observed in infected CS-exposed mice were associated with an altered production of IL-17 and IL-22 by innate immune cells. This defect was related to a reduced production of IL-1β and IL-23 by antigen presenting cells. Importantly, supplementation with recombinant IL-22 restored bacterial clearance in CS-exposed mice and limited lung alteration. In contrast with non-smokers, blood NK and NKT cells from COPD patients failed to increase IL-17 and IL-22 levels in response to S. pneumoniae, in association with a defect in IL-1β and IL-23 secretion. This study identified IL-17 and IL-22 as susceptibility factors in COPD exacerbation. Therefore targeting such cytokines could represent a potent strategy to control COPD exacerbation.

Rational Manipulation of mRNA Folding Free Energy Allows Rheostat Control of Pneumolysin Production by Streptococcus pneumoniae

PubMed Central

Amaral, Fábio E.; Parker, Dane; Randis, Tara M.; Kulkarni, Ritwij; Prince, Alice S.; Shirasu-Hiza, Mimi M.; Ratner, Adam J.

2015-01-01

The contribution of specific factors to bacterial virulence is generally investigated through creation of genetic “knockouts” that are then compared to wild-type strains or complemented mutants. This paradigm is useful to understand the effect of presence vs. absence of a specific gene product but cannot account for concentration-dependent effects, such as may occur with some bacterial toxins. In order to assess threshold and dose-response effects of virulence factors, robust systems for tunable expression are required. Recent evidence suggests that the folding free energy (ΔG) of the 5’ end of mRNA transcripts can have a significant effect on translation efficiency and overall protein abundance. Here we demonstrate that rational alteration of 5’ mRNA folding free energy by introduction of synonymous mutations allows for predictable changes in pneumolysin (PLY) expression by Streptococcus pneumoniae without the need for chemical inducers or heterologous promoters. We created a panel of isogenic S. pneumoniae strains, differing only in synonymous (silent) mutations at the 5’ end of the PLY mRNA that are predicted to alter ΔG. Such manipulation allows rheostat-like control of PLY production and alters the cytotoxicity of whole S. pneumoniae on primary and immortalized human cells. These studies provide proof-of-principle for further investigation of mRNA ΔG manipulation as a tool in studies of bacterial pathogenesis. PMID:25798590

[Classical and new approaches in laboratory diagnosis of viridans streptococci].

PubMed

Ergin, Alper

2010-07-01

Viridans group streptococci (VGS) are gram-positive microorganisms that can form alpha-hemolytic colonies on sheep blood agar. They reside as normal flora in oral cavity, respiratory, gastrointestinal, urogenital tract and on skin. They can cause bacteremia, endocarditis, meningitis and septicemia following dental procedures. The diagnosis of VGS are difficult since the taxonomic classification and species na-mes may change due in time. Viridans group streptococci are classified into 5 groups (Sanguinis, Mitis, Mutans, Salivarius, Anginosus) according to biochemical reactions and 16S rRNA sequencing. Since Streptococcus pneumoniae is a member of the Mitis group, the other important species in this group deserves investigation. Genetic exchange between Streptococcus mitis, Streptococcus oralis and S.pneumoniae by transformation and lysis mechanisms occur continously as they share the same anatomical region. These mechanisms play role in exchanging capsular and antibiotic resistance genes between these species. The cultivation of VGS usually starts with the inoculation of various patient specimens into sheep blood agar and the detection of alpha-hemolytic colonies. Observation of gram-positive cocci microscopically, the detection of optochin-resistant and bile insoluble colonies with few exceptions are the further important steps in laboratory diagnosis. VGS are then identified at species level by using biochemical reactions, automated diagnostic systems and molecular methods. The last step in the laboratory diagnosis of VGS is antibiotic susceptibility testing which is of outmost importance as penicillin and erythromycin resistance are on rise. In this review article, classification of VGS, similarities between S.pneumoniae and Mitis group streptococci and the laboratory diagnosis of VGS have been discussed.

CRH Affects the Phenotypic Expression of Sepsis-Associated Virulence Factors by Streptococcus pneumoniae Serotype 1 In vitro

PubMed Central

Ngo Ndjom, Colette G.; Kantor, Lindsay V.; Jones, Harlan P.

2017-01-01

Sepsis is a life-threatening health condition caused by infectious pathogens of the respiratory tract, and accounts for 28–50% of annual deaths in the US alone. Current treatment regimen advocates the use of corticosteroids as adjunct treatment with antibiotics, for their broad inhibitory effect on the activity and production of pro-inflammatory mediators. However, despite their use, corticosteroids have not proven to be able to reverse the death incidence among septic patients. We have previously demonstrated the potential for neuroendocrine factors to directly influence Streptococcus pneumoniae virulence, which may in turn mediate disease outcome leading to sepsis and septic shock. The current study investigated the role of Corticotropin-releasing hormone (CRH) in mediating key markers of pneumococcal virulence as important phenotypic determinants of sepsis and septic shock risks. In vitro cultures of serotype 1 pneumococcal strain with CRH promoted growth rate, increased capsule thickness and penicillin resistance, as well as induced pneumolysin gene expression. These results thus provide significant insights of CRH–pathogen interactions useful in understanding the underlying mechanisms of neuroendocrine factor's role in the onset of community acquired pneumonias (CAP), sepsis and septic shock. PMID:28690980

ParC subunit of DNA topoisomerase IV of Streptococcus pneumoniae is a primary target of fluoroquinolones and cooperates with DNA gyrase A subunit in forming resistance phenotype.

PubMed Central

Muñoz, R; De La Campa, A G

1996-01-01

The genes encoding the ParC and ParE subunits of topoisomerase IV of Streptococcus pneumoniae, together with the region encoding amino acids 46 to 172 (residue numbers are as in Escherichia coli) of the pneumococcal GyrA subunit, were partially characterized. The gyrA gene maps to a physical location distant from the gyrB and parC loci on the chromosome, whereas parC is closely linked to parE. Ciprofloxacin-resistant (Cpr) clinical isolates of S. pneumoniae had mutations affecting amino acid residues of the quinolone resistance-determining region of ParC (low-level Cpr) or in both quinolone resistance-determining regions of ParC and GyrA (high-level Cpr). Mutations were found in residue positions equivalent to the serine at position 83 and the aspartic acid at position 87 of the E. coli GyrA subunit. Transformation experiments suggest that ParC is the primary target of ciprofloxacin. Mutation in parC appears to be a prerequisite before mutations in gyrA can influence resistance levels. PMID:8891124

Mechanisms of Dexamethasone-Mediated Inhibition of Toll-Like Receptor Signaling Induced by Neisseria meningitidis and Streptococcus pneumoniae▿

PubMed Central

Mogensen, Trine H.; Berg, Randi S.; Paludan, Søren R.; Østergaard, Lars

2008-01-01

Excessive inflammation contributes to the pathogenesis of bacterial meningitis, which remains a serious disease despite treatment with antibiotics. Therefore, anti-inflammatory drugs have important therapeutic potential, and clinical trials have revealed that early treatment with dexamethasone significantly reduces mortality and morbidity from bacterial meningitis. Here we investigate the molecular mechanisms behind the inhibitory effect of dexamethasone upon the inflammatory responses evoked by Neisseria meningitidis and Streptococcus pneumoniae, two of the major causes of bacterial meningitis. The inflammatory cytokine response was dependent on Toll-like receptor signaling and was strongly inhibited by dexamethasone. Activation of the NF-κB pathway was targeted at several levels, including inhibition of IκB phosphorylation and NF-κB DNA-binding activity as well as upregulation of IκBα synthesis. Our data also revealed that the timing of steroid treatment relative to infection was important for achieving strong inhibition, particularly in response to S. pneumoniae. Altogether, we describe important targets of dexamethasone in the inflammatory responses evoked by N. meningitidis and S. pneumoniae, which may contribute to our understanding of the clinical effect and the importance of timing with respect to corticosteroid treatment during bacterial meningitis. PMID:17938219

The post-vaccine microevolution of invasive Streptococcus pneumoniae

PubMed Central

Cremers, Amelieke J. H.; Mobegi, Fredrick M.; de Jonge, Marien I.; van Hijum, Sacha A. F. T.; Meis, Jacques F.; Hermans, Peter W. M.; Ferwerda, Gerben; Bentley, Stephen D.; Zomer, Aldert L.

2015-01-01

The 7-valent pneumococcal conjugated vaccine (PCV7) has affected the genetic population of Streptococcus pneumoniae in pediatric carriage. Little is known however about pneumococcal population genomics in adult invasive pneumococcal disease (IPD) under vaccine pressure. We sequenced and serotyped 349 strains of S. pneumoniae isolated from IPD patients in Nijmegen between 2001 and 2011. Introduction of PCV7 in the Dutch National Immunization Program in 2006 preluded substantial alterations in the IPD population structure caused by serotype replacement. No evidence could be found for vaccine induced capsular switches. We observed that after a temporary bottleneck in gene diversity after the introduction of PCV7, the accessory gene pool re-expanded mainly by genes already circulating pre-PCV7. In the post-vaccine genomic population a number of genes changed frequency, certain genes became overrepresented in vaccine serotypes, while others shifted towards non-vaccine serotypes. Whether these dynamics in the invasive pneumococcal population have truly contributed to invasiveness and manifestations of disease remains to be further elucidated. We suggest the use of whole genome sequencing for surveillance of pneumococcal population dynamics that could give a prospect on the course of disease, facilitating effective prevention and management of IPD. PMID:26492862

Evidence for Human Streptococcus pneumoniae in wild and captive chimpanzees: A potential threat to wild populations.

PubMed

Köndgen, Sophie; Calvignac-Spencer, Sebastien; Grützmacher, Kim; Keil, Verena; Mätz-Rensing, Kerstin; Nowak, Kathrin; Metzger, Sonja; Kiyang, John; Becker, Antina Lübke; Deschner, Tobias; Wittig, Roman M; Lankester, Felix; Leendertz, Fabian H

2017-11-06

Habituation of wild great apes for tourism and research has had a significant positive effect on the conservation of these species. However, risks associated with such activities have been identified, specifically the transmission of human respiratory viruses to wild great apes, causing high morbidity and, occasionally, mortality. Here, we investigate the source of bacterial-viral co-infections in wild and captive chimpanzee communities in the course of several respiratory disease outbreaks. Molecular analyses showed that human respiratory syncytial viruses (HRSV) and human metapneumoviruses (HMPV) were involved in the etiology of the disease. In addition our analysis provide evidence for coinfection with Streptococcus (S.) pneumoniae. Characterisation of isolates from wild chimpanzees point towards a human origin of these bacteria. Transmission of these bacteria is of concern because - in contrast to HRSV and HMPV - S. pneumoniae can become part of the nasopharyngeal flora, contributing to the severity of respiratory disease progression. Furthermore these bacteria have the potential to spread to other individuals in the community and ultimately into the population. Targeted vaccination programs could be used to vaccinate habituated great apes but also human populations around great ape habitats, bringing health benefits to both humans and wild great apes.

Replication of type 5 adenovirus promotes middle ear infection by Streptococcus pneumoniae in the chinchilla model of otitis media

PubMed Central

Murrah, Kyle A.; Turner, Roberta L.; Pang, Bing; Perez, Antonia C.; Reimche, Jennifer L.; King, Lauren B.; Wren, John; Gandhi, Uma; Swords, W. Edward; Ornelles, David A.

2015-01-01

Adenoviral infection is a major risk factor for otitis media. We hypothesized that adenovirus promotes bacterial ascension into the middle ear through the disruption of normal function in the Eustachian tubes due to inflammation-induced changes. An intranasal infection model of the chinchilla was used to test the ability of type 5 adenovirus to promote middle ear infection by Streptococcus pneumoniae. The hyperinflammatory adenovirus mutant dl327 and the nonreplicating adenovirus mutant H5wt300ΔpTP were used to test the role of inflammation and viral replication, respectively, in promotion of pneumococcal middle ear infection. Precedent infection with adenovirus resulted in a significantly greater incidence of middle ear disease by S. pneumoniae as compared to nonadenovirus infected animals. Infection with the adenovirus mutant dl327 induced a comparable degree of bacterial ascension into the middle ear as did infection with the wild-type virus. By contrast, infection with the nonreplicating adenovirus mutant H5wt300ΔpTP resulted in less extensive middle ear infection compared to the wild-type adenovirus. We conclude that viral replication is necessary for adenoviral-induced pneumococcal middle ear disease. PMID:25251686

Role of teichoic acid choline moieties in the virulence of Streptococcus pneumoniae.

PubMed

Gehre, Florian; Spisek, Radek; Kharat, Arun S; Matthews, Phillip; Kukreja, Anjli; Anthony, Robert M; Dhodapkar, Madhav V; Vollmer, Waldemar; Tomasz, Alexander

2009-07-01

In recent reports it was shown that genetically modified choline-free strains of Streptococcus pneumoniae (D39Cho(-)licA64 and D39ChiplicB31) expressing the type II capsular polysaccharide were virtually avirulent in the murine sepsis model, in sharp contrast to the isogenic and highly virulent strains D39Cho(-) and D39Chip, which have retained the choline residues at their surface. We now demonstrate that this choline-associated virulence is independent of Toll-like receptor 2 recognition. Also, despite the lack of virulence, choline-free strains of S. pneumoniae were able to activate splenic dendritic cells, induce secretion of proinflammatory cytokines, and produce specific protective immunity against subsequent challenge. However, after this transient engagement of the immune system the choline-free bacteria were rapidly cleared from the blood, while the isogenic virulent strain D39Cho(-) continued to grow, accompanied by prolonged expression of cytokines, eventually killing the experimental animals. The critical contribution of choline residues to the virulence potential of pneumococci appears to be the role that these amino alcohol residues play in a pneumococcal immune evasion strategy, the mechanism of which is unknown at the present time.

Influence of impaired lipoprotein biogenesis on surface and exoproteome of Streptococcus pneumoniae.

PubMed

Pribyl, Thomas; Moche, Martin; Dreisbach, Annette; Bijlsma, Jetta J E; Saleh, Malek; Abdullah, Mohammed R; Hecker, Michael; van Dijl, Jan Maarten; Becher, Dörte; Hammerschmidt, Sven

2014-02-07

Surface proteins are important for the fitness and virulence of the Gram-positive pathogen Streptococcus pneumoniae. They are crucial for interaction of the pathogen with its human host during infection. Therefore, the analysis of the pneumococcal surface proteome is an important task that requires powerful tools. In this study, two different methods, an optimized biotinylation approach and shaving with trypsin beads, were applied to study the pneumococcal surface proteome and to identify surface-exposed protein domains, respectively. The identification of nearly 95% of the predicted lipoproteins and 75% of the predicted sortase substrates reflects the high coverage of the two classical surface protein classes accomplished in this study. Furthermore, the biotinylation approach was applied to study the impact of an impaired lipoprotein maturation pathway on the cell envelope proteome and exoproteome. Loss of the lipoprotein diacylglyceryl transferase Lgt leads to striking changes in the lipoprotein distribution. Many lipoproteins disappear from the surface proteome and accumulate in the exoproteome. Further insights into lipoprotein processing in pneumococci are provided by immunoblot analyses of bacterial lysates and corresponding supernatant fractions. Taken together, the first comprehensive overview of the pneumococcal surface and exoproteome is presented, and a model for lipoprotein processing in S. pneumoniae is proposed.

Streptococcus pneumoniae carriage among healthy and sick pediatric patients before the generalized implementation of the 13-valent pneumococcal vaccine in Morocco from 2010 to 2011.

PubMed

Jroundi, Imane; Mahraoui, Chafik; Benmessaoud, Rachid; Moraleda, Cinta; Munoz Almagro, Carmen; Seffar, Meryem; Tligui, Houssain; Kettani, Selma C; Benjelloun, Badr S; Alonso, Pedro L; Bassat, Quique

Nasopharyngeal carriage studies provide insights into the local prevalence of circulating pneumococcal serotypes. These data are critical to vaccination monitoring, as they allow for the prediction and assessment of impact. Very little data are available on the carriage of pneumococcal serotypes in Morocco. Here, we describe the prevalence of Streptococcus pneumoniae carriage and serotype distribution among 697 pediatric patients with ages ranging from 2 to 59 months who were admitted to a Moroccan hospital with severe pneumonia, as well as 195 healthy infants and young children who were recruited at a vaccination clinic. Carriage rates were 40.5% (79/195) for healthy children and 22.8% (159/697) for sick children. The most commonly observed circulating serotypes included 6A, 6B and 19F, all of which are included in the current 13-valent anti-pneumococcal conjugate vaccine that was recently introduced in Morocco. Monitoring of circulating serotypes remains necessary after vaccine introduction to assess whether serotype replacement is occurring. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Conformational analysis of the Streptococcus pneumoniae hyaluronate lyase and characterization of its hyaluronan-specific carbohydrate-binding module.

PubMed

Suits, Michael D L; Pluvinage, Benjamin; Law, Adrienne; Liu, Yan; Palma, Angelina S; Chai, Wengang; Feizi, Ten; Boraston, Alisdair B

2014-09-26

For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a β-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Streptococcus pneumoniae Can Utilize Multiple Sources of Hyaluronic Acid for Growth

PubMed Central

Marion, Carolyn; Stewart, Jason M.; Tazi, Mia F.; Burnaugh, Amanda M.; Linke, Caroline M.; Woodiga, Shireen A.

2012-01-01

The mechanisms by which Streptococcus pneumoniae obtains carbohydrates for growth during airway colonization remain to be elucidated. The low concentration of free carbohydrates in the normal human airway suggests that pneumococci must utilize complex glycan structures for growth. The glycosaminoglycan hyaluronic acid is present on the apical surface of airway epithelial cells. As pneumococci express a hyaluronate lyase (Hyl) that cleaves hyaluronic acid into disaccharides, we hypothesized that during colonization pneumococci utilize the released carbohydrates for growth. Hyaluronic acid supported significant pneumococcal growth in an hyl-dependent manner. A phosphoenolpyruvate-dependent phosphotransferase system (PTS) and an unsaturated glucuronyl hydrolase (Ugl) encoded downstream of hyl are also essential for growth on hyaluronic acid. This genomic arrangement is present in several other organisms, suggesting conservation of the utilization mechanism between species. In vivo experiments support the hypothesis that S. pneumoniae utilizes hyaluronic acid as a carbon source during colonization. We also demonstrate that pneumococci can utilize the hyaluronic acid capsule of other bacterial species for growth, suggesting an alternative carbohydrate source for pneumococcal growth. Together, these data support a novel function for pneumococcal degradation of hyaluronic acid in vivo and provide mechanistic details of growth on this glycosaminoglycan. PMID:22311922

Assessment of the susceptibility of Streptococcus pneumoniae to cefaclor and loracarbef in 13 countries.

PubMed

Bandak, S I; Turnak, M R; Allen, B S; Bolzon, L D; Preston, D A

2000-08-01

Between July 1998 and July 1999, 2,644 clinical isolates of Streptococcus pneumoniae were collected from 27 study centers in 13 countries and their susceptibilities to penicillin, cefaclor and loracarbef were determined by E-test" (AB BIODISK, Solna, Sweden). Overall, 96.3% of isolates were penicillin-susceptible (79.8%) or -intermediate (16.6%) (MIC, < or = 1 microg/ml). Rates of penicillin-resistant S. pneumoniae isolation varied widely and were highest in the study centers tested in New Zealand (10.9%), Canada (10.0%), Mexico (9.1%) and the United States (5.1%). Low rates of penicillin-resistance were found in the study centers tested in Russia (0%), Turkey (0%), Brazil (0.5%), Germany (0.6%), Philippines (1.6%), Italy (2.1%), United Kingdom (2.3%), Australia (3.0%) and Poland (3.1%). Using recently published NCCLS interpretative breakpoints (M100-S10, 2000), 87.2% (median) of all isolates tested were cefaclor-susceptible and 87.8% (median) of all isolates tested were loracarbef-susceptible. Of the penicillin-susceptible S. pneumoniae isolates, 99.5% were susceptible to both cefaclor and loracarbef. Susceptibility to cefaclor and loracarbef was also retained by 30.8% and 32.9% of penicillin-intermediate isolates, respectively. These findings are in contrast to recent publications reporting lower cefaclor and loracarbef activities using non-validated interpretative criteria. In conclusion, rates of penicillin resistance among recent clinical isolates of pneumococci remain low in many centers worldwide. Cefaclor and loracarbef demonstrated excellent in vitro activity against recent clinical isolates of penicillin-susceptible and many isolates of penicillin-intermediate S. pneumoniae.

Infection of zebrafish embryos with live fluorescent Streptococcus pneumoniae as a real-time pneumococcal meningitis model.

PubMed

Jim, Kin Ki; Engelen-Lee, JooYeon; van der Sar, Astrid M; Bitter, Wilbert; Brouwer, Matthijs C; van der Ende, Arie; Veening, Jan-Willem; van de Beek, Diederik; Vandenbroucke-Grauls, Christina M J E

2016-08-19

Streptococcus pneumoniae is one of the most important causes of bacterial meningitis, an infection where unfavourable outcome is driven by bacterial and host-derived toxins. In this study, we developed and characterized a pneumococcal meningitis model in zebrafish embryos that allows for real-time investigation of early host-microbe interaction. Zebrafish embryos were infected in the caudal vein or hindbrain ventricle with green fluorescent wild-type S. pneumoniae D39 or a pneumolysin-deficient mutant. The kdrl:mCherry transgenic zebrafish line was used to visualize the blood vessels, whereas phagocytic cells were visualized by staining with far red anti-L-plastin or in mpx:GFP/mpeg1:mCherry zebrafish, that have green fluorescent neutrophils and red fluorescent macrophages. Imaging was performed by fluorescence confocal and time-lapse microscopy. After infection by caudal vein, we saw focal clogging of the pneumococci in the blood vessels and migration of bacteria through the blood-brain barrier into the subarachnoid space and brain tissue. Infection with pneumolysin-deficient S. pneumoniae in the hindbrain ventricle showed attenuated growth and migration through the brain as compared to the wild-type strain. Time-lapse and confocal imaging revealed that the initial innate immune response to S. pneumoniae in the subarachnoid space mainly consisted of neutrophils and that pneumolysin-mediated cytolytic activity caused a marked reduction of phagocytes. This new meningitis model permits detailed analysis and visualization of host-microbe interaction in pneumococcal meningitis in real time and is a very promising tool to further our insights in the pathogenesis of pneumococcal meningitis.

Methylation of 23S rRNA Nucleotide G748 by RlmAII Methyltransferase Renders Streptococcus pneumoniae Telithromycin Susceptible

PubMed Central

Sato, Yoshiharu; Shoji, Tatsuma; Yamamoto, Tomoko

2013-01-01

Several posttranscriptional modifications of bacterial rRNAs are important in determining antibiotic resistance or sensitivity. In all Gram-positive bacteria, dimethylation of nucleotide A2058, located in domain V of 23S rRNA, by the dimethyltransferase Erm(B) results in low susceptibility and resistance to telithromycin (TEL). However, this is insufficient to produce high-level resistance to TEL in Streptococcus pneumoniae. Inactivation of the methyltransferase RlmAII, which methylates the N-1 position of nucleotide G748, located in hairpin 35 of domain II of 23S rRNA, results in increased resistance to TEL in erm(B)-carrying S. pneumoniae. Sixteen TEL-resistant mutants (MICs, 16 to 32 μg/ml) were obtained from a clinically isolated S. pneumoniae strain showing low TEL susceptibility (MIC, 2 μg/ml), with mutation resulting in constitutive dimethylation of A2058 because of nucleotide differences in the regulatory region of erm(B) mRNA. Primer extension analysis showed that the degree of methylation at G748 in all TEL-resistant mutants was significantly reduced by a mutation in the gene encoding RlmAII to create a stop codon or change an amino acid residue. Furthermore, RNA footprinting with dimethyl sulfate and a molecular modeling study suggested that methylation of G748 may contribute to the stable interaction of TEL with domain II of 23S rRNA, even after dimethylation of A2058 by Erm(B). This novel finding shows that methylation of G748 by RlmAII renders S. pneumoniae TEL susceptible. PMID:23716046

Methylation of 23S rRNA nucleotide G748 by RlmAII methyltransferase renders Streptococcus pneumoniae telithromycin susceptible.

PubMed

Takaya, Akiko; Sato, Yoshiharu; Shoji, Tatsuma; Yamamoto, Tomoko

2013-08-01

Several posttranscriptional modifications of bacterial rRNAs are important in determining antibiotic resistance or sensitivity. In all Gram-positive bacteria, dimethylation of nucleotide A2058, located in domain V of 23S rRNA, by the dimethyltransferase Erm(B) results in low susceptibility and resistance to telithromycin (TEL). However, this is insufficient to produce high-level resistance to TEL in Streptococcus pneumoniae. Inactivation of the methyltransferase RlmA(II), which methylates the N-1 position of nucleotide G748, located in hairpin 35 of domain II of 23S rRNA, results in increased resistance to TEL in erm(B)-carrying S. pneumoniae. Sixteen TEL-resistant mutants (MICs, 16 to 32 μg/ml) were obtained from a clinically isolated S. pneumoniae strain showing low TEL susceptibility (MIC, 2 μg/ml), with mutation resulting in constitutive dimethylation of A2058 because of nucleotide differences in the regulatory region of erm(B) mRNA. Primer extension analysis showed that the degree of methylation at G748 in all TEL-resistant mutants was significantly reduced by a mutation in the gene encoding RlmA(II) to create a stop codon or change an amino acid residue. Furthermore, RNA footprinting with dimethyl sulfate and a molecular modeling study suggested that methylation of G748 may contribute to the stable interaction of TEL with domain II of 23S rRNA, even after dimethylation of A2058 by Erm(B). This novel finding shows that methylation of G748 by RlmA(II) renders S. pneumoniae TEL susceptible.

Macrolones Are a Novel Class of Macrolide Antibiotics Active against Key Resistant Respiratory Pathogens In Vitro and In Vivo.

PubMed

Čipčić Paljetak, Hana; Verbanac, Donatella; Padovan, Jasna; Dominis-Kramarić, Miroslava; Kelnerić, Željko; Perić, Mihaela; Banjanac, Mihailo; Ergović, Gabrijela; Simon, Nerrisa; Broskey, John; Holmes, David J; Eraković Haber, Vesna

2016-09-01

As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Identification of novel non-coding small RNAs from Streptococcus pneumoniae TIGR4 using high-resolution genome tiling arrays

PubMed Central

2010-01-01

Background The identification of non-coding transcripts in human, mouse, and Escherichia coli has revealed their widespread occurrence and functional importance in both eukaryotic and prokaryotic life. In prokaryotes, studies have shown that non-coding transcripts participate in a broad range of cellular functions like gene regulation, stress and virulence. However, very little is known about non-coding transcripts in Streptococcus pneumoniae (pneumococcus), an obligate human respiratory pathogen responsible for significant worldwide morbidity and mortality. Tiling microarrays enable genome wide mRNA profiling as well as identification of novel transcripts at a high-resolution. Results Here, we describe a high-resolution transcription map of the S. pneumoniae clinical isolate TIGR4 using genomic tiling arrays. Our results indicate that approximately 66% of the genome is expressed under our experimental conditions. We identified a total of 50 non-coding small RNAs (sRNAs) from the intergenic regions, of which 36 had no predicted function. Half of the identified sRNA sequences were found to be unique to S. pneumoniae genome. We identified eight overrepresented sequence motifs among sRNA sequences that correspond to sRNAs in different functional categories. Tiling arrays also identified approximately 202 operon structures in the genome. Conclusions In summary, the pneumococcal operon structures and novel sRNAs identified in this study enhance our understanding of the complexity and extent of the pneumococcal 'expressed' genome. Furthermore, the results of this study open up new avenues of research for understanding the complex RNA regulatory network governing S. pneumoniae physiology and virulence. PMID:20525227

Association between nasopharyngeal load of Streptococcus pneumoniae, viral coinfection, and radiologically confirmed pneumonia in Vietnamese children.

PubMed

Vu, Huong Thi Thu; Yoshida, Lay Myint; Suzuki, Motoi; Nguyen, Hien Anh Thi; Nguyen, Cat Dinh Lien; Nguyen, Ai Thi Thuy; Oishi, Kengo; Yamamoto, Takeshi; Watanabe, Kiwao; Vu, Thiem Dinh

2011-01-01

The interplay between nasopharyngeal bacterial carriage, viral coinfection, and lower respiratory tract infections (LRTIs) is poorly understood. We explored this association in Vietnamese children aged less than 5 years. A hospital-based case-control study of pediatric LRTIs was conducted in Nha Trang, Vietnam. A total of 550 hospitalized children (274 radiologically confirmed pneumonia [RCP] and 276 other LRTIs) were enrolled and 350 healthy controls were randomly selected from the community. Polymerase chain reaction-based methods were used to measure bacterial loads of Streptococcus pneumoniae (SP), Haemophilus influenzae, and Moraxella catarrhalis and to detect 13 respiratory viruses and bacterial serotypes in nasopharyngeal samples of study participants. The median nasopharyngeal bacterial load of SP was substantially higher in children with RCP compared with healthy controls or children with other LRTIs (P < 0.001). SP load was 15-fold higher in pneumonia children with viral coinfection compared with those children without viral coinfection (1.4 x 10⁷/mL vs. 9.1 x 10⁵/mL; P 0.0001). SP load was over 200-fold higher in serotypeable SP compared with nontypeable SP (2.5 x 10⁶/mL vs. 1 x 10⁴/mL; P < 0.0001). These associations were independent of potential confounders in multiple regression models. No clear association was found between nasopharyngeal load of Haemophilus influenzae or Moraxella catarrhalis and viral coinfection in either RCP or other LRTIs groups. An increased load of SP in the nasopharynx was associated with RCP, viral coinfection, and presence of pneumococcal capsule.

[Paediatric Invasive Pneumococcal Disease Before Universal Vaccination: 1995 - 2015].

PubMed

Ferreira, Muriel; Oliveira, Henrique; Silva, Nuno Costa; Januário, Luís; Rodrigues, Fernanda

2017-06-30

Pneumococcal conjugate vaccine was introduced in the private market in Portugal in 2001, reaching over the years a moderately high coverage. In July 2015, it was included in the National Immunisation Program. The aim of this study was to characterize invasive pneumococcal disease in a pediatric hospital before universal use of the vaccine. Retrospective analysis of medical records of all children with Streptococcus pneumoniae identified by culture and/or molecular biology (available since 2008), in products obtained from sterile sites, from January 1995 to June 2015. We evaluated demographic, clinical and microbiological data. Serotype results are available since 2004. Over those 20 years, 112 invasive pneumococcal disease cases were identified, with a median age of 15 months (1 month - 15 years). The median number of cases /year was 4, the highest between 2001 - 2002 (8/year) and 2007 - 2012 (7 - 11/year). The identification occurred mostly in blood culture (72), cerebrospinal fluid (24), pleural fluid (11) an others (5). The most frequent diagnoses were pneumonia (38%), occult bacteraemia (34%) and meningitis (21%). Over the period under review, there was an increase of pneumonia and slight increase of OB, with meningitis cases remaining relatively unchanged. In the last two decades, there was no reduction in the number of cases of invasive pneumococcal disease. There was an increase in isolates from pneumonia and occult bacteraemia that might be due to the introduction of molecular biological methods for Streptococcus pneumoniae detection. Vaccine serotypes were predominant. This retrospective analysis before universal vaccination will contribute to evaluate the impact of vaccination in the Portuguese pediatric population.

Sequence Elements Upstream of the Core Promoter Are Necessary for Full Transcription of the Capsule Gene Operon in Streptococcus pneumoniae Strain D39

PubMed Central

Wen, Zhensong; Sertil, Odeniel; Cheng, Yongxin; Zhang, Shanshan; Liu, Xue; Wang, Wen-Ching

2015-01-01

Streptococcus pneumoniae is a major bacterial pathogen in humans. Its polysaccharide capsule is a key virulence factor that promotes bacterial evasion of human phagocytic killing. While S. pneumoniae produces at least 94 antigenically different types of capsule, the genes for biosynthesis of almost all capsular types are arranged in the same locus. The transcription of the capsular polysaccharide (cps) locus is not well understood. This study determined the transcriptional features of the cps locus in the type 2 virulent strain D39. The initial analysis revealed that the cps genes are cotranscribed from a major transcription start site at the −25 nucleotide (G) upstream of cps2A, the first gene in the locus. Using unmarked chromosomal truncations and a luciferase-based transcriptional reporter, we showed that the full transcription of the cps genes not only depends on the core promoter immediately upstream of cps2A, but also requires additional elements upstream of the core promoter, particularly a 59-bp sequence immediately upstream of the core promoter. Unmarked deletions of these promoter elements in the D39 genome also led to significant reduction in CPS production and virulence in mice. Lastly, common cps gene (cps2ABCD) mutants did not show significant abnormality in cps transcription, although they produced significantly less CPS, indicating that the CpsABCD proteins are involved in the encapsulation of S. pneumoniae in a posttranscriptional manner. This study has yielded important information on the transcriptional characteristics of the cps locus in S. pneumoniae. PMID:25733517

Distribution of capsular types and antimicrobial susceptibility of invasive isolates of Streptococcus pneumoniae in Colombian children. Pneumococcal Study Group in Colombia.

PubMed

Castañeda, E; Leal, A L; Castillo, O; De La Hoz, F; Vela, M C; Arango, M; Trujillo, H; Levy, A; Gama, M E; Calle, M; Valencia, M L; Parra, W; Agudelo, N; Mejía, G I; Jaramillo, S; Montoya, F; Porras, H; Sánchez, A; Saa, D; Di Fabio, J L; Homma, A

1997-01-01

Streptococcus pneumoniae is the leading bacterial cause of childhood pneumonia in the developing world. This study describes the type distribution and antimicrobial susceptibility of invasive pneumococcal isolates from Colombian children and is part of the Sistema Regional de Vacunas (SIREVA), a PAHO regional initiative designed to determine the ideal serotype composition of a protein polysaccharide pneumococcal conjugate vaccine for use in children less than 5 years old in Latin America. In Colombia, during the study period, centres in Bogota, Medellin, and Cali collected 324 S. pneumoniae isolates from invasive diseases, 238 (73.5%) from children under the age of 2. Pneumonia was the clinical diagnosis in 41.3% cases, meningitis in 41%, and sepsis in 11.2%. The seven most frequent types included 14(21.9%), 5(10.5%), 23F(9.6%), 1(9%), 6B(9%), 19F(7.1%), and 6A(6.2%). The frequency of diminished susceptibility to penicillin (DSP) was 12%, with 8.9% of isolates showing intermediate level resistance and 3.1% showing high level resistance. Among DSP isolates, 23% were also resistant to cefotaxime, 33.3% to erythromycin, 48.7% to chloramphenicol, and 74.3% to trimethoprim/sulfamethoxazole. Multiple resistance was detected in 59% of the isolates that have DSP. Penicillin resistance was associated with types 23F (53.8%) and 14 (25.6%). These data provides information on capsular types prevalent in Colombia that will not only allow the formulation of an ideal vaccine for the region but also reinforce the need for ongoing regional surveillance.

Macrolones Are a Novel Class of Macrolide Antibiotics Active against Key Resistant Respiratory Pathogens In Vitro and In Vivo

PubMed Central

Verbanac, Donatella; Padovan, Jasna; Dominis-Kramarić, Miroslava; Kelnerić, Željko; Perić, Mihaela; Banjanac, Mihailo; Ergović, Gabrijela; Simon, Nerrisa; Broskey, John; Holmes, David J.; Eraković Haber, Vesna

2016-01-01

As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo. MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy. PMID:27353268

A Comprehensive Genetic Study of Streptococcal Immunoglobulin A1 Proteases: Evidence for Recombination within and between Species

PubMed Central

Poulsen, Knud; Reinholdt, Jesper; Jespersgaard, Christina; Boye, Kit; Brown, Thomas A.; Hauge, Majbritt; Kilian, Mogens

1998-01-01

An analysis of 13 immunoglobulin A1 (IgA1) protease genes (iga) of strains of Streptococcus pneumoniae, Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguis was carried out to obtain information on the structure, polymorphism, and phylogeny of this specific protease, which enables bacteria to evade functions of the predominant Ig isotype on mucosal surfaces. The analysis included cloning and sequencing of iga genes from S. oralis and S. mitis biovar 1, sequencing of an additional seven iga genes from S. sanguis biovars 1 through 4, and restriction fragment length polymorphism (RFLP) analyses of iga genes of another 10 strains of S. mitis biovar 1 and 6 strains of S. oralis. All 13 genes sequenced had the potential of encoding proteins with molecular masses of approximately 200 kDa containing the sequence motif HEMTH and an E residue 20 amino acids downstream, which are characteristic of Zn metalloproteinases. In addition, all had a typical gram-positive cell wall anchor motif, LPNTG, which, in contrast to such motifs in other known streptococcal and staphylococcal proteins, was located in their N-terminal parts. Repeat structures showing variation in number and sequence were present in all strains and may be of relevance to the immunogenicities of the enzymes. Protease activities in cultures of the streptococcal strains were associated with species of different molecular masses ranging from 130 to 200 kDa, suggesting posttranslational processing possibly as a result of autoproteolysis at post-proline peptide bonds in the N-terminal parts of the molecules. Comparison of deduced amino acid sequences revealed a 94% similarity between S. oralis and S. mitis IgA1 proteases and a 75 to 79% similarity between IgA1 proteases of these species and those of S. pneumoniae and S. sanguis, respectively. Combined with the results of RFLP analyses using different iga gene fragments as probes, the results of nucleotide sequence comparisons provide evidence of horizontal transfer of iga gene sequences among individual strains of S. sanguis as well as among S. mitis and the two species S. pneumoniae and S. oralis. While iga genes of S. sanguis and S. oralis were highly homogeneous, the genes of S. pneumoniae and S. mitis showed extensive polymorphism reflected in different degrees of antigenic diversity. PMID:9423856

Non-typeable Haemophilus influenzae and Streptococcus pneumoniae as primary causes of acute otitis media in colombian children: a prospective study

PubMed Central

2011-01-01

Background Acute otitis media (AOM) is one of the most frequently encountered bacterial infections in children aged < 5 years; Streptococcus pneumoniae (S. pneumoniae) and non-typeable Haemophilus influenzae (NTHi) are historically identified as primary AOM causes. Nevertheless, recent data on bacterial pathogens causing AOM in Latin America are limited. This prospective study aimed to identify and characterize bacterial etiology and serotypes of AOM cases including antimicrobial susceptibility in < 5 year old Colombian children. Methods From February 2008 to January 2009, children ≥3 months and < 5 years of age presenting with AOM and for whom a middle ear fluid (MEF) sample was available were enrolled in two medical centers in Cali, Colombia. MEF samples were collected either by tympanocentesis procedure or spontaneous otorrhea swab sampling. Bacteria were identified using standard laboratory methods, and antimicrobial resistance testing was performed based on the 2009 Clinical and Laboratory Standards Institute (CLSI) criteria. Most of the cases included in the study were sporadic in nature. Results Of the 106 enrolled children, 99 were included in the analysis. Bacteria were cultured from 62/99 (63%) of samples with S. pneumoniae, H. influenzae, or S. pyogenes. The most commonly isolated bacteria were H. influenzae in 31/99 (31%) and S. pneumoniae in 30/99 (30%) of samples. The majority of H. influenzae episodes were NTHi (27/31; 87%). 19F was the most frequently isolated pneumococcal serotype (10/30; 33%). Of the 30 S. pneumoniae positive samples, 8/30 (27%) were resistant to tetracycline, 5/30 (17%) to erythromycin and 8/30 (27%) had intermediate resistance to penicillin. All H. influenzae isolates tested were negative to beta-lactamase. Conclusions NTHi and S. pneumoniae are the leading causes of AOM in Colombian children. A pneumococcal conjugate vaccine that prevents both pathogens could be useful in maximizing protection against AOM. PMID:21208431

Community-Acquired Pneumonia in the Asia-Pacific Region.

PubMed

Song, Jae-Hoon; Huh, Kyungmin; Chung, Doo Ryeon

2016-12-01

Community-acquired pneumonia (CAP) is an important cause of mortality and morbidity worldwide. Aging population, dense urbanization, and poor access to health care make the Asia-Pacific region vulnerable to CAP. The high incidence of CAP poses a significant health and economic burden in this region. Common etiologic agents in other global regions including Streptococcus pneumoniae , Mycoplasma pneumoniae , Haemophilus influenzae , Chlamydophila pneumoniae , Staphylococcus aureus , and respiratory viruses are also the most prevalent pathogens in the Asia-Pacific region. But the higher incidence of Klebsiella pneumoniae and the presence of Burkholderia pseudomallei are unique to the region. The high prevalence of antimicrobial resistance in S. pneumoniae and M. pneumoniae has been raising the need for more prudent use of antibiotics. Emergence and spread of community-acquired methicillin-resistant S. aureus deserve attention, while the risk has not reached significant level yet in cases of CAP. Given a clinical and socioeconomic importance of CAP, further effort to better understand the epidemiology and impact of CAP is warranted in the Asia-Pacific region. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Clinical scoring system in the evaluation of adult pharyngitis.

PubMed

Seppälä, H; Lahtonen, R; Ziegler, T; Meurman, O; Hakkarainen, K; Miettinen, A; Arstila, P; Eskola, J; Saikku, P; Huovinen, P

1993-03-01

To compare results of a clinical scoring system for diagnosis of group A streptococcal pharyngitis with microbiologic results, when several different pharyngeal pathogens were tested simultaneously. Evaluation of clinical manifestations of 106 adult patients with pharyngitis of different microbial origin. General private practice; Health Center Pulssi, Turku, Finland. Adult patients whose chief complaints were sore throats. A symptom score that was assigned to each patient according to the total number of certain signs and symptoms that are postulated to increase the probability of group A streptococcal pharyngitis and blood measurements for infection. The highest symptom scores, 3 and 4, were found in 21 patients. These patients had pharyngitis due to group A streptococcus (four patients), group C streptococcus (four patients), group G streptococcus (two patients), group F streptococcus, Mycoplasma pneumoniae, Chlamydia pneumoniae, influenza A virus, influenza B virus, herpes simplex type 1 virus (two patients), and coxsackie B4 virus. No pathogen could be identified from three of the 21 patients. The C-reactive protein values and the leukocyte counts were raised significantly more often in streptococcal infections than in infections of other origin; the P values were .00016 and .028, respectively. Use of a clinical scoring system alone for diagnosis of pharyngitis may lead to improper use of anti-microbial agents. There is a need for accurate microbiologic diagnostic procedures in general practice to determine proper treatment of pharyngitis as well as to test the effect of antibacterial and, in the future, antiviral treatment in respiratory tract infections.

Antimicrobial properties of the stem bark of Saraca indica (Caesalpiniaceae).

PubMed

Sainath, R Shilpakala; Prathiba, J; Malathi, R

2009-01-01

Chloroform, methanol, aqueous and ethanolic extracts of the stem bark of Saraca indica were investigated for their antibacterial and antifungal activity against standard strains of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Klebsiella pneumoniae, Proteus mirabilis, Salmonella typhimurium and Streptococcus pneumoniae and the fungi: Candida albicans and Cryptococcus albidus. Methanolic and aqueous extract exhibited antimicrobial activity with MIC ranging from 0.5-2% and 1-3% respectively. Methanolic extract exhibited the strongest activity against both bacteria and fungi.

[In vitro and in vivo antibacterial activities of sulopenem, a new penem antibiotic].

PubMed

Komoto, A; Otsuki, M; Nishino, T

1996-04-01

The in vitro and in vivo antibacterial activities of sulopenem, a new penem, were evaluated in comparison with imipenem (IPM), meropenem (MEPM), ceftazidime (CAZ) and flomoxef (FMOX). Sulopenem had broad and potent antibacterial spectra against Gram-positive and Gram-negative bacteria, including Enterococcus faecalis, Proteus vulgaris, Morganella morganii, Enterobacter spp. and Citrobacter freundii. Sulopenem showed concentration-dependent bactericidal activities against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Acinetobacter calcoaceticus. Morphological observation using phase-contrast microscope revealed that sulopenem induced spherical cell formation with E. coli and K. pneumoniae at lower concentrations and bacteriolysis at higher concentrations. Therapeutic efficacies of sulopenem against systemic infections in mice were almost equal to those of imipenem against Streptococcus pneumoniae. While its therapeutic efficacies were superior to those of meropenem, ceftazidime and flomoxef against S. aureus and S. pneumoniae, they were inferior to those of imipenem/cilastatin against S. aureus, K. pneumoniae and A. calcoaceticus.

[Characteristics of community-acquired pneumonia in servicemen during the military conflict on the Northern Caucasus in 1995-1996].

PubMed

Rakov, A L; Komarevtsev, V N; Kharitonov, M A; Kazantsev, V A

2005-07-01

The data of the examination and treatment of 1150 sick servicemen in different conditions of service in Republic of Chechnya in the military conflict in 1995-1996 are investigated. It was found out that the principal somatic pathology in the structure of sanitary losses of servicemen in the military conflict was respiratory organ diseases, mainly pneumonia, whose etiology as a rule does not depend on the character of the military-and-professional activities and places of troops' distribution. The chief role in the etiology of pneumonia was played by Streptococcus pneumoniae (43.4%). The peculiarities of the clinical picture of pneumoniaduring fighting are stipulated by chronic adaptation overstrain syndrome. Traditional schemes of treatment for such pneumonia do not ensure recovery of the sick within the usual period and do not prevent the development of various complications.

Population structure of Streptococcus oralis

PubMed Central

Do, Thuy; Jolley, Keith A.; Maiden, Martin C. J.; Gilbert, Steven C.; Clark, Douglas; Wade, William G.; Beighton, David

2009-01-01

Streptococcus oralis is a member of the normal human oral microbiota, capable of opportunistic pathogenicity; like related oral streptococci, it exhibits appreciable phenotypic and genetic variation. A multilocus sequence typing (MLST) scheme for S. oralis was developed and the resultant data analysed to examine the population structure of the species. Analysis of 113 isolates, confirmed as belonging to the S. oralis/mitis group by 16S rRNA gene sequencing, characterized the population as highly diverse and undergoing inter- and intra-species recombination with a probable clonal complex structure. ClonalFrame analysis of these S. oralis isolates along with examples of Streptococcus pneumoniae, Streptococcus mitis and Streptococcus pseudopneumoniae grouped the named species into distinct, coherent populations and did not support the clustering of S. pseudopneumoniae with S. mitis as reported previously using distance-based methods. Analysis of the individual loci suggested that this discrepancy was due to the possible hybrid nature of S. pseudopneumoniae. The data are available on the public MLST website (http://pubmlst.org/soralis/). PMID:19423627

Identification of Enterococcus, Streptococcus, and Staphylococcus by Multivariate Analysis of Proton Magnetic Resonance Spectroscopic Data from Plate Cultures

PubMed Central

Bourne, Roger; Himmelreich, Uwe; Sharma, Ansuiya; Mountford, Carolyn; Sorrell, Tania

2001-01-01

A new fingerprinting technique with the potential for rapid identification of bacteria was developed by combining proton magnetic resonance spectroscopy (1H MRS) with multivariate statistical analysis. This resulted in an objective identification strategy for common clinical isolates belonging to the bacterial species Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus agalactiae, and the Streptococcus milleri group. Duplicate cultures of 104 different isolates were examined one or more times using 1H MRS. A total of 312 cultures were examined. An optimized classifier was developed using a bootstrapping process and a seven-group linear discriminant analysis to provide objective classification of the spectra. Identification of isolates was based on consistent high-probability classification of spectra from duplicate cultures and achieved 92% agreement with conventional methods of identification. Fewer than 1% of isolates were identified incorrectly. Identification of the remaining 7% of isolates was defined as indeterminate. PMID:11474013

67 FR 64386 - Enhancement of Surveillance for Trimethoprim-Sulfamethoxazole Resistant Invasive Respiratory and...

Federal Register 2010, 2011, 2012, 2013, 2014

2002-10-18

... cerebrospinal fluid infections caused by key Pathogens-Streptococcus Pneumoniae, Haemophilus Influenzae, and non... pathogens causing meningitis (pneumococcus, Haemophilus Influenzae, and Meningococcus). The infrastructure... testing, for meningitis agents including pneumococcus and Haemophilus Influenzae. Laboratory staff have...

Child pneumonia - focus on the Western Pacific Region.

PubMed

Nguyen, T K P; Tran, T H; Roberts, C L; Graham, S M; Marais, B J

2017-01-01

Worldwide, pneumonia is the leading cause of death in infants and young children (aged <5 years). We provide an overview of the global pneumonia disease burden, as well as the aetiology and management practices in different parts of the world, with a specific focus on the WHO Western Pacific Region. In 2011, the Western Pacific region had an estimated 0.11 pneumonia episodes per child-year with 61,900 pneumonia-related deaths in children less than 5 years of age. The majority (>75%) of pneumonia deaths occurred in six countries; Cambodia, China, Laos, Papua New Guinea, the Philippines and Viet Nam. Historically Streptococcus pneumoniae and Haemophilus influenzae were the commonest causes of severe pneumonia and pneumonia-related deaths in young children, but this is changing with the introduction of highly effective conjugate vaccines and socio-economic development. The relative contribution of viruses and atypical bacteria appear to be increasing and traditional case management approaches may require revision to accommodate increased uptake of conjugated vaccines in the Western Pacific region. Careful consideration should be given to risk reduction strategies, enhanced vaccination coverage, improved management of hypoxaemia and antibiotic stewardship. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecular Detection of Streptococcus pneumoniae on Dried Blood Spots from Febrile Nigerian Children Compared to Culture

PubMed Central

Iroh Tam, Pui-Ying; Hernandez-Alvarado, Nelmary; Schleiss, Mark R.; Hassan-Hanga, Fatimah; Onuchukwu, Chuma; Umoru, Dominic; Obaro, Stephen K.

2016-01-01

Background Nigeria has one of the highest burdens of pneumococcal disease in the world, but accurate surveillance is lacking. Molecular detection of infectious pathogens in dried blood spots (DBS) is an ideal method for surveillance of infections in resource-limited settings because of its low cost, minimal blood volumes involved, and ease of storage at ambient temperature. Our study aim was to evaluate a Streptococcus pneumoniae real-time polymerase chain reaction (rt-PCR) assay on DBS from febrile Nigerian children on Whatman 903 and FTA filter papers, compared to the gold standard of culture. Methods Between September 2011 to May 2015, blood was collected from children 5 years of age or under who presented to six hospital study sites throughout northern and central Nigeria with febrile illness, and inoculated into blood culture bottles or spotted onto Whatman 903 or FTA filter paper. Culture and rt-PCR were performed on all samples. Results A total of 537 DBS specimens from 535 children were included in the study, of which 15 were culture-positive for S. pneumoniae. The rt-PCR assay detected S. pneumoniae in 12 DBS specimens (2.2%). One positive rt-PCR result was identified in a culture-negative specimen from a high-risk subject, and two positive rt-PCR results were negative on repeat testing. Six culture-confirmed cases of S. pneumoniae bacteremia were missed. Compared to culture, the overall sensitivities of Whatman 903 and FTA DBS for detection of S. pneumoniae were 57.1% (95% CI 18.4–90.1%) and 62.5% (95% CI 24.5–91.5%), respectively. Nonspecific amplification was noted in an additional 22 DBS (4.1%). Among these, six were positive for a non-S. pneumoniae pathogen on culture. Conclusions Rt-PCR was able to detect S. pneumoniae from clinical DBS specimens, including from a culture-negative specimen. Our findings show promise of this approach as a surveillance diagnostic, but also raise important cautionary questions. Several DBS specimens were detected as S. pneumoniae by rt-PCR despite growth of a non-S. pneumoniae pathogen on culture. A precise definition of what constitutes a positive result is required to avoid falsely over-identifying specimens. PMID:27007889

Prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae in China: a meta-analysis.

PubMed

Wang, Lin; Fu, Jinjian; Liang, Zhuoxin; Chen, Jichang

2017-12-13

To explore the overall prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae(S. pneumoniae) among healthy children. A search for pneumococcal nasopharyngeal carriage studies including children published up to July 31th, 2016 was conducted to describe carriage in China. The review also describes antibiotic resistance in and serotypes of S. pneumoniae and assesses the impact of vaccination on carriage in this region. Summary measures for overall prevalence, antibiotic resistance, and serotype distributions extracted from the analyzed data were determined with 95% confidence intervals (CIs) using random-effects models. Heterogeneity was assessed using I 2 test statistics. Thirty-seven studies were included in this review, and the majority of studies (64.9%) were located in the pre-introduction period of 7-valent pneumococcal conjugate vaccine (PCV7) in China. The pooled prevalence of S. pneumoniae nasopharyngeal carriage was 21.4% (95% CI: 18.3-24.4%). Carriage was highest in children attending kindergartens [24.5%, (19.7-29.3%)] and decreased with increasing age. Before the introduction of PCV7 into China, the prevalence of S. pneumoniae nasopharyngeal carriage was 25.8% (20.7-30.9%), the pooled carriage of S. pneumoniae sharply dropped into the 14.1% (11.3-16.9%) by PCV7 vaccination period (P < 0.001). Before the pneumococcal conjugate vaccine (PCV) was introduced in China, the penicillin resistance rate in S. pneumoniae isolated from healthy children was 31.9% (21.2-42.6%); however, this rate sharply decreased after the introduction of PCV7 in China [21.6%, (7.4-35.9%)], and the difference between the rates during these two time periods was statistically significant (P value <0.05). Serotypes 19F, 6A and 23F were the most commonly isolated. Meta-analysis of data from young children showed a pooled rate estimate of 46.6% (38.8-54.4%) for PCV7 vaccine coverage and 66.2% (58.6-73.8%) for PCV13 vaccine coverage. The prevalence of nasopharyngeal carriage among children was high in China. PCV7 immunization was found to be associated with reduction of nasopharyngeal colonization of S. pneumoniae. Conjugate vaccination coverage was slightly affected by the introduction of PCV7 into China because of low vaccination rate. The government should implement timely adjusted conjugate vaccination strategies based on our findings.

Structural and Functional Analysis of Cell Wall-anchored Polypeptide Adhesin BspA in Streptococcus agalactiae*

PubMed Central

Rego, Sara; Heal, Timothy J.; Pidwill, Grace R.; Till, Marisa; Robson, Alice; Lamont, Richard J.; Sessions, Richard B.; Jenkinson, Howard F.; Race, Paul R.; Nobbs, Angela H.

2016-01-01

Streptococcus agalactiae (group B Streptococcus, GBS) is the predominant cause of early-onset infectious disease in neonates and is responsible for life-threatening infections in elderly and immunocompromised individuals. Clinical manifestations of GBS infection include sepsis, pneumonia, and meningitis. Here, we describe BspA, a deviant antigen I/II family polypeptide that confers adhesive properties linked to pathogenesis in GBS. Heterologous expression of BspA on the surface of the non-adherent bacterium Lactococcus lactis confers adherence to scavenger receptor gp340, human vaginal epithelium, and to the fungus Candida albicans. Complementary crystallographic and biophysical characterization of BspA reveal a novel β-sandwich adhesion domain and unique asparagine-dependent super-helical stalk. Collectively, these findings establish a new bacterial adhesin structure that has in effect been hijacked by a pathogenic Streptococcus species to provide competitive advantage in human mucosal infections. PMID:27311712

Cationic Antimicrobial Peptide Resistance Mechanisms of Streptococcal Pathogens

PubMed Central

LaRock, Christopher N.; Nizet, Victor

2015-01-01

Cationic antimicrobial peptides (CAMPs) are critical front line contributors to host defense against invasive bacterial infection. These immune factors have direct killing activity toward microbes, but many pathogens are able to resist their effects. Group A Streptococcus, group B Streptococcus and Streptococcus pneumoniae are among the most common pathogens of humans and display a variety of phenotypic adaptations to resist CAMPs. Common themes of CAMP resistance mechanisms among the pathogenic streptococci are repulsion, sequestration, export, and destruction. Each pathogen has a different array of CAMP-resistant mechanisms, with invasive disease potential reflecting the utilization of several mechanisms that may act in synergy. Here we discuss recent progress in identifying the sources of CAMP resistance in the medically important Streptococcus genus. Further study of these mechanisms can contribute to our understanding of streptococcal pathogenesis, and may provide new therapeutic targets for therapy and disease prevention. PMID:25701232

Genome-wide essential gene identification in Streptococcus sanguinis

PubMed Central

Xu, Ping; Ge, Xiuchun; Chen, Lei; Wang, Xiaojing; Dou, Yuetan; Xu, Jerry Z.; Patel, Jenishkumar R.; Stone, Victoria; Trinh, My; Evans, Karra; Kitten, Todd; Bonchev, Danail; Buck, Gregory A.

2011-01-01

A clear perception of gene essentiality in bacterial pathogens is pivotal for identifying drug targets to combat emergence of new pathogens and antibiotic-resistant bacteria, for synthetic biology, and for understanding the origins of life. We have constructed a comprehensive set of deletion mutants and systematically identified a clearly defined set of essential genes for Streptococcus sanguinis. Our results were confirmed by growing S. sanguinis in minimal medium and by double-knockout of paralogous or isozyme genes. Careful examination revealed that these essential genes were associated with only three basic categories of biological functions: maintenance of the cell envelope, energy production, and processing of genetic information. Our finding was subsequently validated in two other pathogenic streptococcal species, Streptococcus pneumoniae and Streptococcus mutans and in two other gram-positive pathogens, Bacillus subtilis and Staphylococcus aureus. Our analysis has thus led to a simplified model that permits reliable prediction of gene essentiality. PMID:22355642

The role of respiratory viruses in the etiology of bacterial pneumonia

PubMed Central

Lee, Kyu Han; Gordon, Aubree; Foxman, Betsy

2016-01-01

Pneumonia is the leading cause of death among children less than 5 years old worldwide. A wide range of viral, bacterial and fungal agents can cause pneumonia: although viruses are the most common etiologic agent, the severity of clinical symptoms associated with bacterial pneumonia and increasing antibiotic resistance makes bacterial pneumonia a major public health concern. Bacterial pneumonia can follow upper respiratory viral infection and complicate lower respiratory viral infection. Secondary bacterial pneumonia is a major cause of influenza-related deaths. In this review, we evaluate the following hypotheses: (i) respiratory viruses influence the etiology of pneumonia by altering bacterial community structure in the upper respiratory tract (URT) and (ii) respiratory viruses promote or inhibit colonization of the lower respiratory tract (LRT) by certain bacterial species residing in the URT. We conducted a systematic review of the literature to examine temporal associations between respiratory viruses and bacteria and a targeted review to identify potential mechanisms of interactions. We conclude that viruses both alter the bacterial community in the URT and promote bacterial colonization of the LRT. However, it is uncertain whether changes in the URT bacterial community play a substantial role in pneumonia etiology. The exception is Streptococcus pneumoniae where a strong link between viral co-infection, increased carriage and pneumococcal pneumonia has been established. PMID:26884414

An outbreak of pneumonia associated with S. pneumoniae at a military training facility in Finland in 2006.

PubMed

Vainio, Anni; Lyytikäinen, Outi; Sihvonen, Reetta; Kaijalainen, Tarja; Teirilä, Laura; Rantala, Merja; Lehtinen, Pirkko; Ruuska, Pekka; Virolainen, Anni

2009-07-01

Streptococcus pneumoniae is a well-known cause of community-acquired bacterial pneumonia. The purpose of this study was to assess the cause and extent of the outbreak of pneumonia which occurred among military recruits following a 1-week hard encampment in Finland. We also assessed the carriage rate and molecular characteristics of the S. pneumoniae isolates. All pneumococcal isolates were studied for antibiotic susceptibility, serotyped, genotyped by multilocus sequence typing (MLST), and the presence of pneumococcal rlrA pilus islet was detected. The genotype results defined by MLST corresponded with the serotype results. S. pneumoniae serotype 7F, ST2331, seemed to be associated with an outbreak of pneumonia and nasopharyngeal carriage among 43 military recruits. Of the 43 military recruits, five (12%) were hospitalized with pneumonia and two (40%) of them were positive for S. pneumoniae serotype 7F, ST2331 by blood culture. Eighteen (42%) of the 43 men were found to be positive for S. pneumoniae by nasopharyngeal culture, and nine (50%) of them carried pneumococcal serotype 7F, ST2331. The outbreak strain covered 55% of all the pneumococcal findings. Outbreaks of invasive pneumococcal disease seem to occur in a crowded environment such as a military training facility even among previously healthy young men.

Genetic diversity of Streptococcus equi subsp. zooepidemicus and doxycycline resistance in kennelled dogs.

PubMed

Chalker, Victoria J; Waller, Andrew; Webb, Katy; Spearing, Emma; Crosse, Patricia; Brownlie, Joe; Erles, Kerstin

2012-06-01

The genetic diversity and antibiotic resistance profiles of 38 Streptococcus equi subsp. zooepidemicus isolates were determined from a kennelled canine population during two outbreaks of hemorrhagic pneumonia (1999 to 2002 and 2007 to 2010). Analysis of the szp gene hypervariable region and the 16S-23S rRNA intergenic spacer region and multilocus sequence typing (MLST) indicated a predominant tetO-positive, doxycycline-resistant ST-10 strain during 1999 to 2002 and a predominant tetM-positive doxycycline-resistant ST-62 strain during 2007 to 2010.

Genetic Diversity of Streptococcus equi subsp. zooepidemicus and Doxycycline Resistance in Kennelled Dogs

PubMed Central

Chalker, Victoria J.; Waller, Andrew; Webb, Katy; Spearing, Emma; Crosse, Patricia; Brownlie, Joe

2012-01-01

The genetic diversity and antibiotic resistance profiles of 38 Streptococcus equi subsp. zooepidemicus isolates were determined from a kennelled canine population during two outbreaks of hemorrhagic pneumonia (1999 to 2002 and 2007 to 2010). Analysis of the szp gene hypervariable region and the 16S-23S rRNA intergenic spacer region and multilocus sequence typing (MLST) indicated a predominant tetO-positive, doxycycline-resistant ST-10 strain during 1999 to 2002 and a predominant tetM-positive doxycycline-resistant ST-62 strain during 2007 to 2010. PMID:22495558

Influence of bacterial interactions on pneumococcal colonization of the nasopharynx

PubMed Central

Shak, Joshua R.; Vidal, Jorge E.; Klugman, Keith P.

2013-01-01

Streptococcus pneumoniae (the pneumococcus) is a common commensal inhabitant of the nasopharynx and a frequent etiologic agent in serious diseases such as pneumonia, otitis media, bacteremia, and meningitis. Multiple pneumococcal strains can colonize the nasopharynx, which is also home to many other bacterial species. Intraspecies and interspecies interactions influence pneumococcal carriage in important ways. Co-colonization by two or more pneumococcal strains has implications for vaccine serotype replacement, carriage detection, and pneumonia diagnostics. Interactions between the pneumococcus and other bacterial species alter carriage prevalence, modulate virulence, and affect biofilm formation. By examining these interactions, this review highlights how the bacterial ecosystem of the nasopharynx changes the nature and course of pneumococcal carriage. PMID:23273566

NAMRU-3 Reprint Accession List 1984. Number 14.

DTIC Science & Technology

1985-01-01

and FARID, Z.: Treatment of Ancylostomiasis and Ascariasis with Albendazole . Ann. Trop. Med. Parasitol., 78(l):81-82, 1984. *1390 MANSOUR, N.S., SOLIMAN...1388 Streptococcus pneumoniae 1388 CHEMOTHERAPY Albendazole in the treatment of ancylostomiasis and ascariasis 1389 Praziquantel in the treatment of

BARRIERS TO GENETIC EXCHANGE BETWEEN BACTERIAL SPECIES: STREPTOCOCCUS PNEUMONIAE TRANSFORMATION. (R825348)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Vancomycin tolerance in clinical and laboratory Streptococcus pneumoniae isolates depends on reduced enzyme activity of the major LytA autolysin or cooperation between CiaH histidine kinase and capsular polysaccharide.

PubMed

Moscoso, Miriam; Domenech, Mirian; García, Ernesto

2010-08-01

Vancomycin is frequently added to standard therapy for pneumococcal meningitis. Although vancomycin-resistant Streptococcus pneumoniae strains have not been isolated, reports on the emergence of vancomycin-tolerant pneumococci are a cause of concern. To date, the molecular basis of vancomycin tolerance in S. pneumoniae is essentially unknown. We examined two vancomycin-tolerant clinical isolates, i.e. a purported autolysin negative (LytA(-)), serotype 23F isolate (strain S3) and the serotype 14 strain 'Tupelo', which is considered a paradigm of vancomycin tolerance. S3 was characterized here as carrying a frameshift mutation in the lytA gene encoding the main pneumococcal autolysin. The vancomycin tolerance of strain S3 was abolished by transformation to the autolysin-proficient phenotype. The original Tupelo strain was discovered to be a mixture: a strain showing a vancomycin-tolerant phenotype (Tupelo_VT) and a vancomycin-nontolerant strain (Tupelo_VNT). The two strains differed only in terms of a single mutation in the ciaH gene present in the VT strain. Most interestingly, although the vancomycin tolerance of Tupelo_VT could be overcome by increasing the LytA dosage upon transformation by a multicopy plasmid or by externally adding the autolysin, we show that vancomycin tolerance in S. pneumoniae requires the simultaneous presence of a mutated CiaH histidine kinase and capsular polysaccharide. © 2010 Blackwell Publishing Ltd.

Differential Recognition and Hydrolysis of Host Carbohydrate Antigens by Streptococcus pneumoniae Family 98 Glycoside Hydrolases

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

Higgins, M.; Whitworth, G; El Warry, N

2009-01-01

The presence of a fucose utilization operon in the Streptococcus pneumoniae genome and its established importance in virulence indicates a reliance of this bacterium on the harvesting of host fucose-containing glycans. The identities of these glycans, however, and how they are harvested is presently unknown. The biochemical and high resolution x-ray crystallographic analysis of two family 98 glycoside hydrolases (GH98s) from distinctive forms of the fucose utilization operon that originate from different S. pneumoniae strains reveal that one enzyme, the predominant type among pneumococcal isolates, has a unique endo-{beta}-galactosidase activity on the LewisY antigen. Altered active site topography in themore » other species of GH98 enzyme tune its endo-{beta}-galactosidase activity to the blood group A and B antigens. Despite their different specificities, these enzymes, and by extension all family 98 glycoside hydrolases, use an inverting catalytic mechanism. Many bacterial and viral pathogens exploit host carbohydrate antigens for adherence as a precursor to colonization or infection. However, this is the first evidence of bacterial endoglycosidase enzymes that are known to play a role in virulence and are specific for distinct host carbohydrate antigens. The strain-specific distribution of two distinct types of GH98 enzymes further suggests that S. pneumoniae strains may specialize to exploit host-specific antigens that vary from host to host, a factor that may feature in whether a strain is capable of colonizing a host or establishing an invasive infection.« less

Determination of the antimicrobial susceptibilities of Canadian isolates of Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Canadian Antimicrobial Study Group.

PubMed

Blondeau, J M; Suter, M; Borsos, S

1999-03-01

The susceptibility of Canadian isolates of three respiratory tract pathogens (Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae) to several antimicrobial agents were tested by two different methods. Beta-lactamase was produced by 68/211 (32.2%) of H. influenzae isolates and 64/75 (85.3%) of M. catarrhalis isolates. For S. pneumoniae, 19/156 (12.2%) isolates were resistant to penicillin (MIC > or = 0.12 mg/L) and two isolates had MICs of 1.5 mg/L. For some combinations of agents and organisms, different methods gave different values for the proportion of isolates susceptible. Regardless of methodology, for H. influenzae, the most active antimicrobials based on proportion of strains susceptible were ciprofloxacin (100%) and cefpodoxime (98.5-100%). For M. catarrhalis, the most active agents were azithromycin, cefaclor, cefixime, cefpodoxime, cefuroxime, ciprofloxacin, clarithromycin and loracarbef (100% each); the least active was ampicillin. Against penicillin-sensitive and -resistant pneumococci, the activity was not significantly different for azithromycin and clarithromycin (93.4-100%) and ciprofloxacin (MIC90 2.0 and 1.5 mg/L, respectively) but was different for cefuroxime (99.3% and 31.6%, respectively), cefaclor (MIC90 0.75 and > or = 256 mg/L, respectively), cefpodoxime (MIC90 0.047 and 1.5 mg/L, respectively) and loracarbef (MIC90 0.75 and > or = 256 mg/L, respectively). This study indicates the increasing incidence, in Canada, of beta-lactamase resistance in H. influenzae and M. catarrhalis and penicillin resistance in S. pneumoniae.

Sequencing of the variable region of rpsB to discriminate between Streptococcus pneumoniae and other streptococcal species.

PubMed

Wyllie, Anne L; Pannekoek, Yvonne; Bovenkerk, Sandra; van Engelsdorp Gastelaars, Jody; Ferwerda, Bart; van de Beek, Diederik; Sanders, Elisabeth A M; Trzciński, Krzysztof; van der Ende, Arie

2017-09-01

The vast majority of streptococci colonizing the human upper respiratory tract are commensals, only sporadically implicated in disease. Of these, the most pathogenic is Mitis group member, Streptococcus pneumoniae Phenotypic and genetic similarities between streptococci can cause difficulties in species identification. Using ribosomal S2-gene sequences extracted from whole-genome sequences published from 501 streptococci, we developed a method to identify streptococcal species. We validated this method on non-pneumococcal isolates cultured from cases of severe streptococcal disease ( n = 101) and from carriage ( n = 103), and on non-typeable pneumococci from asymptomatic individuals ( n = 17) and on whole-genome sequences of 1157 pneumococcal isolates from meningitis in the Netherlands. Following this, we tested 221 streptococcal isolates in molecular assays originally assumed specific for S. pneumoniae , targeting cpsA , lytA , piaB , ply , Spn9802, zmpC and capsule-type-specific genes. Cluster analysis of S2-sequences showed grouping according to species in line with published phylogenies of streptococcal core genomes. S2-typing convincingly distinguished pneumococci from non-pneumococcal species (99.2% sensitivity, 100% specificity). Molecular assays targeting regions of lytA and piaB were 100% specific for S. pneumoniae , whereas assays targeting cpsA , ply , Spn9802, zmpC and selected serotype-specific assays (but not capsular sequence typing) showed a lack of specificity. False positive results were over-represented in species associated with carriage, although no particular confounding signal was unique for carriage isolates. © 2017 The Authors.

Sequencing of the variable region of rpsB to discriminate between Streptococcus pneumoniae and other streptococcal species

PubMed Central

Pannekoek, Yvonne; Bovenkerk, Sandra; van Engelsdorp Gastelaars, Jody; Ferwerda, Bart; van de Beek, Diederik; Sanders, Elisabeth A. M.; Trzciński, Krzysztof; van der Ende, Arie

2017-01-01

The vast majority of streptococci colonizing the human upper respiratory tract are commensals, only sporadically implicated in disease. Of these, the most pathogenic is Mitis group member, Streptococcus pneumoniae. Phenotypic and genetic similarities between streptococci can cause difficulties in species identification. Using ribosomal S2-gene sequences extracted from whole-genome sequences published from 501 streptococci, we developed a method to identify streptococcal species. We validated this method on non-pneumococcal isolates cultured from cases of severe streptococcal disease (n = 101) and from carriage (n = 103), and on non-typeable pneumococci from asymptomatic individuals (n = 17) and on whole-genome sequences of 1157 pneumococcal isolates from meningitis in the Netherlands. Following this, we tested 221 streptococcal isolates in molecular assays originally assumed specific for S. pneumoniae, targeting cpsA, lytA, piaB, ply, Spn9802, zmpC and capsule-type-specific genes. Cluster analysis of S2-sequences showed grouping according to species in line with published phylogenies of streptococcal core genomes. S2-typing convincingly distinguished pneumococci from non-pneumococcal species (99.2% sensitivity, 100% specificity). Molecular assays targeting regions of lytA and piaB were 100% specific for S. pneumoniae, whereas assays targeting cpsA, ply, Spn9802, zmpC and selected serotype-specific assays (but not capsular sequence typing) showed a lack of specificity. False positive results were over-represented in species associated with carriage, although no particular confounding signal was unique for carriage isolates. PMID:28931649

Septicaemia models using Streptococcus pneumoniae and Listeria monocytogenes: understanding the role of complement properdin.

PubMed

Dupont, Aline; Mohamed, Fatima; Salehen, Nur'Ain; Glenn, Sarah; Francescut, Lorenza; Adib, Rozita; Byrne, Simon; Brewin, Hannah; Elliott, Irina; Richards, Luke; Dimitrova, Petya; Schwaeble, Wilhelm; Ivanovska, Nina; Kadioglu, Aras; Machado, Lee R; Andrew, Peter W; Stover, Cordula

2014-08-01

Streptococcus pneumoniae and Listeria monocytogenes, pathogens which can cause severe infectious disease in human, were used to infect properdin-deficient and wildtype mice. The aim was to deduce a role for properdin, positive regulator of the alternative pathway of complement activation, by comparing and contrasting the immune response of the two genotypes in vivo. We show that properdin-deficient and wildtype mice mounted antipneumococcal serotype-specific IgM antibodies, which were protective. Properdin-deficient mice, however, had increased survival in the model of streptococcal pneumonia and sepsis. Low activity of the classical pathway of complement and modulation of FcγR2b expression appear to be pathogenically involved. In listeriosis, however, properdin-deficient mice had reduced survival and a dendritic cell population that was impaired in maturation and activity. In vitro analyses of splenocytes and bone marrow-derived myeloid cells support the view that the opposing outcomes of properdin-deficient and wildtype mice in these two infection models is likely to be due to a skewing of macrophage activity to an M2 phenotype in the properdin-deficient mice. The phenotypes observed thus appear to reflect the extent to which M2- or M1-polarised macrophages are involved in the immune responses to S. pneumoniae and L. monocytogenes. We conclude that properdin controls the strength of immune responses by affecting humoral as well as cellular phenotypes during acute bacterial infection and ensuing inflammation.

Microbial aetiology, outcomes, and costs of hospitalisation for community-acquired pneumonia; an observational analysis

PubMed Central

2014-01-01

Background The aim of this study was to investigate the clinical outcome and especially costs of hospitalisation for community-acquired pneumonia (CAP) in relation to microbial aetiology. This knowledge is indispensable to estimate cost-effectiveness of new strategies aiming to prevent and/or improve clinical outcome of CAP. Methods We performed our observational analysis in a cohort of 505 patients hospitalised with confirmed CAP between 2004 and 2010. Hospital administrative databases were extracted for all resource utilisation on a patient level. Resource items were grouped in seven categories: general ward nursing, nursing on ICU, clinical chemistry laboratory tests, microbiology exams, radiology exams, medication drugs, and other.linear regression analyses were conducted to identify variables predicting costs of hospitalisation for CAP. Results Streptococcus pneumoniae was the most identified causative pathogen (25%), followed by Coxiella burnetii (6%) and Haemophilus influenzae (5%). Overall median length of hospital stay was 8.5 days, in-hospital mortality rate was 4.8%. Total median hospital costs per patient were €3,899 (IQR 2,911-5,684). General ward nursing costs represented the largest share (57%), followed by nursing on the intensive care unit (16%) and diagnostic microbiological tests (9%). In multivariate regression analysis, class IV-V Pneumonia Severity Index (indicative for severe disease), Staphylococcus aureus, or Streptococcus pneumonia as causative pathogen, were independent cost driving factors. Coxiella burnetii was a cost-limiting factor. Conclusions Median costs of hospitalisation for CAP are almost €4,000 per patient. Nursing costs are the main cause of these costs.. Apart from prevention, low-cost interventions aimed at reducing length of hospital stay therefore will most likely be cost-effective. PMID:24938861

Streptococcus pneumoniae pharyngeal colonization in school-age children and adolescents with cancer.

PubMed

Principi, Nicola; Preti, Valentina; Gaspari, Stefania; Colombini, Antonella; Zecca, Marco; Terranova, Leonardo; Cefalo, Maria Giuseppina; Ierardi, Valentina; Pelucchi, Claudio; Esposito, Susanna

2016-01-01

Patients with cancer, particularly those with hematologic malignancies, are at an increased risk of invasive pneumococcal disease (IPD) and they are included in the list of subjects for whom pneumococcal vaccination is recommended. The main aim of this study was to evaluate Streptococcus pneumoniae colonization in school-aged children and adolescents with cancer to determine the potential protective efficacy of 13-valent pneumococcal conjugate vaccine (PCV13). An oropharyngeal swab was obtained from 277 patients (age range 6-17 years) with cancer during routine clinical visits and analyzed for S. pneumoniae using real-time polymerase chain reaction. S. pneumoniae was identified in 52 patients (18.8%), including 47/235 (20.0%) with hematologic malignancies and 5/42 (11.9%) with solid tumors. Colonization declined significantly with an increase in age (odds ratio [OR] 0.34, 95% confidence interval [CI] 0.16-0.71, and OR 0.30, 95% CI 0.11-0.82 in children aged 10-14 and ≥15 years, respectively, as compared to those <10 years). Carriage was more common among patients with leukemia or lymphoma than in children with solid tumors. Co-trimoxazole prophylaxis was significantly associated with reduced pneumococcal carriage (OR 0.41, 95% CI 0.19-0.89). A total of 15/58 (25.9%) and 26/216 (12.0%) children were colonized by PCV13 serotypes among cancer patients previously vaccinated and not vaccinated with 7-valent pneumococcal conjugate vaccine (PCV7), respectively. In conclusion, this study indicates that children and adolescents with cancer are frequently colonized by S. pneumoniae. Because most of the carried serotypes are included in PCV13, this vaccine is presently the best solution to reduce the risk of IPD in these patients.

Identification of Alloiococcus otitidis, Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae in Children With Otitis Media With Effusion

PubMed Central

Farajzadah Sheikh, Ahmad; Saki, Nader; Roointan, Mitra; Ranjbar, Reza; Yadyad, Mohammad Jaafar; Kaydani, Abbas; Aslani, Sajad; Babaei, Mansoor; Goodarzi, Hamed

2015-01-01

Background: Based on many studies, otitis media with effusion (OME) is one of the major causes of childhood hearing loss, social malformation and medical costs. The pathogenesis still remains unclear, though it is known that this complication is closely related to bacterial infections. Alloiococcus otitidis, Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis are the most common bacterial pathogens isolated from middle ear effusions (MEEs). Objectives: Due to the prevalence of OME in children, we decided to investigate bacterial agents that cause diseases such as A. otitidis, H. influenzae, S. pneumonia and M. catarrhalis in these subjects. Patients and Methods: Forty-five children between one and 15 years of age were selected for this study. Seventy specimens were collected from MEE by myringotomy and inoculated in PBS buffer. Conventional culture and PCR methods were used for identification of bacterial agents. Results: The bacterial cultures in 8.6% of samples were positive by conventional culture, with A. otitidis, M. catarrhalis and S. pneumoniae present in 1.4%, 2.9% and 4.3% of samples, respectively. No H. influenzae was isolated. By the PCR method, A. otitidis was the most frequently isolated bacterium, found in 25.7% of samples, followed by S. pneumoniae, M. catarrhalis and H. influenzae, which were identified in 20%, 12% and 20% of samples, respectively. Overall, 55 out of 70 samples were positive by both the PCR and culture method. Conclusions: It can be concluded that A. otitidis was the major causative agent of MEE in children with OME. Therefore clinicians should be aware that bacterial infection plays an important role in the progression of acute otitis media to OME in children of our region. PMID:25861433

Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis

PubMed Central

Adegbola, Richard A.; DeAntonio, Rodrigo; Hill, Philip C.; Roca, Anna; Usuf, Effua; Hoet, Bernard; Greenwood, Brian M.

2014-01-01

Background Infection with Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide, especially in low income countries where pneumococcal conjugate vaccines (PCVs) are still underused. In countries where PCVs have been introduced, much of their efficacy has resulted from their impact on nasopharyngeal carriage in vaccinated children. Understanding the epidemiology of carriage for S. pneumoniae and other common respiratory bacteria in developing countries is crucial for implementing appropriate vaccination strategies and evaluating their impact. Methods and Findings We have systematically reviewed published studies reporting nasopharyngeal or oropharyngeal carriage of S. pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Neisseria meningitidis in children and adults in low and lower-middle income countries. Studies reporting pneumococcal carriage for healthy children <5 years of age were selected for a meta-analysis. The prevalences of carriage for S. pneumoniae, H. influenzae, and M. catarrhalis were generally higher in low income than in lower-middle income countries and were higher in young children than in adults. The prevalence of S. aureus was high in neonates. Meta-analysis of data from young children before the introduction of PCVs showed a pooled prevalence estimate of 64.8% (95% confidence interval, 49.8%–76.1%) in low income countries and 47.8% (95% confidence interval, 44.7%–50.8%) in lower-middle income countries. The most frequent serotypes were 6A, 6B, 19A, 19F, and 23F. Conclusions In low and lower-middle income countries, pneumococcal carriage is frequent, especially in children, and the spectrum of serotypes is wide. However, because data are limited, additional studies are needed to adequately assess the impact of PCV introduction on carriage of respiratory bacteria in these countries. PMID:25084351

Individual risk factors associated with nasopharyngeal colonization with Streptococcus pneumoniae and Haemophilus influenzae: a Japanese birth cohort study.

PubMed

Otsuka, Taketo; Chang, Bin; Shirai, Takatoshi; Iwaya, Atsushi; Wada, Akihito; Yamanaka, Noboru; Okazaki, Minoru

2013-07-01

The first step in a bacterial disease is the establishment of nasopharyngeal carriage. We conducted a birth cohort study to identify factors associated with colonization in healthy children and evaluate the serotype distributions and resistances of Streptococcus pneumoniae/Haemophilus influenzae. Nasopharyngeal cultures were obtained from 349 subjects at 5 time points coinciding with health checkups (4, 7, 10, 18 and 36 months). A total of 551 S. pneumoniae (penicillin resistance rate: 46.3%) and 301 H. influenzae (ampicillin resistance rate: 44.5%) isolates were obtained from 1654 samples. In this study, 47.5% and 60.9% of S. pneumoniae isolates were included in the serotypes of 7- and 13-valent pneumococcal conjugate vaccines, respectively. Analyzing by Cox proportional hazards models, cohabiting older sibling(s) attending day-care (hazard ratios: 2.064-3.518, P < 0.001) and an early start of day-care attendance by the subjects themselves (2.259-2.439, P < 0.001) were associated with a higher risk of early colonization regardless of their susceptibility. Recent exposure to antimicrobials was also significantly associated with increased risk of colonization (odds ratios: 2.032-2.999, P < 0.001) but not with resistance rates. This data indicated that introduction of appropriate antimicrobial usage in areas of overuse of antimicrobials could contribute to lower colonization of S. pneumoniae/H. influenzae, resulting in a decrease in the absolute number of resistant isolates. Strategies to control transmission at day-care centers or from older sibling(s) as well as appropriate use of antimicrobials are essential for reducing colonization and the absolute number of resistant isolates.

Streptococcus pneumoniae bacteraemia due to parotitis in a patient with systemic sclerosis and secondary Sjögren's syndrome.

PubMed

Yii, Irene Yuen Lin; Tan, Jamie Bee Xian; Fong, Warren Weng Seng

2016-10-01

Invasive pneumococcal disease is an uncommon and notifiable disease in Singapore. It is often associated with significant morbidity and mortality. We report a rare case of invasive pneumococcal bacteraemia due to parotitis in a patient with systemic sclerosis and secondary Sjögren's syndrome. We also present a retrospective review of Streptococcus pneumoniae bacteraemia cases in Singapore General Hospital from January 2011 to April 2016. A 59-year-old Malay lady with a history of systemic sclerosis with secondary Sjögren's syndrome presented with fever and left parotid gland swelling. Clinical examination revealed poor salivary pooling and left parotid swelling without fluctuance. Ultrasound of the left parotid gland confirmed acute parotitis without evidence of abscess or sialolithiasis. Blood cultures were positive for S. pneumoniae . She was diagnosed to have invasive pneumococcal bacteraemia secondary to acute parotitis, and treated with intravenous benzylpenicillin with clearance of bacteraemia after 3 days. Upon discharge, her antibiotics were changed to intravenous ceftriaxone to facilitate outpatient parenteral antibiotic therapy for another 2 weeks. She responded favourably to antibiotics at follow-up, with no complications from the bacteraemia. A review of the microbiological records of the Singapore General Hospital revealed 116 cases of pneumococcal bacteraemia, most (80.3 %) of which were due to pneumonia. None were due to parotitis. S. pneumoniae parotitis and subsequent bacteraemia is rare. Prompt recognition of the disease and appropriate use of antibiotics are important. This case highlights that close communication between healthcare workers (microbiologist, rheumatologist and infectious disease specialist) is essential in ensuring good clinical outcomes in patients with a potentially fatal disease.

SpxB is a suicide gene of Streptococcus pneumoniae and confers a selective advantage in an in vivo competitive colonization model.

PubMed

Regev-Yochay, Gili; Trzcinski, Krzysztof; Thompson, Claudette M; Lipsitch, Marc; Malley, Richard

2007-09-01

The human bacterial pathogen Streptococcus pneumoniae dies spontaneously upon reaching stationary phase. The extent of S. pneumoniae death at stationary phase is unusual in bacteria and has been conventionally attributed to autolysis by the LytA amidase. In this study, we show that spontaneous pneumococcal death is due to hydrogen peroxide (H(2)O(2)), not LytA, and that the gene responsible for H(2)O(2) production (spxB) also confers a survival advantage in colonization. Survival of S. pneumoniae in stationary phase was significantly prolonged by eliminating H(2)O(2) in any of three ways: chemically by supplementing the media with catalase, metabolically by growing the bacteria under anaerobic conditions, or genetically by constructing DeltaspxB mutants that do not produce H(2)O(2). Likewise, addition of H(2)O(2) to exponentially growing S. pneumoniae resulted in a death rate similar to that of cells in stationary phase. While DeltalytA mutants did not lyse at stationary phase, they died at a rate similar to that of the wild-type strain. Furthermore, we show that the death process induced by H(2)O(2) has features of apoptosis, as evidenced by increased annexin V staining, decreased DNA content, and appearance as assessed by transmission electron microscopy. Finally, in an in vivo rat model of competitive colonization, the presence of spxB conferred a selective advantage over the DeltaspxB mutant, suggesting an explanation for the persistence of this gene. We conclude that a suicide gene of pneumococcus is spxB, which induces an apoptosis-like death in pneumococci and confers a selective advantage in nasopharyngeal cocolonization.

SpxB Is a Suicide Gene of Streptococcus pneumoniae and Confers a Selective Advantage in an In Vivo Competitive Colonization Model▿

PubMed Central

Regev-Yochay, Gili; Trzcinski, Krzysztof; Thompson, Claudette M.; Lipsitch, Marc; Malley, Richard

2007-01-01

The human bacterial pathogen Streptococcus pneumoniae dies spontaneously upon reaching stationary phase. The extent of S. pneumoniae death at stationary phase is unusual in bacteria and has been conventionally attributed to autolysis by the LytA amidase. In this study, we show that spontaneous pneumococcal death is due to hydrogen peroxide (H2O2), not LytA, and that the gene responsible for H2O2 production (spxB) also confers a survival advantage in colonization. Survival of S. pneumoniae in stationary phase was significantly prolonged by eliminating H2O2 in any of three ways: chemically by supplementing the media with catalase, metabolically by growing the bacteria under anaerobic conditions, or genetically by constructing ΔspxB mutants that do not produce H2O2. Likewise, addition of H2O2 to exponentially growing S. pneumoniae resulted in a death rate similar to that of cells in stationary phase. While ΔlytA mutants did not lyse at stationary phase, they died at a rate similar to that of the wild-type strain. Furthermore, we show that the death process induced by H2O2 has features of apoptosis, as evidenced by increased annexin V staining, decreased DNA content, and appearance as assessed by transmission electron microscopy. Finally, in an in vivo rat model of competitive colonization, the presence of spxB conferred a selective advantage over the ΔspxB mutant, suggesting an explanation for the persistence of this gene. We conclude that a suicide gene of pneumococcus is spxB, which induces an apoptosis-like death in pneumococci and confers a selective advantage in nasopharyngeal cocolonization. PMID:17631628

Activity of Gemifloxacin against Quinolone-Resistant Streptococcus pneumoniae Strains In Vitro and in a Mouse Pneumonia Model

PubMed Central

Azoulay-Dupuis, E.; Bédos, J. P.; Mohler, J.; Moine, P.; Cherbuliez, C.; Peytavin, G.; Fantin, B.; Köhler, T.

2005-01-01

Gemifloxacin is a novel fluoronaphthyridone quinolone with enhanced in vitro activity against Streptococcus pneumoniae. We investigated the activities of gemifloxacin and trovafloxacin, their abilities to select for resistance in vitro and in vivo, and their efficacies in a mouse model of acute pneumonia. Immunocompetent Swiss mice were infected with 105 CFU of a virulent, encapsulated S. pneumoniae strain, P-4241, or its isogenic parC, gyrA, parC gyrA, and efflux mutant derivatives (serotype 3); and leukopenic mice were infected with 107 CFU of two poorly virulent clinical strains (serotype 11A) carrying either a parE mutation or a parC, gyrA, and parE triple mutation. The drugs were administered six times every 12 h, starting at either 3 or 18 h postinfection. In vitro, gemifloxacin was the most potent agent against strains with and without acquired resistance to fluoroquinolones. While control mice died within 6 days, gemifloxacin at doses of 25 and 50 mg/kg of body weight was highly effective (survival rates, 90 to 100%) against the wild-type strain and against mutants harboring a single mutation, corresponding to area under the time-versus-serum concentration curve at 24 h (AUC24)/MIC ratios of 56.5 to 113, and provided a 40% survival rate against a mutant with a double mutation (parC and gyrA). A total AUC24/MIC ratio of 28.5 was associated with poor efficacy and the emergence of resistant mutants. Trovafloxacin was as effective as gemifloxacin against mutants with single mutations but did not provide any protection against the mutant with double mutations, despite treatment with a high dose of 200 mg/kg. Gemifloxacin preferentially selected for parC mutants both in vitro and in vivo. PMID:15728901

Glycolytic enzymes associated with the cell surface of Streptococcus pneumoniae are antigenic in humans and elicit protective immune responses in the mouse

PubMed Central

LING, E; FELDMAN, G; PORTNOI, M; DAGAN, R; OVERWEG, K; MULHOLLAND, F; CHALIFA-CASPI, V; WELLS, J; MIZRACHI-NEBENZAHL, Y

2004-01-01

Streptococcus pneumoniae is a leading cause of otitis media, sinusitis, pneumonia, bacteraemia and meningitis worldwide. The drawbacks associated with the limited number of various capsular polysaccharides that can be included in the polysaccharide-based vaccines focuses much attention on pneumococcal proteins as vaccine candidates. We extracted an enriched cell wall fraction from S. pneumoniae WU2. Approximately 150 soluble proteins could be identified by 2D gel electrophoresis. The proteins were screened by 2D-Western blotting using sera that were obtained longitudinally from children attending day-care centres at 18, 30 and 42 months of age and sera from healthy adult volunteers. The proteins were further identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Seventeen proteins were antigenic in children and adults, of which 13 showed an increasing antibody response with age in all eight children analysed. Two immunogenic proteins, fructose–bisphosphate aldolase (FBA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and a control protein with known low immunogenicity, heat shock protein 70 (DnaK), were expressed in Escherichia coli, purified and used to immunize mice. Mouse antibodies elicited to the recombinant (r) FBA and rGAPDH were cross-reactive with several genetically unrelated strains of different serotypes and conferred protection to respiratory challenge with virulent pneumococci. In addition, the FBA used in this study (NP_345117) does not have a human ortholog and warrants further investigation as a candidate for a pneumococcal vaccine. In conclusion, the immunoproteomics based approach utilized in the present study appears to be a suitable tool for identification of novel S. pneumoniae vaccine candidates. PMID:15498039

Comparison of different culture media and storage temperatures for the long-term preservation of Streptococcus pneumoniae in the tropics.

PubMed

Siberry, G; Brahmadathan, K N; Pandian, R; Lalitha, M K; Steinhoff, M C; John, T J

2001-01-01

The preservation of Streptococcus pneumoniae by standard freezing methods for subsequent tests--such as serotyping and antibiotic susceptibility--is not possible or is difficult in many developing countries because of the high cost of equipment, inadequate equipment maintenance, and irregular power supply. We evaluated alternative low-cost methods, by comparing different culture media and storage temperatures. Clinical isolates of five capsular types (1, 5, 7, 19, and 23) of S. pneumoniae were preserved in rabbit blood, sheep blood, skimmed milk, or glycerol-chocolate broth, and stored at -20 degrees C or -70 degrees C. The cultures were also preserved by lyophilization or sand desiccation, followed by storage at room temperature and 4 degrees C. The viability of the preserved cultures was determined by making serial colony counts on day 0 and after 1 week, 4 weeks, 4 months and 16 months. The viability of cultures preserved by sand desiccation and storage at 4 degrees C was also determined every 6 months for up to 68 months. Irrespective of the media used, cultures maintained at -20 degrees C became nonviable by the fourth month, while those maintained at -70 degrees C were still viable at 16 months. Cultures preserved by lyophilization or sand desiccation lost their viability by the fourth month when maintained at local room temperature (30-42 degrees C), but remained viable when stored at 4 degrees C for up to 68 months. Our results confirm that freezing at -70 degrees C, or lyophilization and storage at 4 degrees C are the ideal methods for the preservation of S. pneumoniae. In laboratories where lyophilization is not feasible, sand desiccation and storage at 4 degrees C offers an alternative low-cost method for the long-term preservation of S. pneumoniae.

Density Interactions between Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus in the Nasopharynx of Young Peruvian Children

PubMed Central

Chien, Yu-Wen; Vidal, Jorge E.; Grijalva, Carlos G.; Bozio, Catherine; Edwards, Kathryn M.; Williams, John V.; Griffin, Marie R.; Verastegui, Hector; Hartinger, Stella M.; Gil, Ana I.; Lanata, Claudio F.; Klugman, Keith P.

2012-01-01

Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus are commonly carried in the nasopharynx (NP) of young children, and have been speculated to interact with each other. Although earlier studies used cultures alone to assess these interactions, the addition of real-time quantitative polymerase chain reaction (qPCR) provides further insight into these interactions. We compared results of culture and qPCR for the detection of these three bacteria in 446 NP samples collected from 360 healthy young children in a prospective cohort study in the Peruvian Andes. Patterns of concurrent bacterial colonization were studied using repeated measures logistic regression models with generalized estimating equations. Spearman correlation coefficients were employed to assess correlations among bacterial densities. At a bacterial density <105 colony forming units (CFU)/ml measured by qPCR, culture detected significantly less carriers (P<0.0001) for all three pathogens, than at a bacterial density >105 CFU/ml. In addition, there was a positive association between S. pneumoniae and H. influenzae colonization measured by both culture (OR 3.11 – 3.17, p < 0.001) and qPCR (OR 1.95 – 1.97, p < 0.01). The densities of S. pneumoniae and H. influenzae, measured by qPCR, were positively correlated (correlation coefficient 0.32, p < 0.001). A negative association was found between the presence of S. pneumoniae and S. aureus in carriage with both culture (OR 0.45, p = 0.024) and qPCR (OR 0.61, p < 0.05). The impact of density on detection by culture and the observed density-related interactions support use of qPCR in additional studies to examine vaccine effects on diverse bacterial species. PMID:22935873

Density interactions among Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus in the nasopharynx of young Peruvian children.

PubMed

Chien, Yu-Wen; Vidal, Jorge E; Grijalva, Carlos G; Bozio, Catherine; Edwards, Kathryn M; Williams, John V; Griffin, Marie R; Verastegui, Hector; Hartinger, Stella M; Gil, Ana I; Lanata, Claudio F; Klugman, Keith P

2013-01-01

Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus are commonly carried in the nasopharynx of young children, and have been speculated to interact with each other. Although earlier studies used cultures alone to assess these interactions, the addition of real-time quantitative polymerase chain reaction (qPCR) provides further insight into these interactions. We compared results of culture and qPCR for the detection of these 3 bacteria in 446 nasopharynx samples collected from 360 healthy young children in a prospective cohort study in the Peruvian Andes. Patterns of concurrent bacterial colonization were studied using repeated measures logistic regression models with generalized estimating equations. Spearman correlation coefficients were used to assess correlations among bacterial densities. At a bacterial density <10 colony forming units/mL measured by qPCR, culture detected significantly less carriers (P < 0.0001) for all 3 pathogens, than at a bacterial density >10 colony forming units/mL. In addition, there was a positive association between S. pneumoniae and H. influenzae colonization measured by both culture (odds ratio [OR] 3.11-3.17, P < 0.001) and qPCR (OR 1.95-1.97, P < 0.01). The densities of S. pneumoniae and H. influenzae, measured by qPCR, were positively correlated (correlation coefficient 0.32, P < 0.001). A negative association was found between the presence of S. pneumoniae and Staphylococcus aureus in carriage with both culture (OR 0.45, P = 0.024) and qPCR (OR 0.61, P < 0.05). The impact of density on detection by culture and the observed density-related interactions support use of qPCR in additional studies to examine vaccine effects on diverse bacterial species.

Components of Streptococcus pneumoniae suppress allergic airways disease and NKT cells by inducing regulatory T cells.

PubMed

Thorburn, Alison N; Foster, Paul S; Gibson, Peter G; Hansbro, Philip M

2012-05-01

Asthma is an allergic airways disease (AAD) caused by dysregulated immune responses and characterized by eosinophilic inflammation, mucus hypersecretion, and airway hyperresponsiveness (AHR). NKT cells have been shown to contribute to AHR in some mouse models. Conversely, regulatory T cells (Tregs) control aberrant immune responses and maintain homeostasis. Recent evidence suggests that Streptococcus pneumoniae induces Tregs that have potential to be harnessed therapeutically for asthma. In this study, mouse models of AAD were used to identify the S. pneumoniae components that have suppressive properties, and the mechanisms underlying suppression were investigated. We tested the suppressive capacity of type-3-polysaccharide (T3P), isolated cell walls, pneumolysoid (Ply) and CpG. When coadministered, T3P + Ply suppressed the development of: eosinophilic inflammation, Th2 cytokine release, mucus hypersecretion, and AHR. Importantly, T3P + Ply also attenuated features of AAD when administered during established disease. We show that NKT cells contributed to the development of AAD and also were suppressed by T3P + Ply treatment. Furthermore, adoptive transfer of NKT cells induced AHR, which also could be reversed by T3P + Ply. T3P + Ply-induced Tregs were essential for the suppression of NKT cells and AAD, which was demonstrated by Treg depletion. Collectively, our results show that the S. pneumoniae components T3P + Ply suppress AAD through the induction of Tregs that blocked the activity of NKT cells. These data suggest that S. pneumoniae components may have potential as a therapeutic strategy for the suppression of allergic asthma through the induction of Tregs and suppression of NKT cells.

Impact of Intermittent Preventive Treatment in Pregnancy with Azithromycin-Containing Regimens on Maternal Nasopharyngeal Carriage and Antibiotic Sensitivity of Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus: a Cross-Sectional Survey at Delivery

PubMed Central

Unger, Holger W.; Aho, Celestine; Ome-Kaius, Maria; Wangnapi, Regina A.; Umbers, Alexandra J.; Jack, Wanda; Lafana, Alice; Michael, Audrey; Hanieh, Sarah; Siba, Peter; Mueller, Ivo; Greenhill, Andrew R.

2015-01-01

Sulfadoxine-pyrimethamine (SP) plus azithromycin (AZ) (SPAZ) has the potential for intermittent preventive treatment of malaria in pregnancy (IPTp), but its use could increase circulation of antibiotic-resistant bacteria associated with severe pediatric infections. We evaluated the effect of monthly SPAZ-IPTp compared to a single course of SP plus chloroquine (SPCQ) on maternal nasopharyngeal carriage and antibiotic susceptibility of Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus at delivery among 854 women participating in a randomized controlled trial in Papua New Guinea. Serotyping was performed, and antibiotic susceptibility was evaluated by disk diffusion and Etest. Potential risk factors for carriage were examined. Nasopharyngeal carriage at delivery of S. pneumoniae (SPAZ, 7.2% [30/418], versus SPCQ, 19.3% [84/436]; P < 0.001) and H. influenzae (2.9% [12/418] versus 6.0% [26/436], P = 0.028), but not S. aureus, was significantly reduced among women who had received SPAZ-IPTp. The number of macrolide-resistant pneumococcal isolates was small but increased in the SPAZ group (13.3% [4/30], versus SPCQ, 2.2% [2/91]; P = 0.033). The proportions of isolates with serotypes covered by the 13-valent pneumococcal conjugate vaccine were similar (SPAZ, 10.3% [3/29], versus SPCQ, 17.6% [16/91]; P = 0.352). Although macrolide-resistant isolates were rare, they were more commonly detected in women who had received SPAZ-IPTp, despite the significant reduction of maternal carriage of S. pneumoniae and H. influenzae observed in this group. Future studies on SPAZ-IPTp should evaluate carriage and persistence of macrolide-resistant S. pneumoniae and other pathogenic bacteria in both mothers and infants and assess the clinical significance of their circulation. PMID:25673788

Bactericidal effect of bovine lactoferrin and synthetic peptide lactoferrin chimera in Streptococcus pneumoniae and the decrease in luxS gene expression by lactoferrin.

PubMed

León-Sicairos, Nidia; Angulo-Zamudio, Uriel A; Vidal, Jorge E; López-Torres, Cynthia A; Bolscher, Jan G M; Nazmi, Kamran; Reyes-Cortes, Ruth; Reyes-López, Magda; de la Garza, Mireya; Canizalez-Román, Adrian

2014-10-01

Streptococcus pneumoniae (pneumococcus) is responsible for nearly one million child deaths annually. Pneumococcus causes infections such as pneumonia, otitis media, meningitis, and sepsis. The human immune system includes antibacterial peptides and proteins such as lactoferrin (LF), but its activity against pneumococcus is not fully understood. The aim of this work was to evaluate the bactericidal effect of bovine lactoferrin (bLF) and the synthetic LF-peptides lactoferricin (LFcin17-30), lactoferrampin (LFampin265-284), and LFchimera against S. pneumoniae planktonic cells. The mechanism of damage was also investigated, as well as the impact of these peptides on the transcription levels of genes known to encode important virulence factors. S. pneumoniae planktonic cells were treated with bLF, LFcin17-30, LFampin265-284 and LFchimera at different time points. The viability of treated planktonic cells was assessed by dilution and plating (in CFU/ml). The interaction between LF and LF-peptides coupled to fluorescein was visualized using a confocal microscope and flow cytometry, whereas the damage at structural levels was observed by electron microscopy. Damage to bacterial membranes was further evaluated by membrane permeabilization by use of propidium iodide and flow cytometry, and finally, the expression of pneumococcal genes was evaluated by qRT-PCR. bLF and LFchimera were the best bactericidal agents. bLF and peptides interacted with bacteria causing changes in the shape and size of the cell and membrane permeabilization. Moreover, the luxS gene was down-regulated in bacteria treated with LF. In conclusion, LF and LFchimera have a bactericidal effect, and LF down-regulates genes involved in the pathogenicity of pneumococcus, thus demonstrating potential as new agents for the treatment of pneumococcal infections.

Rapid and Accurate Diagnosis of Acute Pyogenic Meningitis Due to Streptococcus Pneumoniae, Haemophilus influenzae Type b and Neisseria meningitidis Using A Multiplex PCR Assay.

PubMed

Seth, Rajeev; Murthy, Peela Sree Ramchandra; Sistla, Sujatha; Subramanian, Mahadevan; Tamilarasu, Kadhiravan

2017-09-01

Acute bacterial meningitis is one of the major causes of morbidity and mortality in children and geriatric population, especially in developing countries. Methods of identification are standard culture and other phenotypic tests in many resource poor settings. To use molecular methods for the improvement of aetiological diagnosis of acute pyogenic meningitis in patients. CSF samples of 125 patients were included for the study. Gram staining and culture were performed according to standard procedures. Antigen was detected using commercial latex agglutination test kit. Multiplex PCR was performed using previously published primers and protocols. Fischer's exact test was used for finding association between presence of the disease and clinical/biochemical parameters, considering two tailed p<0.05 as statistically significant. Sensitivity, specificity, positive and negative predictive values were calculated using Graphpad QuicCalc software. A total of 39 cases (31.2%) were confirmed to be of acute pyogenic meningitis based on biochemical methods. Only 10/39 was positive for the three organisms tested. Multiplex PCR was able to detect one additional isolate each of Streptococcus pneumoniae and Haemophilus influenzae type b. When compared with multiplex PCR as the gold standard, culture and latex agglutination tests had same sensitivity (80%), specificity (100%), PPV (100%) and NPV (97.8%), whereas Gram stain had poor sensitivity (40%) and good specificity (95.6%). Detection rates were higher in multiplex PCR for the two organisms Streptococcus pneumoniae and Haemophilus influenzae type b. Multiplex PCR was more sensitive than culture or antigen detection, and employing this assay can significantly increase the speed and accuracy of identification of the pathogen.

Application of Quaternion in improving the quality of global sequence alignment scores for an ambiguous sequence target in Streptococcus pneumoniae DNA

NASA Astrophysics Data System (ADS)

Lestari, D.; Bustamam, A.; Novianti, T.; Ardaneswari, G.

2017-07-01

DNA sequence can be defined as a succession of letters, representing the order of nucleotides within DNA, using a permutation of four DNA base codes including adenine (A), guanine (G), cytosine (C), and thymine (T). The precise code of the sequences is determined using DNA sequencing methods and technologies, which have been developed since the 1970s and currently become highly developed, advanced and highly throughput sequencing technologies. So far, DNA sequencing has greatly accelerated biological and medical research and discovery. However, in some cases DNA sequencing could produce any ambiguous and not clear enough sequencing results that make them quite difficult to be determined whether these codes are A, T, G, or C. To solve these problems, in this study we can introduce other representation of DNA codes namely Quaternion Q = (PA, PT, PG, PC), where PA, PT, PG, PC are the probability of A, T, G, C bases that could appear in Q and PA + PT + PG + PC = 1. Furthermore, using Quaternion representations we are able to construct the improved scoring matrix for global sequence alignment processes, by applying a dot product method. Moreover, this scoring matrix produces better and higher quality of the match and mismatch score between two DNA base codes. In implementation, we applied the Needleman-Wunsch global sequence alignment algorithm using Octave, to analyze our target sequence which contains some ambiguous sequence data. The subject sequences are the DNA sequences of Streptococcus pneumoniae families obtained from the Genebank, meanwhile the target DNA sequence are received from our collaborator database. As the results we found the Quaternion representations improve the quality of the sequence alignment score and we can conclude that DNA sequence target has maximum similarity with Streptococcus pneumoniae.

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.

Changing epidemiology of melioidosis? A case of acute pulmonary melioidosis with fatal outcome imported from Brazil.

PubMed Central

Aardema, H.; Luijnenburg, E. M.; Salm, E. F.; Bijlmer, H. A.; Visser, C. E.; Van't Wout, J. W.

2005-01-01

Melioidosis is an infectious disease caused by Burkholderia pseudomallei. It is endemic in South East Asia and tropical regions of Northern Australia. Sporadic cases have been described elsewhere. In this article we present a case of acute pulmonary melioidosis with fatal outcome imported from Brazil. The most common pathogen causing severe community-acquired pneumonia in Brazil is Streptococcus pneumoniae. Other possible pathogens include Legionella spp., Mycoplasma pneumonia, Gram-negative rods and viruses. There are few reports of melioidosis in the Americas. This article represents the second known human case of melioidosis from Brazil. Recognition of melioidosis as a possible cause of severe pneumonia, even if a patient has not been travelling in a highly endemic area, is important because of the therapeutic consequences. The epidemiology of melioidosis will be reviewed. PMID:16181507

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2013 CFR

2013-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2014 CFR

2014-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2011 CFR

2011-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2012 CFR

2012-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

Helminth infections predispose mice to pneumococcal pneumonia but not to other pneumonic pathogens.

PubMed

Apiwattanakul, Nopporn; Thomas, Paul G; Kuhn, Raymond E; Herbert, De'Broski R; McCullers, Jonathan A

2014-10-01

Pneumonia is the leading killer of children worldwide. Here, we report that helminth-infected mice develop fatal pneumonia when challenged with Streptococcus pneumoniae. Mice were chronically infected with either the flatworm Taenia crassiceps or the roundworm Heligmosomoides polygyrus. Upon challenge with a pneumonic type 3 strain of S. pneumoniae (A66.1), the worm-infected mice developed pneumonia at a rate and to a degree higher than age-matched control mice as measured by bioluminescent imaging and lung titers. This predisposition to pneumonia appears to be specific to S. pneumoniae, as worm-infected mice did not show evidence of increased morbidity when challenged with a lethal dose of influenza virus or sublethal doses of Staphylococcus aureus or Listeria monocytogenes. The defect was also present when worm-infected mice were challenged with a type 2 sepsis-causing strain (D39); an increased rate of pneumonia, decreased survival, and increased lung and blood titers were found. Pneumococcal colonization and immunity against acute otitis media were unaffected. Anti-helminthic treatment in the H. polygyrus model reversed this susceptibility. We conclude that helminth coinfection predisposes mice to fatal pneumococcal pneumonia by promoting increased outgrowth of bacteria in the lungs and blood. These data have broad implications for the prevention and treatment for pneumonia in the developing world, where helminth infections are endemic and pneumococcal pneumonia is common.

Role of an Iron-Dependent Transcriptional Regulator in the Pathogenesis and Host Response to Infection with Streptococcus pneumoniae

PubMed Central

Gupta, Radha; Bhatty, Minny; Swiatlo, Edwin; Nanduri, Bindu

2013-01-01

Iron is a critical cofactor for many enzymes and is known to regulate gene expression in many bacterial pathogens. Streptococcus pneumoniae normally inhabits the upper respiratory mucosa but can also invade and replicate in lungs and blood. These anatomic sites vary considerably in both the quantity and form of available iron. The genome of serotype 4 pneumococcal strain TIGR4 encodes a putative iron-dependent transcriptional regulator (IDTR). A mutant deleted at idtr (Δidtr) exhibited growth kinetics similar to parent strain TIGR4 in vitro and in mouse blood for up to 48 hours following infection. However, Δidtr was significantly attenuated in a murine model of sepsis. IDTR down-regulates the expression of ten characterized and putative virulence genes in nasopharyngeal colonization and pneumonia. The host cytokine response was significantly suppressed in sepsis with Δidtr. Since an exaggerated inflammatory response is associated with a poor prognosis in sepsis, the decreased inflammatory response could explain the increased survival with Δidtr. Our results suggest that IDTR, which is dispensable for pneumococcal growth in vitro, is associated with regulation of pneumococcal virulence in specific host environments. Additionally, IDTR ultimately modulates the host cytokine response and systemic inflammation that contributes to morbidity and mortality of invasive pneumococcal disease. PMID:23437050

Evidence that the Essential Response Regulator YycF in Streptococcus pneumoniae Modulates Expression of Fatty Acid Biosynthesis Genes and Alters Membrane Composition†

PubMed Central

Mohedano, M. Luz; Overweg, Karin; de la Fuente, Alicia; Reuter, Mark; Altabe, Silvia; Mulholland, Francis; de Mendoza, Diego; López, Paloma; Wells, Jerry M.

2005-01-01

The YycFG two-component system, originally identified in Bacillus subtilis, is highly conserved among gram-positive bacteria with low G+C contents. In Streptococcus pneumoniae, the YycF response regulator has been reported to be essential for cell growth, but the signal to which it responds and the gene members of the regulon remain unclear. In order to investigate the role of YycFG in S. pneumoniae, we increased the expression of yycF by using a maltose-inducible vector and analyzed the genome-wide effects on transcription and protein expression during the course of yycF expression. The induction of yycF expression increased histidine kinase yycG transcript levels, suggesting an autoregulation of the yycFG operon. Evidence from both proteomic and microarray transcriptome studies as well as analyses of membrane fatty acid composition indicated that YycFG is involved in the regulation of fatty acid biosynthesis pathways and in determining fatty acid chain lengths in membrane lipids. In agreement with recent transcriptome data on pneumococcal cells depleted of YycFG, we also identified several other potential members of the YycFG regulon that are required for virulence and cell wall biosynthesis and metabolism. PMID:15774879

Port d’Entrée for Respiratory Infections – Does the Influenza A Virus Pave the Way for Bacteria?

PubMed Central

Siemens, Nikolai; Oehmcke-Hecht, Sonja; Mettenleiter, Thomas C.; Kreikemeyer, Bernd; Valentin-Weigand, Peter; Hammerschmidt, Sven

2017-01-01

Bacterial and viral co-infections of the respiratory tract are life-threatening and present a global burden to the global community. Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes are frequent colonizers of the upper respiratory tract. Imbalances through acquisition of seasonal viruses, e.g., Influenza A virus, can lead to bacterial dissemination to the lower respiratory tract, which in turn can result in severe pneumonia. In this review, we summarize the current knowledge about bacterial and viral co-infections of the respiratory tract and focus on potential experimental models suitable for mimicking this disease. Transmission of IAV and pneumonia is mainly modeled by mouse infection. Few studies utilizing ferrets, rats, guinea pigs, rabbits, and non-human primates are also available. The knowledge gained from these studies led to important discoveries and advances in understanding these infectious diseases. Nevertheless, mouse and other infection models have limitations, especially in translation of the discoveries to humans. Here, we suggest the use of human engineered lung tissue, human ex vivo lung tissue, and porcine models to study respiratory co-infections, which might contribute to a greater translation of the results to humans and improve both, animal and human health. PMID:29312268

Etiology of Acute, Non-Malaria, Febrile Illnesses in Jayapura, Northeastern Papua, Indonesia

PubMed Central

Punjabi, Narain H.; Taylor, Walter R. J.; Murphy, Gerald S.; Purwaningsih, Sri; Picarima, Helena; Sisson, John; Olson, James G.; Baso, Samuel; Wangsasaputra, Ferry; Lesmana, Murad; Oyofo, Buhari A.; Simanjuntak, Cyrus H.; Subekti, Decy; Corwin, Andrew L.; Richie, Thomas L.

2012-01-01

We conducted a prospective, inpatient fever study in malaria-endemic Papua, Indonesia to determine non-malaria fever etiologies. Investigations included malaria blood films, blood culture, paired serologic samples analysis for dengue, Japanese encephalitis, leptospirosis, scrub typhus, murine typhus, and spotted fever group rickettsia. During 1997–2000, 226 patients (127 males and 99 females) 1–80 years of age (median age = 25 years) were enrolled. Positive blood cultures (n = 34, 15%) were obtained for Salmonella Typhi (n = 13), Escherichia coli (n = 8), Streptococcus pneumoniae (n = 6), Staphylococcus aureus (n = 5), Streptococcus pyogenes (n = 1), and Klebsiella pneumoniae (n = 1). Twenty (8.8%) patients were positive for leptospirosis by polymerase chain reaction. Eighty (35.4%) of 226 patients had ≥ 1 positive serology, diagnostic for 15 rickettsial and 9 dengue cases. Acid-fast bacilli–positive sputum was obtained from three patients. Most common confirmed (81 of 226, 35.8%)/suspected diagnoses were typhoid fever (n = 41), pneumonia (n = 29), leptospirosis (n = 28), urinary tract infections (n = 20), rickettsioses (n = 19), dengue (n = 17), and meningitis/encephalitis (n = 15). There were 17 deaths, 7 (46.7%) were caused by meningitis/encephalitis. Multiple positive serologic results and few confirmed diagnoses indicate the need for improved diagnostics. PMID:22232450

Unraveling the Pore-Forming Steps of Pneumolysin from Streptococcus pneumoniae.

PubMed

van Pee, Katharina; Mulvihill, Estefania; Müller, Daniel J; Yildiz, Özkan

2016-12-14

Pneumolysin (PLY) is the main virulence factor of Streptococcus pneumoniae that causes pneumonia, meningitis, and invasive pneumococcal infection. PLY is produced as monomers, which bind to cholesterol-containing membranes, where they oligomerize into large pores. To investigate the pore-forming mechanism, we determined the crystal structure of PLY at 2.4 Å and used it to design mutants on the surface of monomers. Electron microscopy of liposomes incubated with PLY mutants revealed that several mutations interfered with ring formation. Mutants that formed incomplete rings or linear arrays had strongly reduced hemolytic activity. By high-resolution time-lapse atomic force microscopy of wild-type PLY, we observed two different ring-shaped complexes. Most of the complexes protruded ∼8 nm above the membrane surface, while a smaller number protruded ∼11 nm or more. The lower complexes were identified as pores or prepores by the presence or absence of a lipid bilayer in their center. The taller complexes were side-by-side assemblies of monomers of soluble PLY that represent an early form of the prepore. Our observations suggest a four-step mechanism of membrane attachment and pore formation by PLY, which is discussed in the context of recent structural models. The functional separation of these steps is necessary for the understanding how cholesterol-dependent cytolysins form pores and lyse cells.

Novel mucosal vaccines generated by genetic conjugation of heterologous proteins to pneumolysin (PLY) from Streptococcus pneumoniae.

PubMed

Douce, Gill; Ross, Kirsty; Cowan, Graeme; Ma, Jiangtao; Mitchell, Tim J

2010-04-19

Induction of immunity at mucosal surfaces is thought to be an essential feature in the protection of the host against the many pathogens that gain access through these surfaces. Here we describe how strong local and systemic immune responses can be generated when proteins are genetically conjugated to pneumolysin (PLY) from Streptococcus pneumoniae. Using green fluorescent protein (eGFP) and PsaA from S. pneumoniae, we have shown that genetic fusion (eGFPPLY and PsaAPLY) is essential to ensure high levels of antigen specific IgG and IgA in the serum and at mucosal surfaces. This form of vaccination is highly effective with antigen specific antibodies detected after a single dose of nanogram quantities of the conjugated proteins. In addition, generation of a non-toxic variant (eGFPDelta6PLY) indicated that while the toxic activity of PLY was not essential for adjuvanticity, it contributed to the magnitude of the response generated. Whilst vaccination with the PsaAPLY fusion proteins did not protect the animals from challenge, these studies confirm the utility of pneumolysin to act as a novel mucosal adjuvant to substantially increase the local and systemic humoral response to genetically fused protein antigens. Copyright 2010 Elsevier Ltd. All rights reserved.

[Epidemio-clinical aspects of adult acute bacterial pneumonia at Yalgado Ouédraogo University Health Center].

PubMed

Ouédraogo, S M; Toloba, Y; Badoum, G; Ouédraogo, G; Boncoungou, K; Bambara, M; Ouédraogo, E W M; Zigani, A; Sangaré, L; Ouédraogo, M

2010-01-01

Bacterial Pneumopathies are low respiratory infections due to parenchyma pulmonary attack, which etiologic agent is a bacteria different from tubercular bacillus. Factually, the treatment is based on a probalistic antibiotherapy. This requires awareness of the epidemiology of the germs which are responsible in a given region, at a given period. In order to better grasp mainly the bacteriological and therapeutic aspects of adult bacterial Pneumopathies in Burkina Faso, we have come up with a two year journal/documentary. The reported most frequent germs are respectively: Streptococcus pneumoniae (32,6%), Klebsiella pneumoniae (21%) et Staphylococcus aureus (13,9%). Negative Gram bacteries represented 53.5% of isolated germ and Acinetobacter was found only with HIV positive patients. The streptococcus was sensitive to association amoxicilline + clavulanic in 91.7% of the cases, to ceftriaxone in 83.3% of cases, to ampicilline and to amoxicilline in 66.7% of cases The clinical evolution of our patients was favorable in 74.5% of the cases with 21.8% deaths. The evolution was more significant within alcoholic patients (p = 0.001) as well as tobacco addicted patients (p = 0.02). The high morbi-morbidity due to acute pneumopathy could be improved through a better awareness and regular updating of local bacterial ecology.

Altered murein composition in a DD-carboxypeptidase mutant of Streptococcus pneumoniae.

PubMed Central

Severin, A; Schuster, C; Hakenbeck, R; Tomasz, A

1992-01-01

The muropeptide composition of a Streptococcus pneumoniae mutant in which the DD-carboxypeptidase (penicillin-binding protein 3) gene was interrupted by plasmid insertion close to the 3' end of the gene was examined. Extensive compositional changes were observed: the linear pentapeptide, a minor component of the parental cells, became the most abundant monomeric peptide in the mutant wall, while the proportion of tripeptides that represent the main monomers in the parental cells was greatly reduced. The amount of the major dimer of parental cells, the directly cross-linked tri-tetrapeptide, was also reduced by a factor of 4. It was partially replaced by a novel dimer: the cross-linked product of a linear pentapeptide and a pentapeptide carrying a serylalanine dipeptide substituent on the epsilon-NH2 group of its lysine residue. This dimer together with two other dimeric peptides, each containing the serylalanine cross bridge, became the quantitatively major components of the mutant peptidoglycan. PMID:1629174

PASTA repeats of the protein kinase StkP interconnect cell constriction and separation of Streptococcus pneumoniae.

PubMed

Zucchini, Laure; Mercy, Chryslène; Garcia, Pierre Simon; Cluzel, Caroline; Gueguen-Chaignon, Virginie; Galisson, Frédéric; Freton, Céline; Guiral, Sébastien; Brochier-Armanet, Céline; Gouet, Patrice; Grangeasse, Christophe

2018-02-01

Eukaryotic-like serine/threonine kinases (eSTKs) with extracellular PASTA repeats are key membrane regulators of bacterial cell division. How PASTA repeats govern eSTK activation and function remains elusive. Using evolution- and structural-guided approaches combined with cell imaging, we disentangle the role of each PASTA repeat of the eSTK StkP from Streptococcus pneumoniae. While the three membrane-proximal PASTA repeats behave as interchangeable modules required for the activation of StkP independently of cell wall binding, they also control the septal cell wall thickness. In contrast, the fourth and membrane-distal PASTA repeat directs StkP localization at the division septum and encompasses a specific motif that is critical for final cell separation through interaction with the cell wall hydrolase LytB. We propose a model in which the extracellular four-PASTA domain of StkP plays a dual function in interconnecting the phosphorylation of StkP endogenous targets along with septal cell wall remodelling to allow cell division of the pneumococcus.

Minimization of bacterial size allows for complement evasion and is overcome by the agglutinating effect of antibody

PubMed Central

Dalia, Ankur B.; Weiser, Jeffrey N.

2011-01-01

SUMMARY The complement system, which functions by lysing pathogens directly or by promoting their uptake by phagocytes, is critical for controlling many microbial infections. Here we show that in Streptococcus pneumoniae, increasing bacterial chain length sensitizes this pathogen to complement deposition and subsequent uptake by human neutrophils. Consistent with this, we show that minimizing chain length provides wild-type bacteria with a competitive advantage in vivo in a model of systemic infection. Investigating how the host overcomes this virulence strategy, we find that antibody promotes complement-dependent opsonophagocytic killing of Streptococcus pneumoniae and lysis of Haemophilus influenzae independent of Fc-mediated effector functions. Consistent with the agglutinating effect of antibody, F(ab′)2 but not Fab could promote this effect. Therefore, increasing pathogen size, whether by natural changes in cellular morphology or via antibody-mediated agglutination, promotes complement-dependent killing. These observations have broad implications for how cell size and morphology can affect virulence among pathogenic microbes. PMID:22100164

Aggregated Antibiograms and Monitoring of Drug-Resistant Streptococcus pneumoniae

PubMed Central

Lexau, Catherine; Baughman, Wendy; Barnes, Brenda; Bennett, Nancy; Cassidy, P. Maureen; Pass, Margaret; Gelling, Lisa; Barrett, Nancy L.; Zell, Elizabeth R.; Whitney, Cynthia G.

2003-01-01

Community-specific antimicrobial susceptibility data may help monitor trends among drug-resistant Streptococcus pneumoniae and guide empiric therapy. Because active, population-based surveillance for invasive pneumococcal disease is accurate but resource intensive, we compared the proportion of penicillin-nonsusceptible isolates obtained from existing antibiograms, a less expensive system, to that obtained from 1 year of active surveillance for Georgia, Tennessee, California, Minnesota, Oregon, Maryland, Connecticut, and New York. For all sites, proportions of penicillin-nonsusceptible isolates from antibiograms were within 10 percentage points (median 3.65) of those from invasive-only isolates obtained through active surveillance. Only 23% of antibiograms distinguished between isolates intermediate and resistant to penicillin; 63% and 57% included susceptibility results for erythromycin and extended-spectrum cephalosporins, respectively. Aggregating existing hospital antibiograms is a simple and relatively accurate way to estimate local prevalence of penicillin-nonsusceptible pneumococcus; however, antibiograms offer limited data on isolates with intermediate and high-level penicillin resistance and isolates resistant to other agents. PMID:14519245

Dynamics of serotype 14 Streptococcus pneumoniae population causing acute respiratory infections among children in China (1997-2012).

PubMed

He, Mingming; Yao, Kaihu; Shi, Wei; Gao, Wei; Yuan, Lin; Yu, Sangjie; Yang, Yonghong

2015-07-11

In the last decade, the Streptococcus pneumoniae population has changed, mainly due to the abuse of antibiotics. The aim of this study was to determine the genetic structure of 144 S. pneumonia serotype 14 isolates collected from children with acute respiratory infections during 1997-2012 in China. All isolated pneumococci were tested for their sensitivity to 11 kinds of antibiotics with the E-test method or disc diffusion. The macrolides resistance genes ermB and mefA, as well as the sulfamethoxazole-trimethoprim resistance gene dihydrofolate reductase (DHFR) were detected by polymerase chain reaction (PCR). The sequence types (STs) were analyzed with multilocus sequence typing (MLST). From 1997 to 2012, the percentage of serotype 14 S. pneumonia isolates in the whole isolates increased. All of the 144 serotype 14 S. pneumonia isolates were susceptible to amoxicillin-clavulanic acid, vancomycin and levofloxacin. No penicillin resistant isolate was found, and the intermediate rate was as low as 0.7 %. Erythromycin resistance was confirmed among 143 isolates. The ermB gene was determined in all erythromycin resistant isolates, and the mefA gene was positive additionally in 13 of them. The non-susceptibility rate to the tested cephalosporins increased from 1997-2012. All trimethoprim-resistant isolates contained the Ile100-Leu mutation. Overall, 30 STs were identified, among which ST876 was the most prevalent, followed by ST875. During the study period, the percentage of CC876 increased from 0 % in 1997-2000 to 96.4 % in 2010-2012, whereas CC875 decreased from 84.2 to 0 %. CC876 showed higher non-susceptibility rates to β-lactam antibiotics than CC875. The percentage of serotype 14 S. pneumonia isolates increased over time in China. The increase of resistance to β-lactam antibiotics in this serotype isolates was associated with the spread of CC876.

Effectiveness of the standard and an alternative set of Streptococcus pneumoniae multi locus sequence typing primers.

PubMed

Adamiak, Paul; Vanderkooi, Otto G; Kellner, James D; Schryvers, Anthony B; Bettinger, Julie A; Alcantara, Joenel

2014-06-03

Multi-locus sequence typing (MLST) is a portable, broadly applicable method for classifying bacterial isolates at an intra-species level. This methodology provides clinical and scientific investigators with a standardized means of monitoring evolution within bacterial populations. MLST uses the DNA sequences from a set of genes such that each unique combination of sequences defines an isolate's sequence type. In order to reliably determine the sequence of a typing gene, matching sequence reads for both strands of the gene must be obtained. This study assesses the ability of both the standard, and an alternative set of, Streptococcus pneumoniae MLST primers to completely sequence, in both directions, the required typing alleles. The results demonstrated that for five (aroE, recP, spi, xpt, ddl) of the seven S. pneumoniae typing alleles, the standard primers were unable to obtain the complete forward and reverse sequences. This is due to the standard primers annealing too closely to the target regions, and current sequencing technology failing to sequence the bases that are too close to the primer. The alternative primer set described here, which includes a combination of primers proposed by the CDC and several designed as part of this study, addresses this limitation by annealing to highly conserved segments further from the target region. This primer set was subsequently employed to sequence type 105 S. pneumoniae isolates collected by the Canadian Immunization Monitoring Program ACTive (IMPACT) over a period of 18 years. The inability of several of the standard S. pneumoniae MLST primers to fully sequence the required region was consistently observed and is the result of a shift in sequencing technology occurring after the original primers were designed. The results presented here introduce clear documentation describing this phenomenon into the literature, and provide additional guidance, through the introduction of a widely validated set of alternative primers, to research groups seeking to undertake S. pneumoniae MLST based studies.

Structure and proposed mechanism of α-glycerophosphate oxidase from Mycoplasma pneumoniae

DOE PAGES

Elkhal, Callia K.; Kean, Kelsey M.; Parsonage, Derek; ...

2015-03-14

In this study, the formation of hydrogen peroxide (H₂O₂) by the FAD-dependent α-glycerophosphate oxidase (GlpO), is important for the pathogenesis of Streptococcus pneumoniae and Mycoplasma pneumoniae. The structurally known GlpO from Streptococcus sp. ( SspGlpO) is similar to the pneumococcal protein ( SpGlpO) and provides a guide for drug design against that target. However, M. pneumoniae GlpO ( MpGlpO), having <20% sequence identity with structurally known GlpOs, appears to represent a second type of GlpO we designate as Type II GlpOs. Here, the recombinant His-tagged MpGlpO structure is described at ~2.5 Å resolution, solved by molecular replacement using as amore » search model the Bordetella pertussis protein 3253 (Bp3253) a protein of unknown function solved by structural genomics efforts. Recombinant MpGlpO is an active oxidase with a turnover number of ~580 min⁻¹ while Bp3253 showed no GlpO activity. No substantial differences exist between the oxidized and dithionite-reduced MpGlpO structures. Although, no liganded structures were determined, a comparison with the tartrate-bound Bp3253 structure and consideration of residue conservation patterns guided the construction of a model for α-glycerophosphate (Glp) recognition and turnover by MpGlpO. The predicted binding mode also appears relevant for the type I GlpOs (such as SspGlpO) despite differences in substrate recognition residues, and it implicates a histidine conserved in type I and II Glp oxidases and dehydrogenases as the catalytic acid/base. This work provides a solid foundation for guiding further studies of the mitochondrial Glp dehydrogenases as well as for continued studies of M. pneumoniae and S. pneumoniae glycerol metabolism and the development of novel therapeutics targeting MpGlpO and SpGlpO.« less

Structure and proposed mechanism of α-glycerophosphate oxidase from Mycoplasma pneumoniae

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

Elkhal, Callia K.; Kean, Kelsey M.; Parsonage, Derek

In this study, the formation of hydrogen peroxide (H₂O₂) by the FAD-dependent α-glycerophosphate oxidase (GlpO), is important for the pathogenesis of Streptococcus pneumoniae and Mycoplasma pneumoniae. The structurally known GlpO from Streptococcus sp. ( SspGlpO) is similar to the pneumococcal protein ( SpGlpO) and provides a guide for drug design against that target. However, M. pneumoniae GlpO ( MpGlpO), having <20% sequence identity with structurally known GlpOs, appears to represent a second type of GlpO we designate as Type II GlpOs. Here, the recombinant His-tagged MpGlpO structure is described at ~2.5 Å resolution, solved by molecular replacement using as amore » search model the Bordetella pertussis protein 3253 (Bp3253) a protein of unknown function solved by structural genomics efforts. Recombinant MpGlpO is an active oxidase with a turnover number of ~580 min⁻¹ while Bp3253 showed no GlpO activity. No substantial differences exist between the oxidized and dithionite-reduced MpGlpO structures. Although, no liganded structures were determined, a comparison with the tartrate-bound Bp3253 structure and consideration of residue conservation patterns guided the construction of a model for α-glycerophosphate (Glp) recognition and turnover by MpGlpO. The predicted binding mode also appears relevant for the type I GlpOs (such as SspGlpO) despite differences in substrate recognition residues, and it implicates a histidine conserved in type I and II Glp oxidases and dehydrogenases as the catalytic acid/base. This work provides a solid foundation for guiding further studies of the mitochondrial Glp dehydrogenases as well as for continued studies of M. pneumoniae and S. pneumoniae glycerol metabolism and the development of novel therapeutics targeting MpGlpO and SpGlpO.« less

Streptococcal Diversity of Human Milk and Comparison of Different Methods for the Taxonomic Identification of Streptococci.

PubMed

Martín, Virginia; Mediano, Pilar; Del Campo, Rosa; Rodríguez, Juan M; Marín, María

2016-11-01

The genus Streptococcus is 1 of the dominant bacterial groups in human milk, but the taxonomic identification of some species remains difficult. The objective of this study was to investigate the discriminatory ability of different methods to identify streptococcal species in order to perform an assessment of the streptococcal diversity of human milk microbiota as accurately as possible. The identification of 105 streptococcal strains from human milk was performed by 16S rRNA, tuf, and sodA gene sequencing, phylogenetic analysis, and Matrix Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) mass spectrometry. Streptococcus salivarius, Streptococcus mitis, and Streptococcus parasanguinis were the streptococcal dominant species in the human milk microbiota. Sequencing of housekeeping genes allowed the classification of 96.2% (16S rRNA), 84.8% ( sodA), and 88.6% ( tuf) of the isolates. Phylogenetic analysis showed 3 main streptococcal clusters corresponding with the mitis (73 isolates), salivarius (29), mutans (1)-pyogenic (2) groups, but many of the mitis group isolates (36) could not be assigned to any species. The application of the MALDI-TOF Bruker Biotyper system resulted in the identification of 56 isolates (53.33%) at the species level, but it could not discriminate between S pneumoniae and S mitis isolates, in contrast to the Vitek-MS system. There was a good agreement among the different methods assessed in this study to identify those isolates of the salivarius, mutans, and pyogenic groups, whereas unambiguous discrimination could not be achieved concerning some species of the mitis group ( S mitis, S pneumoniae, S pseudopneumoniae, S oralis).

Treatment of experimental pneumonia due to penicillin-resistant Streptococcus pneumoniae in immunocompetent rats.

PubMed Central

Gavaldà, J; Capdevila, J A; Almirante, B; Otero, J; Ruiz, I; Laguarda, M; Allende, H; Crespo, E; Pigrau, C; Pahissa, A

1997-01-01

A model of pneumonia due to Streptococcus pneumoniae resistant to penicillin was developed in immunocompetent Wistar rats and was used to evaluate the efficacies of different doses of penicillin, cefotaxime, cefpirome, and vancomycin. Adult Wistar rats were challenged by intratracheal inoculation with 3 x 10(9) CFU of one strain of S. pneumoniae resistant to penicillin (MICs of penicillin, cefotaxime, cefpirome, and vancomycin, 2, 1, 0.5, and 0.5 microg/ml, respectively) suspended in brain heart broth supplemented with 0.7% agar. The rats experienced a fatal pneumonia, dying within 5 days and with peak mortality (70 to 80%) occurring 48 to 72 h after infection, and the bacterial counts in the lungs persisted from 8.87 +/- 0.3 log10 CFU/g of lung at 24 h of the infection to 9.1 +/- 0.3 log10 CFU/g at 72 h. Four hours after infection the animals were randomized into the following treatment groups: (i) control without treatment, (ii) penicillin G at 100,000 IU/kg of body weight every 2 h, (iii) penicillin G at 250,000 IU/kg every 2 h, (iv) cefotaxime at 100 mg/kg every 2 h, (v) cefpirome at 200 mg/kg every 2 h, and (vi) vancomycin at 50 mg/kg every 8 h. Two different protocols were used for the therapeutic efficacy studies: four doses of beta-lactams and one dose of vancomycin or eight doses of beta-lactams and two doses of vancomycin. Results of the therapy for experimental pneumonia caused by penicillin-resistant S. pneumoniae showed that initially, all the antimicrobial agents tested had similar efficacies, but when we prolonged the treatment, higher doses of penicillin, cefotaxime, and cefpirome were more effective than penicillin at lower doses in decreasing the residual bacterial titers in the lungs. Also, when we extended the treatment, vancomycin was more efficacious than penicillin at lower doses but was less efficacious than higher doses of penicillin or cefpirome. The model that we have developed is simple and amenable for inducing pneumonia in immunocompetent rats and could be used to explore the pathophysiology and to evaluate optimal therapy of this infection in the immunocompetent host. PMID:9087492

In Vitro Activities of ABT-492, a New Fluoroquinolone, against 155 Aerobic and 171 Anaerobic Pathogens Isolated from Antral Sinus Puncture Specimens from Patients with Sinusitis

PubMed Central

Goldstein, Ellie J. C.; Citron, Diane M.; Merriam, C. Vreni; Warren, Yumi A.; Tyrrell, Kerin L.; Fernandez, Helen T.

2003-01-01

ABT-492 exhibited excellent in vitro activities against all 326 aerobic and anaerobic antral puncture sinus isolates tested with MICs (in micrograms per milliliter) at which 90% of the isolates tested were inhibited as follows: Haemophilus influenzae, 0.001; Moraxella catarrhalis, 0.008; and Streptococcus pneumoniae, 0.015. It was four- to sixfold more active than other fluoroquinolones, including against levofloxacin-resistant strains of S. pneumoniae, methicillin-resistant Staphylococcus aureus, and Prevotella species. PMID:12937015

In vitro activities of ABT-492, a new fluoroquinolone, against 155 aerobic and 171 anaerobic pathogens isolated from antral sinus puncture specimens from patients with sinusitis.

PubMed

Goldstein, Ellie J C; Citron, Diane M; Merriam, C Vreni; Warren, Yumi A; Tyrrell, Kerin L; Fernandez, Helen T

2003-09-01

ABT-492 exhibited excellent in vitro activities against all 326 aerobic and anaerobic antral puncture sinus isolates tested with MICs (in micrograms per milliliter) at which 90% of the isolates tested were inhibited as follows: Haemophilus influenzae, 0.001; Moraxella catarrhalis, 0.008; and Streptococcus pneumoniae, 0.015. It was four- to sixfold more active than other fluoroquinolones, including against levofloxacin-resistant strains of S. pneumoniae, methicillin-resistant Staphylococcus aureus, and Prevotella species.

Legionnaire's disease during pregnancy: a case presentation and review of the literature.

PubMed

Eisenberg, V H; Eidelman, L A; Arbel, R; Ezra, Y

1997-03-01

Acute pneumonia complicating pregnancy can have serious consequences for both the mother and the fetus. Streptococcus pneumoniae remains the most common bacterial pathogen, but Legionella pneumophila must be considered as well, especially in severe multisystem disease. With severe disease, premature delivery may occur as has been described in the only previous report of Legionnaire's disease during pregnancy. We present here the first report of Legionnaire's disease in pregnancy, resulting in the term delivery of a healthy infant. Also presented is an extensive review of the literature.

Identification of a Secreted Cholesterol-Dependent Cytolysin (Mitilysin) from Streptococcus mitis▿

PubMed Central

Jefferies, Johanna; Nieminen, Leena; Kirkham, Lea-Ann; Johnston, Calum; Smith, Andrew; Mitchell, Tim J.

2007-01-01

We have detected a cholesterol-dependent cytolysin, which we have named mitilysin, in a small number of Streptococcus mitis isolates. We have sequenced the mitilysin gene from seven isolates of S. mitis. Comparisons with the pneumococcal pneumolysin gene show 15 amino acid substitutions. S. mitis appear to release mitilysin extracellularly. Certain alleles of mitilysin are not recognized by a monoclonal antibody raised to the related toxin pneumolysin. Based on enzyme-linked immunosorbent assay and neutralization assay results, one isolate of S. mitis may produce a further hemolytic toxin in addition to mitilysin. As genetic exchange is known to occur between S. mitis and Streptococcus pneumoniae, this finding may have implications for the development of vaccines or therapies for pneumococcal disease that are based on pneumolysin. PMID:17071760

Future challenges in the elimination of bacterial meningitis.

PubMed

Bottomley, Matthew J; Serruto, Davide; Sáfadi, Marco Aurélio Palazzi; Klugman, Keith P

2012-05-30

Despite the widespread implementation of several effective vaccines over the past few decades, bacterial meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis and Group B Streptococcus (GBS) still results in unacceptably high levels of human mortality and morbidity. A residual disease burden due to bacterial meningitis is also apparent due to a number of persistent or emerging pathogens, including Mycobacterium tuberculosis, Escherichia coli, Staphylococcus aureus, Salmonella spp. and Streptococcus suis. Here, we review the current status of bacterial meningitis caused by these pathogens, highlighting how past and present vaccination programs have attempted to counter these pathogens. We discuss how improved pathogen surveillance, implementation of current vaccines, and development of novel vaccines may be expected to further reduce bacterial meningitis and related diseases in the future. Copyright © 2011 Elsevier Ltd. All rights reserved.

Antibacterial activity of cinnamon ethanol extract (cinnamomum burmannii) and its application as a mouthwash to inhibit streptococcus growth

NASA Astrophysics Data System (ADS)

Waty, Syahdiana; Suryanto, Dwi; Yurnaliza

2018-03-01

Cinnamon bark has been commonly used as spicy and traditional medicine. It contains several antibacterial compounds such as flavonoids, saponins, and cinnamaldehyde. Several studies have been done to know the antibacterial effect on bacteria such as Streptococcus in vitro. This study aimed to examine the antibacterial activity of cinnamon ethanol extract against Streptococcus and its application as mouthwash to inhibit the bacteria. The cinnamon bark was macerated followed by extracted in 80% ethanol. Bacterial samples were isolated from dental plaque of patients visiting dental clinic drg. Syahdiana Waty in Medan, North Sumatra. The isolates were identified using Vitek 2 compact. Secondary metabolites were detected using previously described method. Antibacterial assay was done at extract concentration of 6.25%, 12.5%, and 25%. The result showed that alkaloids, flavonoids, saponins, and glycoside were detected in the extract. Nine bacterial species were identified as Streptococcus mitis, S. sanguinis, S. salivarius, S. pluranimalium, S. pneumoniae, S. alactolyticus, Kocuria rosea, Kocuria kristinae, and Spingomonas paucimolis. It showed that the extract of Cinnamon bark significantly inhibited Streptococcus growth, and it was effective as mouthwash.

62 FR 6261 - Determination of Regulatory Review Period for Purposes of Patent Extension; MERREMRegister I.V.

Federal Register 2010, 2011, 2012, 2013, 2014

1997-02-11

...): Bacterial meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae ( -lactamase and non.... (meropenem). MERREM I.V. is indicated as single agent therapy for the treatment of the following infections...-abdominal Infections: Complicated appendicitis and peritonitis caused by viridans group streptococci...

Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae.

PubMed

Maricic, Natalie; Anderson, Erica S; Opipari, AnneMarie E; Yu, Emily A; Dawid, Suzanne

2016-01-26

Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus) in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials. Successful colonization of a polymicrobial host surface is a prerequisite for the subsequent development of disease for many bacterial pathogens. Bacterial factors that directly inhibit the growth of neighbors may provide an advantage during colonization if the inhibition of competitors outweighs the energy for production. In this work, we found that production of a potent antimicrobial called pneumolancidin conferred a competitive advantage to the pathogen Streptococcus pneumoniae. S. pneumoniae secreting pneumolancidin inhibits a wide array of Gram-positive organisms, including all but one tested pneumococcal strain. The pneumolancidin genetic locus is of particular interest because it encodes three similar modified peptides (lantibiotics), each of which has a distinct role in the function of the locus. Lantibiotics represent a relatively untapped resource for the development of clinically useful antibiotics which are desperately needed. The broad inhibitory activity of pneumolancidin makes it an ideal candidate for further characterization and development. Copyright © 2016 Maricic et al.

PDI using nebulized indocyanine green for pneumonia treatment

NASA Astrophysics Data System (ADS)

Geralde, Mariana C.; Kassab, Giulia; Inada, Natalia M.; Kurachi, Cristina; Bagnato, Vanderlei S.

2018-02-01

Infectious pneumonia is a major cause of morbidity/mortality, mainly due to the increasing rate of microorganisms resistant to antibiotics. Photodynamic Inactivation (PDI) is emerging as a promising treatment option, which effects are based on oxidative stress, targeting several biomolecules and probably preventing potential resistant strains. In previous studies, the in vitro inactivation of Streptococcus pneumoniae using indocyanine green (ICG) and infrared (IR) light source (780 nm) was successful, and achieving satisfactory reduction of colony-forming units (CFU/mL). In the present study, a proof-of-principle protocol was designed to treat lung infections by PDI using extracorporeal irradiation with a 780 nm laser device and nebulized ICG as photosensitizer. Balb/c mice were infected with S. pneumoniae and PDI was performed two days after infection using 800 μM of nebulized ICG and extracorporeal irradiation. Our results indicate that IR-extracorporeal PDI using nebulized ICG may be considered a potential pneumonia treatment, and pulmonary decontamination with PDI may be used as a single therapy or as an adjuvant for antibiotics.

Influence of bacterial interactions on pneumococcal colonization of the nasopharynx.

PubMed

Shak, Joshua R; Vidal, Jorge E; Klugman, Keith P

2013-03-01

Streptococcus pneumoniae (the pneumococcus) is a common commensal inhabitant of the nasopharynx and a frequent etiologic agent in serious diseases such as pneumonia, otitis media, bacteremia, and meningitis. Multiple pneumococcal strains can colonize the nasopharynx, which is also home to many other bacterial species. Intraspecies and interspecies interactions influence pneumococcal carriage in important ways. Co-colonization by two or more pneumococcal strains has implications for vaccine serotype replacement, carriage detection, and pneumonia diagnostics. Interactions between the pneumococcus and other bacterial species alter carriage prevalence, modulate virulence, and affect biofilm formation. By examining these interactions, this review highlights how the bacterial ecosystem of the nasopharynx changes the nature and course of pneumococcal carriage. Copyright © 2012 Elsevier Ltd. All rights reserved.

Epidemiology of Otitis Media with Spontaneous Perforation of the Tympanic Membrane in Young Children and Association with Bacterial Nasopharyngeal Carriage, Recurrences and Pneumococcal Vaccination in Catalonia, Spain - The Prospective HERMES Study.

PubMed

Cilveti, Robert; Olmo, Montserrat; Pérez-Jove, Josefa; Picazo, Juan-José; Arimany, Josep-Lluis; Mora, Emiliano; Pérez-Porcuna, Tomás M; Aguilar, Ignacio; Alonso, Aurora; Molina, Francesc; Del Amo, María; Mendez, Cristina

2017-01-01

The Epidemiology of otitis media with spontaneous perforation of the tympanic membrane and associated nasopharyngeal carriage of bacterial otopathogens was analysed in a county in Catalonia (Spain) with pneumococcal conjugate vaccines (PCVs) not included in the immunization programme at study time. A prospective, multicentre study was performed in 10 primary care centres and 2 hospitals (June 2011-June 2014), including all otherwise healthy children ≥2 months ≤8 years with otitis media presenting spontaneous tympanic perforation within 48h. Up to 521 otitis episodes in 487 children were included, showing by culture/PCR in middle ear fluid (MEF): Haemophilus influenzae [24.2%], both Streptococcus pneumoniae and H. influenzae [24.0%], S. pneumoniae [15.9%], Streptococcus pyogenes [13.6%], and Staphylococcus aureus [6.7%]. Culture-negative/PCR-positive otitis accounted for 31.3% (S. pneumoniae), 30.2% (H. influenzae) and 89.6% (mixed S. pneumoniae/H. influenzae infections). Overall, incidence decreased over the 3-year study period, with significant decreases in otitis by S. pneumoniae and by H. influenzae, but no decreases for mixed S. pneumoniae/H. influenzae infections. Concordance between species in nasopharynx and MEF was found in 58.3% of cases, with maximal rates for S. pyogenes (71.8%), and with identical pneumococcal serotype in 40.5% of cases. Most patients (66.6%) had past episodes. PCV13 serotypes were significantly more frequent in first episodes, in otitis by S. pneumoniae as single agent, and among MEF than nasopharyngeal isolates. All non-PCV13 serotypes separately accounted for <5% in MEF. Up to 73.9% children had received ≥1 dose of PCV, with lower carriage of PCV13 serotypes than among non-vaccinated children. Pooling pneumococcal isolates from MEF and nasopharynx, 30% were multidrug resistant, primarily belonging to serotypes 19A [29.8%], 24A [14.3%], 19F [8.3%] and 15A [6.0%]. Our results suggest that increasing PCV13 vaccination would further reduce transmission of PCV13 serotypes with special benefits for youngest children (with none or uncompleted vaccine schedules), preventing first otitis episodes and subsequent recurrences.

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.

Solithromycin for the treatment of community-acquired bacterial pneumonia.

PubMed

Viasus, Diego; Ramos, Oscar; Ramos, Leidy; Simonetti, Antonella F; Carratalà, Jordi

2017-01-01

Community-acquired pneumonia is a major public health problem worldwide. In recent years, there has been an increase in the frequency of resistance to the antimicrobials such as β-lactams or macrolides which have habitually been used against the causative pathogens. Solithromycin, a next-generation macrolide, is the first fluoroketolide with activity against most of the frequently isolated bacteria in community-acquired pneumonia, including typical and atypical bacteria as well as macrolide-resistant Streptococcus pneumoniae. Areas covered: A detailed assessment of the literature relating to the antimicrobial activity, pharmacokinetic/pharmacodynamic properties, efficacy, tolerability and safety of solithromycin for the treatment of community-acquired bacterial pneumonia Expert commentary: Recent randomized controlled phase II/III trials have demonstrated the equivalent efficacy of oral and intravenous solithromycin compared with fluoroquinolones in patients with lower mild-to-moderate respiratory infections, and have shown that systemic adverse events are comparable between solithromycin and alternative treatments. However, studies of larger populations which are able to identify infrequent adverse events are now needed to confirm these findings. On balance, current data supports solithromycin as a promising therapy for empirical treatment in adults with community-acquired bacterial pneumonia.

Pore-forming toxin-mediated ion dysregulation leads to death receptor-independent necroptosis of lung epithelial cells during bacterial pneumonia

PubMed Central

González-Juarbe, Norberto; Bradley, Kelley Margaret; Shenoy, Anukul Taranath; Gilley, Ryan Paul; Reyes, Luis Felipe; Hinojosa, Cecilia Anahí; Restrepo, Marcos Ignacio; Dube, Peter Herman; Bergman, Molly Ann; Orihuela, Carlos Javier

2017-01-01

We report that pore-forming toxins (PFTs) induce respiratory epithelial cell necroptosis independently of death receptor signaling during bacterial pneumonia. Instead, necroptosis was activated as a result of ion dysregulation arising from membrane permeabilization. PFT-induced necroptosis required RIP1, RIP3 and MLKL, and could be induced in the absence or inhibition of TNFR1, TNFR2 and TLR4 signaling. We detected activated MLKL in the lungs from mice and nonhuman primates experiencing Serratia marcescens and Streptococcus pneumoniae pneumonia, respectively. We subsequently identified calcium influx and potassium efflux as the key initiating signals responsible for necroptosis; also that mitochondrial damage was not required for necroptosis activation but was exacerbated by MLKL activation. PFT-induced necroptosis in respiratory epithelial cells did not involve CamKII or reactive oxygen species. KO mice deficient in MLKL or RIP3 had increased survival and reduced pulmonary injury during S. marcescens pneumonia. Our results establish necroptosis as a major cell death pathway active during bacterial pneumonia and that necroptosis can occur without death receptor signaling. PMID:28387756

Pore-forming toxin-mediated ion dysregulation leads to death receptor-independent necroptosis of lung epithelial cells during bacterial pneumonia.

PubMed

González-Juarbe, Norberto; Bradley, Kelley Margaret; Shenoy, Anukul Taranath; Gilley, Ryan Paul; Reyes, Luis Felipe; Hinojosa, Cecilia Anahí; Restrepo, Marcos Ignacio; Dube, Peter Herman; Bergman, Molly Ann; Orihuela, Carlos Javier

2017-05-01

We report that pore-forming toxins (PFTs) induce respiratory epithelial cell necroptosis independently of death receptor signaling during bacterial pneumonia. Instead, necroptosis was activated as a result of ion dysregulation arising from membrane permeabilization. PFT-induced necroptosis required RIP1, RIP3 and MLKL, and could be induced in the absence or inhibition of TNFR1, TNFR2 and TLR4 signaling. We detected activated MLKL in the lungs from mice and nonhuman primates experiencing Serratia marcescens and Streptococcus pneumoniae pneumonia, respectively. We subsequently identified calcium influx and potassium efflux as the key initiating signals responsible for necroptosis; also that mitochondrial damage was not required for necroptosis activation but was exacerbated by MLKL activation. PFT-induced necroptosis in respiratory epithelial cells did not involve CamKII or reactive oxygen species. KO mice deficient in MLKL or RIP3 had increased survival and reduced pulmonary injury during S. marcescens pneumonia. Our results establish necroptosis as a major cell death pathway active during bacterial pneumonia and that necroptosis can occur without death receptor signaling.

In Vitro Activity of the Novel Lactone Ketolide Nafithromycin (WCK 4873) against Contemporary Clinical Bacteria from a Global Surveillance Program.

PubMed

Flamm, R K; Rhomberg, P R; Sader, H S

2017-12-01

Nafithromycin (WCK 4873), a novel antimicrobial agent of the lactone ketolide class, is currently in phase 2 development for treatment of community-acquired bacterial pneumonia (CABP). A total of 4,739 nonduplicate isolates were selected from a 2014 global surveillance program at medical institutions located in 43 countries within the United States, Europe, Latin America, and the Asia-Pacific region. Nafithromycin and comparator agents were used for susceptibility testing by reference broth microdilution methods. Nafithromycin was active against Staphylococcus aureus (MIC 50/90 , 0.06/>2 μg/ml), including erythromycin-resistant strains exhibiting an inducible clindamycin resistance phenotype (MIC 50/90 , 0.06/0.06 μg/ml) and telithromycin-susceptible strains (MIC 50/90 , 0.06/0.06 μg/ml), but it exhibited limited activity against most telithromycin-resistant and clindamycin-resistant isolates that were constitutively resistant to macrolides (MIC 50/90 , >2/>2 μg/ml). Nafithromycin was very active (MIC 50/90 , 0.015/0.06 μg/ml) against 1,911 Streptococcus pneumoniae strains, inhibiting all strains, with MIC values of ≤0.25 μg/ml. Telithromycin susceptibility was 99.9% for Streptococcus pneumoniae strains, and nafithromycin was up to 8-fold more potent than telithromycin. Overall, 37.9% of S. pneumoniae strains were resistant to erythromycin, and 19.7% were resistant to clindamycin. Nafithromycin was highly active against 606 Streptococcus pyogenes strains (MIC 50/90 , 0.015/0.015 μg/ml), inhibiting 100.0% of isolates at ≤0.5 μg/ml, and MIC 50/90 values (0.015/0.015 to 0.03 μg/ml) were similar for the 4 geographic regions. Nafithromycin and telithromycin demonstrated comparable in vitro activities against 1,002 Haemophilus influenzae isolates and 504 Moraxella catarrhalis isolates. Overall, nafithromycin showed potent in vitro activity against a broad range of contemporary (2014) global pathogens. These results support the continued clinical development of nafithromycin for treatment of CABP. Copyright © 2017 American Society for Microbiology.

Pediatric bacterial meningitis in Japan, 2013-2015 - 3-5 years after the wide use of Haemophilus influenzae type b and Streptococcus pneumoniae conjugated vaccines.

PubMed

Shinjoh, Masayoshi; Yamaguchi, Yoshio; Iwata, Satoshi

2017-07-01

Haemophilus influenzae type b (Hib) vaccine and pneumococcal conjugated vaccine (PCV) have been widely used since 2010 in Japan when both vaccines were supported by the regional governments, and they were covered as routine recommended vaccines in 2013. The incidence of bacterial meningitis due to these organisms decreased in 2011 and 2012, but meningitis due to Streptococcus agalactiae and Escherichia coli remained unchanged. We planned to confirm whether the incidence also decreased in subsequent years. We analyzed the epidemiological and clinical data for 2013-2015, and compared the information obtained in the previous nationwide survey database and our previous reports. We also investigated the risk factors for disease outcome. In the 2013-2015 surveys, 407 patients from 366 hospitals from all prefectures were evaluated. S. agalactiae (33%), Streptococcus pneumoniae (25%), and E. coli (10%) were the main organisms. The total number of patients hospitalized with bacterial meningitis per 1000 admissions decreased from 1.19 in 2009-2010 to 0.37 in 2013-2015 (p < 0.001). The incidence of H. influenzae and S. pneumoniae meningitis significantly decreased from 0.66 in 2009-2010 to 0.01 in 2013-2015, and from 0.30 to 0.09, respectively (p < 0.001). Only 0-2 cases with Neisseria meningitidis were reported each year throughout 2001-2015. The fatality rates for H. influenzae, S. pneumoniae, S. agalactiae, and E. coli in 2013-2015 were 0.0, 4.1, 3.1, and 2.6%, respectively. Risk factors for death and sequelae were consciousness disturbance, convulsion, low CSF glucose, and Staphylococcus sp. as a causative organism (p < 0.01). Hib vaccine and PCV have decreased the rate of bacterial meningitis. S. agalactiae has subsequently become the most common cause of bacterial meningitis in Japan. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Vaccines to prevent pneumonia in children - a developing country perspective.

PubMed

Oliwa, Jacquie N; Marais, Ben J

2017-03-01

Pneumonia accounted for 15% of the 6.3 million deaths among children younger than five years in 2013, a total of approximately 935,000 deaths worldwide. Routine vaccination against common childhood illnesses has been identified as one of the most cost-effective strategies to prevent death from pneumonia. Vaccine-preventable or potentially preventable diseases commonly linked with respiratory tract infections include Streptococcus pneumoniae, Haemophilus influenza type-b (Hib), pertussis, influenza, measles, and tuberculosis. Although here have been great strides in the development and administration of effective vaccines, the countries that carry the largest disease burdens still struggle to vaccinate their children and newer conjugated vaccines remain out of reach for many. The Global Vaccine Action Plan (GVAP) has identified priority areas for innovation in research in all aspects of immunisation development and delivery to ensure equitable access to vaccines for all. Copyright © 2015 Elsevier Ltd. All rights reserved.

In Vitro Pharmacodynamic Activities of ABT-492, a Novel Quinolone, Compared to Those of Levofloxacin against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis

PubMed Central

Gunderson, Shana M.; Hayes, Robert A.; Quinn, John P.; Danziger, Larry H.

2004-01-01

ABT-492 is a novel quinolone with potent activity against gram-positive, gram-negative, and atypical pathogens, making this compound an ideal candidate for the treatment of community-acquired pneumonia. We therefore compared the in vitro pharmacodynamic activity of ABT-492 to that of levofloxacin, an antibiotic commonly used for the treatment of pneumonia, through MIC determination and time-kill kinetic analysis. ABT-492 demonstrated potent activity against penicillin-sensitive, penicillin-resistant, and levofloxacin-resistant Streptococcus pneumoniae strains (MICs ranging from 0.0078 to 0.125 μg/ml); β-lactamase-positive and β-lactamase-negative Haemophilus influenzae strains (MICs ranging from 0.000313 to 0.00125 μg/ml); and β-lactamase-positive and β-lactamase-negative Moraxella catarrhalis strains (MICs ranging from 0.001 to 0.0025 μg/ml), with MICs being much lower than those of levofloxacin. Both ABT-492 and levofloxacin demonstrated concentration-dependent bactericidal activities in time-kill kinetics studies at four and eight times the MIC with 10 of 12 bacterial isolates exposed to ABT-492 and with 12 of 12 bacterial isolates exposed to levofloxacin. Sigmoidal maximal-effect models support concentration-dependent bactericidal activity. The model predicts that 50% of maximal activity can be achieved with concentrations ranging from one to two times the MIC for both ABT-492 and levofloxacin and that near-maximal activity (90% effective concentration) can be achieved at concentrations ranging from two to five times the MIC for ABT-492 and one to six times the MIC for levofloxacin. PMID:14693540

In vitro pharmacodynamic activities of ABT-492, a novel quinolone, compared to those of levofloxacin against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

PubMed

Gunderson, Shana M; Hayes, Robert A; Quinn, John P; Danziger, Larry H

2004-01-01

ABT-492 is a novel quinolone with potent activity against gram-positive, gram-negative, and atypical pathogens, making this compound an ideal candidate for the treatment of community-acquired pneumonia. We therefore compared the in vitro pharmacodynamic activity of ABT-492 to that of levofloxacin, an antibiotic commonly used for the treatment of pneumonia, through MIC determination and time-kill kinetic analysis. ABT-492 demonstrated potent activity against penicillin-sensitive, penicillin-resistant, and levofloxacin-resistant Streptococcus pneumoniae strains (MICs ranging from 0.0078 to 0.125 micro g/ml); beta-lactamase-positive and beta-lactamase-negative Haemophilus influenzae strains (MICs ranging from 0.000313 to 0.00125 micro g/ml); and beta-lactamase-positive and beta-lactamase-negative Moraxella catarrhalis strains (MICs ranging from 0.001 to 0.0025 micro g/ml), with MICs being much lower than those of levofloxacin. Both ABT-492 and levofloxacin demonstrated concentration-dependent bactericidal activities in time-kill kinetics studies at four and eight times the MIC with 10 of 12 bacterial isolates exposed to ABT-492 and with 12 of 12 bacterial isolates exposed to levofloxacin. Sigmoidal maximal-effect models support concentration-dependent bactericidal activity. The model predicts that 50% of maximal activity can be achieved with concentrations ranging from one to two times the MIC for both ABT-492 and levofloxacin and that near-maximal activity (90% effective concentration) can be achieved at concentrations ranging from two to five times the MIC for ABT-492 and one to six times the MIC for levofloxacin.

Etiologic Agents of Central Nervous System Infections among Febrile Hospitalized Patients in the Country of Georgia

PubMed Central

Akhvlediani, Tamar; Bautista, Christian T.; Shakarishvili, Roman; Tsertsvadze, Tengiz; Imnadze, Paata; Tatishvili, Nana; Davitashvili, Tamar; Samkharadze, Tamar; Chlikadze, Rusudan; Dvali, Natia; Dzigua, Lela; Karchava, Mariam; Gatserelia, Lana; Macharashvili, Nino; Kvirkvelia, Nana; Habashy, Engy Emil; Farrell, Margaret; Rowlinson, Emily; Sejvar, James; Hepburn, Matthew; Pimentel, Guillermo; Dueger, Erica; House, Brent; Rivard, Robert

2014-01-01

Objectives There is a large spectrum of viral, bacterial, fungal, and prion pathogens that cause central nervous system (CNS) infections. As such, identification of the etiological agent requires multiple laboratory tests and accurate diagnosis requires clinical and epidemiological information. This hospital-based study aimed to determine the main causes of acute meningitis and encephalitis and enhance laboratory capacity for CNS infection diagnosis. Methods Children and adults patients clinically diagnosed with meningitis or encephalitis were enrolled at four reference health centers. Cerebrospinal fluid (CSF) was collected for bacterial culture, and in-house and multiplex RT-PCR testing was conducted for herpes simplex virus (HSV) types 1 and 2, mumps virus, enterovirus, varicella zoster virus (VZV), Streptococcus pneumoniae, HiB and Neisseria meningitidis. Results Out of 140 enrolled patients, the mean age was 23.9 years, and 58% were children. Bacterial or viral etiologies were determined in 51% of patients. Five Streptococcus pneumoniae cultures were isolated from CSF. Based on in-house PCR analysis, 25 patients were positive for S. pneumoniae, 6 for N. meningitidis, and 1 for H. influenzae. Viral multiplex PCR identified infections with enterovirus (n = 26), VZV (n = 4), and HSV-1 (n = 2). No patient was positive for mumps or HSV-2. Conclusions Study findings indicate that S. pneumoniae and enteroviruses are the main etiologies in this patient cohort. The utility of molecular diagnostics for pathogen identification combined with the knowledge provided by the investigation may improve health outcomes of CNS infection cases in Georgia. PMID:25369023

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2012: General view of the pathogens' antibacterial susceptibility.

PubMed

Yanagihara, Katsunori; Watanabe, Akira; Aoki, Nobuki; Matsumoto, Tetsuya; Yoshida, Masaki; Sato, Junko; Wakamura, Tomotaro; Sunakawa, Keisuke; Kadota, Junichi; Kiyota, Hiroshi; Iwata, Satoshi; Kaku, Mitsuo; Hanaki, Hideaki; Ohsaki, Yoshinobu; Fujiuchi, Satoru; Takahashi, Manabu; Takeuchi, Kenichi; Takeda, Hiroaki; Ikeda, Hideki; Miki, Makoto; Nakanowatari, Susumu; Takahashi, Hiroshi; Utagawa, Mutsuko; Nishiya, Hajime; Kawakami, Sayoko; Morino, Eriko; Takasaki, Jin; Mezaki, Kazuhisa; Chonabayashi, Naohiko; Tanaka, Chie; Sugiura, Hideko; Goto, Hajime; Saraya, Takeshi; Kurai, Daisuke; Katono, Yasuhiro; Inose, Rika; Niki, Yoshihito; Takuma, Takahiro; Kudo, Makoto; Ehara, Shigeru; Sato, Yoshimi; Tsukada, Hiroki; Watabe, Nobuei; Honma, Yasuo; Mikamo, Hiroshige; Yamagishi, Yuka; Nakamura, Atsushi; Ohashi, Minoru; Seki, Masafumi; Hamaguchi, Shigeto; Toyokawa, Masahiro; Fujikawa, Yasunori; Mitsuno, Noriko; Ukimura, Akira; Miyara, Takayuki; Nakamura, Takahito; Mikasa, Keiichi; Kasahara, Kei; Ui, Koji; Fukuda, Saori; Nakamura, Akihiro; Morimura, Mika; Yamashita, Mikio; Takesue, Yoshio; Wada, Yasunao; Sugimoto, Keisuke; Kusano, Nobuchika; Nose, Motoko; Mihara, Eiichirou; Kuwabara, Masao; Doi, Masao; Watanabe, Yaeko; Tokuyasu, Hirokazu; Hino, Satoshi; Negayama, Kiyoshi; Mukae, Hiroshi; Kawanami, Toshinori; Ota, Toshiyuki; Fujita, Masaki; Honda, Junichi; Hiramatsu, Kazufumi; Aoki, Yosuke; Fukuoka, Mami; Magarifuchi, Hiroki; Nagasawa, Zenzo; Kaku, Norihito; Fujita, Jiro; Higa, Futoshi; Tateyama, Masao

2017-09-01

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, Japanese association for infectious diseases and Japanese society for Clinical Microbiology in 2012. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January and December in 2012 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standard Institutes. Susceptibility testing was evaluated in 1236 strains (232 Staphylococcus aureus, 225 Streptococcus pneumoniae, 16 Streptococcus pyogenes, 231 Haemophilus influenzae, 147 Moraxella catarrhalis, 167 Klebsiella pneumoniae and 218 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 51.3%, and those of penicillin-intermediate S. pneumoniae was 0.4%. Among H. influenzae, 5.6% of them were found to be β-lactamase-producing ampicillin-resistant strains, and 37.2% to be β-lactamase-non-producing ampicillin-resistant strains. Extended spectrum β-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo β-lactamase were 4.2% and 3.2%, respectively. Continuous national surveillance is important to determine the actual situation of the resistance shown by bacterial respiratory pathogens to antimicrobial agents. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

[Macrolide-resistant Streptococcus pneumoniae on the islands of Gran Canaria and Lanzarote (Spain): molecular mechanisms and serogroup relationships].

PubMed

Artiles, Fernando; Horcajada-Herrera, Iballa; Noguera-Catalán, Javier; Alamo-Antúnez, Isabel; Bordes-Benítez, Ana; Lafarga-Capuz, Bernardo

2007-11-01

Macrolide resistance in Streptococcus pneumoniae is coded by the ermB and mefA/E genes. The aim of this study was to determine the status of macrolide-resistance, the molecular mechanisms involved, the serogroup relationships, and the level of co-resistance in S. pneumoniae isolates from Gran Canaria and Lanzarote, in the Canary Islands, Spain. Macrolide resistance phenotypes were investigated in 261 S. pneumoniae clinical isolates over a two-year period (2004 and 2005). Genotypes were determined by PCR (detection of ermB and mefA/E genes). Overall macrolide resistance was 40.6% (106 isolates); 79.2% (84) of resistant isolates presented the MLSB phenotype (98.8% harbored the ermB gene), with a predominance of serogroup 19, and 20.8% (22) presented the M phenotype (77.3% displayed the mefA/E gene), all associated with serogroup 14. Worthy of note, the M phenotype was found in 8 invasive isolates from Lanzarote (80%) all from serogroup 14. The ermB and mefA/E genes were detected in 7 isolates belonging to serogroup 19. Absence of co-resistance was observed most frequently in serogroup 14 (66.7%). Co-resistance with penicillin G, tetracycline, and trimethoprim-sulfamethoxazole was associated with serogroup 19 (36.8%). Two isolates (0.8%) were resistant to telithromycin. The frequency of macrolide resistance mechanisms in the Canary Islands is different from that observed in the rest of Spain, particularly in Lanzarote, where 80% of isolates harbored the mefA/E gene and belonged to serogroup 14.

Changing Trends in Antimicrobial Resistance and Serotypes of Streptococcus pneumoniae Isolates in Asian Countries: an Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study

PubMed Central

Kim, So Hyun; Chung, Doo Ryeon; Thamlikitkul, Visanu; Yang, Yonghong; Wang, Hui; Lu, Min; So, Thomas Man-kit; Hsueh, Po-Ren; Yasin, Rohani M.; Carlos, Celia C.; Pham, Hung Van; Lalitha, M. K.; Shimono, Nobuyuki; Perera, Jennifer; Shibl, Atef M.; Baek, Jin Yang; Kang, Cheol-In; Ko, Kwan Soo; Peck, Kyong Ran

2012-01-01

Antimicrobial resistance in Streptococcus pneumoniae remains a serious concern worldwide, particularly in Asian countries, despite the introduction of heptavalent pneumococcal conjugate vaccine (PCV7). The Asian Network for Surveillance of Resistant Pathogens (ANSORP) performed a prospective surveillance study of 2,184 S. pneumoniae isolates collected from patients with pneumococcal infections from 60 hospitals in 11 Asian countries from 2008 to 2009. Among nonmeningeal isolates, the prevalence rate of penicillin-nonsusceptible pneumococci (MIC, ≥4 μg/ml) was 4.6% and penicillin resistance (MIC, ≥8 μg/ml) was extremely rare (0.7%). Resistance to erythromycin was very prevalent in the region (72.7%); the highest rates were in China (96.4%), Taiwan (84.9%), and Vietnam (80.7%). Multidrug resistance (MDR) was observed in 59.3% of isolates from Asian countries. Major serotypes were 19F (23.5%), 23F (10.0%), 19A (8.2%), 14 (7.3%), and 6B (7.3%). Overall, 52.5% of isolates showed PCV7 serotypes, ranging from 16.1% in Philippines to 75.1% in Vietnam. Serotypes 19A (8.2%), 3 (6.2%), and 6A (4.2%) were the most prominent non-PCV7 serotypes in the Asian region. Among isolates with serotype 19A, 86.0% and 79.8% showed erythromycin resistance and MDR, respectively. The most remarkable findings about the epidemiology of S. pneumoniae in Asian countries after the introduction of PCV7 were the high prevalence of macrolide resistance and MDR and distinctive increases in serotype 19A. PMID:22232285

Repeated extragenic sequences in prokaryotic genomes: a proposal for the origin and dynamics of the RUP element in Streptococcus pneumoniae.

PubMed

Oggioni, M R; Claverys, J P

1999-10-01

A survey of all Streptococcus pneumoniae GenBank/EMBL DNA sequence entries and of the public domain sequence (representing more than 90% of the genome) of an S. pneumoniae type 4 strain allowed identification of 108 copies of a 107-bp-long highly repeated intergenic element called RUP (for repeat unit of pneumococcus). Several features of the element, revealed in this study, led to the proposal that RUP is an insertion sequence (IS)-derivative that could still be mobile. Among these features are: (1) a highly significant homology between the terminal inverted repeats (IRs) of RUPs and of IS630-Spn1, a new putative IS of S. pneumoniae; and (2) insertion at a TA dinucleotide, a characteristic target of several members of the IS630 family. Trans-mobilization of RUP is therefore proposed to be mediated by the transposase of IS630-Spn1. To account for the observation that RUPs are distributed among four subtypes which exhibit different degrees of sequence homogeneity, a scenario is invoked based on successive stages of RUP mobility and non-mobility, depending on whether an active transposase is present or absent. In the latter situation, an active transposase could be reintroduced into the species through natural transformation. Examination of sequences flanking RUP revealed a preferential association with ISs. It also provided evidence that RUPs promote sequence rearrangements, thereby contributing to genome flexibility. The possibility that RUP preferentially targets transforming DNA of foreign origin and subsequently favours disruption/rearrangement of exogenous sequences is discussed.

Bacteriological Efficacies of Three Macrolides Compared with Those of Amoxicillin-Clavulanate against Streptococcus pneumoniae and Haemophilus influenzae

PubMed Central

Berry, Valerie; Thorburn, Christine E.; Knott, Sarah J.; Woodnutt, Gary

1998-01-01

Comparative antibacterial efficacies of erythromycin, clarithromycin, and azithromycin were examined against Streptococcus pneumoniae and Haemophilus influenzae, with amoxicillin-clavulanate used as the active control. In vitro, the macrolides at twice their MICs and at concentrations achieved in humans were bacteriostatic or reduced the numbers of viable S. pneumoniae slowly, whereas amoxicillin-clavulanate showed a rapid antibacterial effect. Against H. influenzae, erythromycin, clarithromycin, and clarithromycin plus 14-hydroxy clarithromycin at twice their MICs produced a slow reduction in bacterial numbers, whereas azithromycin was bactericidal. Azithromycin at the concentrations achieved in the serum of humans was bacteriostatic, whereas erythromycin and clarithromycin were ineffective. In experimental respiratory tract infections in rats, clarithromycin (equivalent to 250 mg twice daily [b.i.d.]) and amoxicillin-clavulanate (equivalent to 500 plus 125 mg b.i.d., respectively) were highly effective against S. pneumoniae, but azithromycin (equivalent to 500 and 250 mg once daily) was significantly less effective (P < 0.01). Against H. influenzae, clarithromycin treatment (equivalent to 250 or 500 mg b.i.d.) was similar to no treatment and was significantly less effective than amoxicillin-clavulanate treatment (P < 0.01). Azithromycin demonstrated significant in vivo activity (P < 0.05) but was significantly less effective than amoxicillin-clavulanate (P < 0.05). Overall, amoxicillin-clavulanate was effective in vitro and in vivo. Clarithromycin and erythromycin were ineffective in vitro and in vivo against H. influenzae, and azithromycin (at concentrations achieved in humans) showed unreliable activity against both pathogens. These results may have clinical implications for the utility of macrolides in the empiric therapy of respiratory tract infections. PMID:9835514

Chemical interference with iron transport systems to suppress bacterial growth of Streptococcus pneumoniae.

PubMed

Yang, Xiao-Yan; Sun, Bin; Zhang, Liang; Li, Nan; Han, Junlong; Zhang, Jing; Sun, Xuesong; He, Qing-Yu

2014-01-01

Iron is an essential nutrient for the growth of most bacteria. To obtain iron, bacteria have developed specific iron-transport systems located on the membrane surface to uptake iron and iron complexes such as ferrichrome. Interference with the iron-acquisition systems should be therefore an efficient strategy to suppress bacterial growth and infection. Based on the chemical similarity of iron and ruthenium, we used a Ru(II) complex R-825 to compete with ferrichrome for the ferrichrome-transport pathway in Streptococcus pneumoniae. R-825 inhibited the bacterial growth of S. pneumoniae and stimulated the expression of PiuA, the iron-binding protein in the ferrichrome-uptake system on the cell surface. R-825 treatment decreased the cellular content of iron, accompanying with the increase of Ru(II) level in the bacterium. When the piuA gene (SPD_0915) was deleted in the bacterium, the mutant strain became resistant to R-825 treatment, with decreased content of Ru(II). Addition of ferrichrome can rescue the bacterial growth that was suppressed by R-825. Fluorescence spectral quenching showed that R-825 can bind with PiuA in a similar pattern to the ferrichrome-PiuA interaction in vitro. These observations demonstrated that Ru(II) complex R-825 can compete with ferrichrome for the ferrichrome-transport system to enter S. pneumoniae, reduce the cellular iron supply, and thus suppress the bacterial growth. This finding suggests a novel antimicrobial approach by interfering with iron-uptake pathways, which is different from the mechanisms used by current antibiotics.

Possible prevalence and transmission of acute respiratory tract infections caused by Streptococcus pneumoniae and Haemophilus influenzae among the internally displaced persons in tsunami disaster evacuation camps of Sri Lanka.

PubMed

Watanabe, Hiroshi; Batuwanthudawe, Ranjith; Thevanesam, Vasanthi; Kaji, Chiharu; Qin, Liang; Nishikiori, Nobuyuki; Saito, Wakana; Saito, Mariko; Watanabe, Kiwao; Oishi, Kazunori; Abeysinghe, Nihal; Kunii, Osamu

2007-01-01

The objective of this prospective study was to investigate the status of acute respiratory tract infections caused by Haemophilus influenzae and Streptococcus pneumoniae in tsunami disaster evacuation camps. Nasopharyngeal swabs (NP) of 324 internally displaced persons (IDP) in 3 different tsunami disaster evacuation camps of Sri Lanka were collected between March 18th and 20th, 2005, and analyzed for MIC, beta-lactamase production, serotypes, PCR and pulsed-field gel electrophoresis (PFGE). Many IDP had respiratory symptoms and the prevalence of cough and/or sputum was 84%, 70.5% and 64.7% in the three camps. Twenty-one H. influenzae from 20 IDP and 25 S. pneumoniae from 22 IDP were isolated from the NP. All H. influenzae isolates were nontypeable, and 5 were beta-lactamase producing. Seventeen pneumococci were susceptible, 5 showed intermediate resistance and 3 were fully resistant to penicillin G. Molecular analysis showed the 21 H. influenzae strains had 13 PFGE patterns and 25 pneumococci had 16 PFGE patterns. All 4 different PFGE patterns of H. influenzae strains were detected in a few IDP in camps 1 and 3, and 5 different PFGE patterns of serotype 3, 22A, 9A, 10A and 11A pneumococci were detected in a few IDP in camps 1 and 3. Our data indicate acute respiratory tract infections caused by various types of H. influenzae and S. pneumoniae appear to have been prevalent, some of which were potentially transmitted from person to person in tsunami disaster evacuation camps.

Medical Surveillance Monthly Report, Volume 20, Number 8

DTIC Science & Technology

2013-08-01

primary diagnostic position, 99 (55.6%) had secondary diagnoses indica- tive of infections (e.g., streptococcus infec- tion, cellulitis , UTI) (data not...respiratory infections (e.g., pneumonia), and skin infections (e.g., cellulitis ), all of which are risk factors for septicemia.7,12,13 It is not clear why

ENU Mutagenic Screen for Susceptibility and Resistance to Streptococcus Pneumoniae

DTIC Science & Technology

2005-11-07

collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for information Operations...NUMBER 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) U. S. Army Research Office P.O. Box 12211... Research Triangle Park, NC 27709-2211 10. SPONSORING / MONITORING AGENCY REPORT NUMBER

Streptococcus pneumoniae Coinfection Is Correlated with the Severity of H1N1 Pandemic Influenza

PubMed Central

Cisterna, Daniel; Savji, Nazir; Bussetti, Ana Valeria; Kapoor, Vishal; Hui, Jeffrey; Tokarz, Rafal; Briese, Thomas; Baumeister, Elsa; Lipkin, W. Ian

2009-01-01

Background Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease. Methods/Principal Findings We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0.0004). In subjects 6 to 55 years of age, the adjusted odds ratio (OR) of severe disease in the presence of S. pneumoniae was 125.5 (95% confidence interval [CI], 16.95, 928.72; p<0.0001). Conclusions/Significance The association of S. pneumoniae with morbidity and mortality is established in the current and previous influenza pandemics. However, this study is the first to demonstrate the prognostic significance of non-invasive antemortem diagnosis of S. pneumoniae infection and may provide insights into clinical management. PMID:20046873

Incidence of Hospitalized Pneumococcal Pneumonia among Adults in Guatemala, 2008-2012

PubMed Central

Contreras, Carmen Lucía; Verani, Jennifer R.; Lopez, María Renee; Paredes, Antonio; Bernart, Chris; Moscoso, Fabiola; Roldan, Aleida; Arvelo, Wences; Lindblade, Kim A.; McCracken, John P.

2015-01-01

Background Streptococcus pneumoniae is a leading cause of pneumonia worldwide. However, the burden of pneumococcal pneumonia among adults in low- and middle-income countries is not well described. Methods Data from 2008–2012 was analyzed from two surveillance sites in Guatemala to describe the incidence of pneumococcal pneumonia in adults. A case of hospitalized pneumococcal pneumonia was defined as a positive pneumococcal urinary antigen test or blood culture in persons aged ≥ 18 years hospitalized with an acute respiratory infection (ARI). Results Among 1595 adults admitted with ARI, 1363 (82%) had either urine testing (n = 1286) or blood culture (n = 338) performed. Of these, 188 (14%) had pneumococcal pneumonia, including 173 detected by urine only, 8 by blood culture only, and 7 by both methods. Incidence rates increased with age, with the lowest rate among 18–24 year-olds (2.75/100,000) and the highest among ≥65 year-olds (31.3/100,000). The adjusted incidence of hospitalized pneumococcal pneumonia was 18.6/100,000 overall, with in-hospital mortality of 5%. Conclusions An important burden of hospitalized pneumococcal pneumonia in adults was described, particularly for the elderly. However, even adjusted rates likely underestimate the true burden of pneumococcal pneumonia in the community. These data provide a baseline against which to measure the indirect effects of the 2013 introduction of the pneumococcal conjugate vaccine in children in Guatemala. PMID:26488871

Incidence of Hospitalized Pneumococcal Pneumonia among Adults in Guatemala, 2008-2012.

PubMed

Contreras, Carmen Lucía; Verani, Jennifer R; Lopez, María Renee; Paredes, Antonio; Bernart, Chris; Moscoso, Fabiola; Roldan, Aleida; Arvelo, Wences; Lindblade, Kim A; McCracken, John P

2015-01-01

Streptococcus pneumoniae is a leading cause of pneumonia worldwide. However, the burden of pneumococcal pneumonia among adults in low- and middle-income countries is not well described. Data from 2008-2012 was analyzed from two surveillance sites in Guatemala to describe the incidence of pneumococcal pneumonia in adults. A case of hospitalized pneumococcal pneumonia was defined as a positive pneumococcal urinary antigen test or blood culture in persons aged ≥ 18 years hospitalized with an acute respiratory infection (ARI). Among 1595 adults admitted with ARI, 1363 (82%) had either urine testing (n = 1286) or blood culture (n = 338) performed. Of these, 188 (14%) had pneumococcal pneumonia, including 173 detected by urine only, 8 by blood culture only, and 7 by both methods. Incidence rates increased with age, with the lowest rate among 18-24 year-olds (2.75/100,000) and the highest among ≥65 year-olds (31.3/100,000). The adjusted incidence of hospitalized pneumococcal pneumonia was 18.6/100,000 overall, with in-hospital mortality of 5%. An important burden of hospitalized pneumococcal pneumonia in adults was described, particularly for the elderly. However, even adjusted rates likely underestimate the true burden of pneumococcal pneumonia in the community. These data provide a baseline against which to measure the indirect effects of the 2013 introduction of the pneumococcal conjugate vaccine in children in Guatemala.

Cationic antimicrobial peptide resistance mechanisms of streptococcal pathogens.

PubMed

LaRock, Christopher N; Nizet, Victor

2015-11-01

Cationic antimicrobial peptides (CAMPs) are critical front line contributors to host defense against invasive bacterial infection. These immune factors have direct killing activity toward microbes, but many pathogens are able to resist their effects. Group A Streptococcus, group B Streptococcus and Streptococcus pneumoniae are among the most common pathogens of humans and display a variety of phenotypic adaptations to resist CAMPs. Common themes of CAMP resistance mechanisms among the pathogenic streptococci are repulsion, sequestration, export, and destruction. Each pathogen has a different array of CAMP-resistant mechanisms, with invasive disease potential reflecting the utilization of several mechanisms that may act in synergy. Here we discuss recent progress in identifying the sources of CAMP resistance in the medically important Streptococcus genus. Further study of these mechanisms can contribute to our understanding of streptococcal pathogenesis, and may provide new therapeutic targets for therapy and disease prevention. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides. Copyright © 2015 Elsevier B.V. All rights reserved.

Outcome of treatment of respiratory tract infections due to Streptococcus pneumoniae, including drug-resistant strains, with pharmacokinetically enhanced amoxycillin/clavulanate.

PubMed

File, Thomas M; Jacobs, Michael R; Poole, Michael D; Wynne, Brian

2002-10-01

The efficacy of a new pharmacokinetically enhanced formulation of amoxycillin/clavulanate (AMX/CA) 2000/125 mg, twice daily, designed to provide adequate levels of amoxycillin over the 12-h dosing interval to eradicate penicillin-resistant Streptococcus pneumoniae (PRSP) with amoxycillin (+/-clavulanic acid) MICs of /=4 mg/l. In the pooled comparator group, the success rate at follow-up was 86.5% (45/52). For PRSP (AMX/CA MICs of 0.5-8 mg/l), the overall success rate was 98.2% (55/56) at follow-up for AMX/CA 2000/125 mg and 50.0% (2/4) for comparators. AMX/CA 2000/125 mg shows efficacy comparable to that of the comparators evaluated against S. pneumoniae infections. Due to its favorable pharmacokinetic/pharmacodynamic profile and promising clinical success, the new AMX/CA 2000/125 mg formulation should be considered for the empirical treatment of respiratory tract infections in regions with a high prevalence of antimicrobial-resistant S. pneumoniae and in patients at high risk of antimicrobial-resistant S. pneumoniae infection as this formulation covers many PRSP that are non-susceptible to amoxycillin (+/-clavulanic acid) (MICs of >/=4 mg/l) as well as common beta-lactamase-producing respiratory pathogens.

Estimating the proportion of pneumonia attributable to pneumococcus in Kenyan adults: latent class analysis.

PubMed

Jokinen, Jukka; Scott, J Anthony G

2010-09-01

Community-acquired pneumonia is a common cause of hospitalization among African adults, and Streptococcus pneumoniae is assumed to be a frequent cause. Pneumococcal conjugate vaccine is currently being introduced into childhood immunization programs in Africa. The case for adult vaccination is dependent on the contribution of the pneumococcus to the hospital pneumonia burden. Pneumococcal diagnosis is complex because there is no gold standard, and culture methods are invalidated by antibiotic use. We used latent class analysis to estimate the proportion of pneumonia episodes caused by pneumococcus. Furthermore, we extended this methodology to evaluate the effect of antimicrobial treatment on test accuracies and the prevalence of the disease. The study combined data from 5 validation studies of pneumococcal diagnostic tests performed on 281 Kenyan adults with pneumonia. The proportion of pneumonia episodes attributable to pneumococcus was 0.46 (95% confidence interval = 0.36-0.57). Failure to account for the effect of antimicrobial exposure underestimates this proportion as 0.32. A history of antibiotic exposure was a poor predictor of antimicrobial activity in patients' urine. Blood culture sensitivity for pneumococcus was estimated at 0.24 among patients with antibiotic exposure, and 0.75 among those without. The large contribution of pneumococcus to adult pneumonia provides a strong case for the investigation of pneumococcal vaccines in African adults.

A decoy receptor 3 analogue reduces localised defects in phagocyte function in pneumococcal pneumonia.

PubMed

Marriott, Helen M; Daigneault, Marc; Thompson, Alfred A R; Walmsley, Sarah R; Gill, Sharonjit K; Witcher, Derrick R; Wroblewski, Victor J; Hellewell, Paul G; Whyte, Moira K B; Dockrell, David H

2012-11-01

Therapeutic strategies to modulate the host response to bacterial pneumonia are needed to improve outcomes during community-acquired pneumonia. This study used mice with impaired Fas signalling to examine susceptibility to pneumococcal pneumonia and decoy receptor 3 analogue (DcR3-a) to correct factors associated with increased susceptibility. Wild-type mice and those with varying degrees of impairment of Fas (lpr) or Fas ligand signalling (gld) were challenged with Streptococcus pneumoniae and microbiological and immunological outcomes measured in the presence or absence of DcR3-a. During established pneumonia, neutrophils became the predominant cell in the airway and gld mice were less able to clear bacteria from the lungs, demonstrating localised impairment of pulmonary neutrophil function in comparison to lpr or wild-type mice. T-cells from gld mice had enhanced activation and reduced apoptosis in comparison to wild-type and lpr mice during established pneumonia. Treatment with DcR3-a reduced T-cell activation and corrected the defect in pulmonary bacterial clearance in gld mice. The results suggest that imbalance in tumour necrosis factor superfamily signalling and excessive T-cell activation can impair bacterial clearance in the lung but that DcR3-a treatment can reduce T-cell activation, restore optimal pulmonary neutrophil function and enhance bacterial clearance during S pneumoniae infection.

Pneumococcal pneumonia: clinical features, diagnosis and management in HIV-infected and HIV noninfected patients.

PubMed

Madeddu, Giordano; Fois, Alessandro Giuseppe; Pirina, Pietro; Mura, Maria Stella

2009-05-01

In this review, we focus on the clinical features, diagnosis and management of pneumococcal pneumonia in HIV-infected and noninfected patients, with particular attention to the most recent advances in this area. Classical clinical features are found in young adults, whereas atypical forms occur in immunocompromised patients including HIV-infected individuals. Bacteremic pneumococcal pneumonia is more frequently observed in HIV-infected and also in low-risk patients, according to the Pneumonia Severity Index (PSI). Pneumococcal pneumonia diagnostic process includes physical examination, radiologic findings and microbiologic diagnosis. However, etiologic diagnosis using traditional culture methods is difficult to obtain. In this setting, urinary antigen test, which recognizes Streptococcus pneumoniae cell wall C-polysaccharide, increases the probability of etiologic diagnosis. A correct management approach is crucial in reducing pneumococcal pneumonia mortality. The use of the PSI helps clinicians in deciding between inpatient and outpatient management in immunocompetent individuals, according to Infectious Diseases Society of America (IDSA)-American Thoracic Society (ATS) guidelines. Recent findings support PSI utility also in HIV-infected patients. Recently, efficacy of pneumococcal vaccine in reducing pneumococcal disease incidence has been evidenced in both HIV-infected and noninfected individuals. Rapid diagnosis and correct management together with implementation of preventive measures are crucial in order to reduce pneumococcal pneumonia related incidence and mortality in HIV-infected and noninfected patients.

Upregulation of the PatAB Transporter Confers Fluoroquinolone Resistance to Streptococcus pseudopneumoniae

PubMed Central

Alvarado, María; Martín-Galiano, Antonio J.; Ferrándiz, María J.; Zaballos, Ángel; de la Campa, Adela G.

2017-01-01

We characterized the mechanism of fluoroquinolone-resistance in two isolates of Streptococcus pseudopneumoniae having fluoroquinolone-efflux as unique mechanism of resistance. Whole genome sequencing and genetic transformation experiments were performed together with phenotypic determinations of the efflux mechanism. The PatAB pump was identified as responsible for efflux of ciprofloxacin (MIC of 4 μg/ml), ethidium bromide (MICs of 8–16 μg/ml) and acriflavine (MICs of 4–8 μg/ml) in both isolates. These MICs were at least 8-fold lower in the presence of the efflux inhibitor reserpine. Complete genome sequencing indicated that the sequence located between the promoter of the patAB operon and the initiation codon of patA, which putatively forms an RNA stem-loop structure, may be responsible for the efflux phenotype. RT-qPCR determinations performed on RNAs of cultures treated or not treated with subinhibitory ciprofloxacin concentrations were performed. While no significant changes were observed in wild-type Streptococcus pneumoniae R6 strain, increases in transcription were detected in the ciprofloxacin-efflux transformants obtained with DNA from efflux-positive isolates, in the ranges of 1.4 to 3.4-fold (patA) and 2.1 to 2.9-fold (patB). Ciprofloxacin-induction was related with a lower predicted free energy for the stem-loop structure in the RNA of S. pseudopneumoniae isolates (−13.81 and −8.58) than for R6 (−15.32 kcal/mol), which may ease transcription. The presence of these regulatory variations in commensal S. pseudopneumoniae isolates, and the possibility of its transfer to Streptococcus pneumoniae by genetic transformation, could increase fluoroquinolone resistance in this important pathogen. PMID:29123510

The clinical presentation of Fusobacterium-positive and streptococcal-positive pharyngitis in a university health clinic: a cross-sectional study.

PubMed

Centor, Robert M; Atkinson, T Prescott; Ratliff, Amy E; Xiao, Li; Crabb, Donna M; Estrada, Carlos A; Faircloth, Michael B; Oestreich, Lisa; Hatchett, Jeremy; Khalife, Walid; Waites, Ken B

2015-02-17

Pharyngitis guidelines focus solely on group A β-hemolytic streptococcal infection. European data suggest that in patients aged 15 to 30 years, Fusobacterium necrophorum causes at least 10% of cases of pharyngitis; however, few U.S. data exist. To estimate the prevalence of F. necrophorum; Mycoplasma pneumoniae; and group A and C/G β-hemolytic streptococcal pharyngitis and to determine whether F. necrophorum pharyngitis clinically resembles group A β-hemolytic streptococcal pharyngitis. Cross-sectional. University student health clinic. 312 students aged 15 to 30 years presenting to a student health clinic with an acute sore throat and 180 asymptomatic students. Polymerase chain reaction testing from throat swabs to detect 4 species of bacteria and signs and symptoms used to calculate the Centor score. Fusobacterium necrophorum was detected in 20.5% of patients and 9.4% of asymptomatic students. Group A β-hemolytic streptococcus was detected in 10.3% of patients and 1.1% of asymptomatic students. Group C/G β-hemolytic streptococcus was detected in 9.0% of patients and 3.9% of asymptomatic students. Mycoplasma pneumoniae was detected in 1.9% of patients and 0 asymptomatic students. Infection rates with F. necrophorum, group A streptococcus, and group C/G streptococcus increased with higher Centor scores (P < 0.001). The study focused on a limited age group and took place at a single institution. Asymptomatic students-rather than seasonal control participants-and a convenience sample were used. Fusobacterium necrophorum-positive pharyngitis occurs more frequently than group A β-hemolytic streptococcal-positive pharyngitis in a student population, and F. necrophorum-positive pharyngitis clinically resembles streptococcal pharyngitis. University of Alabama at Birmingham and the Justin E. Rodgers Foundation.

DNA methylase activity as a marker for the presence of a family of phage-like elements conferring efflux-mediated macrolide resistance in streptococci.

PubMed

Figueiredo, T A; Aguiar, S I; Melo-Cristino, J; Ramirez, M

2006-11-01

Recently, two related chimeric genetic elements (Tn1207.3 and Phi10394.4) were shown to carry the macrolide efflux gene mef in Streptococcus pyogenes (group A streptococci [GAS]). The dissemination of elements belonging to the Tn1207.3/Phi10394.4 family in recent isolates of GAS, Streptococcus dysgalactiae subsp. equisimilis, Streptococcus pneumoniae, and Streptococcus agalactiae recovered in Portugal was surveyed. In total, 149 GAS, 18 S. pneumoniae, 4 S. dysgalactiae subsp. equisimilis, and 5 S. agalactiae isolates from infections, presenting the M phenotype of macrolide resistance and containing the mef gene, were screened for the presence of Tn1207.3/Phi10394.4 by PCR targeting open reading frames (ORFs) specific for these related elements. All the GAS isolates tested and one of the S. dysgalactiae subsp. equisimilis isolates carried Tn1207.3. However, neither of these elements was found in the isolates of the other streptococcal species. It was also noted that the DNAs of the isolates carrying Tn1207.3 were resistant to cleavage by the endonuclease SmaI. Cloning and expression of ORF12 of Tn1207.3 in Escherichia coli showed that it encoded a methyltransferase that rendered DNA refractory to cleavage by SmaI (M.Spy10394I). Using this characteristic as a marker for the presence of the Tn1207.3/Phi10394.4 family, we reviewed the literature and concluded that these genetic elements are widely distributed among tetracycline-susceptible GAS isolates presenting the M phenotype from diverse geographic origins and may have played an important role in the dissemination of macrolide resistance in this species.

Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract.

PubMed

Li, Hong; Yang, Tian; Li, Fei-Yan; Yao, Yan; Sun, Zhong-Min

2014-01-01

The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2', 7'-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results.

Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract

PubMed Central

Li, Hong; Yang, Tian; Li, Fei-Yan; Yao, Yan; Sun, Zhong-Min

2014-01-01

The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2’, 7’-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results. PMID:25550774

SEPAR-ALAT Consensus Document on Antipneumoccal Vaccination in Smokers.

PubMed

Jiménez Ruiz, Carlos A; Buljubasich, Daniel; Sansores, Raúl; Riesco Miranda, Juan Antonio; Guerreros Benavides, Alfredo; Luhning, Susana; Chatkin, José Miguel; Zabert, Gustavo; de Granda Orive, José Ignacio; Solano Reina, Segismundo; Casas Herrera, Alejandro; de Lucas Ramos, Pilar

2015-07-01

Streptococcus pneumoniae is responsible for several clinical syndromes, such as community-acquired pneumonia, sinusitis, otitis media, and others. The most severe clinical entity caused by this bacteria is undoubtedly invasive pneumococcal disease. Certain factors are known to increase the risk of presenting invasive pneumococcal disease, the most important being smoking habit and underlying concomitant diseases. This article comprises a consensus document on antipneumococcal vaccination in smokers, drawn up by a Smoking Expert Group from the Spanish Society of Pulmonology and Thoracic Surgery and the Latin American Chest Association. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

RlmCD-mediated U747 methylation promotes efficient G748 methylation by methyltransferase RlmAII in 23S rRNA in Streptococcus pneumoniae; interplay between two rRNA methylations responsible for telithromycin susceptibility

PubMed Central

Shoji, Tatsuma; Takaya, Akiko; Sato, Yoshiharu; Kimura, Satoshi; Suzuki, Tsutomu; Yamamoto, Tomoko

2015-01-01

Adenine at position 752 in a loop of helix 35 from positions 745 to 752 in domain II of 23S rRNA is involved in binding to the ribosome of telithromycin (TEL), a member of ketolides. Methylation of guanine at position 748 by the intrinsic methyltransferase RlmAII enhances binding of telithromycin (TEL) to A752 in Streptococcus pneumoniae. We have found that another intrinsic methylation of the adjacent uridine at position 747 enhances G748 methylation by RlmAII, rendering TEL susceptibility. U747 and another nucleotide, U1939, were methylated by the dual-specific methyltransferase RlmCD encoded by SP_1029 in S. pneumoniae. Inactivation of RlmCD reduced N1-methylated level of G748 by RlmAII in vivo, leading to TEL resistance when the nucleotide A2058, located in domain V of 23S rRNA, was dimethylated by the dimethyltransferase Erm(B). In vitro methylation of rRNA showed that RlmAII activity was significantly enhanced by RlmCD-mediated pre-methylation of 23S rRNA. These results suggest that RlmCD-mediated U747 methylation promotes efficient G748 methylation by RlmAII, thereby facilitating TEL binding to the ribosome. PMID:26365244

Comparative antibacterial effects of moxifloxacin and levofloxacin on Streptococcus pneumoniae strains with defined mechanisms of resistance: impact of bacterial inoculum.

PubMed

Bowker, K E; Garvey, M I; Noel, A R; Tomaselli, S G; Macgowan, A P

2013-05-01

We aim to further define the impact of the mechanism of fluoroquinolone resistance and inoculum load on the pharmacodynamic effects of levofloxacin and moxifloxacin on Streptococcus pneumoniae. The antibacterial effects of and emergence of resistance (EoR) to moxifloxacin (400 mg once daily) or levofloxacin (750 mg once daily or 500 mg twice daily) were compared using five S. pneumoniae strains containing no known resistance mechanisms, efflux resistance mechanisms, a parC mutation or parC and gyrA mutations, at high (10(8) cfu/mL) and low (10(6) cfu/mL) inocula. An in vitro pharmacokinetic model was used and simulations were performed over 96 h. After drug exposure, isolates were tested for the presence of efflux pumps and mutations in the quinolone resistance-determining regions. A high inoculum diminished the antibacterial effect of moxifloxacin and levofloxacin. Levofloxacin at both dosages produced EoR with all strains. Levofloxacin regimens with AUC/MIC ratios <100 produced EoR. Moxifloxacin produced EoR with the parC strain only. Levofloxacin dosing regimens with low AUC/MIC ratios select for efflux pump overexpression, leading to fluoroquinolone resistance. Levofloxacin dosing may select for gyrA mutations, inducing moxifloxacin resistance. These data confirm that a fluoroquinolone AUC/MIC ratio of >100 is required for prevention of EoR.

Kinetics of Coinfection with Influenza A Virus and Streptococcus pneumoniae

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

Smith, Amber M.; Adler, Frederick R.; Ribeiro, Ruy M.

Secondary bacterial infections are a leading cause of illness and death during epidemic and pandemic influenza. Experimental studies suggest a lethal synergism between influenza and certain bacteria, particularly Streptococcus pneumoniae, but the precise processes involved are unclear. In this paper, to address the mechanisms and determine the influences of pathogen dose and strain on disease, we infected groups of mice with either the H1N1 subtype influenza A virus A/Puerto Rico/8/34 (PR8) or a version expressing the 1918 PB1-F2 protein (PR8-PB1-F2(1918)), followed seven days later with one of two S. pneumoniae strains, type 2 D39 or type 3 A66.1. We determinedmore » that, following bacterial infection, viral titers initially rebound and then decline slowly. Bacterial titers rapidly rise to high levels and remain elevated. We used a kinetic model to explore the coupled interactions and study the dominant controlling mechanisms. We hypothesize that viral titers rebound in the presence of bacteria due to enhanced viral release from infected cells, and that bacterial titers increase due to alveolar macrophage impairment. Dynamics are affected by initial bacterial dose but not by the expression of the influenza 1918 PB1-F2 protein. Finally, our model provides a framework to investigate pathogen interaction during coinfections and to uncover dynamical differences based on inoculum size and strain.« less

Evolution of antimicrobial resistance and serotype distribution of Streptococcus pneumoniae isolated from children with invasive and noninvasive pneumococcal diseases in Algeria from 2005 to 2012

PubMed Central

Ramdani-Bouguessa, N.; Ziane, H.; Bekhoucha, S.; Guechi, Z.; Azzam, A.; Touati, D.; Naim, M.; Azrou, S.; Hamidi, M.; Mertani, A.; Laraba, A.; Annane, T.; Kermani, S.; Tazir, M.

2015-01-01

Pneumococcal infections are a major cause of morbidity and mortality in developing countries. The introduction of pneumococcal conjugate vaccines (PCVs) has dramatically reduced the incidence of pneumococcal diseases. PCVs are not currently being used in Algeria. We conducted a prospective study from 2005 to 2012 in Algeria to determine antimicrobial drug resistance and serotype distribution of Streptococcus pneumoniae from children with pneumococcal disease. Among 270 isolated strains from children, 97 (36%) were invasive disease; of these, 48% were not susceptible to penicillin and 53% not susceptible to erythromycin. A high rate of antimicrobial nonsusceptibility was observed in strains isolated from children with meningitis. The serotype distribution from pneumococci isolated from children with invasive infections was (by order of prevalence): 14, 1, 19F, 19A, 6B, 5, 3, 6A and 23F. Multidrug resistance was observed in serotypes 14, 19F, 19A and 6B. The vaccine coverage of serotypes isolated from children aged <5 years was 55.3% for PCV7, 71.1% for PCV10 and 86.8% for PCV13. Our results highlight the burden of pneumococcal disease in Algeria and the increasing S. pneumoniae antibiotic resistance. The current pneumococcal vaccines cover a high percentage of the circulating strains. Therefore, vaccination would reduce the incidence of pneumococcal disease in Algeria. PMID:26106481

Deletion analysis of Streptococcus pneumoniae late competence genes distinguishes virulence determinants that are dependent or independent of competence induction.

PubMed

Zhu, Luchang; Lin, Jingjun; Kuang, Zhizhou; Vidal, Jorge E; Lau, Gee W

2015-07-01

The competence regulon of Streptococcus pneumoniae (pneumococcus) is crucial for genetic transformation. During competence development, the alternative sigma factor ComX is activated, which in turn, initiates transcription of 80 'late' competence genes. Interestingly, only 16 late genes are essential for genetic transformation. We hypothesized that these late genes that are dispensable for competence are beneficial to pneumococcal fitness during infection. These late genes were systematically deleted, and the resulting mutants were examined for their fitness during mouse models of bacteremia and acute pneumonia. Among these, 14 late genes were important for fitness in mice. Significantly, deletion of some late genes attenuated pneumococcal fitness to the same level in both wild-type and ComX-null genetic backgrounds, suggesting that the constitutive baseline expression of these genes was important for bacterial fitness. In contrast, some mutants were attenuated only in the wild-type genetic background but not in the ComX-null background, suggesting that specific expression of these genes during competence state contributed to pneumococcal fitness. Increased virulence during competence state was partially caused by the induction of allolytic enzymes that enhanced pneumolysin release. These results distinguish the role of basal expression versus competence induction in virulence functions encoded by ComX-regulated late competence genes. © 2015 John Wiley & Sons Ltd.

Choline Binding Proteins from Streptococcus pneumoniae: A Dual Role as Enzybiotics and Targets for the Design of New Antimicrobials

PubMed Central

Maestro, Beatriz; Sanz, Jesús M.

2016-01-01

Streptococcus pneumoniae (pneumococcus) is an important pathogen responsible for acute invasive and non-invasive infections such as meningitis, sepsis and otitis media, being the major cause of community-acquired pneumonia. The fight against pneumococcus is currently hampered both by insufficient vaccine coverage and by rising antimicrobial resistances to traditional antibiotics, making necessary the research on novel targets. Choline binding proteins (CBPs) are a family of polypeptides found in pneumococcus and related species, as well as in some of their associated bacteriophages. They are characterized by a structural organization in two modules: a functional module (FM), and a choline-binding module (CBM) that anchors the protein to the choline residues present in the cell wall through non-covalent interactions. Pneumococcal CBPs include cell wall hydrolases, adhesins and other virulence factors, all playing relevant physiological roles for bacterial viability and virulence. Moreover, many pneumococcal phages also make use of hydrolytic CBPs to fulfill their infectivity cycle. Consequently, CBPs may play a dual role for the development of novel antipneumococcal drugs, both as targets for inhibitors of their binding to the cell wall and as active cell lytic agents (enzybiotics). In this article, we review the current state of knowledge about host- and phage-encoded pneumococcal CBPs, with a special focus on structural issues, together with their perspectives for effective anti-infectious treatments. PMID:27314398

Kinetics of Coinfection with Influenza A Virus and Streptococcus pneumoniae

DOE PAGES

Smith, Amber M.; Adler, Frederick R.; Ribeiro, Ruy M.; ...

2013-03-21

Secondary bacterial infections are a leading cause of illness and death during epidemic and pandemic influenza. Experimental studies suggest a lethal synergism between influenza and certain bacteria, particularly Streptococcus pneumoniae, but the precise processes involved are unclear. In this paper, to address the mechanisms and determine the influences of pathogen dose and strain on disease, we infected groups of mice with either the H1N1 subtype influenza A virus A/Puerto Rico/8/34 (PR8) or a version expressing the 1918 PB1-F2 protein (PR8-PB1-F2(1918)), followed seven days later with one of two S. pneumoniae strains, type 2 D39 or type 3 A66.1. We determinedmore » that, following bacterial infection, viral titers initially rebound and then decline slowly. Bacterial titers rapidly rise to high levels and remain elevated. We used a kinetic model to explore the coupled interactions and study the dominant controlling mechanisms. We hypothesize that viral titers rebound in the presence of bacteria due to enhanced viral release from infected cells, and that bacterial titers increase due to alveolar macrophage impairment. Dynamics are affected by initial bacterial dose but not by the expression of the influenza 1918 PB1-F2 protein. Finally, our model provides a framework to investigate pathogen interaction during coinfections and to uncover dynamical differences based on inoculum size and strain.« less

Rise of multidrug-resistant non-vaccine serotype 15A Streptococcus pneumoniae in the United Kingdom, 2001 to 2014

PubMed Central

Sheppard, Carmen; Fry, Norman K.; Mushtaq, Shazad; Woodford, Neil; Reynolds, Rosy; Janes, Regina; Pike, Rachel; Hill, Robert; Kimuli, Maimuna; Staves, Peter; Doumith, Michel; Harrison, Timothy; Livermore, David M

2016-01-01

Conjugate vaccines have reduced pneumococcal disease in vaccinated children and unvaccinated adults, but non-vaccine serotypes are of concern, particularly if antibiotic resistant. We reviewed Streptococcus pneumoniae collected via: (i) the British Society for Antimicrobial Chemotherapy (BSAC) surveillances from 2001–2014; (ii) Public Health England’s (PHE) invasive isolate surveillance from 2005–2014 and (iii) referral to PHE for resistance investigation from 2005–2014. Serotype 15A increased in all series, with many representatives showing triple resistance to macrolides, tetracyclines and penicillin. 15A was consistently among the 10 most prevalent serotypes from 2011 in PHE and BSAC invasive isolate/bacteraemia surveillance but never previously; 26–33% of these invasive 15A isolates had triple resistance. BSAC respiratory isolates were only serotyped in 2013/14 and 2014/15 (October to September); 15A was most prevalent serotype in both periods, comprising 9–11% of isolates, 38–48% of them with triple resistance. Serotype 15A represented 0–4% of S. pneumoniae referred to PHE for reference investigation annually until 2008 but rose to 29% (2013) and 32% (2014). Almost all multidrug-resistant 15A isolates were sequence type (ST) 63 variants, whereas susceptible 15A isolates were clonally diverse. The rise of serotype 15A suggests that pneumococcal conjugate vaccines will need ongoing adaptation. PMID:28006650

Characterization of Streptococcus pneumoniae thymidylate kinase: steady-state kinetics of the forward reaction and isothermal titration calorimetry.

PubMed Central

Petit, Chantal M; Koretke, Kristin K

2002-01-01

Thymidylate kinase (TMK) catalyses the phosphorylation of dTMP to form dTDP in both the de novo and salvage pathways of dTTP synthesis. The tmk gene from the bacterial pathogen Streptococcus pneumoniae was identified. The gene, encoding a 212-amino-acid polypeptide (23352 Da), was cloned and overexpressed in Escherichia coli with an N-terminal hexahistidine tag. The enzyme was purified to homogeneity, and characterized in the forward reaction. The pH profile of TMK indicates that its activity is optimal at pH 8.5. The substrate specificity of the enzyme was examined; it was found that not only ATP, but also dATP and to a lesser extent CTP, could act as phosphate donors, and dTMP and dUMP could serve as phosphate acceptors. Furthermore, AZT-MP (3'-azido-3'-deoxythymidine 5'-monophosphate) was shown not to be a substrate for S. pneumoniae TMK. Steady-state kinetics and inhibition studies with adenosine 5'-[beta-thio]diphosphate and dTDP in addition to isothermal titration calorimetry were performed. The data showed that binding follows an ordered pathway, in which ATP binds first with a K(m) of 235 +/- 46 microM and a K(d) of 116 +/- 3 microM, and dTMP binds secondly with a K(m) of 66 +/- 12 microM and a K(d) of 53 +/- 2 microM. PMID:11964185