... with facebook share with twitter share with linkedin Tuberculosis (TB) Tuberculosis (TB) is a contagious and often ... are drug resistant. Why Is the Study of Tuberculosis (TB) a Priority for NIAID? Tuberculosis is one ...
... Training Home Conditions Tuberculosis (TB) Treating Tuberculosis Treating Tuberculosis Make an Appointment Refer a Patient Ask a ... bones is treated longer. NEXT: Preventive Treatment Diagnosing Tuberculosis History of TB Clinical Trials For more than ...
... AIDS-Related Opportunistic Infections and Coinfections HIV and Tuberculosis (TB) (Last updated 9/1/2016; last reviewed ... depends on a person’s individual circumstances. What is tuberculosis? Tuberculosis (TB) is a contagious disease that can ...
Tuberculosis (TB) Facts Testing for TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination
Tuberculosis (TB) Facts Exposure to TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination
Pieroni, Marco; Tipparaju, Suresh K; Lun, Shichun; Song, Yang; Sturm, A Willem; Bishai, William R; Kozikowski, Alan P
The struggle against tuberculosis (TB) is still far from over. TB, caused by Mycobacterium tuberculosis, is one of the deadliest infections worldwide. Co-infection with human immunodeficiency virus (HIV) and the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains have further increased the burden for this disease. Herein, we report the discovery of 2-(4-chlorobenzyl)-3-methyl-1-oxo-1H,5H-pyrido[1,2-a]benzimidazole-4-carbonitrile as an effective antitubercular agent and the structural modifications of this molecule that have led to analogues with improved potency and lower toxicity. A number of these derivatives were also active at sub-micromolar concentrations against resistant TB strains and devoid of apparent toxicity to Vero cells, thereby underscoring their value as novel scaffolds for the development of new anti-TB drugs.
Tuberculosis (TB) Facts TB and HIV/AIDS What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination
Rakotosamimanana, Niaina; Richard, Vincent; Raharimanga, Vaomalala; Gicquel, Brigitte; Doherty, T Mark; Zumla, Alimuddin; Rasolofo Razanamparany, Voahangy
Identifying those Mycobacterium tuberculosis latent-infected individuals most at risk of developing active tuberculosis (TB) using routine clinical and laboratory tests remains a huge challenge in TB control efforts. We conducted a prospective longitudinal study of clinical and laboratory markers associated with the risk of developing active TB in contacts with latent M. tuberculosis infection.HIV-negative household contacts (n=296) of pulmonary TB patients underwent monitoring of clinical features, full blood cell counts, tuberculin skin text (TST) and chest radiography performed regularly during 18 months of follow-up. Paired statistical tests, a Kaplan-Meier analysis and Cox proportional hazard modelling were performed on variables between contacts progressing or not progressing to active TB.The appearance of TB disease symptoms in contacts was significantly associated with an elevated peripheral percentage of blood monocytes (adjusted hazard ratio (aHR) 6.25, 95% CI 1.63-23.95; p<0.01), a ≥14 mm TST response (aHR 5.72, 95% CI 1.22-26.80; p=0.03) and an increased monocyte:lymphocyte ratio (aHR 4.97, 95% CI 1.3-18.99; p=0.03). Among contacts having TST ≥14 mm, a strong association with risk of progression to TB was found with an elevated blood monocyte percentage (aHR 8.46, 95% CI 1.74-41.22; p<0.01).Elevated percentage of peripheral blood monocytes plus an elevated TST response are potential biomarkers for identifying contacts of TB patients at highest risk of developing active TB.
Tuberculosis (TB) Facts You Can Prevent TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination TB Facts: You Can Prevent TB What ...
Tuberculosis (TB) Facts TB Can Be Treated What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination Page 1 of 2 TB Facts: TB ...
Simsek, Hulya; Alpar, Sibel; Ucar, Nazire; Aksu, Funda; Ceyhan, Ismail; Gözalan, Aysegul; Cesur, Salih; Ertek, Mustafa
The T-SPOT.TB test does not cross-react with Bacille Calmette-Guérin or most non-tuberculosis mycobacterium species, and is based on IFN-gamma responses to Mycobacterium tuberculosis-specific antigens. The objective of this study was to compare tuberculin skin test (TST) with T-SPOT.TB results used in the diagnosis of active tuberculosis (TB) as well as latent tuberculosis infection (LTBI). A total of 136 subjects participated in three different groups (47 patients with active pulmonary TB, 47 healthy persons without M. tuberculosis exposure, and 42 hospital members with a history of close contact with active TB patients). The T-SPOT.TB sensitivity (83.0%) and the negative predictive value (NPV) (82.6%) in the diagnosis of active TB were significantly higher than those of TST. The sensitivity and NPV of the TST were 38.3 and 60.8%, respectively. The T-SPOT.TB specificity (80.9%) and positive predictive value (81.3%) were lower than those of TST (95.7 and 90.0%, respectively). The performance of T-SPOT.TB and TST for diagnosing LTBI was the same (54.8%). T-SPOT.TB was superior in terms of sensitivity (83.0%); TST detected only 18, whereas T-SPOT.TB test detected 39 out of 47 patients with active TB. T-SPOT.TB is thought to have better performance than TST due to false-negative results in diagnosing active TB. However, it is considered that large prospective longitudinal studies are needed for diagnosing LTBI.
Cheon, Seon Ah; Cho, Hyun Hee; Kim, Jeonghyo; Lee, Jaebeom; Kim, Hwa-Jung; Park, Tae Jung
Tuberculosis (TB) is an infectious bacterial disease caused by Mycobacterium tuberculosis. Despite global TB eradication efforts, it is still a global public health concern, especially in low- and middle-income countries. Most of the active TB infections are curable with early diagnosis and appropriate treatment, but drug-resistant TB is difficult and expensive to treat in immunocompetent as well as immunocompromised individuals. Thus, rapid, economic, and accurate point-of care tools for TB diagnosis are required urgently. This review describes the history of M. tuberculosis detection methods up to date and the recent advances using nanotechnology for point-of-care testing of TB diagnosis.
Chiappini, Elena; Bonsignori, Francesca; Mangone, Giusi; Galli, Luisa; Mazzantini, Rachele; Sollai, Sara; Azzari, Chiara; de Martino, Maurizio
We performed a prospective study to investigate T-SPOT.TB and QuantiFERON-TB Gold In-Tube (QFT-G-IT) dynamics during antitubercular treatment in active tuberculosis (TB) or latent TB. Eighteen children with latent TB and 26 with TB were enrolled. At 6 months of follow-up reversion rate was 5.88% (95% CI:0-13.79) for QFT-G-IT; 9.09% (95% CI:0.59-17.58) for T-SPOT.TB (P=0.921) in TB cases. Significant decline in quantitative response was observed exclusively in TB cases. Our results suggest that serial IGRA have limited use in children receiving antitubercular treatment.
... What's this? Submit Button Past Emails CDC Features Tuberculosis (TB) Disease: Symptoms & Risk Factors Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir Tuberculosis (TB) is a disease caused by bacteria that ...
... HUMAN SERVICES Centers for Disease Control and Prevention Community Preparation for Tuberculosis (TB..., , as amended. Purpose: The purpose of the program is for CDC to test new Tuberculosis (TB) vaccines... limited to, World Health Organization (WHO), International Union Against Tuberculosis and Lung...
Paluch-Oleś, Jolanta; Magryś, Agnieszka; Kot, Ewa; Kozioł-Montewka, Maria
Diagnosis of extrapulmonary tuberculosis (TB) is often missed or delayed because of nonspecific clinical and laboratory findings. Novel detection methods, such as polymerase chain reaction and QuantiFERON-TB Gold In Tube, can aid in the diagnosis of active extrapulmonary TB. Here, we demonstrate a case of epididymo-orchitis as the sole presentation of TB in a 32-year-old man.
Chang, Ping-Chin; Wang, Pin-Hui; Chen, Kow-Tong
The value of QuantiFERON in the diagnosis of tuberculosis disease and in the monitoring of the response to anti-tuberculosis treatment is unclear. The aims of this study were to evaluate the accuracy of the QuantiFERON-TB Gold In-Tube (QFT-GIT) test in the diagnosis of tuberculosis and in the monitoring of the response to anti-tuberculosis treatment in patients with active pulmonary tuberculosis (PTB). Between January 2013 and December 2015, 133 cases with active PTB and 133 controls with no mycobacterial infection, matched by age (within 3 years) and by the week that they visited Tainan Chest Hospital, were enrolled in the study. Serial testing by QFT-GIT at baseline and after 2 and 6 months of treatment was performed. At these time points, a comparison of the performance of QFT-GIT with that of sputum culture status among study subjects was conducted. Compared to baseline, 116 (87.2%) cases showed a decreased response, whereas 17 (12.8%) showed persistent or stronger interferon-gamma (IFN-γ) responses at 2 months. PTB patients IFN-γ responses declined significantly from baseline to 2 months (median, 6.32 vs. 4.12; p < 0.005). The sensitivity values of the QFT-GIT test for the detection of pulmonary tuberculosis at cut-off points of 0.35 IU/mL, 0.20 IU/mL, and 0.10 IU/mL were 74.4%, 78.2%, and 80.5%, respectively. The specificity values at cut-off points of 0.35 IU/mL, 0.20 IU/mL, and 0.10 IU/mL were 66.2%, 63.9%, and 57.1%, respectively. Our results support the QFT-GIT assay as a potential tool for diagnosing tuberculosis and for monitoring the efficacy of anti-tuberculosis treatment. PMID:28264462
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Shen, Lei; Gao, Yan; Liu, Yuanyuan; Zhang, Bingyan; Liu, Qianqian; Wu, Jing; Fan, Lin; Ou, Qinfang; Zhang, Wenhong; Shao, Lingyun
The role of the PD-1/PD-L pathway in a murine model of tuberculosis remains controversial regarding viral infections and clinical tuberculosis. We conducted a case-control study to investigate the modulating role and mechanism of the PD-1/PD-L pathway in patients with active tuberculosis. Fifty-nine participants, including 43 active tuberculosis (ATB) patients and 16 healthy controls (HC), were enrolled. Cell surface staining and flow cytometry were used to detect the expressions of PD-1 and its ligands on T cells and monocytes. Intracellular cytokine staining was used to determine the PPD-specific IFN-γ-secreting T-cell proportion. CD4+ T-cell proliferation and macrophage functions were investigated in the presence or absence of PD-1/PD-L pathway blockade. Proportions of both PD-1+CD4+ and PD-L1+CD4+ T cells in ATB patients were more significantly increased than in the HC group (P = 0.0112 and P = 0.0141, respectively). The expressions of PD-1, PD-L1, and PD-L2 on CD14+ monocytes in ATB patients were much higher than those in the HC group (P = 0.0016, P = 0.0001, and P = 0.0088, respectively). Blockade of PD-1 could significantly enhance CD4+ T-cell proliferation (P = 0.0433). Phagocytosis and intracellular killing activity of macrophages increased significantly with PD-1/PD-L pathway blockade. In conclusion, the PD-1/PD-L pathway inhibits not only M.tb-specific CD4+ T-cell-mediated immunity but also innate immunity. PMID:27924827
Ben-Selma, Walid; Ben-Kahla, Imen; Marzouk, Manel; Ferjeni, Asma; Ghezal, Samira; Ben-Said, Moncef; Boukadida, Jalel
The usefulness of a new rapid diagnostic test (Patho-TB) using antibodies specific to mycobacterial antigens was evaluated for the rapid discrimination between pulmonary tuberculosis (TB) and non-TB pulmonary diseases on sputa. One hundred sputa collected from 79 active TB patients and from 21 patients with non-TB pulmonary diseases (asthma and chronic obstructive pulmonary disease) were enrolled into the study and tested for the presence of Mycobacterium tuberculosis by Ziehl-Neelsen smear, Patho-TB kit, and Löwenstein-Jensen culture. The sensitivity, specificity, positive predictive value, and negative predictive value of the Patho-TB test were 95%, 100%, 100%, and 84%, respectively. Patho-TB test is simple, quick, and easy to perform. Its sensitivity, specificity, and positive predictive value are satisfactory. Therefore, it could be used as a screening test in poorly equipped laboratories of TB endemic areas.
... person with infectious TB coughs or sneezes, droplet nuclei containing M. tuberculosis are expelled into the air. If another person inhales air containing these droplet nuclei, he or she may become infected. However, not ...
Haumba, S; Dlamini, T; Calnan, M; Ghazaryan, V; Smith-Arthur, A E; Preko, P; Ehrenkranz, P
This retrospective observational review documents the efforts of the Swaziland National Tuberculosis (TB) Control Programme between 2004 and 2014. The objective is to describe the disparity between actual declines in case notification and increases in estimated incidence. The review of policies and practices shows the most influential factors associated with the decrease in TB case notification to be an increase in access to antiretroviral therapy for co-infected TB patients, the general success of TB and human immunodeficiency virus service integration in the country and improvements in implementation of all components of directly observed treatment, active case finding, and rapid diagnosis using new technologies.
The condition of tuberculosis (TB) at the time at which an individual is diagnosed with TB influences the patient's prognosis. This paper focuses on the condition of TB at the time of the diagnosis based on bacteriological status and X-ray findings. The proportion of bacteriologically confirmed cases among newly notified pulmonary TB patients increased greatly from 25.7% in 1979 to 82.7% in 2009. During this period, the proportion of far-advanced cavitary cases among pulmonary TB patients was around 2% and remained stable. This may mean that the diagnosis had come to be performed bacteriologically rather than radiologically. The proportion of bacteriologically confirmed cases among newly notified pulmonary TB patients in 2009 was studied by sex and 5-year age group. The proportion of bacteriologically confirmed cases increased with age in both male and female TB patients. In male TB patients, the proportion of cavitary cases increased in patients aged up to the end of the 50s and then decreased with age. This tendency was not observed in females. Although the proportion of cavitary cases among elderly TB patients was lower than among youths, the proportion having extensive lesions was greater than that among youths. The proportion of sputum-smear-positive cases with cavities among pulmonary TB patients aged 30-59 years was 32.9 % in male TB patients and 17.1% in female TB patients. According to occupation, this proportion was highest in "temporary workers" (52.6%) for male TB cases and "jobless/ others" (24.9%) for female TB cases, and lowest among "medical workers" in both sexes: 8.3% of male TB cases and 7.4% of female TB cases.
1 For a discussion of XDR-TB see CDC, “Extensively Drug-Resistant Tuberculosis (XDR TB)” [http://www.cdc.gov/tb/pubs/tbfactsheets/xdrtb.htm]. 2... Tuberculosis (XDR-TB): Quarantine and Isolation Kathleen S. Swendiman and Nancy Lee Jones Legislative Attorneys American Law Division Summary The...recent international saga of a traveler with XDR-TB, a drug-resistant form of tuberculosis , has placed a spotlight on existing mechanisms to contain
... prisons, or homeless shelters. If you work in hospitals or health-care settings where TB patients are likely to be seen, you should consult infection control or occupational health experts. Ask about administrative and ...
... Correctional and Detention Facilities Guidelines for Preventing the Transmission of M. TB in Health care Settings Investigation ... infection control measures in place. Documented places where transmission has occurred include crowded hospitals, prisons, homeless shelters, ...
TUBERCULOSIS www.who.int/tb & DIABETES THE DUAL EPIDEMIC OF TB AND DIABETES DEADLY LINKAGES People with ... higher risk of progressing from latent to active tuberculosis. Diabetes triples a person’s risk of developing TB. ...
Statistics on tuberculosis (TB) in foreigners have been obtained since 1998 in Japan. The number of foreign TB patients increased from 739 in 1998 to 945 in 2008. In contrast, the number of Japanese TB patients decreased during this period and hence the proportion of foreign TB patients increased from 2.1% in 1998 to 3.9% in 2008, excluding those of unknown nationality. Especially, the proportion of those aged 20-29 years increased greatly from 9.1% in 1998 to 26.3% in 2008. Although the number of nationalities was 47, the majority of patients were from China (27.7%), the Philippines (24.8%) and Korea (10.2%) in 2008. The number of foreign TB patients aged 20-29 years was 468, accounting for 49.5% of all foreign TB patients in 2008. Seventy-seven percent of foreign patients aged 20-29 years had developed TB within 5 years of entering Japan. The equivalent proportion was 49% of those aged 30-39 years and 32% of those aged 40-49 years. Regarding occupation, 39.7% of foreign patients aged 20-29 years were full-time workers, 28.6% were students and 13.7% were part-time workers.
Coscolla, Mireia; Copin, Richard; Sutherland, Jayne; Gehre, Florian; de Jong, Bouke; Owolabi, Olumuiya; Mbayo, Georgetta; Giardina, Federica; Ernst, Joel D; Gagneux, Sebastien
Pathogens that evade adaptive immunity typically exhibit antigenic variation. By contrast, it appears that although the chronic human tuberculosis (TB)-causing pathogen Mycobacterium tuberculosis needs to counter host T cell responses, its T cell epitopes are hyperconserved. Here we present an extensive analysis of the T cell epitopes of M. tuberculosis. We combined population genomics with experimental immunology to determine the number and identity of T cell epitope sequence variants in 216 phylogenetically diverse strains of M. tuberculosis. Antigen conservation is indeed a hallmark of M. tuberculosis. However, our analysis revealed a set of seven variable antigens that were immunogenic in subjects with active TB. These findings suggest that M. tuberculosis uses mechanisms other than antigenic variation to evade T cells. T cell epitopes that exhibit sequence variation may not be subject to the same evasion mechanisms, and hence vaccines that include such variable epitopes may be more efficacious.
Jensen, T O; Darley, D R; Goeman, E E; Shaw, K; Marriott, D J; Glanville, A R
Donor-derived tuberculosis (TB) is an increasingly recognized complication of solid organ transplantation. We report a case of isoniazid-resistant pulmonary TB in a lung transplant recipient. The patient acquired the infection from the lung donor who was previously empirically treated with isoniazid for latent TB. The case highlights the caveat that, while adequate treatment of latent TB with isoniazid is presumed, meticulous screening of donors is required.
Mätz-Rensing, K; Hartmann, T; Wendel, G M; Frick, J S; Homolka, S; Richter, E; Munk, M H; Kaup, F-J
Simian tuberculosis is one of the most important bacterial diseases of non-human primates. Outbreaks of tuberculosis have been reported in primate colonies almost as long as these animals have been used experimentally or kept in zoological gardens. Significant progress has been made in reducing the incidence of tuberculosis in captive non-human primates, but despite reasonable precautions, outbreaks continue to occur. The most relevant reason is the high incidence of tuberculosis (TB) amongst the human population, in which tuberculosis is regarded as an important re-emerging disease. Furthermore, many non-human primate species originate from countries with a high burden of human TB. Therefore, Mycobacterium tuberculosis remains a significant threat in animals imported from countries with high rates of human infection. We report an outbreak of tuberculosis among a group of rhesus monkeys (Macaca mulatta) living in a closed, long-term colony. The outbreak coincided with reactivation of a TB infection in a co-worker who never had direct access to the animal house or laboratories. Eleven of 26 rhesus monkeys developed classical chronic active tuberculosis with typical caseous granulomata of varying size within different organs. The main organ system involved was the lung, suggesting an aerosol route of infection. Such an outbreak has significant economic consequences due to animal loss, disruption of research and costs related to disease control. Precautionary measures must be improved in order to avoid TB in non-human primate colonies.
Hadizadeh Tasbiti, Alireza; Yari, Shamsi; Ghanei, Mostafa; Shokrgozar, Mohammad Ali; Bahrmand, Ahmadreza
Drug-resistant TB poses a major threat to control of TB worldwide. Despite progress in the detection of Multidrug-resistant TB (MDR-TB) cases, a major diagnostic gap remains: 55% of reported TB patients estimated to have MDR-TB were not detected in 2013. MDR-TB antigens were conjugated to CNBr-activated Sepharose 4B. Specific polyclonal antibodies against MDR-TB Ags were prepared in rabbits using two boosted injections of the MDR-TB antigen. The antibodies were purified and treated with susceptible TB to remove any non-specific and cross-reactive antibodies. In the present study, comparative analysis of electrophoretic pattern of different antigens of INH/RIF-resistant TB were studied for identifying protein profiles. A RIF-resistant TB antigen was shown here to have different protein profiles from INH-resistant TB isolate. The results of Western blotting analysis showed that in the RIF- and INH-resistant antigenic fractions some bands of 14.4 and 45 kDa as immunogenic were common. Moreover, four bands of RIF-resistant TB antigen fractions (16, 19, 21, and 45 KDa) and one band of INH-resistant TB (about 26 KDa) were detected as diagnostic antigens. This study suggests that the Western blot is an accurate test to survey INH- and RIF-resistant TB antigens of M. tuberculosis infection. These findings indicate that MDR-TB diagnosis (based on Ag detection) could be useful in the identification of disease stages that precede symptomatic and microbiologically positive TB, such as subclinical and incipient TB.
Houben, R M G J; Lalli, M; Sumner, T; Hamilton, M; Pedrazzoli, D; Bonsu, F; Hippner, P; Pillay, Y; Kimerling, M; Ahmedov, S; Pretorius, C; White, R G
Tuberculosis (TB) is the leading cause of death from infectious disease worldwide, predominantly affecting low- and middle-income countries (LMICs), where resources are limited. As such, countries need to be able to choose the most efficient interventions for their respective setting. Mathematical models can be valuable tools to inform rational policy decisions and improve resource allocation, but are often unavailable or inaccessible for LMICs, particularly in TB. We developed TIME Impact, a user-friendly TB model that enables local capacity building and strengthens country-specific policy discussions to inform support funding applications at the (sub-)national level (e.g. Ministry of Finance) or to international donors (e.g. the Global Fund to Fight AIDS, Tuberculosis and Malaria).TIME Impact is an epidemiological transmission model nested in TIME, a set of TB modelling tools available for free download within the widely-used Spectrum software. The TIME Impact model reflects key aspects of the natural history of TB, with additional structure for HIV/ART, drug resistance, treatment history and age. TIME Impact enables national TB programmes (NTPs) and other TB policymakers to better understand their own TB epidemic, plan their response, apply for funding and evaluate the implementation of the response.The explicit aim of TIME Impact's user-friendly interface is to enable training of local and international TB experts towards independent use. During application of TIME Impact, close involvement of the NTPs and other local partners also builds critical understanding of the modelling methods, assumptions and limitations inherent to modelling. This is essential to generate broad country-level ownership of the modelling data inputs and results. In turn, it stimulates discussions and a review of the current evidence and assumptions, strengthening the decision-making process in general.TIME Impact has been effectively applied in a variety of settings. In South Africa, it
Hoff, Soren T; Peter, Jonathan G; Theron, Grant; Pascoe, Mellissa; Tingskov, Pernille N; Aggerbeck, Henrik; Kolbus, Daniel; Ruhwald, Morten; Andersen, Peter; Dheda, Keertan
C-Tb, a novel Mycobacterium tuberculosis and 6-kDa early secretory antigenic target/10-kDa culture filtrate protein (ESAT-6/CFP-10)-specific skin test, has high specificity in bacille Calmette-Guerin-vaccinated healthy controls. However, the sensitivity of C-Tb has hitherto not been determined. The objective was to determine the sensitivity of C-Tb in patients with active tuberculosis (TB) in comparison with the tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube (QFT-GIT).C-Tb and TST were randomly administered in a double-blinded fashion to one or the other forearm in 253 patients with active TB with or without HIV co-infection. QFT-GIT testing was performed prior to skin testing.Using a receiver operating characteristic curve-derived cut-point of 5 mm, C-Tb sensitivity was similar to QFT-GIT (73.9 (95% CI 67.8-79.3) versus 75.1 (95% CI 69.3-80.2)), and similar in HIV-infected and HIV-uninfected patients (76.7 (95% CI 69.0-83.3) versus 69.5 (95% CI 59.2-78.5)). However, sensitivity was significantly diminished in HIV-infected patients with CD4 counts <100 cells·mm(-3). C-Tb and QFT-GIT combined had significantly higher sensitivity than C-Tb alone (p<0.0001). C-Tb was safe with no significant adverse events. The 5 mm cut-point corresponded to that found in the previously published specificity study (TESEC-04).C-Tb has similar sensitivity compared with QFT-GIT for the diagnosis of M. tuberculosis infection. Sensitivity was reduced only in HIV-infected patients with severe immunosuppression. Further studies in different settings are required to validate the proposed 5 mm cut-point.
... Loss Surgery? A Week of Healthy Breakfasts Shyness Tuberculosis KidsHealth > For Teens > Tuberculosis A A A What's in this article? TB ... Duration When to Call the Doctor en español Tuberculosis TB Basics Tuberculosis (also known as "TB") is ...
Tucci, Paula; González-Sapienza, Gualberto; Marin, Monica
Tuberculosis (TB) is an infectious disease caused by members of Mycobacterium tuberculosis complex. Despite the availability of effective treatments, TB remains a major public health concern in most low and middle-income countries, representing worldwide the second leading cause of death from an infectious disease. Inadequate case detection and failures to classify the disease status hamper proper TB control. The limitations of the conventional diagnostic methods have encouraged much research activities in this field, but there is still an urgent need for an accurate point of care test for active TB diagnosis. A rapid, precise, and inexpensive TB diagnostic test would allow an earlier implementation of an appropriate treatment and the reduction of disease transmission. Pathogen-derived molecules present in clinical specimens of affected patients are being validated for that purpose. This short review aims to summarize the available data regarding biomarkers derived from M. tuberculosis, and their current usage in active TB diagnosis.
Maitra, Arundhati; Danquah, Cynthia A; Scotti, Francesca; Howard, Tracey K; Kamil, Tengku K; Bhakta, Sanjib
Tuberculosis (TB) poses a grave predicament to the world as it is not merely a scientific challenge but a socio-economic burden as well. A prime cause of mortality in human due to an infectious disease; the malady and its cause, Mycobacterium tuberculosis have remained an enigma with many questions that remain unanswered. The ability of the pathogen to survive and switch between varied physiological states necessitates a protracted therapeutic regimen that exerts an excessive strain on low-resource countries. To complicate things further, there has been a significant rise of antimicrobial resistance. Existing control measures, including treatment regimens have remained fairly uniform globally for at least half a century and require reinvention. Overcoming the societal and scientific challenges requires an increase in dialog to identify key regions that need attention and effective partners with whom successful collaborations can be fostered. In this report, we explore the discussions held at the International TB Summit 2015 hosted by EuroSciCon, which served as an excellent platform for researchers to share their recent findings. Ground-breaking results require outreach to affect policy design, governance and control of the disease. Hence, we feel it is important that meetings such as these reach a wider, global audience. PMID:26151309
Burwen, D R; Seawright, M F
The Centers for Disease Control and Prevention (CDC) recommends periodic tuberculin skin testing of healthcare workers with potential exposure to Mycobacterium tuberculosis. However, many healthcare facilities have neither a system to identify workers due for their skin test nor a means of analyzing aggregate data. To illustrate some of the complexities involved in tuberculin skin test (TST) tracking and analysis, and how these might be addressed, this report describes a software package called staffTRAK-TB, developed by the CDC to facilitate surveillance of tuberculosis infection in healthcare workers. staffTRAK-TB records data for each healthcare worker, including demographic information, occupation, work location, multiple TST results, and results of evaluations to determine if clinically active tuberculosis is present. Programmed reports include lists of workers due and overdue for skin tests, and skin test conversion rates by occupation or worksite. Standardization of types of occupations and locations allows data from multiple facilities to be aggregated and compared. Data transfer to the CDC can be performed via floppy diskettes. staffTRAK-TB illustrates important issues in software structure, standardization of occupation and work-location information, relevant data items, and reports and analyses that would be useful in practice. Developing software that adequately addresses the epidemiological issues is complex, and the lessons learned may serve as a model for hospital epidemiologists, infection control personnel, occupational health personnel, and computer programmers considering software development in this area or trying to optimize their facility's TST surveillance.
Paz-Soldan, Valerie A.; Alban, Rebecca E.; Dimos Jones, Christy; Powell, Amy R.; Oberhelman, Richard A.
Introduction: Tuberculosis (TB) remains a significant public health challenge worldwide, and particularly in Peru with one of the highest incidence rates in Latin America. TB patient behavior has a direct influence on whether a patient will receive timely diagnosis and successful treatment of their illness. Objectives: The objective was to understand the complex factors that can impact TB patient health seeking behavior. Methods: In-depth interviews were conducted with adult and parents of pediatric patients receiving TB treatment (n = 43), within that group a sub-group was also co-infected with HIV (n = 11). Results: Almost all of the study participants recognized delays in seeking either their child’s or their own diagnosis of their TB symptoms. The principal reasons for treatment-seeking delays were lack of knowledge and confusion of TB symptoms, fear and embarrassment of receiving a TB diagnosis, and a patient tendency to self-medicate prior to seeking formal medical attention. Conclusion: Health promotion activities that target patient delays have the potential to improve individual patient outcomes and mitigate the spread of TB at a community level. PMID:25566523
Azman, Andrew S.; Cobelens, Frank G.; Dowdy, David W.
Background In 2013, approximately 480,000 people developed active multidrug-resistant tuberculosis (MDR-TB), while only 97,000 started MDR-TB treatment. We sought to estimate the impact of improving access to MDR-TB diagnosis and treatment, under multiple diagnostic algorithm and treatment regimen scenarios, on ten-year projections of MDR-TB incidence and mortality. Methods We constructed a dynamic transmission model of an MDR-TB epidemic in an illustrative East/Southeast Asian setting. Using approximate Bayesian computation, we investigated a wide array of potential epidemic trajectories consistent with current notification data and known TB epidemiology. Results Despite an overall projected decline in TB incidence, data-consistent simulations suggested that MDR-TB incidence is likely to rise between 2015 and 2025 under continued 2013 treatment practices, although with considerable uncertainty (median 17% increase, 95% Uncertainty Range [UR] -38% to +137%). But if, by 2017, all identified active TB patients with previously-treated TB could be tested for drug susceptibility, and 85% of those with MDR-TB could initiate MDR-appropriate treatment, then MDR-TB incidence in 2025 could be reduced by 26% (95% UR 4–52%) relative to projections under continued current practice. Also expanding this drug-susceptibility testing and appropriate MDR-TB treatment to treatment-naïve as well as previously-treated TB cases, by 2020, could reduce MDR-TB incidence in 2025 by 29% (95% UR 6–55%) compared to continued current practice. If this diagnosis and treatment of all MDR-TB in known active TB cases by 2020 could be implemented via a novel second-line regimen with similar effectiveness and tolerability as current first-line therapy, a 54% (95% UR 20–74%) reduction in MDR-TB incidence compared to current-practice projections could be achieved by 2025. Conclusions Expansion of diagnosis and treatment of MDR-TB, even using current sub-optimal second-line regimens, is expected
Yan, Isabel; Bendavid, Eran; Korenromp, Eline L.
Introduction Antiretroviral therapy (ART) reduces mortality in patients with active tuberculosis (TB), but the population-level relationship between ART coverage and TB mortality is untested. We estimated the reduction in population-level TB mortality that can be attributed to increasing ART coverage across 41 high HIV-TB burden countries. Methods We compiled TB mortality trends between 1996 and 2011 from two sources: (1) national program-reported TB death notifications, adjusted for annual TB case detection rates, and (2) WHO TB mortality estimates. National coverage with ART, as proportion of HIV-infected people in need, was obtained from UNAIDS. We applied panel linear regressions controlling for HIV prevalence (5-year lagged), coverage of TB interventions (estimated by WHO and UNAIDS), gross domestic product per capita, health spending from domestic sources, urbanization, and country fixed effects. Results Models suggest that that increasing ART coverage was followed by reduced TB mortality, across multiple specifications. For death notifications at 2 to 5 years following a given ART scale-up, a 1% increase in ART coverage predicted 0.95% faster mortality rate decline (p = 0.002); resulting in 27% fewer TB deaths in 2011 alone than would have occurred without ART. Based on WHO death estimates, a 1% increase in ART predicted a 1.0% reduced TB death rate (p<0.001), and 31% fewer deaths in 2011. TB mortality was higher at higher HIV prevalence (p<0.001), but not related to coverage of isoniazid preventive therapy, cotrimoxazole preventive therapy, or other covariates. Conclusion This econometric analysis supports a substantial impact of ART on population-level TB mortality realized already within the first decade of ART scale-up, that is apparent despite variable-quality mortality data. PMID:27536864
Sharma, Surendra K.; Vashishtha, Richa; Chauhan, L. S.; Sreenivas, V.; Seth, Divya
Background There are currently two tests for diagnosing latent tuberculosis infection (LTBI); TST and IGRA. However, it is still unclear that which one of these tests performs better in high TB-burden settings. Methods 1511 household contacts of pulmonary TB patients were enrolled to compare the performance of TST and IGRA for LTBI. At baseline all participant underwent testing for IGRA [QuantiFERON-TB® Gold In-tube (QFT-GIT) assay] and TST [2 tuberculin unit (TU), purified protein derivative (PPD), RT23, Staten Serum Institute (SSI), Copenhagen, Denmark]. All the household contacts were followed-up for two years for incident TB cases. Results Active TB was diagnosed in 76 household contacts at an incidence rate of 2.14 per 1000 person-years. Both, TST [Hazard Ratio (HR): 1.14, 95% confidence interval (CI): 0.72–1.79, p = 0.57], as well as QFT-GIT assay (HR: 1.66, 95% CI: 0.97–2.84, p = 0.06) results at baseline were not significantly associated with subsequent development of active TB among household contacts of pulmonary TB patients. Conclusion Neither TST nor IGRA predicted subsequent development of active TB among household contacts of pulmonary TB patients during follow-up. However, keeping in view the cost, and other logistics, TST remains the most preferred method for LTBI diagnosis in resource-limited, high TB-burden settings. PMID:28060926
... Loss Surgery? A Week of Healthy Breakfasts Shyness Tuberculosis KidsHealth > For Teens > Tuberculosis Print A A A What's in this article? ... Duration When to Call the Doctor en español Tuberculosis TB Basics Tuberculosis (also known as "TB") is ...
Burgos, J. L.; Kahn, J. G.; Strathdee, S. A.; Valencia-Mendoza, A.; Bautista-Arredondo, S.; Laniado-Laborin, R.; Castañeda, R.; Deiss, R.; Garfein, R. S.
SUMMARY OBJECTIVE To assess the cost-effectiveness of screening for latent tuberculosis infection (LTBI) using a commercially available detection test and treating individuals at high risk for human immunodeficiency virus (HIV) infection in a middle-income country. DESIGN We developed a Markov model to evaluate the cost per LTBI case detected, TB case averted and quality-adjusted life year (QALY) gained for a cohort of 1000 individuals at high risk for HIV infection over 20 years. Baseline model inputs for LTBI prevalence were obtained from published literature and cross-sectional data from tuberculosis (TB) screening using QuantiFERON®-TB Gold In-Tube (QFT-GIT) testing among sex workers and illicit drug users at high risk for HIV recruited through street outreach in Tijuana, Mexico. Costs are reported in 2007 US dollars. Future costs and QALYs were discounted at 3% per year. Sensitivity analyses were performed to evaluate model robustness. RESULTS Over 20 years, we estimate the program would prevent 78 cases of active TB and 55 TB-related deaths. The incremental cost per case of LTBI detected was US$730, cost per active TB averted was US$529 and cost per QALY gained was US$108. CONCLUSIONS In settings of endemic TB and escalating HIV incidence, targeting LTBI screening and treatment among high-risk groups may be highly cost-effective. PMID:19723375
Dodor, Emmanuel Atsu; Kelly, Shona; Neal, Keith
Health professionals are in a power category within any social setting so when they identify and label diseases with negative attributes, it can be recognised by society with discriminatory consequences for individuals affected in the community. This article reports how activities of health professionals, as perceived and construed by community members can be a basis of stigmatisation of patients with tuberculosis (TB) in society. One hundred individual interviews and 22 focus groups were held with community members and patients with TB, and the generated data analysed using the grounded theory techniques and procedures. Through examination of the words and statements of the participants, five inter-related ways by which activities of health professionals may expose patients with TB to stigmatisation in the community were identified: isolation and exclusionary practices; behaviours of health professionals towards patients with TB; public health discourse; food safety and hygiene practices and prohibition of full burial rites to those who died from TB. These activities are mirrored in the attitudes and behaviours of community members, and often become the basis of stigmatisation of individuals affected by TB in society. This may considerably contribute to diagnostic delay and low case finding in Ghana. Because, for fear of stigmatisation, community members who may be experiencing symptoms suggestive of TB may fail to go to the hospital. The stigma attached to TB in society may also contribute to the poor adherence to treatment seen among patients with TB in Ghana. To help to improve case finding and defaulter rate, the TB control programme should organise regular refresher courses in TB control and management for health professionals, and address the fear of infection by developing a national guidelines on how to prevent transmission of TB to health professionals within the hospital setting.
Mulholland, Claire V; Ruthe, Ali; Cursons, Ray T; Durrant, Robert; Karalus, Noel; Coley, Kathryn; Bower, James; Permina, Elizabeth; Coleman, Megan J; Roberts, Sally A; Arcus, Vickery L; Cook, Gregory M; Aung, Htin Lin
Despite New Zealand being a low-tuberculosis (TB) burden country, there are disproportionately high rates of TB in particular populations. Here, we report a rapid molecular diagnosis of the Mycobacterium tuberculosis Rangipo strain responsible for the largest recurring TB cluster in New Zealand.
Phillips, Patrick P J; Fletcher, Helen A; Abubakar, Ibrahim; Lipman, Marc C I; McHugh, Timothy D
In this interview, we talk to leading tuberculosis (TB) experts from University College London and the London School of Hygiene and Tropical Medicine about the current challenges in TB research. The video of this interview is available here: https://www.youtube.com/watch?v=75Die7MQBec&feature=youtu.be . The video can also be downloaded via Additional file 1.
Blankley, Simon; Graham, Christine M.; Turner, Jacob; Berry, Matthew P. R.; Bloom, Chloe I.; Xu, Zhaohui; Pascual, Virginia; Banchereau, Jacques; Chaussabel, Damien; Breen, Ronan; Santis, George; Blankenship, Derek M.; Lipman, Marc; O’Garra, Anne
Background Mycobacterium tuberculosis infection is a leading cause of infectious death worldwide. Gene-expression microarray studies profiling the blood transcriptional response of tuberculosis (TB) patients have been undertaken in order to better understand the host immune response as well as to identify potential biomarkers of disease. To date most of these studies have focused on pulmonary TB patients with gene-expression profiles of extra-pulmonary TB patients yet to be compared to those of patients with pulmonary TB or sarcoidosis. Methods A novel cohort of patients with extra-pulmonary TB and sarcoidosis was recruited and the transcriptional response of these patients compared to those with pulmonary TB using a variety of transcriptomic approaches including testing a previously defined 380 gene meta-signature of active TB. Results The 380 meta-signature broadly differentiated active TB from healthy controls in this new dataset consisting of pulmonary and extra-pulmonary TB. The top 15 genes from this meta-signature had a lower sensitivity for differentiating extra-pulmonary TB from healthy controls as compared to pulmonary TB. We found the blood transcriptional responses in pulmonary and extra-pulmonary TB to be heterogeneous and to reflect the extent of symptoms of disease. Conclusions The transcriptional signature in extra-pulmonary TB demonstrated heterogeneity of gene expression reflective of symptom status, while the signature of pulmonary TB was distinct, based on a higher proportion of symptomatic individuals. These findings are of importance for the rational design and implementation of mRNA based TB diagnostics. PMID:27706152
Macovei, Lilia; Kanunfre, Kelly; Dhiman, Rakesh; Restrepo, Blanca I.; Zarate, Izelda; Pino, Paula A.; Mora-Guzman, Francisco; Fujiwara, Ricardo T.; Michel, Gerd; Kashino, Suely S.
The development of an accurate antigen detection assay for the diagnosis of active tuberculosis (TB) would represent a major clinical advance. Here, we demonstrate that the Mycobacterium tuberculosis Rv1681 protein is a biomarker for active TB with potential diagnostic utility. We initially identified, by mass spectroscopy, peptides from the Rv1681 protein in urine specimens from 4 patients with untreated active TB. Rabbit IgG anti-recombinant Rv1681 detected Rv1681 protein in lysates and culture filtrates of M. tuberculosis and immunoprecipitated it from pooled urine specimens from two TB patients. An enzyme-linked immunosorbent assay formatted with these antibodies detected Rv1681 protein in unconcentrated urine specimens from 11/25 (44%) TB patients and 1/21 (4.8%) subjects in whom TB was initially clinically suspected but then ruled out by conventional methods. Rv1681 protein was not detected in urine specimens from 10 subjects with Escherichia coli-positive urine cultures, 26 subjects with confirmed non-TB tropical diseases (11 with schistosomiasis, 5 with Chagas' disease, and 10 with cutaneous leishmaniasis), and 14 healthy subjects. These results provide strong validation of Rv1681 protein as a promising biomarker for TB diagnosis. PMID:23390284
Active tuberculosis (TB) has a greater burden of TB bacilli than latent TB and acts as an infection source for contacts. Latent tuberculosis infection (LTBI) is the state in which humans are infected with Mycobacterium tuberculosis without any clinical symptoms, radiological abnormality, or microbiological evidence. TB is transmissible by respiratory droplet nucleus of 1–5 µm in diameter, containing 1–10 TB bacilli. TB transmission is affected by the strength of the infectious source, infectiousness of TB bacilli, immunoresistance of the host, environmental stresses, and biosocial factors. Infection controls to reduce TB transmission consist of managerial activities, administrative control, engineering control, environmental control, and personal protective equipment provision. However, diagnosis and treatment for LTBI as a national TB control program is an important strategy on the precondition that active TB is not missed. Therefore, more concrete evidences for LTBI management based on clinical and public perspectives are needed. PMID:27790271
Satoh, Ken; Motomiya, Masakichi
Tuberculosis control law was enacted in 1951 and has been the basis for the management of TB cases over the long post-war period. This law has legalized the use of public founds for the treatment of TB patients for the first time and has provided the authentic basis for mandatory hospitalization, routine health examination, vaccination, notification and registration of TB cases. However, this law was abrogated in 2001 and was joined to the comprehensive infectious diseases control law, in order to facilitate a prophylactic measure against TB infection and to protect human rights of TB patients. Concurrently the medical care system and the formalities connected to hospitalization treatment of TB patients were reviewed. The purpose of the present overview is to explain how TB cases are managed under the newly-enacted law.
Background Immigrants to Germany and their children are at particular risk for tuberculosis (TB). Methods 35 Patients (10 male/25 female aged 2 - 59 years (median 33 years) originating mostly from high incidence countries in Asia (19 [54.3%]) in Africa (14 [40.0%] and East Europe (2 [5.7%]), attended at the Tropical Medicine unit were analysed. Results Primary clinical presentation was most frequently lymphadenitis (13 [37.1%]). other organs involved included bones (7 [20.0%]), central nervous system (5 [14.3%]), urogenital organs (3 [8.6%]), lung (3 [8.6%]), mediastinum, (2 [5.7%]) and abdomen (2 [5.7%]). ESR was abnormal in 21/28 (75.0%), CRP in 20/35 (57.1%), and protein electrophoresis in 22/26 (84.6%) cases. The tuberculin skin test was strongly positive in all 15 cases where the test had been performed. Tuberculosis interferon gamma release assay (TB-IGRA) was positive in all 35 cases (100%). PCR for nucleic acids of Mycobacterium (M.) tuberculosis complex was positive in only 7/20 (35.0%) cases. M. tuberculosis was identified in 32/35 (91.4%), M. bovis in 2 (5.7%) cases. 1 case was diagnosed clinically. All patients were negative for HIV. Typical histopathology was seen in the 29 cases, where biopsies had been taken. Chest-X-ray did not reveal specific pulmonary lesions in the majority of cases (22/35 [62.9%]). Diagnosis of TB was mostly delayed (4 to 299 weeks, [median 8]). The most frequent primary suspicion was a malignancy (17/35 [48.6%]) while TB was initially suspected in 5 cases only. Diagnosis of TB is impeded by its multifaceted presentation especially in immigrants. PMID:22024436
Maitra, Arundhati; Bhakta, Sanjib
World TB Day commemorates Dr Robert Koch's first announcement on March 24, 1882, that the bacterium Mycobacterium tuberculosis is the causative agent of tuberculosis. Currently, the event comprises of several conferences, meetings and activities held all over the world with the singular intention of raising public awareness about the global health emergency. In spite of having discovered the etiological agent of tuberculosis more than a century ago, a sizeable population still contract the disease every year and fall prey to it. In 2012, an estimated 8.6 million people developed the disease with 1.3 million succumbing to it. The number of TB deaths in children is unacceptably large, given that most are preventable. However, the challenge appears to be shifting toward attempts to control the rise and spread of the drug resistant variants of the microbe. To achieve this, a concerted effort from academia, clinical practice, and industry has been put forth. The TB Summit 2014 attempted to raise awareness as well as bring together experts involved in different aspects of tuberculosis research to help establish a more collective approach to battle this age-old disease.
Piccazzo, Riccardo; Paparo, Francesco; Garlaschi, Giacomo
In this systematic review we evaluate the role of chest radiography (CXR) in the diagnostic flow chart for tuberculosis (TB) infection, focusing on latent TB infection (LTBI) in patients requiring medical treatment with biological drugs. In recent findings, patients scheduled for immunomodulatory therapy with biologic drugs are a group at risk of TB reactivation and, in such patients, detection of LTBI is of great importance. CXR for diagnosis of pulmonary TB has good sensitivity, but poor specificity. Radiographic diagnosis of active disease can only be reliably made on the basis of temporal evolution of pulmonary lesions. In vivo tuberculin skin test and ex vivo interferon-γ release assays are designed to identify development of an adaptive immune response, but not necessarily LTBI. Computed tomography (CT) is able to distinguish active from inactive disease. CT is considered a complementary imaging modality to CXR in the screening procedure to detect past and LTBI infection in specific subgroups of patients who have increased risk for TB reactivation, including those scheduled for medical treatment with biological drugs.
Whole-Genome Sequences of Mycobacterium tuberculosis TB282 and TB284, a Widespread and a Unique Strain, Respectively, Identified in a Previous Study of Tuberculosis Transmission in Central Los Angeles, California, USA
ABSTRACT We report here the genome sequences of two Mycobacterium tuberculosis clinical isolates previously identified in central Los Angeles, CA, in the 1990s using a PacBio platform. Isolate TB282 represents a large-cluster strain that caused 27% of the tuberculosis cases, while TB284 represents a strain that caused disease in only one patient. PMID:28082486
Prevalence of post-traumatic stress symptoms and associated factors in tuberculosis (TB), TB retreatment and/or TB-HIV co-infected primary public health-care patients in three districts in South Africa.
Peltzer, Karl; Naidoo, Pamela; Matseke, Gladys; Louw, Julia; McHunu, Gugu; Tutshana, Bomkazi
High rates of tuberculosis (TB) and TB/HIV co-infection is often linked with mental health issues such as post-traumatic stress disorder (PTSD) symptoms, which is further associated with poor health outcomes. In a country such as South Africa where rates of these infectious diseases are high, it is concerning that there is limited/no data on prevalence rates of mental disorders such as PTSD and its associated factors. Therefore, the aim of this study was to establish the prevalence of PTSD symptoms and associated factors in TB, TB retreatment and/or TB-HIV co-infected primary public health-care patients in three districts in South Africa. Brief screening self-report tools were used to measure: PTSD symptoms, psychological distress (anxiety and depression) and alcohol misuse. Other relevant measures, such as adherence to medication, stressful life events and sexual risk-taking behaviours, were obtained through structured questions. A total of 4900 public primary care adult patients from clinics in high TB burden districts from three provinces in South Africa participated. All the patients screened positive for TB (either new or retreatment cases). The prevalence of PTSD symptoms was 29.6%. Patients who screened positive for PTSD symptoms and psychological distress were more likely to be on antidepressant medication. Factors that predicted PTSD symptoms were poverty, residing in an urban area, psychological distress, suicide attempt, alcohol and/or drug use before sex, unprotected sex, TB-HIV co-infected and the number of other chronic conditions. Health-care systems should be strengthened to improve delivery of mental health care, by focusing on existing programmes and activities, such as those which address the prevention and treatment of TB and HIV.
Beste, Dany JV; Hooper, Tracy; Stewart, Graham; Bonde, Bhushan; Avignone-Rossa, Claudio; Bushell, Michael E; Wheeler, Paul; Klamt, Steffen; Kierzek, Andrzej M; McFadden, Johnjoe
Background An impediment to the rational development of novel drugs against tuberculosis (TB) is a general paucity of knowledge concerning the metabolism of Mycobacterium tuberculosis, particularly during infection. Constraint-based modeling provides a novel approach to investigating microbial metabolism but has not yet been applied to genome-scale modeling of M. tuberculosis. Results GSMN-TB, a genome-scale metabolic model of M. tuberculosis, was constructed, consisting of 849 unique reactions and 739 metabolites, and involving 726 genes. The model was calibrated by growing Mycobacterium bovis bacille Calmette Guérin in continuous culture and steady-state growth parameters were measured. Flux balance analysis was used to calculate substrate consumption rates, which were shown to correspond closely to experimentally determined values. Predictions of gene essentiality were also made by flux balance analysis simulation and were compared with global mutagenesis data for M. tuberculosis grown in vitro. A prediction accuracy of 78% was achieved. Known drug targets were predicted to be essential by the model. The model demonstrated a potential role for the enzyme isocitrate lyase during the slow growth of mycobacteria, and this hypothesis was experimentally verified. An interactive web-based version of the model is available. Conclusion The GSMN-TB model successfully simulated many of the growth properties of M. tuberculosis. The model provides a means to examine the metabolic flexibility of bacteria and predict the phenotype of mutants, and it highlights previously unexplored features of M. tuberculosis metabolism. PMID:17521419
Smith, Jason E.; Simkulet, Michelle D.; Gutin, Alexander; Gutin, Alexy; Bardarov, Savco; Jacobs, William R., Jr.; Castracane, James; Tang, Oliver; Riska, Paul
Tuberculosis (TB) remains the leading cause of death in the world from a single infectious disease, and the threat is becoming more critical with the spread of multi-drug resistant Tuberculosis (MDR-TB). TB detection, and susceptibility testing for drug resistant strain identification, is advancing with the development of Luciferase Reporter Mycobacteriophages (LRM). LRM will emit visible light at very low intensity when in the presence of live mycobacteria cells such as Tuberculosis strains. InterScience, Inc., together with its collaboration, is developing a highly sensitive, real-time digital detection system for the analysis of luminescent assays. Recent advances in system sensitivity, design, and implementation, as well as preliminary results of the development of individual test cartridges, will be presented. The ultimate goal of this work is to provide a versatile luminescence detection tool for widespread research and clinical applications.
Wares, Fraser; Falzon, Dennis
Each year there are about nine million new cases of tuberculosis (TB) in the world and over one million people die of the disease. The emergence of resistance to the drugs that are used to treat TB threaten to undo much of the progress achieved in controlling it in recent decades. In some countries, up to one third or more of TB cases have multidrug-resistant TB (MDR-TB; combined resistance to at least isoniazid and rifampicin), requiring a much longer and toxic treatment than that suffices for other TB patients. Countries have committed to achieve universal access to care for MDR-TB for their populations by 2015. In this article, we use national data collected by the World Health Organization (WHO) to assess global progress in detection (against WHO estimates) and treatment of MDR-TB. Over one half of all the world's MDR-TB patients are concentrated in three countries: India, China, and the Russian Federation. In 2012, about 78,753 TB cases were reported to have been started on MDR-TB treatment, about 25% of the estimated MDR-TB case load in the world. Only 48% of over 35,000 MDR-TB patients started on treatment in 2010 were reported to have completed their treatment successfully. The global MDR-TB targets for 2015 will not be achieved unless barriers to the expansion of reliable diagnosis and effective treatment of MDR-TB are not urgently overcome in many countries. New diagnostics and medicines will be required to speed up this drive within the new WHO global strategy which now looks well beyond 2015.
Annual reports of tuberculosis (TB) statistics in Japan have been compiled mainly using the output of the database obtained through the nationwide computerized tuberculosis surveillance system which has been operated since 1987. This system has been revised several times, with the latest revision conducted in 2007 when much new information was added. Therefore, a plan was drawn up to provide TB epidemiological statistics in Japan on "Kekkaku" and a series of ten reports was already issued as "TB Annual Report 2008". This is the first report of a new series for "TB Annual Report 2009". The report can be summarized as follows. The TB notification (incidence) rate fell below 20 per 100,000 in 2007 and continued to decline, reaching 19.0 in 2009. However, 24,170 TB patients were newly notified in 2009. For sputum smear positive pulmonary TB, the patient count was 9,675 with an incidence rate of 7.6 per 100,000 in 2009. Since June 2007, it has been legally compulsory to notify latent TB infections (LTBI) requiring treatment; the number in 2009 was 4119 cases.
Pang, Yu; Dong, Haiyan; Tan, Yaoju; Deng, Yunfeng; Cai, Xingshan; Jing, Hui; Xia, Hui; Li, Qiang; Ou, Xichao; Su, Biyi; Li, Xuezheng; Zhang, Zhiying; Li, Junchen; Zhang, Jiankang; Huan, Shitong; Zhao, Yanlin
New diagnostic methods have provided a promising solution for rapid and reliable detection of drug-resistant TB strains. The aim of this study was to evaluate the performance of the MeltPro TB assay in identifying multidrug-resistant (MDR-) and extensively drug-resistant tuberculosis (XDR-TB) patients from sputum samples. The MeltPro TB assay was evaluated using sputum samples from 2057 smear-positive TB patients. Phenotypic Mycobacterial Growth Indicator Tube (MGIT) 960 drug susceptibility testing served as a reference standard. The sensitivity of the MeltPro TB assay was 94.2% for detecting resistance to rifampicin and 84.9% for detecting resistance to isoniazid. For second-line drugs, the assay showed a sensitivity of 83.3% for ofloxacin resistance, 75.0% for amikacin resistance, and 63.5% for kanamycin resistance. However, there was a significant difference for detecting kanamycin resistance between the two pilot sites in sensitivity, which was 53.2% in Guangdong and 81.5% in Shandong (P = 0.015). Overall, the MeltPro TB assay demonstrated good performance for the detection of MDR- and XDR-TB, with a sensitivity of 86.7% and 71.4%, respectively. The MeltPro TB assay is an excellent alternative for the detection of MDR- and XDR-TB cases in China, with high accuracy, short testing turn-around time, and low unit price compared with other tests.
Atre, Sachin R; Murray, Megan B
Multidrug-resistant tuberculosis (MDR-TB) challenges TB control efforts because of delays in diagnosis plus its long-term treatment which has toxic effects. Of TB high-incidence countries, India carries the highest burden of MDR-TB cases. We describe policy issues in India concerning MDR-TB diagnosis and management in a careful review of the literature including a systematic review of studies on the prevalence of MDR-TB. Of 995 articles published during 2001-2016 and retrieved from the PubMed, only 20 provided data on the population prevalence of MDR-TB. We further reviewed and describe diagnostic criteria and treatment algorithms in use and endorsed by the Revised National TB Control Program of India. We discuss problems encountered in treating MDR-TB patients with standardized regimens. Finally, we provide realistic suggestions for policymakers and program planners to improve the management and control of MDR-TB in India.Journal of Public Health Policy advance online publication, 6 May 2016; doi:10.1057/jphp.2016.14.
Ekins, Sean; Casey, Allen C.; Roberts, David; Parish, Tanya; Bunin, Barry A.
The search for compounds active against Mycobacterium tuberculosis is reliant upon high throughput screening (HTS) in whole cells. We have used Bayesian machine learning models which can predict anti-tubercular activity to filter an internal library of over 150,000 compounds prior to in vitro testing. We used this to select and test 48 compounds in vitro; 11 were active with MIC values ranging from 0.4 µM to 10.2 µM, giving a high hit rate of 22.9%. Among the hits, we identified several compounds belonging to the same series including five quinolones (including ciprofloxacin), three molecules with long aliphatic linkers and three singletons. This approach represents a rapid method to prioritize compounds for testing that can be used alongside medicinal chemistry insight and other filters to identify active molecules. Such models can significantly increase the hit rate of HTS, above the usual 1% or lower rates seen. In addition, the potential targets for the 11 molecules were predicted using TB Mobile and clustering alongside a set of over 740 molecules with known M. tuberculosis target annotations. These predictions may serve as a mechanism for prioritizing compounds for further optimization. PMID:24440548
Dobler, Claudia Caroline
In recent years, there has been renewed interest in screening for active tuberculosis (TB), also called active case-finding (ACF), as a possible means to achieve control of the global TB epidemic. ACF aims to increase the detection of TB, in order to diagnose and treat patients with TB earlier than if they had been diagnosed and treated only at the time when they sought health care because of symptoms. This will reduce or avoid secondary transmission of TB to other people, with the long-term goal of reducing the incidence of TB. Here, the history of screening for active TB, current screening practices, and the role of TB-diagnostic tools are summarized and the literature on cost-effectiveness of screening for active TB reviewed. Cost-effectiveness analyses indicate that community-wide ACF can be cost-effective in settings with a high incidence of TB. ACF among close TB contacts is cost-effective in settings with a low as well as a high incidence of TB. The evidence for cost-effectiveness of screening among HIV-infected persons is not as strong as for TB contacts, but the reviewed studies suggest that the intervention can be cost-effective depending on the background prevalence of TB and test volume. None of the cost-effectiveness analyses were informed by data from randomized controlled trials. As the results of randomized controlled trials evaluating different ACF strategies will become available in future, we will hopefully gain a better understanding of the role that ACF can play in achieving global TB control. PMID:27418848
Chung-Delgado, Kocfa; Guillen-Bravo, Sonia; Revilla-Montag, Alejandro; Bernabe-Ortiz, Antonio
Background An increase in multidrug-resistant tuberculosis (MDR-TB) cases is evident worldwide. Its management implies a complex treatment, high costs, more toxic anti-tuberculosis drug use, longer treatment time and increased treatment failure and mortality. The aims of this study were to compare mortality between MDR and drug-susceptible cases of tuberculosis, and to determine risk factors associated with mortality among MDR-TB cases. Methods and Results A retrospective cohort study was performed using data from clinical records of the National Strategy for Prevention and Control of Tuberculosis in Lima, Peru. In the first objective, MDR-TB, compared to drug-susceptible cases, was the main exposure variable and time to death, censored at 180 days, the outcome of interest. For the second objective, different variables obtained from clinical records were assessed as potential risk factors for death among MDR-TB cases. Cox regression analysis was used to determine hazard ratios (HR) and 95% confidence intervals (95%CI). A total of 1,232 patients were analyzed: mean age 30.9 ±14.0 years, 60.0% were males. 61 patients (5.0%) died during treatment, whereas the MDR-TB prevalence was 19.2%. MDR-TB increased the risk of death during treatment (HR = 7.5; IC95%: 4.1–13.4) when compared to presumed drug-susceptible cases after controlling for potential confounders. Education level (p = 0.01), previous TB episodes (p<0.001), diabetes history (p<0.001) and HIV infection (p = 0.04) were factors associated with mortality among MDR-TB cases. Conclusions MDR-TB is associated with an increased risk of death during treatment. Lower education, greater number of previous TB episodes, diabetes history, and HIV infection were independently associated with mortality among MDR-TB cases. New strategies for appropriate MDR-TB detection and management should be implemented, including drug sensitivity tests, diabetes and HIV screening, as well as guarantee for a complete adherence to
Kali, Paula B N; Gray, Glenda E; Violari, Avy; Chaisson, Richard E; McIntyre, James A; Martinson, Neil A
Tuberculosis (TB) is the preeminent manifestation of HIV infection and has become a leading cause of maternal mortality and morbidity in high HIV-prevalence settings. Active TB in pregnant women has potentially serious consequences for fetuses and newborns. In Soweto, South Africa, there is a more than 90% uptake of voluntary counseling and HIV testing during routine antenatal care, and almost one third of pregnant women are HIV-infected. The posttest counseling session of the prevention of mother-to-child transmission program provides an opportunity to screen HIV-infected pregnant women for TB. In this study, 370 HIV-infected pregnant women were screened for symptoms of active TB by lay counselors at the posttest counseling session. If symptomatic, they were referred to nurses who investigated them further. Eight women were found to have previously undiagnosed, smear-negative, culture-confirmed TB (2160/100,000). The mean CD4 count in those with active TB compared to those without TB was 276 x 10(6) cells per liter vs 447 x 10(6) cells per liter (P = 0.051). Symptoms most associated with active TB were hemoptysis and fever. We conclude that rates of TB in HIV-infected pregnant women are high, and screening for TB during routine antenatal care should be implemented in high HIV-prevalence settings.
Ohkado, Akihiro; Williams, Gini; Ishikawa, Nobukatsu; Shimouchi, Akira; Simon, Carter
The tuberculosis (TB) notification in Osaka City has been persistently high compared with other urban areas in Japan. Although the TB notification in Greater London has kept much lower level compared with that in Osaka City, it has been also persistently high compared with other urban areas in the UK. Nonetheless, the contexts of the two cities relating TB control programme as well as the epidemiological situation greatly vary; there must be some lessons to be learnt from each other to improve each TB control programme to tackle against TB more effectively. Comparing the epidemiological situation of TB in both cities, it is obvious that Osaka City suffers TB more than Greater London in terms of the TB notification rate. Concerning the context of the TB control programme, Osaka City has centralised approach with strong local government commitment; Greater London, on the other hand, has an approach that is greatly fragmented but coordinated through voluntary TB Networks. This paper aims to draw some constructive and practical lessons from Greater London TB control management for further improvement of Osaka City TB control management through literature review and interview to health professionals. TB epidemiology in Greater London shows distinct features in the extent of TB in new entrants and TB co-infected with HIV in comparison with those in Osaka City. TB epidemiology in Osaka City is to a great extent specifically related to homeless people whereas in Greater London, this relationship occurs to a lesser extent. Both areas have relatively high TB-notification rates compared with national figures, and they have "TB hot spots" where remarkably high TB-notification rates exist. TB control in Greater London is characterised with decentralised and devolved services to local government health authorities supplemented with co-ordinating bodies across sectors as well as across Greater London. Sector-wide TB Network as well as London TB Group (LTBG) and London TB Nurses
Essential facts Tuberculosis (TB) is an infection caused by a bacterium, mycobacterium tuberculosis. While it can affect any part of the body, only pulmonary TB is infectious. According to the charity TB Alert, there were 5,758 cases of TB in the UK in 2015 and 39% of them were in London. This represented a fall from a peak of 8,919 cases in 2011. Left untreated, TB is life-threatening, but is usually curable with antibiotics. The sooner it is diagnosed and treated, the better, both for the person's health and in preventing them from passing the infection on to others.
Essential facts Tuberculosis (TB) is an infection caused by a bacterium, mycobacterium tuberculosis. While it can affect any part of the body, only pulmonary TB is infectious. According to the charity TB Alert, there were 5,758 cases of TB in the UK in 2015 and 39% of them were in London. This represented a fall from a peak of 8,919 cases in 2011. Left untreated, TB is life-threatening, but is usually curable with antibiotics. The sooner it is diagnosed and treated, the better, both for the person's health and in preventing them from passing the infection on to others.
Liu, Miaomiao; Grkovic, Tanja; Zhang, Lixin; Liu, Xueting; Quinn, Ronald J
The development of new antibiotics effective against all strains of tuberculosis (TB) is needed. To evaluate the potential of marine microbe-derived natural products as anti-TB leads, we analyzed and compared the physico-chemical properties of 39 current TB drugs and candidates against 60 confirmed mycobacteria-active natural products. We showed that anti-TB natural products sourced from marine microbes have a large overlap with TB drug-like space. A model to predict potential anti-TB drugs is proposed.
Background In 2004, tuberculosis (TB) was responsible for 2.5% of global mortality (among men 3.1%; among women 1.8%) and 2.2% of global burden of disease (men 2.7%; women 1.7%). The present work portrays accumulated evidence on the association between alcohol consumption and TB with the aim to clarify the nature of the relationship. Methods A systematic review of existing scientific data on the association between alcohol consumption and TB, and on studies relevant for clarification of causality was undertaken. Results There is a strong association between heavy alcohol use/alcohol use disorders (AUD) and TB. A meta-analysis on the risk of TB for these factors yielded a pooled relative risk of 2.94 (95% CI: 1.89-4.59). Numerous studies show pathogenic impact of alcohol on the immune system causing susceptibility to TB among heavy drinkers. In addition, there are potential social pathways linking AUD and TB. Heavy alcohol use strongly influences both the incidence and the outcome of the disease and was found to be linked to altered pharmacokinetics of medicines used in treatment of TB, social marginalization and drift, higher rate of re-infection, higher rate of treatment defaults and development of drug-resistant forms of TB. Based on the available data, about 10% of the TB cases globally were estimated to be attributable to alcohol. Conclusion The epidemiological and other evidence presented indicates that heavy alcohol use/AUD constitute a risk factor for incidence and re-infection of TB. Consequences for prevention and clinical interventions are discussed. PMID:19961618
Nourzad, Susan; Jenkins, Helen E.; Milstein, Meredith; Mitnick, Carole D.
SUMMARY Background Multidrug-resistant tuberculosis (MDR-TB) burden estimates are based on incomplete, infrequently updated data among a limited pool of cases: notified or incident, pulmonary TB patients. Methods Using WHO data reported by 217 countries/territories in 2014, we calculated MDR-TB burdens among prevalent TB cases and compared these with estimates among incident and notified TB patients. We also compared treatment coverage across estimates. Findings Among prevalent TB patients globally in 2014, we estimate that 555,545 (95% credible bounds: 499,340–617,391) MDR-TB cases occurred. This is 85% more than the 300,000 estimated among notified cases, and 16% more than the 480,000 among incident cases. Only 20% of MDR-TB cases among prevalent—compared to 37% of MDR-TB among notified—TB patients had access to MDR-TB treatment. Applying prior estimates, only 10% of MDR-TB cases will have successful outcomes. Interpretation Estimates based on likely-to-be-diagnosed cases of MDR-TB overlook a significant proportion of morbidity, mortality, and transmission: that occur in undiagnosed, untreated, prevalent TB patients. Still likely underestimating the true disease burden, MDR-TB among patients with prevalent TB represents a closer approximation of disease burden than currently reported indicators. Progress toward elimination—or control—depends on policies guided by a more complete representation of the disease burden. PMID:28157458
Lin, Qingqing; Zhou, Mengying; Xu, Zongkai; Khanniche, Asma; Shen, Hao; Wang, Chuan
Bacillus Calmette-Guerin (BCG) has failed in complete control of tuberculosis (TB), thus, novel tuberculosis vaccines are urgently needed. We have constructed several TB vaccine candidates, which are characterized by the use of Listeria ivanovii (LI) strain as an antigen delivery vector. Two L. ivanovii attenuated recombinant strains L. ivanovii△actAplcB-Rv0129c and L. ivanovii△actAplcB-Rv3875 were successfully screened. Results from genome PCR and sequencing showed that the Mycobacterium tuberculosis antigen gene cassette coding for Ag85C or ESAT-6 protein respectively had been integrated into LI genome downstream of mpl gene. Western blot confirmed the secretion of Ag85C or ESAT-6 protein from the recombinant LI strains. These two recombinant strains showed similar growth curves as wide type strain in vitro. In vivo, they transiently propagated in mice spleen and liver, and induced specific CD8(+) IFN-γ secretion. Therefore, in this paper, two novel LI attenuated strains expressing specific TB antigens were successfully constructed. The promising growth characteristics in mice immune system and the capability of induction of IFN-γ secretion make them of potential interest for development of TB vaccines.
Noro, Jeffrey C.; Barrows, Louis R.; Gideon, Osia G.; Ireland, Chris M.; Koch, Michael; Matainaho, Teatulohi; Piskaut, Pius; Pond, Christopher D.; Bugni, Tim S.
Tuberculosis has become a major health problem, in particular with the emergence of extremely drug resistant tuberculosis (XDRTB). In our search for new therapeutic leads against TB, we isolated a new triterpene (1) from the plant Rhus taitensis collected in Papua New Guinea. Tetrahydroxysqualene (1) was isolated using bioassay-guided fractionation of the methanolic extract of R. taitensis leaves and twigs. The structure of tetrahydroxysqualene (1) was elucidated on the basis of HRESIMS and 1D and 2D NMR spectra. Tetrahydroxysqualene (1) exhibited anti–tuberculosis activity with an MIC of 10.0 μg/mL while showing only modest cytotoxicity. PMID:18710283
MDR-TB is known to be man-made-disease. Inappropriate treatment of tuberculosis is responsible for the development of MDR-TB. MDR-TB is often accompanied with the immunosuppression of the host. Given that we are unable to develop another potent anti-TB drug in near future, immunotherapy directed at combating immunosuppression and enhancing the host's own immune response is an attractive approach to supplement conventional chemotherapy for MDR-TB. Patients with AIDS and patients with abnormalities of macrophage function have frequent problems with TB. This is suggesting that the host defenses involved in protection against mycobacteria include T-cell and monocyte/macrophage functions. That is cell-mediated immunity. Diverse cytokines are known to play an important role in anti-TB cell-mediated immunity, including IL-2, IL-12, IL-18 and IFN-gamma. Various animal experiments are indicating that administration of these cytokine (s) did recover the suppressed immunity and rescued the host from death by tuberculous infection. However, we have to keep it in mind that the results obtained from animal model of mycobacterial infection on the study of pathogenesis and immune responses in TB is not always applicable to the understanding of human TB. Clinical trial of inhalation therapy with IFN-gamma showed some improvement for drug-resistant TB. Cytokine treatment, however, often gave some deleterious side effects such as high fever, malaise, general edema and even the death of the host. Clinical trials with M. vaccae have been extensively conducted by UK group. The mechanisms underlying its possible therapeutic action remain to be clarified, but when administered at an appropriate dose, it has been shown to elicit a strong Th1 immune response. From the practical view point of immunotherapy for TB, surrogate markers of disease eradication and protective immunity are urgently required. Such markers would facilitate clinical trials by providing early evidence that test
Sebina, Ismail; Biraro, Irene A; Dockrell, Hazel M; Elliott, Alison M; Cose, Stephen
Accurate biomarkers of Mycobacterium tuberculosis infection activity would significantly improve early diagnosis, treatment and management of M. tuberculosis infection. We hypothesised that circulating B-lymphocytes may be useful biomarkers of tuberculosis (TB) infection status in highly TB-endemic settings. Ex-vivo and in-vitro mycobacteria-specific B-cell ELISPOT assays were used to examine the plasmablast (PB) and memory B-cell (MBC) responses in the peripheral blood of adult, healthy, community controls (n = 151) and of active TB patients (n = 48) living in Uganda. Frequencies of mycobacteria-specific PBs were markedly higher in active TB patients compared to healthy controls, and, conversely, MBCs were markedly higher in the healthy controls compared to active TB patients. In addition, the community controls with evidence of latent TB infection had higher peripheral blood PB and MBC responses than those without evidence of TB infection. These data demonstrate that peripheral blood B-cell responses are differentially modulated during latent and active M. tuberculosis infection, and suggest that the PB to MBC ratio may be a useful biomarker of TB infection activity.
Brust, Belinda; Lecoufle, Mélanie; Tuaillon, Edouard; Dedieu, Luc; Canaan, Stéphane; Valverde, Viviane; Kremer, Laurent
Background New diagnosis tests are urgently needed to address the global tuberculosis (TB) burden and to improve control programs especially in resource-limited settings. An effective in vitro diagnostic of TB based on serological methods would be regarded as an attractive progress because immunoassays are simple, rapid, inexpensive, and may offer the possibility to detect cases missed by standard sputum smear microscopy. However, currently available serology tests for TB are highly variable in sensitivity and specificity. Lipolytic enzymes have recently emerged as key factors in lipid metabolization during dormancy and/or exit of the non-replicating growth phase, a prerequisite step of TB reactivation. The focus of this study was to analyze and compare the potential of four Mycobacterium tuberculosis lipolytic enzymes (LipY, Rv0183, Rv1984c and Rv3452) as new markers in the serodiagnosis of active TB. Methods Recombinant proteins were produced and used in optimized ELISA aimed to detect IgG and IgM serum antibodies against the four lipolytic enzymes. The capacity of the assays to identify infection was evaluated in patients with either active TB or latent TB and compared with two distinct control groups consisting of BCG-vaccinated blood donors and hospitalized non-TB individuals. Results A robust humoral response was detected in patients with active TB whereas antibodies against lipolytic enzymes were infrequently detected in either uninfected groups or in subjects with latent infection. High specifity levels, ranging from 93.9% to 97.5%, were obtained for all four antigens with sensitivity values ranging from 73.4% to 90.5%, with Rv3452 displaying the highest performances. Patients with active TB usually exhibited strong IgG responses but poor IgM responses. Conclusion These results clearly indicate that the lipolytic enzymes tested are strongly immunogenic allowing to distinguish active from latent TB infections. They appear as potent biomarkers providing high
Veeser, Peggy Ingram; Smith, Phillip Karl; Handy, Barry; Martin, Sharon R.
Detecting and managing "Mycobacterium tuberculosis" (TB) infection in a health-science center population is a clinical dilemma. Tuberculin skin tests are still the preferred method for detecting present or past infection of TB. The authors discuss the performance of whole blood interferon gamma release assay test commercially known as…
Sali, Michela; Buonsenso, Danilo; Goletti, Delia; D’Alfonso, Pamela; Zumbo, Antonella; Fadda, Giovanni; Sanguinetti, Maurizio; Delogu, Giovanni; Valentini, Piero
Objectives To evaluate the accuracy of the QuantiFERON-TB Gold assay (QFT-IT) in children with suspected active or latent TB infection (LTBI). Methods A retrospective study was conducted on 621 children (0–14 years old) evaluated for TB infection or disease. Following clinical assessment, children were tested with the QFT-IT assay. Results Among the 140 active TB suspects, we identified 19 cases of active disease. The overall sensitivity for active TB was 87.5%, ranging from 62.5% in children 25–36 months old to 100% in children older than 49 months. The overall specificity for active TB was 93.6%. Among the 481 children tested for LTBI screening, 38 scored positive and all but 2 had at least one risk factor for TB infection. Among the 26 children with indeterminate results, bacterial, viral or fungal pneumonia were later diagnosed in 11 (42.3%) cases and non-TB related extra-pulmonary infections in 12 (46.1%). Conclusions Our results indicate that the children's response to QFT-IT associates to active TB and risk factors for LTBI. Moreover, we show that mitogen response is also found in children of 1 year of age, providing support for QFT-IT use also in young children. PMID:26439935
Sirinak, Chawin; Kittikraisak, Wanitchaya; Pinjeesekikul, Duangporn; Charusuntonsri, Pricha; Luanloed, Phinai; Srisuwanvilai, La-ong; Nateniyom, Sriprapa; Akksilp, Somsak; Likanonsakul, Sirirat; Sattayawuthipong, Wanchai; Burapat, Channawong; Varma, Jay K
Background The occurrence of tuberculosis (TB), human immunodeficiency virus (HIV), and viral hepatitis infections in the same patient poses unique clinical and public health challenges, because medications to treat TB and HIV are hepatotoxic. We conducted an observational study to evaluate risk factors for HBsAg and/or anti-HCV reactivity and to assess differences in adverse events and TB treatment outcomes among HIV-infected TB patients. Methods Patients were evaluated at the beginning, during, and at the end of TB treatment. Blood samples were tested for aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (BR), complete blood count, and CD4+ T lymphocyte cell count. TB treatment outcomes were assessed at the end of TB treatment according to international guidelines. Results Of 769 enrolled patients, 752 (98%) had serologic testing performed for viral hepatitis: 70 (9%) were reactive for HBsAg, 237 (31%) for anti-HCV, and 472 (63%) non-reactive for both markers. At the beginning of TB treatment, 18 (26%) patients with HBsAg reactivity had elevated liver function tests compared with 69 (15%) patients non-reactive to any viral marker (p = 0.02). At the end of TB treatment, 493 (64%) were successfully treated. Factors independently associated with HBsAg reactivity included being a man who had sex with men (adjusted odds ratio [AOR], 2.1; 95% confidence interval [CI], 1.1–4.3) and having low TB knowledge (AOR, 1.8; CI, 1.0–3.0). Factors most strongly associated with anti-HCV reactivity were having injection drug use history (AOR, 12.8; CI, 7.0–23.2) and living in Bangkok (AOR, 15.8; CI, 9.4–26.5). The rate of clinical hepatitis and death during TB treatment was similar in patients HBsAg reactive, anti-HCV reactive, both HBsAg and anti-HCV reactive, and non-reactive to any viral marker. Conclusion Among HIV-infected TB patients living in Thailand, markers of viral hepatitis infection, particularly hepatitis C virus infection, were
Yaesoubi, Reza; Cohen, Ted
The global tuberculosis (TB) control plan has historically emphasized passive case finding (PCF) as the most practical approach for identifying TB suspects in high burden settings. The success of this approach in controlling TB depends on infectious individuals recognizing their symptoms and voluntarily seeking diagnosis rapidly enough to reduce onward transmission. It now appears, at least in some settings, that more intensified case-finding (ICF) approaches may be needed to control TB transmission; these more aggressive approaches for detecting as-yet undiagnosed cases obviously require additional resources to implement. Given that TB control programs are resource constrained and that the incremental yield of ICF is expected to wane over time as the pool of undiagnosed cases is depleted, a tool that can help policymakers to identify when to implement or suspend an ICF intervention would be valuable. In this article, we propose dynamic case-finding policies that allow policymakers to use existing observations about the epidemic and resource availability to determine when to switch between PCF and ICF to efficiently use resources to optimize population health. Using mathematical models of TB/HIV coepidemics, we show that dynamic policies strictly dominate static policies that prespecify a frequency and duration of rounds of ICF. We also find that the use of a diagnostic tool with better sensitivity for detecting smear-negative cases (e.g., Xpert MTB/RIF) further improves the incremental benefit of these dynamic case-finding policies.
Ntoumi, Francine; Kaleebu, Pontiano; Macete, Eusebio; Mfinanga, Sayoki; Chakaya, Jeremiah; Yeboah-Manu, Dorothy; Bates, Matthew; Mwaba, Peter; Maeurer, Markus; Petersen, Eskild; Zumla, Alimuddin
Tuberculosis (TB) remains a global emergency, with an estimated 9.6 million new TB cases worldwide reported in 2014. Twenty-eight percent of these cases were in the World Health Organization (WHO) Africa Region, where the annual case detection rate was 281 per 100000 population-more than double the global average of 133 per 100000. Of the 9.6 million people who developed TB, an estimated 1.2 million (12%) were HIV-positive, and the Africa Region accounted for 74% of these cases. Three million people with TB remain undiagnosed and untreated. Globally, an estimated 480000 had multidrug-resistant TB (MDR-TB). Whilst of the African countries, only South Africa has reported a high prevalence of MDR-TB, it is likely that all of Sub-Saharan Africa has an unreported high load of drug-resistant TB. Tragically, in 2014, only 48% of individuals diagnosed with MDR-TB had successful treatment and an estimated 190000 people died of MDR-TB. Of the global TB funding gap of US$ 0.8 billion, the largest funding gap was in the Africa Region, amounting to US$ 0.4 billion in 2015. The MDR-TB pandemic in particular now threatens to devastate entire regions and may fundamentally alter the life-expectancy and demographic profile of many countries in Sub-Saharan Africa. The theme designated for this year's World TB Day, March 24, 2016, is 'Unite to End TB'. From the Africa Region, there is an urgent need to seriously address the political, economic, and social factors that influence host-Mycobacterium tuberculosis interactions and result in disease. Recent political and funder initiatives that provide renewed hope for the alleviation of Africa's TB and TB/HIV problems are discussed.
Delva, Guesly J.; Fort, Dumesle St.
Background. Haiti has the highest tuberculosis (TB) prevalence in the Americas with 254 cases per 100,000 persons. Case detection relies on passive detection and TB services in many regions suffer from poor diagnostic and clinical resources. Methods. Mache Chache (“Go and Seek”) was a TB REACH Wave 3 funded TB case finding project in Port-au-Prince between July 2013 and September 2014, targeting four intervention areas with insufficient TB diagnostic performance. Results. Based on a verbal symptom screen emphasizing the presence of cough, the project identified 11,150 (11.75%) of all screened persons as TB subjects and 2.67% as smear-positive (SS+) TB cases. Enhanced case finding and strengthening of laboratory services led to a 59% increase in bacteriologically confirmed cases in the evaluation population. In addition, smear grades dropped significantly, suggesting earlier case detection. Xpert® MTB/RIF was successfully introduced and improved TB diagnosis in HIV-infected, smear-negative clinic patients, but not in HIV-negative, smear-negative TB suspects in the community. However, the number needed to screen for one additional SS+ case varied widely between clinic and community screening activities. Conclusion. Enhanced and active TB case finding in Haiti can improve TB diagnosis and care. However, screening algorithms have to be tailored to individual settings, necessitating long-term commitment. PMID:27668093
Shekhawat, Seema D; Purohit, Hemant J; Taori, Girdhar M; Daginawala, Hatim F; Kashyap, Rajpal S
The diagnosis of a latent tuberculosis infection (LTBI) is of the utmost concern. The available tests, the tuberculin skin test (TST) and the Quantiferon-TB Gold test (QFT-G) cannot discriminate between active TB and LTBI. Therefore, the aim of the study is to identify new biomarkers that can discriminate between active TB and LTBI and can also assess the risk of the individual developing active TB. In total, 55 blood samples were collected, of which 10 samples were from the active TB infection group, 10 were from the high-risk exposure group, 23 were from the low-risk exposure group, and 12 were from healthy controls living in a non-TB endemic area. A panel of heat shock proteins (Hsps), including host Hsp25, Hsp60, Hsp70, and Hsp90 and Mycobacterium tuberculosis (MTB) Hsp16, were evaluated in all of the collected samples using ELISA. The levels of the host Hsp(s) (Hsp25, Hsp60, Hsp70 and Hsp90) and MTB Hsp16 were significantly (p<0.05) elevated in the active TB group compared to the high-risk exposure group, the low-risk exposure group and the control group. Notably, the levels of the same panel of Hsp(s) were elevated in the high-risk exposure group compared to the low-risk exposure group. On follow-up, out of the 10 high-risk exposure participants, 3 converted into active TB, indicating that this group has the highest risk of developing TB. Thus, the evaluated panel of Hsp(s) can discriminate between LTBI and active TB. They can also identify individuals who are at the highest risk of developing active TB. Because they can be rapidly detected, Hsp(s) have an edge over the existing diagnostic tools for LTBI. The evaluation of these proteins will be useful in designing better diagnostic methods for LTBI.
Evaluation of the treatment outcome by the cohort analysis method is an important part of tuberculosis (TB) control. In the Japanese TB surveillance system, the treatment outcome is automatically classified by computer according to a pre-set algorithm, so the treatment outcome is evaluated very rigidly. In the case of new sputum smear positive pulmonary TB cases (n = 8,999) newly notified in 2008, the patients' treatment outcomes based on the annual report 2009 database were as follows: "success," which combined "cured" and "completed," was 47.7%, "died" was 19.1%, "failed" was 1.1%, "defaulted" was 3.8%, "transferred out" was 2.8%, "on treatment after 12 months" was 11.8% and "not evaluated" was 13.6%. In addition to evaluation of the treatment outcome by the cohort method, the proportion of deaths was observed among all forms of TB patients (n = 24,571) who were newly registered in 2008. In total, 17.3% of all forms of TB cases died within one year after the beginning of treatment. The proportion corresponding to this was 23.7% for new sputum smear positive pulmonary TB and 23.5% for re-treatment sputum smear positive pulmonary TB. Among the new sputum smear positive pulmonary TB patients (n = 2,136) who died within one year after the beginning of treatment, 37.0% of them died within one month after the beginning of treatment, 51.6% died within two months and 61.9% died within three months.
Domingos, Mirian Pereira; Caiaffa, Waleska Teixeira; Colosimo, Enrico Antônio
This non-concurrent cohort study aims to identify predictors of tuberculosis mortality in a large population database in Brazil. Tuberculosis, death, and TB/HIV cases were validated respectively from the tuberculosis surveillance (SINAN/TB), mortality (SIM), and SINAN/AIDS databases for a five-year period. Analysis included proportional hazard models with relative risk estimates. Out of 5,451 individuals reported with tuberculosis, 320 (5.9%) died (incidence and mortality rates of 98.6 and 12.2/100 thousand inhabitants, respectively). After adjustment, relative risk of dying from tuberculosis was 9.8 for individuals>50 years of age; 9.0 for TB/HIV co-infection; 3.0 for mixed TB clinical presentation; and 2.0 for treatment dropout. In the multivariate model, using cases with HIV/AIDS, all adjusted predictors lost significance except mixed clinical presentation (RR 1.9; 1.1-3.1). TB/HIV co-infection is an important predictor of TB mortality. However, among individuals without HIV/AIDS, mortality is still highly associated with older age, mixed clinical forms, and treatment dropout.
[Human resource capacity building on TB laboratory work for TB control program--through the experience of international TB laboratory training course for TB control at the Research Institute of Tuberculosis, JATA, Japan].
Fujiki, Akiko; Kato, Seiya
The international training course on TB laboratory work for national tuberculosis program (NTP) has been conducted at the Research Institute of Tuberculosis since 1975 funded by Japan International Cooperation Agency in collaboration with WHO Western Pacific Regional Office. The aim of the course is to train key personnel in TB laboratory field for NTP in resource-limited countries. The course has trained 265 national key personnel in TB laboratory service from 57 resource-limited countries in the last 33 years. The number of participants trained may sound too small in the fight against the large TB problem in resource-limited countries. However, every participant is playing an important role as a core and catalyst for the TB control program in his/her own country when they were back home. The curriculum is composed of technical aspects on TB examination, mainly sputum microscopy in addition since microscopy service is provided at many centers that are deployed in a widely spread area, the managerial aspect of maintaining quality TB laboratory work at the field laboratory is another component of the curriculum. Effective teaching methods using materials such as artificial sputum, which is useful for panel slide preparation, and technical manuals with illustrations and pictures of training procedure have been developed through the experience of the course. These manuals are highly appreciated and widely used by the front line TB workers. The course has also contributed to the expansion of EQA (External Quality Assessment) system on AFB microscopy for the improvement of the quality of TB laboratory service of NTP. The course is well-known for not only having a long history, but also for its unique learning method emphasizing "Participatory Training", particularly for practicum sessions to master the skills on AFB microscopy. The method in learning AFB microscopy, which was developed by the course, was published as a training manual by IUATLD, RIT and USAID. As it is
Khanapur, Manjulatha; Alvala, Mallika; Prabhakar, Maddela; Shiva Kumar, K; Edwin, R K; Sri Saranya, P S V K; Patel, Raj Kumar; Bulusu, Gopalakrishnan; Misra, P; Pal, Manojit
Mycobacterium tuberculosis chorismate mutase (MtbCM) catalyzes the rearrangement of chorismate to prephenate in the shikimate biosynthetic pathway to form the essential amino acids, phenylalanine and tyrosine. Two genes encoding chorismate mutase have been identified in Mtb. The secretory form,∗MtbCM (encoded by Rv1885c) is assumed to play a key role in pathogenesis of tuberculosis. Also, the inhibition of MtbCM may hinder the supply of nutrients to the organism. Indeed, the existence of chorismate mutase (CM) in bacteria, fungi and higher plants but not in human and low sequence homology among known CM makes it an interesting target for the discovery of anti-tubercular agents. The present article mainly focuses on the recent developments in the structure, function and inhibition of MtbCM. The understanding of various aspects of MtbCM as presented in the current article may facilitate the design and subsequent chemical synthesis of new inhibitors against ∗MtbCM, that could lead to the discovery and development of novel and potent anti-tubercular agents in future.
Luetkemeyer, Anne F; Kendall, Michelle A; Wu, Xingye; Lourenço, Maria Cristina; Jentsch, Ute; Swindells, Susan; Qasba, Sarojini S; Sanchez, Jorge; Havlir, Diane V; Grinsztejn, Beatriz; Sanne, Ian M; Firnhaber, Cynthia
Limited performance data from line probe assays (LPAs), nucleic acid tests used for the rapid diagnosis of tuberculosis (TB), nontuberculosis mycobacteria (NTM), and Mycobacterium tuberculosis drug resistance are available for HIV-infected individuals, in whom paucibacillary TB is common. In this study, the strategy of testing sputum with GenoType MTBDRplus (MTBDR-Plus) and GenoType Direct LPA (Direct LPA) was compared to a gold standard of one mycobacterial growth indicator tube (MGIT) liquid culture. HIV-positive (HIV(+)) individuals with suspected TB from southern Africa and South America with <7 days of TB treatment had 1 sputum specimen tested with Direct LPA, MTBDR-Plus LPA, smear microscopy, MGIT, biochemical identification of mycobacterial species, and culture-based drug-susceptibility testing (DST). Of 639 participants, 59.3% were MGIT M. tuberculosis culture positive, of which 276 (72.8%) were acid-fast bacillus (AFB) smear positive. MTBDR-Plus had a sensitivity of 81.0% and a specificity of 100%, with sensitivities of 44.1% in AFB smear-negative versus 94.6% in AFB smear-positive specimens. For specimens that were positive for M. tuberculosis by MTBDR-Plus, the sensitivity and specificity for rifampin resistance were 91.7% and 96.6%, respectively, and for isoniazid (INH) they were 70.6% and 99.1%. The Direct LPA had a sensitivity of 88.4% and a specificity of 94.6% for M. tuberculosis detection, with a sensitivity of 72.5% in smear-negative specimens. Ten of 639 MGIT cultures grew Mycobacterium avium complex or Mycobacterium kansasii, half of which were detected by Direct LPA. Both LPA assays performed well in specimens from HIV-infected individuals, including in AFB smear-negative specimens, with 72.5% sensitivity for M. tuberculosis identification with the Direct LPA and 44.1% sensitivity with MTBDR-Plus. LPAs have a continued role for use in settings where rapid identification of INH resistance and clinically relevant NTM are priorities.
Adane, Kelemework; Spigt, Mark; Johanna, Laturnus; Noortje, Dorscheidt; Abera, Semaw Ferede; Dinant, Geert-Jan
Introduction Although awareness is an important component in tuberculosis (TB) control, we do not know how much Ethiopian prisoners know about TB. This study assessed the level of knowledge, attitudes, and practices (KAP) of prisoners about TB in eight northern Ethiopian prisons. Methods Data were collected cross-sectionally from 615 prisoners using a standardized questionnaire between March and May 2016. The outcome variables were defined considering the basic elements about TB. Results Out of 615 prisoners, only 37.7% mentioned bacteria as a cause of TB while 21.7% related TB to exposure to cold wind. Eighty-eight per cent correctly mentioned the aerial route of TB transmission and 27.3% had perceived stigma towards TB. The majority (63.7%) was not aware of the possibility of getting multi-drug-resistant strains when they would not adhere to treatment. Overall, only 24% knew the basic elements about TB, 41% had favorable attitudes, and 55% had a good practice. Prisoners who were urban residents were generally more knowledgeable than rural residents (adjusted OR = 2.16; 95% CI = 1.15–4.06). Illiterates were found to be less knowledgeable (adjusted OR = 0.17; 95% CI = 0.06–0.46), less likely to have a favorable attitude (adjusted OR = 0.31; 95% CI = 0.15–0.64), and less good practice (adjusted OR = 0.35; 95% CI = 0.18–0.69). Significant differences were also observed between the different study prisons. Conclusions Knowledge of prisoners regarding the cause of TB and consequences of non-adherence to TB treatment was low. Knowledge on the transmission, symptoms, and prevention was fairly high. Health education interventions, focused on the cause and the translation of the knowledge to appropriate practices, are needed in all the study prisons. Special attention should be given to less educated prisoners, and to prisons with a high number of prisoners and those in remote areas. PMID:28358877
Lemma, Fitsum A.; Mekonnen, Daniel A.; Alemu, Zelalem E.; Kelkay, Tessema Z.
Bovine tuberculosis (bTB) infection is generally correlated with individual cattle’s age, sex, body condition, and with husbandry practices such as herd composition, cattle movement, herd size, production system and proximity to wildlife—including bTB maintenance hosts. We tested the correlation between those factors and the prevalence of bTB, which is endemic in Ethiopia’s highland cattle, in the Afar Region and Awash National Park between November 2013 and April 2015. A total of 2550 cattle from 102 herds were tested for bTB presence using the comparative intradermal tuberculin test (CITT). Data on herd structure, herd movement, management and production system, livestock transfer, and contact with wildlife were collected using semi-structured interviews with cattle herders and herd owners. The individual overall prevalence of cattle bTB was 5.5%, with a herd prevalence of 46%. Generalized Linear Mixed Models with a random herd-effect were used to analyse risk factors of cattle reactors within each herd. The older the age of the cattle and the lower the body condition the higher the chance of a positive bTB test result, but sex, lactation status and reproductive status were not correlated with bTB status. At herd level, General Linear Models showed that pastoral production systems with transhumant herds had a higher bTB prevalence than sedentary herds. A model averaging analysis identified herd size, contact with wildlife, and the interaction of herd size and contact with wildlife as significant risk factors for bTB prevalence in cattle. A subsequent Structural Equation Model showed that the probability of contact with wildlife was influenced by herd size, through herd movement. Larger herds moved more and grazed in larger areas, hence the probability of grazing in an area with wildlife and contact with either infected cattle or infected wildlife hosts increased, enhancing the chances for bTB infection. Therefore, future bTB control strategies in cattle in
Sánchez-Soto, Eduardo; Ponce-Ramos, Rosa; Hernández-Gutiérrez, Rodolfo; Gutiérrez-Ortega, Abel; Álvarez, Angel H; Martínez-Velázquez, Moisés; Absalón, Angel E; Ortiz-Lazareno, Pablo; Limón-Flores, Alberto; Estrada-Chávez, Ciro; Herrera-Rodríguez, Sara E
Bovine colostrum contains compounds, which provide passive immune protection from mother to newborn calves. Little is known about cytokine levels and their role in bovine colostrum. Moreover, the capacity of bovine colostrum cells to mount specific immune responses after natural exposure to bovine tuberculosis (bTB) antigens in dairy herds has not been studied, thus far. The purpose of this study was to identify biomarkers for bTB infection measurable in bovine colostrum. The present study reveals that isolated-immune colostrum cells can mount a specific immune response against bTB antigens, by measuring the novo IFN-γ release in cell culture. We found that IFN-γ levels in the responders (Bov(+)) to bTB antigen were higher than in non-responders (Bov(-)). On the other hand, proinflammatory cytokines contained in colostrum's whey were tested in Tuberculin Skin Test (TST) reactor (TST(+)) and non-reactor (TST(-)) animals to assess their potential role as biomarker. We observed that IFN-γ levels were lower or undetectable, as opposed to IL4 levels were measurable, the TNF-α level was higher in TST(-) than TST(+), while IL-6 levels showed the opposite reaction and with no statistical significance. Moreover, IL-1α mRNA expression levels were higher in colostrum mononuclear cells (CMC) in Bov(+) cattle. Collectively, these data suggest that the differential expression of pro and anti-inflammatory cytokines could have relevant value to diagnose bTB in cattle.
TB Elimination Tuberculosis: General Information What is TB? Tuberculosis (TB) is a disease caused by germs that are spread from person ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination CS227840_A What Does a Positive Test ...
Yi, Lina; Sasaki, Yuka; Nagai, Hideaki; Ishikawa, Satoru; Takamori, Mikio; Sakashita, Kentaro; Saito, Takefumi; Fukushima, Kiyoyasu; Igarashi, Yuriko; Aono, Akio; Chikamatsu, Kinuyo; Yamada, Hiroyuki; Takaki, Akiko; Mori, Toru; Mitarai, Satoshi
Performance of interferon-γ (IFN-γ) release assays still needs to be improved. The data on the performance of QuantiFERON-TB Gold Plus (QFT-Plus), a new-generation of QFT assay are limited. This study evaluated the diagnostic performance of QFT-Plus, and compared to that of QuantiFERON-TB Gold In-Tube (QFT-GIT). Blood samples were collected from 162 bacteriologically confirmed tuberculosis (TB) patients and 212 Mycobacterium tuberculosis-uninfected volunteers; these samples were then tested with QFT-GIT and QFT-Plus. The IFN-γ concentration of QFT-Plus was lower than that of QFT-GIT in TB patients (p < 0.001). Receiver operating characteristic curves were compared between QFT-GIT and QFT-Plus. Both assays showed area under the curve values over 0.99 without significant difference. Using the conventional cut-off (0.35 IU/mL) for QFT-GIT, QFT-Plus had a lower sensitivity of 91.1% compared to 96.2% (p = 0.008) at its optimum cut-off (0.168 IU/mL) with the same specificity. Moreover, IFN-γ values were significantly reduced with age in QFT-GIT (p = 0.035) but not in QFT-Plus. The diagnostic performance of QFT-Plus was as accurate as that of QFT-GIT despite a lack of TB7.7 antigen and despite the decrease in quantitative values. However, the cut-off value for QFT-Plus should be considered independently from that of QFT-GIT to obtain the best sensitivity without compromising specificity. PMID:27470684
Yi, Lina; Sasaki, Yuka; Nagai, Hideaki; Ishikawa, Satoru; Takamori, Mikio; Sakashita, Kentaro; Saito, Takefumi; Fukushima, Kiyoyasu; Igarashi, Yuriko; Aono, Akio; Chikamatsu, Kinuyo; Yamada, Hiroyuki; Takaki, Akiko; Mori, Toru; Mitarai, Satoshi
Performance of interferon-γ (IFN-γ) release assays still needs to be improved. The data on the performance of QuantiFERON-TB Gold Plus (QFT-Plus), a new-generation of QFT assay are limited. This study evaluated the diagnostic performance of QFT-Plus, and compared to that of QuantiFERON-TB Gold In-Tube (QFT-GIT). Blood samples were collected from 162 bacteriologically confirmed tuberculosis (TB) patients and 212 Mycobacterium tuberculosis-uninfected volunteers; these samples were then tested with QFT-GIT and QFT-Plus. The IFN-γ concentration of QFT-Plus was lower than that of QFT-GIT in TB patients (p < 0.001). Receiver operating characteristic curves were compared between QFT-GIT and QFT-Plus. Both assays showed area under the curve values over 0.99 without significant difference. Using the conventional cut-off (0.35 IU/mL) for QFT-GIT, QFT-Plus had a lower sensitivity of 91.1% compared to 96.2% (p = 0.008) at its optimum cut-off (0.168 IU/mL) with the same specificity. Moreover, IFN-γ values were significantly reduced with age in QFT-GIT (p = 0.035) but not in QFT-Plus. The diagnostic performance of QFT-Plus was as accurate as that of QFT-GIT despite a lack of TB7.7 antigen and despite the decrease in quantitative values. However, the cut-off value for QFT-Plus should be considered independently from that of QFT-GIT to obtain the best sensitivity without compromising specificity.
Tsuyuguchi, Kazunari; Nagai, Hideaki; Ogawa, Kenji; Matsumoto, Tomoshige; Morimoto, Kozo; Takaki, Akiko; Mitarai, Satoshi
Xpert MTB/RIF is an automated nucleic acid amplification test (NAT) that can detect the presence of Mycobacterium tuberculosis complex (MTC) in clinical specimens as well as rifampicin (RIF) resistance resulting from rpoB mutation. Despite its high sensitivity and specificity for diagnosing tuberculosis (TB) with or without RIF resistance, the clinical performance of the test is variable. In this study, we evaluated the performance of Xpert MTB/RIF in a setting of moderate TB burden and high medical resources. A total of 427 sputum specimens were obtained from 237 suspected TB cases. Of these, 159 were identified as active TB, while the other 78 were non-TB diseases. The overall sensitivity and specificity of MTC detection by Xpert MTB/RIF using culture results as a reference were 86.8% [95% confidence interval (CI): 81.8%-90.6%] and 96.8% (95% CI: 93.1%-98.5%), respectively. Among MTC-positive culture specimens, Xpert MTB/RIF positivity was 95.2% (95% CI: 91.2%-97.5%) in smear-positive and 44.7% (95% CI 30.1-60.3) in smear-negative specimens. Xpert MTB/RIF was similar to other NATs (TaqMan MTB and TRCRapid M.TB) in terms of performance. Xpert MTB/RIF detected 25 RIF-resistant isolates as compared to 22 with the mycobacterial growth indicator tube antimicrobial susceptibility testing system, yielding a sensitivity of 100% (95% CI: 85.1%-100%) and specificity of 98.3% (95% CI: 95.1%-99.4%). These results indicate that although sensitivity in smear-negative/culture-positive specimens was relatively low, Xpert MTB/RIF is a useful diagnostic tool for detecting TB and RIF resistance even in settings of moderate TB burden.
Barrows, Louis R.; Powan, Emma; Pond, Christopher D.; Matainaho, Teatulohi
An ethyl acetate extract of bark from Evodia elleryana produced significant growth inhibition of Mycobacterium tuberculosis at concentrations only minimally inhibitory to human T cells. The crude extract yielded 95% inhibition of TB at 50 μg/ml. The crude extract yielded 29 % growth inhibition of human T-cells in culture at that concentration. PMID:17350179
Igari, Hidetoshi; Watanabe, Akira; Ichimura, Yasunori; Sakurai, Takayuki; Taniguchi, Toshibumi; Ishiwada, Naruhiko
QuantiFERON-TB gold in-tube has been used for screening latent tuberculosis infection in newly employed health care workers in Japan. There have been a few studies concerning quality control. We retrospectively analysed QuantiFERON-TB gold in-tube results in a hospital in Japan. Interferon-γ values in three blood collection tubes for QuantiFERON-TB gold in-tube were analysed in association with the positivity rate. The data set consisted of health care workers aged 20-29 years during the 7 years between 2010 and 2016. The yearly QuantiFERON-TB gold in-tube positivity rate was 0.9%, 16.4%, 3.0%, 39.3%, 2.8%, 0.9% and 1.5%, and was extremely high in 2011 and 2013. The interferon-γ values in the tuberculosis antigen tube were elevated in these two years, as indicated by higher median and wider interquartile range. The interferon-γ value in the negative control tube was also higher in 2011. The higher interferon-γ values in collection tubes (tuberculosis antigen tube and/or negative control tube) resulted in higher QuantiFERON-TB gold in-tube positivity rate. The distribution of interferon-γ in tuberculosis antigen tube and negative control tube, as evaluated by median and interquartile range, proved to be an effective index for the quality control of QuantiFERON-TB gold in-tube.
Domínguez, J; Boettger, E C; Cirillo, D; Cobelens, F; Eisenach, K D; Gagneux, S; Hillemann, D; Horsburgh, R; Molina-Moya, B; Niemann, S; Tortoli, E; Whitelaw, A; Lange, C
The emergence of drug-resistant strains of Mycobacterium tuberculosis is a challenge to global tuberculosis (TB) control. Although culture-based methods have been regarded as the gold standard for drug susceptibility testing (DST), molecular methods provide rapid information on mutations in the M. tuberculosis genome associated with resistance to anti-tuberculosis drugs. We ascertained consensus on the use of the results of molecular DST for clinical treatment decisions in TB patients. This document has been developed by TBNET and RESIST-TB groups to reach a consensus about reporting standards in the clinical use of molecular DST results. Review of the available literature and the search for evidence included hand-searching journals and searching electronic databases. The panel identified single nucleotide mutations in genomic regions of M. tuberculosis coding for katG, inhA, rpoB, embB, rrs, rpsL and gyrA that are likely related to drug resistance in vivo. Identification of any of these mutations in clinical isolates of M. tuberculosis has implications for the management of TB patients, pending the results of in vitro DST. However, false-positive and false-negative results in detecting resistance-associated mutations in drugs for which there is poor or unproven correlation between phenotypic and clinical drug resistance complicate the interpretation. Reports of molecular DST results should therefore include specific information on the mutations identified and provide guidance for clinicians on interpretation and on the choice of the appropriate initial drug regimen.
Camacho-Corona, María Del Rayo; Ramírez-Cabrera, Mónica A; Santiago, Omar González-; Garza-González, Elvira; Palacios, Isidoro de Paz; Luna-Herrera, Julieta
Tuberculosis (TB) kills about 3 million people per year worldwide. Furthermore, TB is an infectious disease associated with HIV patients, and there is a rise in multidrug-resistant TB (MDR-TB) cases around the world. There is a need for new anti-TB agents. The study evaluated the antimycobacterial activity of nine plants used in Mexican traditional medicine to treat tuberculosis and other respiratory diseases. Nasturtium officinale showed the best activity (MIC = 100 microg/mL) against the sensitive Mycobacterium tuberculosis. The following plants were active also but at 200 microg/mL: Citrus sinensis, Citrus aurantifolia, Foeniculum vulgare, Larrea tridentata, Musa acuminata and Olea europaea. Contrary to the above data, activity against drug-resistant variants of M. tuberculosis was more evident, e.g. N. officinale was the most potent (MIC < or = 100 microg/mL) against the four mono-resistant variants tested; F. vulgare and O. europaea were active against all the resistant variants (MICs < or = 100 microg/mL). The most susceptible variant was the isoniazid resistant, being inhibited by C. aurantifolia, C. sinensis and O. europaea (MIC = 25 microg/mL). These data point to the importance of biological testing of extracts against drug-resistant M. tuberculosis isolates, and the bioguided assay of these extracts for the identification of lead compounds against MDR-TB isolates.
Migliori, G. B.; Ambrosetti, M.; Besozzi, G.; Farris, B.; Nutini, S.; Saini, L.; Casali, L.; Nardini, S.; Bugiani, M.; Neri, M.; Raviglione, M. C.
Although in developing countries the treatment of tuberculosis (TB) cases is among the most cost-effective health interventions, few studies have evaluated the cost-effectiveness of TB control in low-prevalence countries. The aim of the present study was to carry out an economic analysis in Italy that takes into account both the perspective of the resource-allocating authority (i.e. the Ministry of Health) and the broader social perspective, including a cost description based on current outcomes applied to a representative sample of TB patients nationwide (admission and directly observed treatment (DOT) during the initial intensive phase of treatment); a cost-comparison analysis of two alternative programmes: current policy based on available data (scenario 1) and an hypothetical policy oriented more towards outpatient care (scenario 2) (both scenarios included the option of including or not including DOT outside hospital admission, and incentives) were compared in terms of cost per case treated successfully. Indirect costs (such as loss of productivity) were included in considerations of the broader social perspective. The study was designed as a prospective monitoring activity based on the supervised collection of forms from a representative sample of Italian TB units. Individual data were collected and analysed to obtain a complete economic profile of the patients enrolled and to evaluate the effectiveness of the intervention. A separate analysis was done for each scenario to determine the end-point at different levels of cure rate (50-90%). The mean length of treatment was 6.6 months (i.e. patients hospitalized during the intensive phase; length of stay was significantly higher in smear-positive patients and in human immunodeficiency virus (HIV) seropositive patients). Roughly six direct smear and culture examinations were performed during hospital admission and three during ambulatory treatment. The cost of a single bed day was US$186.90, whereas that of a
Wong, Dennis; Chao, Joseph D; Av-Gay, Yossef
Mycobacterium tuberculosis (Mtb) infects human alveolar macrophages and relies on the inhibition of phagosome acidification and maturation. This is, in part, dependent on the disruption of host signaling networks within the macrophage. In recent years, Mtb-secreted protein- and lipid-phosphatases protein-tyrosine phosphatase A (PtpA), PtpB, and secreted acid phosphatase M (SapM) have been shown to contribute to Mtb pathogenicity. Here, we review the current knowledge on PtpA, PtpB, and SapM focusing on their ability to interfere with host functions. We further explore how these phosphatase-dependent host-pathogen interactions can be targeted for novel tuberculosis (TB) drug discovery and examine the ongoing development of inhibitors against these phosphatases.
Background Tuberculosis is currently the second highest cause of death from infectious diseases worldwide. The emergence of multi and extensive drug resistance is threatening to make tuberculosis incurable. There is growing evidence that the genetic diversity of Mycobacterium tuberculosis may have important clinical consequences. Therefore, combining genetic, clinical and socio-demographic data is critical to understand the epidemiology of this infectious disease, and how virulence and other phenotypic traits evolve over time. This requires dedicated bioinformatics platforms, capable of integrating and enabling analyses of this heterogeneous data. Results We developed inTB, a web-based system for integrated warehousing and analysis of clinical, socio-demographic and molecular data for Mycobacterium sp. isolates. As a database it can organize and display data from any of the standard genotyping methods (SNP, MIRU-VNTR, RFLP and spoligotype), as well as an extensive array of clinical and socio-demographic variables that are used in multiple countries to characterize the disease. Through the inTB interface it is possible to insert and download data, browse the database and search specific parameters. New isolates are automatically classified into strains according to an internal reference, and data uploaded or typed in is checked for internal consistency. As an analysis framework, the system provides simple, point and click analysis tools that allow multiple types of data plotting, as well as simple ways to download data for external analysis. Individual trees for each genotyping method are available, as well as a super tree combining all of them. The integrative nature of inTB grants the user the ability to generate trees for filtered subsets of data crossing molecular and clinical/socio-demografic information. inTB is built on open source software, can be easily installed locally and easily adapted to other diseases. Its design allows for use by research
Jacobson, Karen B.; Moll, Anthony P.; Friedland, Gerald H.; Shenoi, Sheela V.
Background HIV and tuberculosis (TB) coinfection remains a major public health threat in sub-Saharan Africa. Integration and decentralization of HIV and TB treatment services are being implemented, but data on outcomes of this strategy are lacking in rural, resource-limited settings. We evaluated TB treatment outcomes in TB/HIV coinfected patients in an integrated and decentralized system in rural KwaZulu-Natal, South Africa. Methods We retrospectively studied a cohort of HIV/TB coinfected patients initiating treatment for drug-susceptible TB at a district hospital HIV clinic from January 2012-June 2013. Patients were eligible for down-referral to primary health clinics(PHCs) for TB treatment completion if they met specific clinical criteria. Records were reviewed for patients’ demographic, baseline clinical and laboratory information, past HIV and TB history, and TB treatment outcomes. Results Of 657(88.7%) patients, 322(49.0%) were female, 558(84.9%) were new TB cases, and 572(87.1%) had pulmonary TB. After TB treatment initiation, 280(42.6%) were down-referred from the district level HIV clinic to PHCs for treatment completion; 377(57.4%) remained at the district hospital. Retained patients possessed characteristics indicative of more severe disease. In total, 540(82.2%) patients experienced treatment success, 69(10.5%) died, and 46(7.0%) defaulted. Down-referred patients experienced higher treatment success, and lower mortality, but were more likely to default, primarily at the time of transfer to PHC. Conclusion Decentralization of TB treatment to the primary care level is feasible in rural South Africa. Treatment outcomes are favorable when patients are carefully chosen for down-referral. Higher mortality in retained patients reflects increased baseline disease severity while higher default among down-referred patients reflects failed linkage of care. Better linkage mechanisms are needed including improved identification of potential defaulters, increased
Background Interferon-gamma release assays have emerged as a more specific alternative to the tuberculin skin test (TST) for detection of tuberculosis (TB) infection, especially in Bacille Calmette-Guérin (BCG) vaccinated people. We determined the prevalence of Mycobacterium tuberculosis infection by TST and QuantiFERON®-TB Gold In-Tube (QFT-GIT) and assessed agreement between the two test methods and factors associated with positivity in either test in Warao Amerindian children in Venezuela. Furthermore, progression to active TB disease was evaluated for up to 12 months. Methods 163 HIV-negative childhood household contacts under 16 years of age were enrolled for TST, QFT-GIT and chest X-ray (CXR). Follow-up was performed at six and 12 months. Factors associated with TST and QFT-GIT positivity were studied using generalized estimation equations logistic regression models. Results At baseline, the proportion of TST positive children was similar to the proportion of children with a positive QFT-GIT (47% vs. 42%, p = 0.12). Overall concordance between QFT-GIT and TST was substantial (kappa 0.76, 95% CI 0.46-1.06). Previous BCG vaccination was not associated with significantly increased positivity in either test (OR 0.68, 95% CI 0.32-1.5 for TST and OR 0.51, 95% CI 0.14-1.9 for QFT-GIT). Eleven children were diagnosed with active TB at baseline. QFT-GIT had a higher sensitivity for active TB (88%, 95% CI 47-98%) than TST (55%, 95% CI 24-83%) while specificities were similar (respectively 58% and 55%). Five initially asymptomatic childhood contacts progressed to active TB disease during follow-up. Conclusion Replacement of TST by the QFT-GIT for detection of M. tuberculosis infection is not recommended in this resource-constrained setting as test results showed substantial concordance and TST positivity was not affected by previous BCG vaccination. The QFT-GIT had a higher sensitivity than the TST for the detection of TB disease. However, the value of the QFT
Baska, Ferenc; Székely, Edina Rita; Szántai-Kis, Csaba; Bánhegyi, Péter; Hegymegi-Barakonyi, Bálint; Németh, Gábor; Breza, Nóra; Zsákai, Lilian; Greff, Zoltán; Pató, János; Kéri, György; Orfi, Lászlo
Tuberculosis is considered to be one of the major health problem not only in the less developed countries but in the economically developed countries as well. Roughly one third of the world's population are infected with Mycobacterium tuberculosis and a significant part of them are carriers of latent tuberculosis. From ten percent of these latent infections are developing the active TB disease and fifty percent of them die from the illness without appropriate treatment. The drug-resistant Mycobacterium tuberculosis (MDR-TB, XDR-TB) and TB-HIV co-infection attracted attention to the most serious infectious disease. Inhibition of alternative signaling pathways were an important part of the research strategies for cancer and inflammatory diseases in recent years. In case of Mycobacterium tuberculosis such pathways were also identified, for example, three serine-threonine kinases (PknA, PknB, PknG) which are necessary and essential for bacterial growth. In this paper we summarize our best anti-TB active compounds, their biological effects and structure-activity relationships using in silico modeling, biochemical measurements and tests on active bacteria.
Ben-Selma, Walid; Harizi, Hedi; Boukadida, Jalel
For rapid diagnosis and discrimination between active tuberculosis (TB) and other pulmonary diseases, we evaluated the clinical usefulness of detection of serum immunoglobulin IgG and IgM antibodies raised against mycobacterial 38-kDa, 16-kDa, and 6-kDa antigens by a commercial rapid immunochromatographic IgG/IgM test (Standard Diagnostics, South Korea) in 246 serum samples from three groups of patients: (i) 171 patients with active TB (128 with pulmonary TB [pTB] and 43 with extrapulmonary TB [epTB]), (ii) 73 patients with pulmonary non-TB diseases, and (iii) two leprosy patients. The sensitivities of IgG and IgM in patients with active TB (pTB and epTB) were 68.4% and 2.3%, respectively. IgG had the best performance characteristics, with sensitivities of 78.1% and 39.5% in sera from patients with active pTB and epTB, respectively, and a specificity of 100%. The sensitivities of IgM were poor and were similar for pTB and epTB (2.3%). In contrast, specificity was very elevated (100%). The combination of IgG with IgM did not improve its sensitivity. IgG-mediated responses against the mycobacterial 38-kDa, 16-kDa, and 6-kDa antigens might constitute a clinically useful tool for presumptive diagnosis and discrimination of active pTB from other pulmonary diseases. Moreover, based on its simplicity and rapidity of application, it could be a screening tool for active pTB in poorly equipped laboratories.
Prasad, B M; Satyanarayana, S; Chadha, S S; Das, A; Thapa, B; Mohanty, S; Pandurangan, S; Babu, E R; Tonsing, J; Sachdeva, K S
In India, to increase tuberculosis (TB) case detection under the National Tuberculosis Programme, active case finding (ACF) was implemented by the Global Fund-supported Project Axshya, among high-risk groups in 300 districts. Between April 2013 and December 2014, 4.9 million households covering ~20 million people were visited. Of 350 047 presumptive pulmonary TB cases (cough of ⩾2 weeks) identified, 187 586 (54%) underwent sputum smear examination and 14 447 (8%) were found to be smear-positive. ACF resulted in the detection of a large number of persons with presumptive pulmonary TB and smear-positive TB. Ensuring sputum examination of all those with presumptive TB was a major challenge.
Pan, Sheng-Wei; Yen, Yung-Feng; Feng, Jia-Yih; Su, Vincent Yi-Fong; Kou, Yu Ru; Su, Wei-Juin
Tuberculosis (TB) disease may be transmitted to close contacts of index cases, causing physical illness. No studies have investigated the risk of developing depressive disorder among TB contacts in a TB-endemic area.Adult participants with a new diagnosis of TB contact (ICD-9-CM codes V01.1 plus chest radiographic order) since January 1, 2008, were identified from the National Health Insurance Research Database in Taiwan. A control cohort matched for age (±5 y), sex, enrolled years, and income level was selected. These 2 cohorts were followed until December 31, 2012, and observed for the development of depressive disorder. The Kaplan-Meier method and the log-rank test were used to examine the difference in cumulative incidences of depressive disorder between groups. Cox proportional-hazard models were used to calculate adjusted hazard ratios (aHRs) for depressive disorder.The TB contact cohort consisted of 9046 patients and matched controls of 36,184 ones. The mean age of TB contacts was 44.7 years, and 56.0% of them were women. During a mean follow-up period of 2.5 years, 127 (1.40%) TB contacts and 521 (1.44%) matched controls developed depressive disorder. TB exposure was found to be an independent risk factor of depressive disorder in women (aHR 1.34, 95% confidence interval [CI] 1.07-1.68), but not in men (aHR 0.71, 95% CI 0.48-1.06) after adjusting for age, comorbidities, and income levels. The risk of depression was significantly higher for female TB contacts than for matched controls in the first and second years (aHR 1.49, 95% CI 1.03-2.14; and aHR 1.53, 95% CI 1.05-2.23, respectively), but not thereafter. Of note, 67 (0.74%) TB contacts and 88 (0.24%) matched controls developed active TB, but none of them had subsequent depressive disorder during follow-up periods.Female TB contacts had an increased risk of depression within the first 2 years after exposure. Clinicians should consider conducting depression evaluations in addition to routine TB contact
Villaseñor, Tomás; Madrid-Paulino, Edgardo; Maldonado-Bravo, Rafael; Urbán-Aragón, Antonio; Pérez-Martínez, Leonor; Pedraza-Alva, Gustavo
Mycobacterium tuberculosis (M. tuberculosis), an intracellular pathogenic Gram-positive bacterium, is the cause of tuberculosis (TB), a major worldwide human infectious disease. The innate immune system is the first host defense against M. tuberculosis. The recognition of this pathogen is mediated by several classes of pattern recognition receptors expressed on the host innate immune cells, including Toll-like receptors, Nod-like receptors, and C-type lectin receptors like Dectin-1, the Mannose receptor, and DC-SIGN. M. tuberculosis interaction with any of these receptors activates multiple signaling pathways among which the protein kinase C, the MAPK, and the NFκB pathways have been widely studied. These pathways have been implicated in macrophage invasion, M. tuberculosis survival, and impaired immune response, thus promoting a successful infection and disease. Interestingly, the Wnt signaling pathway, classically regarded as a pathway involved in the control of cell proliferation, migration, and differentiation in embryonic development, has recently been involved in immunoregulatory mechanisms in infectious and inflammatory diseases, such as TB, sepsis, psoriasis, rheumatoid arthritis, and atherosclerosis. In this review, we present the current knowledge supporting a role for the Wnt signaling pathway during macrophage infection by M. tuberculosis and the regulation of the immune response against M. tuberculosis. Understanding the cross talk between different signaling pathways activated by M. tuberculosis will impact on the search for new therapeutic targets to fuel the rational design of drugs aimed to restore the immunological response against M. tuberculosis. PMID:28203237
Villaseñor, Tomás; Madrid-Paulino, Edgardo; Maldonado-Bravo, Rafael; Urbán-Aragón, Antonio; Pérez-Martínez, Leonor; Pedraza-Alva, Gustavo
Mycobacterium tuberculosis (M. tuberculosis), an intracellular pathogenic Gram-positive bacterium, is the cause of tuberculosis (TB), a major worldwide human infectious disease. The innate immune system is the first host defense against M. tuberculosis. The recognition of this pathogen is mediated by several classes of pattern recognition receptors expressed on the host innate immune cells, including Toll-like receptors, Nod-like receptors, and C-type lectin receptors like Dectin-1, the Mannose receptor, and DC-SIGN. M. tuberculosis interaction with any of these receptors activates multiple signaling pathways among which the protein kinase C, the MAPK, and the NFκB pathways have been widely studied. These pathways have been implicated in macrophage invasion, M. tuberculosis survival, and impaired immune response, thus promoting a successful infection and disease. Interestingly, the Wnt signaling pathway, classically regarded as a pathway involved in the control of cell proliferation, migration, and differentiation in embryonic development, has recently been involved in immunoregulatory mechanisms in infectious and inflammatory diseases, such as TB, sepsis, psoriasis, rheumatoid arthritis, and atherosclerosis. In this review, we present the current knowledge supporting a role for the Wnt signaling pathway during macrophage infection by M. tuberculosis and the regulation of the immune response against M. tuberculosis. Understanding the cross talk between different signaling pathways activated by M. tuberculosis will impact on the search for new therapeutic targets to fuel the rational design of drugs aimed to restore the immunological response against M. tuberculosis.
Tabarsi, Payam; Yousefzadeh, Amir; Najafizadeh, Katayoun; Droudinia, Atousa; Bayati, Rouzbeh; Marjani, Majid; Shafaghi, Shadi; Farokhzad, Banafsheh; Javanmard, Pedram; Velayati, Ali Akbar
With regard to the significant morbidity and mortality due to tuberculosis in lung transplant recipients, the identification of brain-dead organ donors with latent tuberculosis by use of the QuantiFERON TB Gold (QFT-G) test may be of help to reduce the risk of TB reactivation and mortality in lung recipients. This study was conducted in the National Research Institute of Tuber-culosis and Lung Diseases (NRITLD) in Iran, from January to March 2013. A total of 38 conse-cutive brain-dead donors, not currently infected with active tuberculosis, were recruited. The medi-cal records of all the study enrollees were reviewed. A whole-blood IFN- release assay (IGRA) in reaction to early secreted antigenic target 6 (ESAT-6), culture filtrate protein 10 (CFP-10), and TB7.7 antigens, was performed and the released Interferon- was measured via enzyme-linked immunosorbent assay (ELISA). The data was analyzed with QFT-G software which was provided by the company. The demographic, characteristics and other variables were entered into SPSS version 11.5. The QFT-G test results of three donors (7.9%) turned out to be positive, negative for 24 donors (63.1%), and indeterminate for 11 cases (28.9%). Our study revealed the potential advantages of QFT-G in lowering the incidence of donor-derived post-transplant tuberculosis among lung recipients. However, a high rate of indeterminate results restricted the performance of QFT-G in this study.
Al Jahdali, Hamdan; Ahmed, Anwar E; Balkhy, Hanan H; Baharoon, Salim; Al Hejaili, Fayez F; Hajeer, Ali; Memish, Ziad; Binsalih, Salih; Al Sayyari, Abdullah A
Dialysis patients are more likely than the general population to develop active tuberculosis (TB). In these patients, the availability of a highly sensitive and specific test to diagnose latent TB will ensure earlier treatment and decreased progression to active disease. In the current study, the Quanti-FERON-TB Gold In-Tube (QFT-G) test was compared with the tuberculin skin test (TST) for the diagnosis of latent tuberculosis infection (LTBI) among 200 hemodialysis patients and 15 confirmed TB disease cases in a tertiary care center in Saudi Arabia. Among the LTBI cases, 26 (13%) were TST positive, and 65 (32.5%) were positive by the QTF-G test, with an overall agreement between the 2 tests of 75.5% (k=0.34) being observed. Among the confirmed tuberculosis disease cases, none were positive by TST, and 10 (66.7%) were positive by the QTF-G test, resulting in an overall agreement of 33.3% (k=0). A comparison between the TST and the QTF-G test was performed based on the sensitivity, specificity, and area under the curve (AUC) obtained for the tests. The QTF-G test was more sensitive and less specific than the TST in predicting the confirmed TB disease cases. When we tested the correspondence of the AUC values between the 2 diagnostic modalities, the obtained p-value was 0.0003. In conclusion, the AUCs of the examined diagnostic modalities are significantly different in predicting LTBI and tuberculosis.
An der Heiden, Maria; Hauer, Barbara; Fiebig, Lena; Glaser-Paschke, Gisela; Stemmler, Markus; Simon, Claudia; Rüsch-Gerdes, Sabine; Gilsdorf, Andreas; Haas, Walter
In July 2013, a passenger died of infectious extensively drug-resistant tuberculosis (XDR-TB) on board of an aircraft after a 3-hour flight from Turkey to Germany. Initial information indicated the patient had moved about the aircraft coughing blood. We thus aimed to contact and inform all persons exposed within the aircraft and to test them for newly acquired TB infection. Two-stage testing within 8 weeks from exposure and at least 8 weeks after exposure was suggested, using either interferon gamma release assays (IGRAs) or tuberculin skin test (TST). The TST cut-off was defined at a diameter > 10 mm; for differentiation between conversion and boosting, conversion was defined as increase of skin induration > 5 mm. Overall, 155 passengers and seven crew members were included in the investigation: the questionnaire response rate was 83%; 112 (69%) persons were tested at least once for TB infection. In one passenger, who sat next to the area where the patient died, a test conversion was registered. As of March 2017, no secondary active TB cases have been reported. We describe an unusual situation in which we applied contact tracing beyond existing European guidelines; we found one latent tuberculosis infection in a passenger, which we consider probably newly acquired.
Pérez del Molino Bernal, Inmaculada C.; Lillebaek, Troels; Pedersen, Mathias K.; Martinez-Martinez, Luis; Folkvardsen, Dorte B.; Agüero, Jesús; Rasmussen, E. Michael
Background Tuberculosis (TB) control strategies are focused mainly on prevention, early diagnosis, compliance to treatment and contact tracing. The objectives of this study were to explore the frequency and risk factors of recent transmission of clinical isolates of Mycobacterium tuberculosis complex (MTBC) in Cantabria in Northern Spain from 2012 through 2013 and to analyze their clonal complexity for better understanding of the transmission dynamics in a moderate TB incidence setting. Methods DNA from 85 out of 87 isolates from bacteriologically confirmed cases of MTBC infection were extracted directly from frozen stocks and genotyped using the mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) method. The MIRU-VNTRplus database tool was used to identify clusters and lineages and to build a neighbor joining (NJ) phylogenetic tree. In addition, data were compared to the SITVIT2 database at the Pasteur Institute of Guadeloupe. Results The rate of recent transmission was calculated to 24%. Clustering was associated with being Spanish-born. A high prevalence of isolates of the Euro-American lineage was found. In addition, MIRU-VNTR profiles of the studied isolates corresponded to previously found MIRU-VNTR types in other countries, including Spain, Belgium, Great Britain, USA, Croatia, South Africa and The Netherlands. Six of the strains analyzed represented clonal variants. Conclusion Transmission of MTBC is well controlled in Cantabria. The majority of TB patients were born in Spain. The population structure of MTBC in Cantabria has a low diversity of major clonal lineages with the Euro-American lineage predominating. PMID:27315243
Henostroza, German; Topp, Stephanie M.; Hatwiinda, Sisa; Maggard, Katie R.; Phiri, Winifreda; Harris, Jennifer B.; Krüüner, Annika; Kapata, Nathan; Ayles, Helen; Chileshe, Chisela; Reid, Stewart E.
Background Tuberculosis (TB) and human immunodeficiency virus (HIV) represent two of the greatest health threats in African prisons. In 2010, collaboration between the Centre for Infectious Disease Research in Zambia, the Zambia Prisons Service, and the National TB Program established a TB and HIV screening program in six Zambian prisons. We report data on the prevalence of TB and HIV in one of the largest facilities: Lusaka Central Prison. Methods Between November 2010 and April 2011, we assessed the prevalence of TB and HIV amongst inmates entering, residing, and exiting the prison, as well as in the surrounding community. The screening protocol included complete history and physical exam, digital radiography, opt-out HIV counseling and testing, sputum smear and culture. A TB case was defined as either bacteriologically confirmed or clinically diagnosed. Results A total of 2323 participants completed screening. A majority (88%) were male, median age 31 years and body mass index 21.9. TB symptoms were found in 1430 (62%). TB was diagnosed in 176 (7.6%) individuals and 52 people were already on TB treatment at time of screening. TB was bacteriologically confirmed in 88 cases (3.8%) and clinically diagnosed in 88 cases (3.8%). Confirmed TB at entry and exit interventions were 4.6% and 5.3% respectively. Smear was positive in only 25% (n = 22) of bacteriologically confirmed cases. HIV prevalence among inmates currently residing in prison was 27.4%. Conclusion Ineffective TB and HIV screening programs deter successful disease control strategies in prison facilities and their surrounding communities. We found rates of TB and HIV in Lusaka Central Prison that are substantially higher than the Zambian average, with a trend towards concentration and potential transmission of both diseases within the facility and to the general population. Investment in institutional and criminal justice reform as well as prison-specific health systems is urgently required. PMID
Lalvani, Ajit; Pareek, Manish
Tuberculosis in the United Kingdom and other high-income countries is primarily a disease of the foreign-born arising from the synergy of migration from high TB burden regions and the reactivation of remotely acquired latent TB infection. UK immigrant screening policy primarily aims to identify active, rather than latent, TB although mounting evidence indicates that implementing latent TB screening for new entrants from intermediate and high incidence countries could cost-effectively reduce TB incidence in the UK.
Lilienkampf, Annamaria; Mao, Jialin; Wan, Baojie; Wang, Yuehong; Franzblau, Scott G; Kozikowski, Alan P
Tuberculosis (TB) remains as a global pandemic that is aggravated by a lack of health care, the spread of HIV, and the emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) strains. New anti-TB drugs are urgently required to shorten the long 6-12 month treatment regimen and to battle drug-resistant Mtb strains. We have identified several potent quinoline-based anti-TB compounds, bearing an isoxazole containing side-chain. The most potent compounds, 7g and 13, exhibited submicromolar activity against the replicating bacteria (R-TB), with minimum inhibitory concentrations (MICs) of 0.77 and 0.95 microM, respectively. In general, these compounds also had micromolar activity against the nonreplicating persistent bacteria (NRP-TB) and did not show toxicity on Vero cells up to 128 microM concentration. Compounds 7g and 13 were shown to retain their anti-TB activity against rifampin, isoniazid, and streptomycin resistant Mtb strains. The results suggest that quinoline-isoxazole-based anti-TB compounds are promising leads for new TB drug development.
O'Brien, Amanda; Whelan, Clare; Clarke, John B; Hayton, Alastair; Watt, Neil J; Harkiss, Gordon D
Tuberculosis in goats is usually diagnosed clinically, at postmortem, or by a positive skin test. However, none of these approaches detects all infected animals. Serology offers an additional tool to identify infected animals missed by current tests. We describe the use of the Enferplex Caprine TB serology test to aid the management of a large dairy goat herd undergoing a tuberculosis breakdown. Initial skin and serology testing showed that IgG antibodies were present in both serum and milk from 100% of skin test-positive animals and in serum and milk from 77.8 and 95.4% of skin test-negative animals, respectively. A good correlation was observed between serum and milk antibody levels. The herd had been vaccinated against Mycobacterium avium subsp. paratuberculosis, but no direct serological cross-reactions were found. Subsequent skin testing revealed 13.7% positive animals, 64.9% of which were antibody positive, while 42.1% of skin test-negative animals were seropositive. Antibody responses remained high 1 month later (57.1% positive), and the herd was slaughtered. Postmortem analysis of 20 skin test-negative goats revealed visible lesions in 6 animals, all of which had antibodies to six Mycobacterium bovis antigens. The results provide indirect evidence that serology testing with serum or milk could be a useful tool in the diagnosis and management of tuberculosis in goats.
Schnippel, Kathryn; Sharp, Alana
Objective Identifying those infected with tuberculosis (TB) is an important component of any strategy for reducing TB transmission and population prevalence. The Stop TB Global Partnership recently launched an initiative with a focus on key populations at greater risk for TB infection or poor clinical outcomes, due to housing and working conditions, incarceration, low household income, malnutrition, co-morbidities, exposure to tobacco and silica dust, or barriers to accessing medical care. To achieve operational targets, the global health community needs effective, low cost, and large-scale strategies for identifying key populations. Using South Africa as a test case, we assess the feasibility and effectiveness of targeting active case finding to populations with TB risk factors identified from regularly collected sources of data. Our approach is applicable to all countries with TB testing and census data. It allows countries to tailor their outreach activities to the particular risk factors of greatest significance in their national context. Methods We use a national database of TB test results to estimate municipality-level TB infection prevalence, and link it to Census data to measure population risk factors for TB including rates of urban households, informal settlements, household income, unemployment, and mobile phone ownership. To examine the relationship between TB prevalence and risk factors, we perform linear regression analysis and plot the set of population characteristics against TB prevalence and TB testing rate by municipality. We overlay lines of best fit and smoothed curves of best fit from locally weighted scatter plot smoothing. Findings Higher TB prevalence is statistically significantly associated with more urban municipalities (slope coefficient β1 = 0.129, p < 0.0001, R2 = 0.133), lower mobile phone access (β1 = -0.053, p < 0.001, R2 = 0.089), lower unemployment rates (β1 = -0.020, p = 0.003, R2 = 0.048), and a lower proportion of low
Heysell, Scott K; Mtabho, Charles; Mpagama, Stellah; Mwaigwisya, Solomon; Pholwat, Suporn; Ndusilo, Norah; Gratz, Jean; Aarnoutse, Rob E; Kibiki, Gibson S; Houpt, Eric R
Low antituberculosis (TB) drug levels are common, but their clinical significance remains unclear, and methods of measurement are resource intensive. Subjects initiating treatment for sputum smear-positive pulmonary TB were enrolled from Kibong'oto National TB Hospital, Tanzania, and levels of isoniazid, rifampin, ethambutol, and pyrazinamide were measured at the time of typical peak plasma concentration (C(2 h)). To evaluate the significance of the effect of observed drug levels on Mycobacterium tuberculosis growth, a plasma TB drug activity (TDA) assay was developed using the Bactec MGIT system. Time to detection of plasma-cocultured M. tuberculosis versus time to detection of control growth was defined as a TDA ratio. TDA assays were later performed using the subject's own M. tuberculosis isolate and C(2 h) plasma from the Tanzanian cohort and compared to drug levels and clinical outcomes. Sixteen subjects with a mean age of 37.8 years ± 10.7 were enrolled. Fourteen (88%) had C(2 h) rifampin levels and 11 (69%) had isoniazid levels below 90% of the lower limit of the expected range. Plasma spiked with various concentrations of antituberculosis medications found TDA assay results to be unaffected by ethambutol or pyrazinamide. Yet with a range of isoniazid and rifampin concentrations, TDA exhibited a statistically significant correlation with drug level and drug MIC, and a TDA of ~1.0 indicated the presence of multidrug-resistant TB. In Tanzania, low (≤ 2.0) TDA was significantly associated with both lower isoniazid and rifampin C(2 h) levels, and very low (≤ 1.5) TDA corresponded to a trend toward lack of cure. Study of TDA compared to additional clinical outcomes and as a therapeutic management tool is warranted.
Koseki, Yuji; Aoki, Shunsuke
Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis and is a common infectious disease with high mortality and morbidity. The increasing prevalence of drug-resistant strains of TB presents a major public health problem. Due to the lack of effective drugs to treat these drug-resistant strains, the discovery or development of novel anti-TB drugs is important. Computer-aided drug design has become an established strategy for the identification of novel active chemicals through a combination of several drug design tools. In this review, we summarise the current chemotherapy for TB, describe attractive target proteins for the development of antibiotics against TB, and detail several computational drug design strategies that may contribute to the further identification of active chemicals for the treatment of not only TB but also other diseases.
Achkar, Jacqueline M.; Cortes, Laetitia; Croteau, Pascal; Yanofsky, Corey; Mentinova, Marija; Rajotte, Isabelle; Schirm, Michael; Zhou, Yiyong; Junqueira-Kipnis, Ana Paula; Kasprowicz, Victoria O.; Larsen, Michelle; Allard, René; Hunter, Joanna; Paramithiotis, Eustache
Biomarkers for active tuberculosis (TB) are urgently needed to improve rapid TB diagnosis. The objective of this study was to identify serum protein expression changes associated with TB but not latent Mycobacterium tuberculosis infection (LTBI), uninfected states, or respiratory diseases other than TB (ORD). Serum samples from 209 HIV uninfected (HIV−) and co-infected (HIV+) individuals were studied. In the discovery phase samples were analyzed via liquid chromatography and mass spectrometry, and in the verification phase biologically independent samples were analyzed via a multiplex multiple reaction monitoring mass spectrometry (MRM-MS) assay. Compared to LTBI and ORD, host proteins were significantly differentially expressed in TB, and involved in the immune response, tissue repair, and lipid metabolism. Biomarker panels whose composition differed according to HIV status, and consisted of 8 host proteins in HIV− individuals (CD14, SEPP1, SELL, TNXB, LUM, PEPD, QSOX1, COMP, APOC1), or 10 host proteins in HIV+ individuals (CD14, SEPP1, PGLYRP2, PFN1, VASN, CPN2, TAGLN2, IGFBP6), respectively, distinguished TB from ORD with excellent accuracy (AUC = 0.96 for HIV− TB, 0.95 for HIV+ TB). These results warrant validation in larger studies but provide promise that host protein biomarkers could be the basis for a rapid, blood-based test for TB. PMID:26501113
Schepisi, Monica Sañé; Gualano, Gina; Piselli, Pierluca; Mazza, Marta; D’Angelo, Donatella; Fasciani, Francesca; Barbieri, Alberto; Rocca, Giorgia; Gnolfo, Filippo; Olivani, Piefranco; Ferrarese, Maurizio; Codecasa, Luigi Ruffo; Palmieri, Fabrizio; Girardi, Enrico
In Italy tuberculosis (TB) is largely concentrated in vulnerable groups such as migrants and in urban settings. We analyzed three TB case finding interventions conducted at primary centers and mobile clinics for regular/irregular immigrants and refugees/asylum seekers performed over a four-year period (November 2009-March 2014) at five different sites in Rome and one site in Milan, Italy. TB history and presence of symptoms suggestive of active TB were investigated by verbal screening through a structured questionnaire in migrants presenting for any medical condition to out-patient and mobile clinics. Individuals reporting TB history or symptoms were referred to a TB clinic for diagnostic workup. Among 6347 migrants enrolled, 891 (14.0%) reported TB history or symptoms suggestive of active TB and 546 (61.3%) were referred to the TB clinic. Of them, 254 (46.5%) did not present for diagnostic evaluation. TB was diagnosed in 11 individuals representing 0.17% of those screened and 3.76% of those evaluated. The overall yield of this intervention was in the range reported for other TB screening programs for migrants, although we recorded an unsatisfactory adherence to diagnostic workup. Possible advantages of this intervention include low cost and reduced burden of medical procedures for the screened population. PMID:27403270
Kabali, Conrad; Mtei, Lillian; Brooks, Daniel R; Waddell, Richard; Bakari, Muhammad; Matee, Mecky; Arbeit, Robert D; Pallangyo, Kisali; von Reyn, C Fordham; Horsburgh, C Robert
Active tuberculosis (TB) among HIV-infected patients, even when successfully treated, may be associated with excess mortality. We conducted a prospective cohort study nested in a randomized TB vaccine trial to compare mortality between HIV-infected patients diagnosed and treated for TB (TB, n = 77) and HIV-infected patients within the same CD4 range, who were not diagnosed with or treated for active TB (non-TB, n = 308) in the period 2001-2008. Only twenty four subjects (6%) were on antiretroviral therapy at the beginning of this study. After accounting for covariate effects including use of antiretroviral therapy, isoniazid preventive therapy, and receipt of vaccine, we found a four-fold increase in mortality in TB patients compared with non-TB patients (adjusted Hazard Ratio 4.61; 95% Confidence Interval (CI): 1.63, 13.05). These findings suggest that treatment for TB alone is not sufficient to avert the excess mortality associated with HIV-related TB and that prevention of TB may provide a mortality benefit.
Tănăsescu, Mihaela; Didilescu, Cristian; Marica, Constantin
Tuberculosis is still one of the diseases with a major medical and social impact, and in terms of early diagnosis (which would imply a fair treatment and established at the time), difficulties related to the delay bacilli isolation in culture, decreased susceptibility testing methods to antituberculosis drugs, lack of methods for differentiation of M. Tuberculosis complex germs of non TB Mycobacteria, may have important clinical implications. Traditional testing of anti-TB drug susceptibility on solid Löwenstein-Jensen medium (gold standard) or liquid media can only be performed using grown samples. Determining the time it takes up to 42 days on solid media and 12 days for liquid media. For MDR/XDR TB cases is absolutely essential to reduce the detection time. In these cases prove their usefulness rapid diagnostic methods. Automatic testing in liquid medium, molecular hybridization methods are currently recommended by the current WHO guidelines. Rapid diagnosis of MDR-TB is extremely useful for the early establishment of an effective treatment tailored more accurately on the spectrum of sensitivity of the resistant strain (thus reducing the risk of developing additional resistance to other drugs) and control the spread of these strains. Genetic diagnostic methods, approved and recommended by the WHO, can reduce the time of diagnosis of TB case and, importantly, the case of MDR TB. They do not replace the current standard diagnostic methods and resistance profile, but complete them in selected cases.
Wergeland, Ida; Assmus, Jörg; Dyrhol-Riise, Anne Ma
Background Interferon gamma release assays (IGRAs) do not discriminate between active tuberculosis (TB) and latent TB infection (LTBI), which limit their use in TB endemic areas. Subjects with QuantiFERON-TB (QFT) results around the diagnostic cut-off more likely show inconsistent results on serial testing which makes the interpretation of the assay difficult. We have studied potential biomarkers in patients with various stages of TB infection and with borderline QFT tests compared to those with higher values. Methods 27 soluble biomarkers were analysed in QFT supernatants from patients with active TB (n = 18), individuals with LTBI (n = 48) and from QFT negative controls (n = 16) by the Multiplex bead assay. The LTBI group was classified into two groups according to QFT IFN-γ levels; QFT borderline (0.35–0.70 IU/mL, n = 11) or QFT high (>0.70 IU/mL, n = 36). Results The levels of IL-1ra, IL-2, IL-13, IL-15, IFN-γ, IP-10 and MCP-1 in background corrected TB antigen stimulated supernatants (TBAg-Nil) significantly distinguished both active TB and LTBI QFT high groups from the QFT negative controls (p≤0.004). In addition, IL-1ra, IL-2 and IP-10 significantly differentiated the QFT borderline group from the controls (p≤0.001). Still, in the QFT borderline group the IL-1ra and IP-10 levels were not significant different from neither the QFT high nor the active TB group, whereas the IL-2 levels were lower (p≤0.003). The level of IP-10 showed the best separation between the QFT borderline group and the QFT negative controls (AUC 0.92) and offered 100% sensitivity for active TB. Conclusion IL-1ra, IL-2 and IP-10 differentiate QFT borderline samples from uninfected controls and the majority of QFT borderline subjects were classified as LTBI by these markers. Still, inconsistency was seen, and further studies are needed to examine the performance of alternative markers before concluded if they could be used as diagnostics tools. PMID:27685462
Iribarren, Sarah J; Rubinstein, Fernando; Discacciati, Vilda; Pearce, Patricia F
Purpose. In Argentina, tuberculosis (TB) control measures have not achieved key treatment targets. The purpose of this study was to identify modes of treatment delivery and explore patient and healthcare personnel perceptions of barriers and facilitators to treatment success. Methods. We used semistructured group and individual interviews for this descriptive qualitative study. Eight high burden municipalities were purposively selected. Patients in treatment for active TB (n = 16), multidisciplinary TB team members (n = 26), and TB program directors (n = 12) at local, municipal, regional, and national levels were interviewed. Interviews were recorded, transcribed verbatim, and analyzed using thematic analysis. Results. Modes of treatment delivery varied across municipalities and types of healthcare facility and were highly negotiated with patients. Self-administration of treatment was common in hospital-based and some community clinics. Barriers to TB treatment success were concentrated at the system level. This level relied heavily on individual personal commitment, and many system facilitators were operating in isolation or in limited settings. Conclusions. We outline experiences and perspectives of the facilitating and challenging factors at the individual, structural, social, and organizational levels. Establishing strong patient-healthcare personnel relationships, responding to patient needs, capitalizing on community resources, and maximizing established decentralized system could mitigate some of the barriers.
Iribarren, Sarah J.; Rubinstein, Fernando; Discacciati, Vilda; Pearce, Patricia F.
Purpose. In Argentina, tuberculosis (TB) control measures have not achieved key treatment targets. The purpose of this study was to identify modes of treatment delivery and explore patient and healthcare personnel perceptions of barriers and facilitators to treatment success. Methods. We used semistructured group and individual interviews for this descriptive qualitative study. Eight high burden municipalities were purposively selected. Patients in treatment for active TB (n = 16), multidisciplinary TB team members (n = 26), and TB program directors (n = 12) at local, municipal, regional, and national levels were interviewed. Interviews were recorded, transcribed verbatim, and analyzed using thematic analysis. Results. Modes of treatment delivery varied across municipalities and types of healthcare facility and were highly negotiated with patients. Self-administration of treatment was common in hospital-based and some community clinics. Barriers to TB treatment success were concentrated at the system level. This level relied heavily on individual personal commitment, and many system facilitators were operating in isolation or in limited settings. Conclusions. We outline experiences and perspectives of the facilitating and challenging factors at the individual, structural, social, and organizational levels. Establishing strong patient-healthcare personnel relationships, responding to patient needs, capitalizing on community resources, and maximizing established decentralized system could mitigate some of the barriers. PMID:25328701
Al Kubaisy, W; Al Dulayme, A; Hashim, D S
In a prospective cohort study in Iraq, schoolchildren with a positive tuberculin skin test during the nationwide survey in 2000 were followed up in 2002 to determine prevalence of latent tuberculosis (TB) infection and risk factors among household contacts. Of 205 children, 191 remained skin-test positive in 2002. Based on X-ray and clinical examination, 9 children (4.4%) were active TB cases. Among 834 household contacts, there were 144 new TB cases, giving a cumulative incidence of 17.3%. Risk factors for TB among household contacts were: age > or = 15 years; technical/professional job; smoking; low body mass index; diabetes mellitus; steroid therapy; and closeness of contact with the index cases. Based on past history of TB in index children and their contacts, 77.2% of new TB cases were attributable to household contacts.
Nikitina, Irina Yu.; Panteleev, Alexander V.; Karpina, Natalya L.; Bagdasarian, Tatef R.; Burmistrova, Irina A.; Andreevskaya, Sofia N.; Chernousova, Larisa N.; Vasilyeva, Irina A.
IFN-γ is a key cytokine in antituberculosis (TB) defense. However, how the levels of its secretion affect M. tuberculosis (Mtb) infection is not clear. We have analyzed associations between IFN-γ responses measured in QuantiFERON®-TB Gold In-tube (QFT) assay, TB disease severity, and Mtb infection activity. TB severity was evaluated based on the results of radiological, microbiological, and clinical examinations. Antigen-driven IFN-γ secretion did not correlate with TB severity. Mitogen-induced IFN-γ secretion correlated inversely with the form of pulmonary pathology and the area of affected pulmonary tissue; the levels of spontaneous IFN-γ secretion correlated with patients' age (r = 0.395, p = 0.001). Mtb infection activity was evaluated based on radiological data of lung tissue infiltration, destruction, dissemination or calcification, and condensation. The rate of positive QFT results and the levels of antigen-driven IFN-γ secretion increased in a row: patients with residual TB lesions < patients with low TB activity < patients with high TB activity. Thus, antigen-driven IFN-γ secretion and QFT results did not associate with TB severity but associated with the infection activity. The results suggest that quantitative parameters of IFN-γ secretion play a minor role in determining the course of TB disease but mirror the activity of the infectious process. PMID:28042583
Nikitina, Irina Yu; Panteleev, Alexander V; Sosunova, Ekaterina V; Karpina, Natalya L; Bagdasarian, Tatef R; Burmistrova, Irina A; Andreevskaya, Sofia N; Chernousova, Larisa N; Vasilyeva, Irina A; Lyadova, Irina V
IFN-γ is a key cytokine in antituberculosis (TB) defense. However, how the levels of its secretion affect M. tuberculosis (Mtb) infection is not clear. We have analyzed associations between IFN-γ responses measured in QuantiFERON®-TB Gold In-tube (QFT) assay, TB disease severity, and Mtb infection activity. TB severity was evaluated based on the results of radiological, microbiological, and clinical examinations. Antigen-driven IFN-γ secretion did not correlate with TB severity. Mitogen-induced IFN-γ secretion correlated inversely with the form of pulmonary pathology and the area of affected pulmonary tissue; the levels of spontaneous IFN-γ secretion correlated with patients' age (r = 0.395, p = 0.001). Mtb infection activity was evaluated based on radiological data of lung tissue infiltration, destruction, dissemination or calcification, and condensation. The rate of positive QFT results and the levels of antigen-driven IFN-γ secretion increased in a row: patients with residual TB lesions < patients with low TB activity < patients with high TB activity. Thus, antigen-driven IFN-γ secretion and QFT results did not associate with TB severity but associated with the infection activity. The results suggest that quantitative parameters of IFN-γ secretion play a minor role in determining the course of TB disease but mirror the activity of the infectious process.
Sutherland, Jayne S.; Lalor, Maeve K.; Black, Gillian F.; Ambrose, Lyn R.; Loxton, Andre G.; Chegou, Novel N.; Kassa, Desta; Mihret, Adane; Howe, Rawleigh; Mayanja-Kizza, Harriet; Gomez, Marie P.; Donkor, Simon; Franken, Kees; Hanekom, Willem; Klein, Michel R.; Parida, Shreemanta K.; Boom, W. Henry; Thiel, Bonnie A.; Crampin, Amelia C.; Ota, Martin; Walzl, Gerhard; Ottenhoff, Tom H. M.; Dockrell, Hazel M.; Kaufmann, Stefan H. E.
Background Tuberculosis (TB) remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb), which are relevant to protective immunity in high-endemic areas. Methods We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda). We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens) together with novel resuscitation-promoting factors (rpf), reactivation proteins, latency (Mtb DosR regulon-encoded) antigens, starvation-induced antigens and secreted antigens. Results There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST- and TST+ contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737) and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC), PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST+ contacts (LTBI) compared to TB and TST- contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen. Conclusions Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may
Maeda, Tomoyo; Banno, Shogo; Maeda, Shinji; Naniwa, Taio; Hayami, Yoshihito; Watanabe, Maiko; Itoh, Rei; Sato, Shigeki; Ueda, Ryuzo
We aimed to determine the sensitivity and specificity of QuantiFERON-TB Gold (QFT-G) in Japanese rheumatoid arthritis (RA) patients with a past history of tuberculosis (TB). We assessed whether it is possible to decrease the cutoff using receiver operating characteristic (ROC) analysis. We evaluated chest computed tomography (CT) findings, prior history of treatment, and contact with active TB in 370 RA patients. Forty-nine patients before initiation of treatment with tumor necrosis factor (TNF) inhibitors were divided into two groups: 22 with a past history of TB and 27 without. We estimated the efficacy of QFT-G compared with the tuberculin skin test and antituberculosis (anti-TB) glycolipid antigen antibody. QFT-G was positive (>or=0.35 IU/ml) in 13.6% with a past history of TB, increasing to 27.3% at the intermediate range cutoff of 0.1 IU/ml. The sensitivity and specificity of QFT-G was 0.27 and 1.00, respectively, at 0.1 IU/ml. Using ROC analysis, the area under the curve (AUC) of QFT-G but not for the other two tests was significantly large. QFT-G is a useful diagnostic method due to its superior specificity, but the use of a cutoff value of 0.35 IU/ml will likely result in an underestimate. We propose that a lower interferon-gamma (IFN-gamma) titer of 0.1 IU/ml be adopted when deciding to administer anti-TB drugs before initiation of TNF inhibitors.
Correa, Andre F.; Bastos, Izabela M. D.; Neves, David; Kipnis, Andre; Junqueira-Kipnis, Ana P.; de Santana, Jaime M.
Mycobacterium tuberculosis is one of the most prevalent human pathogens causing millions of deaths in the last years. Moreover, tuberculosis (TB) treatment has become increasingly challenging owing to the emergence of multidrug resistant M. tuberculosis strains. Thus, there is an immediate need for the development of new anti-TB drugs. Proteases appear to be a promising approach and may lead to shortened and effective treatments for drug-resistant TB. Although the M. tuberculosis genome predicts more than 100 genes encoding proteases, only a few of them have been studied. Aminopeptidases constitute a set of proteases that selectively remove amino acids from the N-terminus of proteins and peptides and may act as virulence factors, essential for survival and maintenance of many microbial pathogens. Here, we characterized a leucine aminopeptidase of M. tuberculosis (MtLAP) as a cytosolic oligomeric metallo-aminopeptidase. Molecular and enzymatic properties lead us to classify MtLAP as a typical member of the peptidase family M17. Furthermore, the aminopeptidase inhibitor bestatin strongly inhibited MtLAP activity, in vitro M. tuberculosis growth and macrophage infection. In murine model of TB, bestatin treatment reduced bacterial burden and lesion in the lungs of infected mice. Thus, our data suggest that MtLAP participates in important metabolic pathways of M. tuberculosis necessary for its survival and virulence and consequently may be a promising target for new anti-TB drugs.
Karadag, Omer; Aksu, Kenan; Sahin, Abdurrahman; Zihni, Figen Yargucu; Sener, Burcin; Inanc, Nevsun; Kalyoncu, Umut; Aydin, Sibel Zehra; Ascioglu, Sibel; Ocakci, Pinar Talu; Bilgen, Sule Apras; Keser, Gokhan; Inal, Vedat; Direskeneli, Haner; Calguneri, Meral; Ertenli, Ihsan; Kiraz, Sedat
A possible relationship between Takayasu arteritis (TA) and tuberculosis (TB) has been suggested. An increased frequency of tuberculin skin test (TST) was observed in TA patients. Quantiferon-TB Gold test (QFT) is a new in vitro assay measuring interferon-gamma response to M. tuberculosis antigens and helpful in diagnosing latent TB infection. The aim of this study was to investigate latent TB infection among TA patients by the use of both TST and QFT Gold test. Ninety-four (male/female: 7/87) TA patients fulfilling ACR 1990 TA criteria from three different university hospitals in Turkey and 107 control subjects without inflammatory diseases were included in the study. Data about medical history (TA and TB) were collected for both groups. TST and QFT were performed. TST values > or =5 mm for TA patients and > or =15 mm for controls was accepted as TST positivity. Even though TA group was older (40 +/- 12 vs. 32 +/- 8, P < 0.001), there was no significant difference between TA patients and controls regarding demographic characteristics. Six TA patients and one control had a history of previous TB infection (P = 0.054). Although TST positivity was higher in TA group [55 patients (62.5%) vs. 24 controls (41.4%), P = 0.008], QFT positivity was similar between two groups [21 patients (22.3%) vs. 24 controls (22.4%), P > 0.05]. QFT was negative in two of six TA patients with previous TB history. Rate of latent TB infection in TA patients measured with QFT is no more than controls. QFT seems to be a good and favorable test compared with TST in detecting LTBI in TA.
Brindha, Sridharan; Sundaramurthi, Jagadish Chandrabose; Velmurugan, Devadasan; Vincent, Savariar; Gnanadoss, John Joel
Repurposing has gained momentum globally and become an alternative avenue for drug discovery because of its better success rate, and reduced cost, time and issues related to safety than the conventional drug discovery process. Several drugs have already been successfully repurposed for other clinical conditions including drug resistant tuberculosis (DR-TB). Though TB can be cured completely with the use of currently available anti-tubercular drugs, emergence of drug resistant strains of Mycobacterium tuberculosis and the huge death toll globally, together necessitate urgently newer and effective drugs for TB. Therefore, we performed virtual screening of 1554 FDA approved drugs against murE, which is essential for peptidoglycan biosynthesis of M. tuberculosis. We used Glide and AutoDock Vina for virtual screening and applied rigid docking algorithm followed by induced fit docking algorithm in order to enhance the quality of the docking prediction and to prioritize drugs for repurposing. We found 17 drugs binding strongly with murE and three of them, namely, lymecycline, acarbose and desmopressin were consistently present within top 10 ranks by both Glide and AutoDock Vina in the induced fit docking algorithm, which strongly indicates that these three drugs are potential candidates for further studies towards repurposing for TB. PMID:28275291
Griffiths, Kristin L.; Ahmed, Mushtaq; Das, Shibali; Gopal, Radha; Horne, William; Connell, Terry D.; Moynihan, Kelly D.; Kolls, Jay K.; Irvine, Darrell J.; Artyomov, Maxim N.; Rangel-Moreno, Javier; Khader, Shabaana A.
The development of a tuberculosis (TB) vaccine that induces sterilizing immunity to Mycobacterium tuberculosis infection has been elusive. Absence of sterilizing immunity induced by TB vaccines may be due to delayed activation of mucosal dendritic cells (DCs), and subsequent delay in antigen presentation and activation of vaccine-induced CD4+ T-cell responses. Here we show that pulmonary delivery of activated M. tuberculosis antigen-primed DCs into vaccinated mice, at the time of M. tuberculosis exposure, can overcome the delay in accumulation of vaccine-induced CD4+ T-cell responses. In addition, activating endogenous host CD103+ DCs and the CD40–CD40L pathway can similarly induce rapid accumulation of vaccine-induced lung CD4+ T-cell responses and limit early M. tuberculosis growth. Thus, our study provides proof of concept that targeting mucosal DCs can accelerate vaccine-induced T-cell responses on M. tuberculosis infection, and provide insights to overcome bottlenecks in TB vaccine efficacy. PMID:28004802
den Hertog, Alice L; Menting, Sandra; Pfeltz, Richard; Warns, Matthew; Siddiqi, Salman H; Anthony, Richard M
For the past decades, an acidic pH has been used to render Mycobacterium tuberculosis susceptible to pyrazinamide for in vitro testing. Here, we show that at the standard breakpoint concentration and reduced culture temperatures, pyrazinamide (PZA) is active against tuberculosis (TB) at neutral pH. This finding should help unravel the mechanism of action of PZA and allow drug susceptibility testing (DST) methods to be optimized.
Rodrigues, Ivaneide Leal Ataide; Monteiro, Larissa Lima; Pacheco, Régia Hevelline Barros; da Silva, Sílvio Eder Dias
This study aimed at analyzing the reasons that patients co-infected with tuberculosis and HIV leave the treatment of tuberculosis and to know the conduct of the health team toward that abandonment. The study, using a qualitative approach, performed semi-structured interviews on 45 professionals working at a referral health center in Pará state. Two units emerged based on the thematic analysis: patient-associated factors that make TB treatment adherence difficult; and service-associated factors that contribute to treatment abandonment. It was found that, in terms of the patients, that their low socioeconomic condition was the most common factor that led to abandonment. Other factors that led to this outcome included the adverse drug effects, the use of illegal drugs, and poor personal motivation. Regarding the service, issues related to the physical structure, working process organization and accessibility were also relevant to their non-adherence. Results show there is a need to change the practices performed at the health care services.
Ottenhoff, Tom H. M.; Zhang, Mingzi M.; Wong, Hazel E. E.; Sahiratmadja, Edhyana; Khor, Chiea Chuen; Alisjahbana, Bachti; van Crevel, Reinout; Marzuki, Sangkot; Seielstad, Mark; van de Vosse, Esther; Hibberd, Martin L.
Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb), remains the leading cause of mortality from a single infectious agent. Each year around 9 million individuals newly develop active TB disease, and over 2 billion individuals are latently infected with M.tb worldwide, thus being at risk of developing TB reactivation disease later in life. The underlying mechanisms and pathways of protection against TB in humans, as well as the dynamics of the host response to M.tb infection, are incompletely understood. We carried out whole-genome expression profiling on a cohort of TB patients longitudinally sampled along 3 time-points: during active infection, during treatment, and after completion of curative treatment. We identified molecular signatures involving the upregulation of type-1 interferon (α/β) mediated signaling and chronic inflammation during active TB disease in an Indonesian population, in line with results from two recent studies in ethnically and epidemiologically different populations in Europe and South Africa. Expression profiles were captured in neutrophil-depleted blood samples, indicating a major contribution of lymphocytes and myeloid cells. Expression of type-1 interferon (α/β) genes mediated was also upregulated in the lungs of M.tb infected mice and in infected human macrophages. In patients, the regulated gene expression-signature normalized during treatment, including the type-1 interferon mediated signaling and a concurrent opposite regulation of interferon-gamma. Further analysis revealed IL15RA, UBE2L6 and GBP4 as molecules involved in the type-I interferon response in all three experimental models. Our data is highly suggestive that the innate immune type-I interferon signaling cascade could be used as a quantitative tool for monitoring active TB disease, and provide evidence that components of the patient’s blood gene expression signature bear similarities to the pulmonary and macrophage response to mycobacterial infection
Pollock, Katrina M; Montamat-Sicotte, Damien J; Grass, Lisa; Cooke, Graham S; Kapembwa, Moses S; Kon, Onn M; Sampson, Robert D; Taylor, Graham P; Lalvani, Ajit
HIV co-infection is an important risk factor for tuberculosis (TB) providing a powerful model in which to dissect out defective, protective and dysfunctional Mycobacterium tuberculosis (MTB)-specific immune responses. To identify the changes induced by HIV co-infection we compared MTB-specific CD4+ responses in subjects with active TB and latent TB infection (LTBI), with and without HIV co-infection. CD4+ T-cell subsets producing interferon-gamma (IFN-γ), interleukin-2 (IL-2) and tumour necrosis factor-alpha (TNF-α) and expressing CD279 (PD-1) were measured using polychromatic flow-cytometry. HIV-TB co-infection was consistently and independently associated with a reduced frequency of CD4+ IFN-γ and IL-2-dual secreting T-cells and the proportion correlated inversely with HIV viral load (VL). The impact of HIV co-infection on this key MTB-specific T-cell subset identifies them as a potential correlate of mycobacterial immune containment. The percentage of MTB-specific IFN-γ-secreting T-cell subsets that expressed PD-1 was increased in active TB with HIV co-infection and correlated with VL. This identifies a novel correlate of dysregulated immunity to MTB, which may in part explain the paucity of inflammatory response in the face of mycobacterial dissemination that characterizes active TB with HIV co-infection.
Canaday, David H; Sridaran, Sankar; Van Epps, Puja; Aung, Htin; Burant, Christopher J; Nsereko, Mary; Mayanja-Kizza, Harriet; Betts, Michael R; Toossi, Zahra
CD4+ T cell counts of HIV-infected individuals with pulmonary TB (PTB) are higher than with other opportunistic infections suggesting that progression to PTB is not merely due to T cell depletion but also dysfunction. There are limited data examining T cell functional signatures in human HIV-TB co-infection particularly in PTB which accounts for about 80% of active TB disease overall. We examined a cohort of HIV-infected anti-retroviral naïve individuals in Kampala, Uganda, a TB endemic area using multiparametric flow cytometry analysis to determine IFN-γ, IL-2, IL-17, and TNF-α production in CD4+ memory T cell subsets. The cytokine frequency and polyfunctionality profile of Mycobacterium tuberculosis (MTB)-specific CD4+ T cells in HIV-infected persons with latent TB infection (LTBI) or PTB is comparable. This similarity suggests that LTBI may represent a smoldering state of persistent MTB replication rather than dormant infection. This may be a contributory mechanism to the significantly increased risk of progression to PTB in this population.
Evaluation of the outcome of treatment by the cohort analysis method is an important aspect of TB control. In the Japanese tuberculosis (TB) surveillance system, the outcome of treatment is automatically classified by computer according to the order of pre-set algorithm, so the treatment outcome is evaluated very rigidly. Although treatment outcomes are classified roughly into the eight categories of "cured", "completed", "died", "failed", "defaulted", "transferred", "still on treatment" and "not evaluated", there are actually 15 categories in our surveillance system; each category of "completed", "defaulted", and "still on treatment" has two subcategories and "not evaluated" has five subcategories. In the case of new sputum smear positive pulmonary cases (n=9,421) newly notified in 2007, their treatment outcome was as follows; "success" which combined "cured" and "completed" was 45.5%, "died" was 18.4%, "failed" was 1.0%, "defaulted" was 5.0%, "transferred" was 3.2%, "still on treatment" was 12.0% and "not evaluated" was 14.9%. Among the 5.0% who were classified as "defaulted", 0.7% was due to treatment interruption for more than consecutive 60 days or 2 months, and 4.3% was due to premature treatment cessation of any causes. The category "not evaluated" includes those who died before beginning treatment, those whose initial treatment regimen is unknown, those whose treatment is other than standard treatment, those who stopped INH and/or RFP before treatment completion, and those whose information is insufficient for classifying treatment outcome. In addition to evaluation of treatment outcome by the cohort method, the proportion of deaths was observed among all forms of TB patients (n = 25,184) and new sputum smear positive pulmonary patients (n=9421) who were newly registered in 2007. 16.4% of all forms of TB cases and 22.5% of new sputum smear positive pulmonary cases died within one year after beginning of treatment. Among new sputum smear positive pulmonary
Rangel, Carlos Mario; Atencia, Cesar; Merayo-Lloves, Jesus; Fernandez-Vega Sanz, Alvaro
A 59-year-old Hispanic woman presented with a 3-year history of floaters associated with bilateral reduced visual acuity. Her best-corrected visual acuity (BCVA) was 20/40. Both anterior segments were without inflammation, but fundoscopy showed mild vitreous inflammation and multiple inflammatory choroidal lesions. Tests for inflammatory and infectious diseases were negative except for human leucocyte antigen A29. The patient was diagnosed with birdshot choroidoretinopathy, and treatment was initiated with cyclosporine A 2.5 mg/kg/day. One year after treatment, the patient reported systemic symptoms with no improvement in visual acuity. Fundus findings remained with vitreal inflammation. QuantiFERON-TB Gold In-Tube Test was positive, and a diagnosis of presumed latent ocular tuberculosis (TB) was made. We initiated anti-TB treatment for 9 months. At 6 months of anti-TB therapy, there was no active inflammation. The patient was followed for 2 years with no medications and no active inflammation. Her final BCVA was 20/25.
Mengiste, Bezatu; Mesfin, Frehiwot; Godana, Wanzahun
Objectives The aim of this study was to determine factors associated with active pulmonary tuberculosis seen in cases in Ambo Hospital, Ethiopia. Design A facility-based prospective case-control study. Setting Patients attending Ambo Hospital from 01 December 2011 to 29 March 2012. Participants The sample included 312 adult patients attending Ambo Hospital. The main outcome measure was presence of active pulmonary tuberculosis (TB). Explanatory measures Age, gender, occupation, educational status, marital status, place of residence, patient history of TB, family history of TB, human immunodeficiency virus (HIV) infection, smoking, alcohol intake, khat chewing, body mass index (BMI), employment, diabetes, history of asthma, previous history of worm infestation, history of hospitalisation, number of adults living in the household (HH), person per room, housing condition. Results A total of 312 study participants, including 104 active pulmonary tuberculosis (PTB) cases (cases) and 208 non-active PTB cases (controls), were recruited for the present study. Having one or more family member with a history of TB (OR = 4.4; 95% CI: 1.50–12.90), marital status (OR = 7.6; 95% CI: 2.2–12.6), male gender (OR = 3.2; 95% CI: 1.4–7), rural residence (OR = 3.3; P = 0.012), being a current or past smoker (OR = 2.8; 95% CI: 1.1–7.2), BMI < 18.5 (OR = 2.1; 95% CI: 1.03–4.2), HIV infection (OR = 8.8; 95% CI: 2.4–23.8) and a history of worm infestation (OR = 6.4; 95% CI: 2.6–15.4) remained significant independent host-related factors for active PTB. Conclusion Patients who came from a compound with more than two HHs were more likely to develop active PTB than those who came from a compound with only one HH. Those who lived in houses with no windows were more likely to develop active PTB than those who lived in houses with one or more windows, had a family history of TB, lived in rural areas. Sex of the patient was a predicting factor. Not being the owner of the house was
Fu, Yurong; Yi, Zhengjun; Li, Jianhua; Li, Ruifang
The mechanisms of latent tuberculosis (TB) infection remain elusive. Roles of microRNA (miRNA) have been highlighted in pathogen-host interactions recently. To identify miRNAs involved in the immune response to TB, expression profiles of miRNAs in CD4(+) T cells from patients with latent TB, active TB and healthy controls were investigated by microarray assay and validated by RT-qPCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used to analyse the significant functions and involvement in signalling pathways of the differentially expressed miRNAs. To identify potential target genes for miR-29, interferon-γ (IFN-γ) mRNA expression was measured by RT-qPCR. Our results showed that 27 miRNAs were deregulated among the three groups. RT-qPCR results were generally consistent with the microarray data. We observed an inverse correlation between miR-29 level and IFN-γ mRNA expression in CD4(+) T cells. GO and KEGG pathway analysis showed that the possible target genes of deregulated miRNAs were significantly enriched in mitogen-activated protein kinase signalling pathway, focal adhesion and extracellular matrix receptor interaction, which might be involved in the transition from latent to active TB. In all, for the first time, our study revealed that some miRNAs in CD4(+) T cells were altered in latent and active TB. Function and pathway analysis highlighted the possible involvement of miRNA-deregulated mRNAs in TB. The study might help to improve understanding of the relationship between miRNAs in CD4(+) T cells and TB, and laid an important foundation for further identification of the underlying mechanisms of latent TB infection and its reactivation.
Khan, Koushambhi Basu
There have been few ethnographic studies on gender aspects of tuberculosis (TB). In this article, drawing on a qualitative study on TB in Delhi slums and through an intersectional analysis of group interviews and personal narratives of women living with TB, I bring forth the "genderization" of TB and the associated sufferings for women. With my findings I demonstrate how gender, in conjunction with other social forces, influences the disease outcomes and stigmatizes women, how lives in slums are uniquely organized by multiple discourses that contribute to the gender makings of TB, and, finally, how women strategize to reduce their burden of illness.
Langendam, Miranda W.; Tiemersma, Edine W.; van der Werf, Marieke J.; Sandgren, Andreas
A recent systematic review concluded that there is insufficient evidence on the effectiveness to support or reject preventive therapy for treatment of contacts of patients with multidrug resistant tuberculosis (MDR-TB). Whether preventive therapy is favorable depends both on the effectiveness and the adverse events of the drugs used. We performed a systematic review to assess adverse events in healthy individuals and MDR-TB contacts treated with anti-tuberculosis drugs potentially effective for preventing development of MDR-TB. We searched MEDLINE, EMBASE, and other databases (August 2011). Record selection, data extraction, and study quality assessment were done in duplicate. The quality of evidence was assessed using the GRADE approach. Of 6,901 identified references, 20 studies were eligible. Among the 16 studies in healthy volunteers (a total of 87 persons on either levofloxacin, moxifloxacin, ofloxacin, or rifabutin, mostly for 1 week), serious adverse events and treatment discontinuation due to adverse events were rare (<1 and <5%, respectively), but mild adverse events frequently occurred. Due to small sample sizes of the levofloxacin and ofloxacin studies an increased frequency of mild adverse events compared to placebo could not be demonstrated or excluded. For moxifloxacin the comparative results were inconsistent. In four studies describing preventive therapy of MDR-TB contacts, therapy was stopped for 58–100% of the included persons because of the occurrence of adverse events ranging from mild adverse events such as nausea and dizziness to serious events requiring treatment. The quality of the evidence was very low. Although the number of publications and quality of evidence are low, the available evidence suggests that shortly after starting treatment the occurrence of serious adverse events is rare. Mild adverse events occur more frequently and may be of importance because these may provoke treatment interruption. PMID:23326464
Langendam, Miranda W; Tiemersma, Edine W; van der Werf, Marieke J; Sandgren, Andreas
A recent systematic review concluded that there is insufficient evidence on the effectiveness to support or reject preventive therapy for treatment of contacts of patients with multidrug resistant tuberculosis (MDR-TB). Whether preventive therapy is favorable depends both on the effectiveness and the adverse events of the drugs used. We performed a systematic review to assess adverse events in healthy individuals and MDR-TB contacts treated with anti-tuberculosis drugs potentially effective for preventing development of MDR-TB. We searched MEDLINE, EMBASE, and other databases (August 2011). Record selection, data extraction, and study quality assessment were done in duplicate. The quality of evidence was assessed using the GRADE approach. Of 6,901 identified references, 20 studies were eligible. Among the 16 studies in healthy volunteers (a total of 87 persons on either levofloxacin, moxifloxacin, ofloxacin, or rifabutin, mostly for 1 week), serious adverse events and treatment discontinuation due to adverse events were rare (<1 and <5%, respectively), but mild adverse events frequently occurred. Due to small sample sizes of the levofloxacin and ofloxacin studies an increased frequency of mild adverse events compared to placebo could not be demonstrated or excluded. For moxifloxacin the comparative results were inconsistent. In four studies describing preventive therapy of MDR-TB contacts, therapy was stopped for 58-100% of the included persons because of the occurrence of adverse events ranging from mild adverse events such as nausea and dizziness to serious events requiring treatment. The quality of the evidence was very low. Although the number of publications and quality of evidence are low, the available evidence suggests that shortly after starting treatment the occurrence of serious adverse events is rare. Mild adverse events occur more frequently and may be of importance because these may provoke treatment interruption.
Winetsky, Daniel E.; Almukhamedov, Olga; Pulatov, Dilshod; Vezhnina, Natalia; Dooronbekova, Aizhan; Zhussupov, Baurzhan
Setting Tuberculosis (TB) is highly prevalent in prisons of the former Soviet Union. Objective To understand the behavioral, demographic and biological factors placing inmates in Tajikistan at risk for active TB. Design We administered a behavioral and demographic survey to 1317 inmates in two prison facilities in Sughd province, Tajikistan along with radiographic screening for pulmonary TB. Suspected cases were confirmed bacteriologically. Inmates undergoing TB treatment were also surveyed. In-depth interviews were conducted with former prisoners to elicit relevant social and behavioral characteristics. Results We identified 59 cases of active pulmonary TB (prevalence 4.5%). Factors independently associated with increased prevalence of active TB were: HIV-infection by self-report (PR 7.88; 95%CI 3.40–18.28), history of previous TB (PR 10.21; 95%CI 6.27–16.63) and infrequent supplemental nutrition beyond scheduled meals (PR 3.00; 95%CI 1.67–5.62). Access to supplemental nutrition was associated with frequency of visits from friends and family and ability to rely on other inmates for help. Conclusion In prison facilities of Tajikistan, HIV-infection, injection drug use and low access to supplemental nutrition were associated with prevalent cases of active pulmonary TB. Policies that reduce HIV transmission among injection drug users and improve the nutritional status of socially isolated inmates may alleviate the TB burden in Tajikistan’s prisons. PMID:24465861
Gao, Wei; Kim, Jin-Yong; Anderson, Jeffrey R.; Akopian, Tatos; Hong, Seungpyo; Jin, Ying-Yu; Kandror, Olga; Kim, Jong-Woo; Lee, In-Ae; Lee, Sun-Young; McAlpine, James B.; Mulugeta, Surafel; Sunoqrot, Suhair; Wang, Yuehong; Yang, Seung-Hwan; Yoon, Tae-Mi; Goldberg, Alfred L.; Pauli, Guido F.; Cho, Sanghyun
Drug-resistant tuberculosis (TB) has lent urgency to finding new drug leads with novel modes of action. A high-throughput screening campaign of >65,000 actinomycete extracts for inhibition of Mycobacterium tuberculosis viability identified ecumicin, a macrocyclic tridecapeptide that exerts potent, selective bactericidal activity against M. tuberculosis in vitro, including nonreplicating cells. Ecumicin retains activity against isolated multiple-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of M. tuberculosis. The subcutaneous administration to mice of ecumicin in a micellar formulation at 20 mg/kg body weight resulted in plasma and lung exposures exceeding the MIC. Complete inhibition of M. tuberculosis growth in the lungs of mice was achieved following 12 doses at 20 or 32 mg/kg. Genome mining of lab-generated, spontaneous ecumicin-resistant M. tuberculosis strains identified the ClpC1 ATPase complex as the putative target, and this was confirmed by a drug affinity response test. ClpC1 functions in protein breakdown with the ClpP1P2 protease complex. Ecumicin markedly enhanced the ATPase activity of wild-type (WT) ClpC1 but prevented activation of proteolysis by ClpC1. Less stimulation was observed with ClpC1 from ecumicin-resistant mutants. Thus, ClpC1 is a valid drug target against M. tuberculosis, and ecumicin may serve as a lead compound for anti-TB drug development. PMID:25421483
El Daker, Sary; Sacchi, Alessandra; Tempestilli, Massimo; Carducci, Claudia; Goletti, Delia; Vanini, Valentina; Colizzi, Vittorio; Lauria, Francesco Nicola; Martini, Federico; Martino, Angelo
Tuberculosis (TB) is still the principal cause of death caused by a single infectious agent, and the balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. The aim of this work was to study the role of myeloid-derived suppressor cells (MDSCs) during active pulmonary tuberculosis at the site of infection. We observed an expansion of MDSCs in the lung and blood of patients with active TB, which are correlated with an enhanced amount of nitric oxide in the plasma. We also found that these cells have the remarkable ability to suppress T-cell response, suggesting an important role in the modulation of the immune response against TB. Interestingly, a trend in the diminution of MDSCs was found after an efficacious anti-TB therapy, suggesting that these cells may be used as a potential biomarker for monitoring anti-TB therapy efficacy. PMID:25879532
de Jong, Bouke C.; Hill, Philip C.; Aiken, Alex; Awine, Timothy; Antonio, Martin; Adetifa, Ifedayo M.; Jackson-Sillah, Dolly J.; Fox, Annette; DeRiemer, Kathryn; Gagneux, Sebastien; Borgdorff, Martien W.; McAdam, Keith P.W.J.; Corrah, Tumani; Small, Peter M.; Adegbola, Richard A.
Considerable variability exists in the outcome of M. tuberculosis infection. We hypothesized that M. africanum was less likely than M. tuberculosis to transmit and progress to tuberculosis disease. In a cohort study of tuberculosis patients and their household contacts in the Gambia, we categorized 1,808 HIV negative tuberculosis contacts according to exposure to M. tuberculosis or to M. africanum. A positive skin test indicated transmission and development of tuberculosis during 2 years of follow-up indicated progression to disease. Transmission was similar, but progression to disease was significantly lower in contacts exposed to M. africanum than to M. tuberculosis (1.0% vs 2.9%; Hazard Ratio (HR) 3.1, 95% CI 1.1–8.7). Within M. tuberculosis sensu stricto, contacts exposed to a Beijing family strain were most likely to progress to disease (5.6%; HR 6.7 (2.0–22) relative to M. africanum). M. africanum and M. tuberculosis transmit equally well to household contacts, but contacts exposed to M. africanum are less likely to progress to tuberculosis disease than those exposed to M. tuberculosis. The variable rate of progression by lineage suggests that TB variability matters in clinical settings and should be taken into account in studies evaluating tuberculosis vaccines and treatment regimens for latent tuberculosis infection. PMID:18702608
Sah, S K; Sahu, S K; Lamichhane, B; Bhatta, G K; Bhandari, K B; Owiti, P; Majumdar, S S
Setting: The three government tertiary care hospitals providing care for people living with the human immunodeficiency virus (PLHIV) in Kathmandu, Nepal. Objectives: To assess 1) the screening cascades for intensified case finding for tuberculosis (TB), 2) isoniazid preventive therapy (IPT), including demographic and clinical factors associated with treatment interruption, and 3) TB infection control (IC) in the health facilities. Design: A cross-sectional study of new PLHIV enrolled from January 2012 to December 2014. Results: Among 572 registered PLHIV, 91% were on antiretroviral therapy. Of those registered, 561 (98%) were screened for TB and 73 (13%) were diagnosed with TB (17 [25%] sputum smear-positive, 17 [25%] smear-negative and 35 [51%] extra-pulmonary). Among the 488 (87%) PLHIV without active TB, 157 (32%) were initiated on IPT, of whom 136 (87%) completed treatment and 17 (11%) interrupted treatment. Those who experienced adverse events were 12 times more likely to interrupt IPT. TB IC showed gaps in personal control measures and supporting structures and policies. Conclusion: The implementation of the Three I's for collaborative TB-HIV activities in pilot sites in Nepal was successful and should be scaled up.
Banu, Sayera; Rahman, Md. Toufiq; Uddin, Mohammad Khaja Mafij; Khatun, Razia; Khan, Md. Siddiqur Rahman; Rahman, Md. Mojibur; Uddin, Syed Iftekhar; Ahmed, Tahmeed; Heffelfinger, James D.
Background Understanding tuberculosis (TB) transmission dynamics is essential for establishing effective TB control strategies in settings where the burden and risk of transmission are high. The objectives of this study were to evaluate the effect of active screening on controlling TB transmission and also to characterize Mycobacterium tuberculosis strains for investigating transmission dynamics in a correctional setting. Methods The study was carried out in Dhaka Central Jail (DCJ), from October 2005 to February 2010. An active case finding strategy for pulmonary TB was established both at the entry point to the prison and inside the prison. Three sputum specimens were collected from all pulmonary TB suspects and subjected to smear microscopy, culture, and drug susceptibility testing as well as genotyping which included deletion analysis, spoligotyping and analysis of mycobacterial interspersed repetitive units (MIRU). Results A total of 60,585 inmates were screened during the study period. We found 466 inmates with pulmonary TB of whom 357 (77%) had positive smear microscopy results and 109 (23%) had negative smear microscopy results but had positive results on culture. The number of pulmonary TB cases declined significantly, from 49 cases during the first quarter to 8 cases in the final quarter of the study period (p=0.001). Deletion analysis identified all isolates as M. tuberculosis and further identified 229 (70%) strains as ‘modern’ and 100 (30%) strains as ‘ancestral’. Analysis of MIRU showed that 347 strains (85%) exhibited unique patterns, whereas 61 strains (15%) clustered into 22 groups. The largest cluster comprised eight strains of the Beijing M. tuberculosis type. The rate of recent transmission was estimated to be 9.6%. Conclusions Implementation of active screening for TB was associated with a decline in TB cases in DCJ. Implementation of active screening in prison settings might substantially reduce the national burden of TB in Bangladesh
Maduskar, Pragnya; Hogeweg, Laurens; Philipsen, Rick; Schalekamp, Steven; van Ginneken, Bram
Computer aided detection (CAD) of tuberculosis (TB) on chest radiographs (CXR) is challenging due to over-lapping structures. Suppression of normal structures can reduce overprojection effects and can enhance the appearance of diffuse parenchymal abnormalities. In this work, we compare two CAD systems to detect textural abnormalities in chest radiographs of TB suspects. One CAD system was trained and tested on the original CXR and the other CAD system was trained and tested on bone suppression images (BSI). BSI were created using a commercially available software (ClearRead 2.4, Riverain Medical). The CAD system is trained with 431 normal and 434 abnormal images with manually outlined abnormal regions. Subtlety rating (1-3) is assigned to each abnormal region, where 3 refers to obvious and 1 refers to subtle abnormalities. Performance is evaluated on normal and abnormal regions from an independent dataset of 900 images. These contain in total 454 normal and 1127 abnormal regions, which are divided into 3 subtlety categories containing 280, 527 and 320 abnormal regions, respectively. For normal regions, original/BSI CAD has an average abnormality score of 0.094+/-0.027/0.085+/-0.032 (p - 5.6×10-19). For abnormal regions, subtlety 1, 2, 3 categories have average abnormality scores for original/BSI of 0.155+/-0.073/0.156+/-0.089 (p = 0.73), 0.194+/-0.086/0.207+/-0.101 (p = 5.7×10-7), 0.225+/-0.119/0.247+/-0.117 (p = 4.4×10-7), respectively. Thus for normal regions, CAD scores slightly decrease when using BSI instead of the original images, and for abnormal regions, the scores increase slightly. We therefore conclude that the use of bone suppression results in slightly but significantly improved automated detection of textural abnormalities in chest radiographs.
Kapata, Nathan; Chanda-Kapata, Pascalina; Ngosa, William; Metitiri, Mine; Klinkenberg, Eveline; Kalisvaart, Nico; Sunkutu, Veronica; Shibemba, Aaron; Chabala, Chishala; Chongwe, Gershom; Tembo, Mathias; Mulenga, Lutinala; Mbulo, Grace; Katemangwe, Patrick; Sakala, Sandra; Chizema-Kawesha, Elizabeth; Masiye, Felix; Sinyangwe, George; Onozaki, Ikushi; Mwaba, Peter; Chikamata, Davy; Zumla, Alimuddin; Grobusch, Martin P.
Background Tuberculosis in Zambia is a major public health problem, however the country does not have reliable baseline data on the TB prevalence for impact measurement; therefore it was among the priority countries identified by the World Health Organization to conduct a national TB prevalence survey Objective To estimate the prevalence of tuberculosis among the adult Zambian population aged 15 years and above, in 2013–2014. Methods A cross-sectional population-based survey was conducted in 66 clusters across all the 10 provinces of Zambia. Eligible participants aged 15 years and above were screened for TB symptoms, had a chest x-ray (CXR) performed and were offered an HIV test. Participants with TB symptoms and/or CXR abnormality underwent an in-depth interview and submitted one spot- and one morning sputum sample for smear microscopy and liquid culture. Digital data collection methods were used throughout the process. Results Of the 98,458 individuals who were enumerated, 54,830 (55.7%) were eligible to participate, and 46,099 (84.1%) participated. Of those who participated, 45,633/46,099 (99%) were screened by both symptom assessment and chest x-ray, while 466/46,099 (1.01%) were screened by interview only. 6,708 (14.6%) were eligible to submit sputum and 6,154/6,708 (91.7%) of them submitted at least one specimen for examination. MTB cases identified were 265/6,123 (4.3%). The estimated national adult prevalence of smear, culture and bacteriologically confirmed TB was 319/100,000 (232-406/100,000); 568/100,000 (440-697/100,000); and 638/100,000 (502-774/100,000) population, respectively. The risk of having TB was five times higher in the HIV positive than HIV negative individuals. The TB prevalence for all forms was estimated to be 455 /100,000 population for all age groups. Conclusion The prevalence of tuberculosis in Zambia was higher than previously estimated. Innovative approaches are required to accelerate the control of TB. PMID:26771588
Lu, Yanjun; Li, Qian; Peng, Jing; Zhu, Yaowu; Wang, Feng; Wang, Chunyu; Wang, Xiong
The autophagy-related immunity-related GTPase family M protein, IRGM, plays an important role in the defense against tuberculosis (TB) infection. IRGM polymorphisms are associated with TB infection susceptibility, and recent studies demonstrate host genetic differences between active and latent TB. Here, we investigated the association between IRGM polymorphisms and TB infection type in a Chinese population. We recruited 268 and 321 patients with confirmed or latent TB, respectively, and 475 TB-free healthy controls. Three single nucleotide polymorphisms, rs10065172, rs10051924, and rs13361189 within IRGM were genotyped using TaqMan-based assays. Interferon-gamma release levels were tested by T-SPOT. rs10065172 (P = 0.024, OR 0.67 (95% CI 0.48-0.95)), rs10051924 (P = 0.01, OR 0.64 (95% CI 0.46-0.90)), and rs13361189 (P = 0.055, OR 0.72 (95% CI 0.51-1.01)) were associated with a protective role against latent TB progression. Haplotype analysis showed that TCC was protective for latent TB (P = 0.022, OR 0.74 (95% CI 0.57-0.96)) whereas TTC conferred a higher risk of active TB. Additionally, patients with the rs10065172 TT genotype had a higher response to TB specific antigens. Thus, IRGM polymorphism differences between latent and active TB suggests that genetic differences in autophagy might partly affect host TB infection status.
Ho, John L; Lapa e Silva, Jose Roberto
One-third of humans carry Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB) where microbe/host immune response interactions result in persistence or active TB. However, immune mediators associated with human TB remain poorly defined. Through a series of comparative studies of lung immune response of TB cases at the time of diagnosis and patients with other infectious lung diseases and volunteers, we found that TB cases expressed significantly higher levels of mediators that counteract Th1-type and innate immunity critical for containment of M. tuberculosis. Despite the concomitant heightened levels of Th1-type mediators, they are likely rendered ineffectual by high levels of intracellular (e.g., SOCS) and extracellular (e.g., IL-10) immune suppressors. These modulators are a direct response to M. tuberculosis as many suppressive factors declined to the levels of controls by 30 days of anti-TB treatment while most Th1-type and innate immune mediators rose above the pre-treatment levels. Parallel laboratory studies and monitored lung alveolar macrophage effector, nitric oxide synthase-2 (being shown critical for killing M. tuberculosis), support that M. tuberculosis actively promotes down-modulatory mediators to counteract Th1-type/innate immunity as an immunopathological strategy. Our studies highlight the potential application of immune mediators as surrogate markers for TB diagnosis or treatment response.
Wang, Jun; Huang, Yanfeng; Zhang, Aihua; Zhu, Chaomin; Yang, Zhenhua; Xu, Hongmei
In vitro and in animal studies have suggested an important role for the Mycobacterium tuberculosis PE_PGRS33 protein in the pathogenesis of TB. A significant level of PE_PGRS33 gene DNA polymorphism among clinical isolates from adult tuberculosis (TB) patients and its association with clinical and epidemiological phenotypes of the disease has been found. To better understand the role of PE_PGRS33 protein in the pathogenesis pediatric TB, we investigated DNA polymorphism of the PE_PGRS33 gene among 101 of pediatric TB patients' isolates and assessed the relationship between the PE_PGRS33 sequence variation and clinical characteristics of TB. Twelve different PE_PGRS33 sequence variations representing 12 different alleles were observed among the 101 M. tuberculosis clinical isolates investigated. Of these 101 isolates, 62(59.41%) had PE_PGRS33 alleles that would result in a change in the amino acid sequence of the PE_PGRS33 protein. The degree of DNA polymorphism within individual M. tuberculosis isolates from pediatric TB patients was remarkably lower than that previously found in M. tuberculosis isolates from adults TB patients. The frequency distribution of isolates having PE_PGRS33 gene sequence variations was similar between Beijing and non-Beijing families of the pathogen. Patients having TB meningitis and negative PPD skin test results appeared to be more likely to be infected by isolates having a mutant type of the PE_PGRS33 gene than patients who had no TB meningitis (OR 2.54, 95% CI [1.11-5.84]) and patients who had positive PPD-skin test results (OR 4.26, 95% CI [1.14-12.86]), respectively. This study provides new insight into the molecular pathogenesis of pediatric TB.
Master, Sharon S; Rampini, Silvana K; Davis, Alexander S; Keller, Christine; Ehlers, Stefan; Springer, Burkhard; Timmins, Graham S; Sander, Peter; Deretic, Vojo
Mycobacterium tuberculosis (Mtb) parasitizes host macrophages and subverts host innate and adaptive immunity. Several cytokines elicited by Mtb are mediators of mycobacterial clearance or are involved in tuberculosis pathology. Surprisingly, interleukin-1beta (IL-1beta), a major proinflammatory cytokine, has not been implicated in host-Mtb interactions. IL-1beta is activated by processing upon assembly of the inflammasome, a specialized inflammatory caspase-activating protein complex. Here, we show that Mtb prevents inflammasome activation and IL-1beta processing. An Mtb gene, zmp1, which encodes a putative Zn(2+) metalloprotease, is required for this process. Infection of macrophages with zmp1-deleted Mtb triggered activation of the inflammasome, resulting in increased IL-1beta secretion, enhanced maturation of Mtb containing phagosomes, improved mycobacterial clearance by macrophages, and lower bacterial burden in the lungs of aerosol-infected mice. Thus, we uncovered a previously masked role for IL-1beta in the control of Mtb and a mycobacterial system that prevents inflammasome and, therefore, IL-1beta activation.
Yang, Qianting; Xu, Qian; Chen, Qi; Li, Jin; Zhang, Mingxia; Cai, Yi; Liu, Haiying; Zhou, Yiping; Deng, Guofang; Deng, Qunyi; Zhou, Boping; Kornfeld, Hardy; Chen, Xinchun
Interferon-gamma Release Assays (IGRAs) significantly increases the possibility for early diagnosis of tuberculosis, but IGRAs alone cannot discriminate active TB from LTBI. Therefore, fast and reliable discrimination of active tuberculosis, especially bacteriology negative tuberculosis, from LTBI is a great necessity. Here we established an assay based on flow cytometric multiparameter assay assessing expression of CD161 along with CD3, CD4, and CD8, whereby a set of indices formulated by the percentages of CD3+CD161+, CD3+CD4+CD161+ and CD3+CD8+CD161+ T cells multiplied with lymphocyte/monocyte ratio were established. Application of the CD3+CD8+CD161+ index to compare a cohort of active tuberculosis with a cohort of LTBI or health control yielded 0.7662 (95% confidence interval [CI] 0.6559–0.8552) or 0.7922 (95% CI 0.6846–0.8763) for sensitivity and 0.9048 (95% CI 0.8209–0.9580) or 0.8939 (95% CI 0.8392–0.9349) for specificity when the TB cohort was AFB+; the corresponding results were 0.7481 (95% CI 0.6648–0.8198) or 0.7557 (95% CI 0.6730–0.8265) for sensitivity and 0.8571 (95% CI 0.7637–0.9239) or 0.8603 (95% CI 0.8008–0.9075) for specificity when the TB cohort was AFB−. Our results reveal that in combination with IGRAs, CD161-based indices provide a novel, fast diagnostic solution addressing the limitation of current tuberculosis diagnostics. PMID:26643453
Zolpidem (Ambien, 1) is an imidazo[1,2-a]pyridine-3-acetamide and an approved drug for the treatment of insomnia. As medicinal chemists enamored by how structure imparts biological function, we found it to have strikingly similar structure to the antitubercular imidazo[1,2-a]pyridine-3-carboxyamides. Zolpidem was found to have antituberculosis activity (MIC of 10–50 μM) when screened against replicating Mycobacterium tuberculosis (Mtb) H37Rv. Manipulation of the Zolpidem structure, notably, to structural isomers (“anagrams”), attains remarkably improved potency (5, MIC of 0.004 μM) and impressive potency against clinically relevant drug-sensitive, multi- and extensively drug-resistant Mtb strains (MIC < 0.03 μM). Zolpidem anagrams and analogues were synthesized and evaluated for their antitubercular potency, toxicity, and spectrum of activity against nontubercular mycobacteria and Gram-positive and Gram-negative bacteria. These efforts toward the rational design of isomeric anagrams of a well-known sleep aid underscore the possibility that further optimization of the imidazo[1,2-a]pyridine core may well “put TB to rest”. PMID:25984566
Podany, Anthony T.; Swindells, Susan
Tuberculosis (TB) has been a leading cause of death for more than a century. While effective therapies exist, treatment is long and cumbersome. TB control is complicated by the overlapping problems created by global inadequacy of public health infrastructures, the interaction of the TB and human immunodeficiency virus (HIV) epidemics, and the emergence of drug-resistant TB. After a long period of neglect, there is now significant progress in the development of novel treatment regimens for TB. Focusing on treatment for active disease, we review pathways to TB regimen development and the new and repurposed anti-TB agents in clinical development. PMID:27853505
Chaudhari, Aunp P; Ranganath, Ravi; Pavan, Malleshappa
Urogenital tuberculosis (TB) is a common late manifestation of an earlier symptomatic or asymptomatic pulmonary TB infection. A latency period ranging from 5 to 40 years between the time of the initial infection and the expression of urogenital TB frequently occurs. As one of the most common sites of involvement of extrapulmonary TB, urogenital TB accounts for 15% to 20% of the infections. We present a patient who had culture-negative active tubercular kidney disease due to silent tuberculous infection. Our case demonstrates the limitations of noninvasive testing in establishing the diagnosis of renal tuberculosis.
Maitra, Arundhati; Kamil, Tengku Karmila; Shaik, Monisha; Danquah, Cynthia Amaning; Chrzastek, Alina; Bhakta, Sanjib
To say that tuberculosis (TB) has regained a strong foothold in the global human health and wellbeing scenario would be an understatement. Ranking alongside HIV/AIDS as the top reason for mortality due to a single infectious disease, the impact of TB extends far into socio-economic context worldwide. As global efforts led by experts and political bodies converge to mitigate the predicted outcome of growing antimicrobial resistance, the academic community of students, practitioners and researchers have mobilised to develop integrated, inter-disciplinary programmes to bring the plans of the former to fruition. Enabling this crucial requirement for unimpeded dissemination of scientific discovery was the TB Summit 2016, held in London, United Kingdom. This report critically discusses the recent breakthroughs made in diagnostics and treatment while bringing to light the major hurdles in the control of the disease as discussed in the course of the 3-day international event. Conferences and symposia such as these are the breeding grounds for successful local and global collaborations and therefore must be supported to expand the understanding and outreach of basic science research.
Karki, Bindu; Kittel, Guenter; Bolokon, Ignatius; Duke, Trevor
Papua New Guinea is one of the 14 highest-burden countries for tuberculosis (TB) infection, but few community-based studies exist. We evaluated a low-cost method of active community case finding in Kabwum and Wasu in Morobe Province, Papua New Guinea. Over 3 months we visited 26 villages and screened adults and children for symptoms and signs of TB. Sputum samples were examined using smear microscopy. A total of 1700 people had chronic symptoms, of which 267 were suspicious for TB on further examination. Sputum from 230 symptomatic adults yielded 97 samples that were positive for acid-fast bacilli. In addition, 15 cases of extrapulmonary TB in adults and 17 cases of TB in children were identified. One hundred and thirty people were identified with active TB disease among the source population of approximately 17 000, giving an estimated prevalence of 765 per 100 000. One hundred and six (82%) cases were not previously diagnosed. The cost per case identified was US$146. It is feasible to conduct active community-based case finding and treatment initiation for TB with limited resources and in remote areas, and in Papua New Guinea the yield was high. Active case finding and follow-up of treatment in villages is needed to address the hidden burden of TB in Papua New Guinea and other high-burden Asia Pacific countries. PMID:28033717
Khan, Wasiq Mehmood; Smith, Helen; Qadeer, Ejaz
Objective To understand how national and provincial tuberculosis programme managers in Pakistan perceive and engage with the Stop TB strategy, its strengths, weaknesses and their experience in its implementation. National and provincial tuberculosis programme managers play an important role in effective implementation of the Stop TB strategy. Design A qualitative interview study was conducted with 10 national and provincial tuberculosis programme managers to understand how they perceive and engage with the Stop TB strategy, its strengths, weaknesses and their experience in its implementation. Managers were selected purposively; 10 managers were interviewed (six national staff and four from provincial level). Participants National and provincial tuberculosis programme managers in Pakistan. Managers were selected purposively; 10 managers were interviewed (six national staff and four from provincial level). Setting National and provincial tuberculosis programmes in Pakistan Main outcome measures 1. Knowledge and perceptions of national and provincial tuberculosis programme managers about the Stop TB strategy 2. Progress in implementing the strategy in Pakistan 3. Significant success factors 4. Significant implementation challenges 5. Lessons learnt to scale up successful implementation. Results The managers reported that most progress had been made in extending DOTS, health systems strengthening, public -private mixed interventions, MDR-TB care and TB/HIV care. The four factors that contributed significantly to progress were the availability of DOTS services, the public-private partnership approach, comprehensive guidance for TB control and government and donor commitment to TB control. Conclusion This study identified three main challenges as perceived by national and provincial tuberculosis programme managers in terms of implementing the Stop TB strategy: 1. Inadequate political commitment, 2. Issue pertaining to prioritisation of certain components in the TB
Porter, Brian O.; Chandrasekhar, Chockalingam; Venkatesan, Perumal; Menon, Pradeep A.; Subramanian, Sudha; Anbalagan, Selvaraj; Bhavani, Kannabiran P.; Sekar, Sathiyavelu; Padmapriyadarshini, Chandrasekaran; Kumar, Satagopan; Ravichandran, Narayanan; Raja, Krishnaraj; Bhanu, Kesavamurthy; Mahilmaran, Ayyamperumal; Sekar, Lakshmanan; Sher, Alan; Sereti, Irini; Swaminathan, Soumya
Background The incidence, manifestations, outcome and clinical predictors of paradoxical TB-IRIS in patients with HIV and culture confirmed pulmonary tuberculosis (PTB) in India have not been studied prospectively. Methods HIV+ patients with culture confirmed PTB started on anti-tuberculosis therapy (ATT) were followed prospectively after anti-retroviral therapy (ART) initiation. Established criteria for IRIS diagnosis were used including decline in plasma HIV RNA at IRIS event. Pre-ART plasma levels of interleukin (IL)-6 and C-reactive protein (CRP) were measured. Univariate and multivariate logistic regression models were used to evaluate associations between baseline variables and IRIS. Results Of 57 patients enrolled, 48 had complete follow up data. Median ATT-ART interval was 28 days (interquartile range, IQR 14–47). IRIS events occurred in 26 patients (54.2%) at a median of 11 days (IQR: 7–16) after ART initiation. Corticosteroids were required for treatment of most IRIS events that resolved within a median of 13 days (IQR: 9–23). Two patients died due to CNS TB-IRIS. Lower CD4+ T-cell counts, higher plasma HIV RNA levels, lower CD4/CD8 ratio, lower hemoglobin, shorter ATT to ART interval, extra-pulmonary or miliary TB and higher plasma IL-6 and CRP levels at baseline were associated with paradoxical TB-IRIS in the univariate analysis. Shorter ATT to ART interval, lower hemoglobin and higher IL-6 and CRP levels remained significant in the multivariate analysis. Conclusion Paradoxical TB–IRIS frequently complicates HIV-TB therapy in India. IL-6 and CRP may assist in predicting IRIS events and serve as potential targets for immune interventions. PMID:23691062
Sintayehu, Dejene W; Heitkönig, Ignas M A; Prins, Herbert H T; Tessema, Zewdu K; DE Boer, Willem F
Current theories on diversity-disease relationships describe host species diversity and species identity as important factors influencing disease risk, either diluting or amplifying disease prevalence in a community. Whereas the simple term 'diversity' embodies a set of animal community characteristics, it is not clear how different measures of species diversity are correlated with disease risk. We therefore tested the effects of species richness, Pielou's evenness and Shannon's diversity on bovine tuberculosis (bTB) risk in cattle in the Afar Region and Awash National Park between November 2013 and April 2015. We also analysed the identity effect of a particular species and the effect of host habitat use overlap on bTB risk. We used the comparative intradermal tuberculin test to assess the number of bTB-infected cattle. Our results suggested a dilution effect through species evenness. We found that the identity effect of greater kudu - a maintenance host - confounded the dilution effect of species diversity on bTB risk. bTB infection was positively correlated with habitat use overlap between greater kudu and cattle. Different diversity indices have to be considered together for assessing diversity-disease relationships, for understanding the underlying causal mechanisms. We posit that unpacking diversity metrics is also relevant for formulating disease control strategies to manage cattle in ecosystems characterized by seasonally limited resources and intense wildlife-livestock interactions.
Marín, Nancy D; París, Sara C; Rojas, Mauricio; García, Luis F
Tuberculosis (TB) is one of the most important infectious diseases around the world. Several studies have focused on the identification of correlates of protection against TB. Most of them have concentrated on the study of IFN-γ due to its robust association with protection against TB. However, given the complexity of the immune response elicited after Mtb infection, other cytokines should also be considered. In the present study, we evaluated Th1 and Th17 responses and their association with the protection or development of active disease. Therefore, non infected individuals (nonTBi), latently infected individuals (LTBi) and patients with active TB (ATB) were studied. The evaluation of the number of cytokine producing cells by ELISPOT showed a higher number of IFN-γ-producing cells in ATB patients, but no differences were found regarding the number of IL-17 producing cells among studied groups. The evaluation of IFN-γ, IL-2, TNF-α and IL-17 producing CD4+ and CD8+ T cells at 1 day and 6 days of stimulation with mycobacterial antigens suggests the presence of functional signatures associated with latency or active TB. The results presented herein suggest the possible use of the evaluation of Th1-type cytokines, such as IFN-γ and/or TNF-α, as a correlate of protection against TB; however, these results need to be validated for other groups.
Kaboru, Berthollet Bwira
Background and objective: The involvement of traditional healthcare providers (THPs) has been suggested among strategies to increase tuberculosis case detection. Burkina Faso has embarked on such an attempt. This study is a preliminary assessment of that model. Methods: Qualitative data were collected using unstructured key informant interviews with policy makers, group interviews with THPs and health workers, and field visits to THPs. Quantitative data were collected from program reports and the national tuberculosis (TB) control database. Results and analysis: The distribution of tasks among THPs, intermediary organizations and clinicians is appealing, especially the focus on active referral. THPs are offered incentives based on numbers of suspected cases confirmed by health workers at the clinic, based on microscopy results or clinical assessment. The positivity rate was 23% and 9% for 2006 and 2007, respectively. The contribution of the program to national case detection was estimated at 2% for 2006. Because it relied totally on donor funding, the program suffered from irregular disbursements, resulting in periodic decreases in activities and outcomes. Conclusions: The study shows that single interventions require a broader positive policy environment to be sustainable. Even if the active referral approach seems effective in enhancing TB case detection, more complex policy work and direction, domestic financial contribution and additional evidence for cost-effectiveness are needed before the approach can be established as a national policy. PMID:24359717
Khaliq, Aasia; Ravindran, Resmi; Hussainy, Syed Fahadulla; Krishnan, Viwanathan V; Ambreen, Atiqa; Yusuf, Noshin Wasim; Irum, Shagufta; Rashid, Abdul; Jamil, Muhammad; Zaffar, Fareed; Chaudhry, Muhammad Nawaz; Gupta, Puneet K; Akhtar, Muhammad Waheed; Khan, Imran H
Over 9 million new active tuberculosis (TB) cases emerge each year from an enormous pool of 2 billion individuals latently infected with Mycobacterium tuberculosis (M. tb.) worldwide. About 3 million new TB cases per year are unaccounted for, and 1.5 million die. TB, however, is generally curable if diagnosed correctly and in a timely manner. The current diagnostic methods for TB, including state-of-the-art molecular tests, have failed in delivering the capacity needed in endemic countries to curtail this ongoing pandemic. Efficient, cost effective and scalable diagnostic approaches are critically needed. We report a multiplex TB serology panel using microbead suspension array containing a combination of 11 M.tb. antigens that demonstrated overall sensitivity of 91% in serum/plasma samples from TB patients confirmed by culture. Group wise sensitivities for sputum smear positive and negative patients were 95%, and 88%, respectively. Specificity of the test was 96% in untreated COPD patients and 91% in general healthy population. The sensitivity of this test is superior to that of the frontline sputum smear test with a comparable specificity (30-70%, and 93-99%, respectively). The multiplex serology test can be performed with scalability from 1 to 360 patients per day, and is amenable to automation for higher (1000s per day) throughput, thus enabling a scalable clinical work flow model for TB endemic countries. Taken together, the above results suggest that well defined antibody profiles in blood, analyzed by an appropriate technology platform, offer a valuable approach to TB diagnostics in endemic countries.
Baral, S.; Shrestha, P.; Puri, M.; Kandel, S.; Lamichanne, B.; Elsey, H.; Brouwer, M.; Goel, S.; Chinnakali, P.
Setting: Twenty-two districts of Nepal, where intensified case-finding (ICF) activities for tuberculosis (TB) were implemented among risk groups under the TB REACH initiative in collaboration with the National TB Programme from July 2013 to November 2015. Objectives: To assess the yield of TB screening using an algorithm with smear microscopy followed by Xpert® MTB/RIF. Design: A descriptive study using routinely collected data. Results: Of 145 679 individuals screened, 28 574 (19.6%) had presumptive TB; 1239 (4.3%) of these were diagnosed with TB and 1195 (96%) were initiated on anti-tuberculosis treatment. The yield of screening was highest among people living with the human immunodeficiency virus (PLHIV) (6.1%), followed by household contacts (3.5%) and urban slum dwellers (0.5%). Among other risk groups, such as prisoners, factory workers, refugees and individuals with diabetes, the yield was less than 0.5%. The number needed to screen to diagnose an active TB case was 17 for PLHIV, 29 for household contacts and 197 for urban slum dwellers. Of 11 525 patients from ICF and the routine programme, 112 (1%) were diagnosed with multidrug-resistant TB. Conclusion: There was a substantial yield of TB cases among risk groups such as PLHIV and household contacts. Although the yield in urban slum dwellers was found to be moderate, some intervention should nonetheless be targeted because of the large population and poor access to care in this group. PMID:27358808
Delai, M Y; Gounder, S; Tayler-Smith, K; Van den Bergh, R; Harries, A D
Due to concerns about under-reporting of the tuberculosis (TB) case burden in Fiji, efforts have been put into national training, education and awareness activities in the formal health sector and among village health workers, health volunteers and the community since 2010. There has been an absolute increase in TB registrations, and TB case notification rates during the period of training activities in 2010 (21.3 per 100 000 population) and 2011 (23.6/100 000) were significantly increased compared with TB case notification rates in 2008 (12.4/100 000) and 2009 (14.6/100 000), when no training activities took place (P < 0.01). These findings support the use of ongoing training efforts.
Bell, Lucy C K; Pollara, Gabriele; Pascoe, Mellissa; Tomlinson, Gillian S; Lehloenya, Rannakoe J; Roe, Jennifer; Meldau, Richard; Miller, Robert F; Ramsay, Alan; Chain, Benjamin M; Dheda, Keertan; Noursadeghi, Mahdad
Increased risk of tuberculosis (TB) associated with HIV-1 infection is primarily attributed to deficient T helper (Th)1 immune responses, but most people with active TB have robust Th1 responses, indicating that these are not sufficient to protect against disease. Recent findings suggest that favourable outcomes following Mycobacterium tuberculosis infection arise from finely balanced inflammatory and regulatory pathways, achieving pathogen control without immunopathology. We hypothesised that HIV-1 and antiretroviral therapy (ART) exert widespread changes to cell mediated immunity, which may compromise the optimal host protective response to TB and provide novel insights into the correlates of immune protection and pathogenesis. We sought to define these effects in patients with active TB by transcriptional profiling of tuberculin skin tests (TST) to make comprehensive molecular level assessments of in vivo human immune responses at the site of a standardised mycobacterial challenge. We showed that the TST transcriptome accurately reflects the molecular pathology at the site of human pulmonary TB, and used this approach to investigate immune dysregulation in HIV-1/TB co-infected patients with distinct clinical phenotypes associated with TST reactivity or anergy and unmasking TB immune reconstitution inflammatory syndrome (IRIS) after initiation of ART. HIV-1 infected patients with positive TSTs exhibited preserved Th1 responses but deficient immunoregulatory IL10-inducible responses. Those with clinically negative TSTs revealed profound anergy of innate as well as adaptive immune responses, except for preservation of type 1 interferon activity, implicated in impaired anti-mycobacterial immunity. Patients with unmasking TB IRIS showed recovery of Th1 immunity to normal levels, but exaggerated Th2-associated responses specifically. These mechanisms of immune dysregulation were localised to the tissue microenvironment and not evident in peripheral blood. TST
Barr, David A.; Kamdolozi, Mercy; Nishihara, Yo; Ndhlovu, Victor; Khonga, Margaret; Davies, Geraint R.; Sloan, Derek J.
Summary Faster elimination of drug tolerant ‘persister’ bacteria may shorten treatment of tuberculosis (TB) but no method exists to quantify persisters in clinical samples. We used automated image analysis to assess whether studying growth characteristics of individual Mycobacterium tuberculosis colonies from sputum on solid media during early TB treatment facilitates ‘persister’ phenotyping. As Time to Detection (TTD) in liquid culture inversely correlates with total bacterial load we also evaluated the relationship between individual colony growth parameters and TTD. Sputum from TB patients in Malawi was prepared for solid and liquid culture after 0, 2 and 4 weeks of treatment. Serial photography of agar plates was used to measure time to appearance (lag time) and radial growth rate for each colony. Mixed-effects modelling was used to analyse changing growth characteristics from serial samples. 20 patients had colony measurements recorded at ≥1 time-point. Overall lag time increased by 6.5 days between baseline and two weeks (p = 0.0001). Total colony count/ml showed typical biphasic elimination, but long lag time colonies (>20days) had slower, monophasic decline. TTD was associated with minimum lag time (time to appearance of first colony1). Slower elimination of long lag time colonies suggests that these may represent a persister subpopulation of bacilli. PMID:27156626
Jimenez-Arellanes, Adelina; Meckes, Mariana; Ramirez, Raquel; Torres, Javier; Luna-Herrera, Julieta
The increase of multidrug-resistant Mycobacterium tuberculosis (MDR-TB) demands the search for alternative antimycobacterial drugs. The aim of this study was to evaluate plants used in Mexican traditional medicine to treat respiratory diseases for activity against MDR-TB. A group of 22 plants was screened for activity against Mycobacterium tuberculosis H37Rv and Mycobacterium avium at concentrations from 50 to 200 microg/mL. The antimycobacterial effect was determined by a microcolorimetric assay with Alamar blue dye. None of the aqueous extracts had antimycobacterial activity. Hexane extracts from Artemisia ludoviciana, Chamaedora tepejilote, Lantana hispida, Juniperus communis and Malva parviflora, and methanol extracts from Artemisia ludoviciana and Juniperus communis inhibited the growth of Mycobacterium tuberculosis. Mycobacterium avium was inhibited by Juniperus communis hexane extract and by Malva parviflora methanol extract. The active extracts were tested against monoresistant variants of Mycobacterium tuberculosis H37Rv (isoniazid, rifampin, streptomycin and ethambutol resistant) and the hexane extract of Lantana hispida showed the best activity. Lantana hispida hexane extract was also active against a group of MDR-TB clinical isolates. In contrast, it did not inhibit the growth of non-tuberculous mycobacteria. The hexane extract of Lantana hispida was fractionated by column chromatography and one of its fractions (FVI) inhibited the growth of all the MDR-TB clinical isolates at concentrations up to 25 microg/mL. This study supports the fact that selecting plants by ethnobotanical criteria enhances the probability of finding species with activity against mycobacteria, and our results point to Lantana hispida as an important source of potential compounds against MDR-TB.
Ben-Selma, Walid; Harizi, Hedi; Bougmiza, Iheb; Ben Kahla, Imen; Letaief, Mahmoud; Boukadida, Jalel
RANTES plays a pivotal role in attracting and activating various leukocyte populations that control Mycobacterium tuberculosis infection. The present study investigated the relationship between the RANTES polymorphisms (-28C/G; rs2280788, and -403G/A; rs2107538) and susceptibility to active tuberculosis (TB) in Tunisian populations. A total of 168 patients with pulmonary TB (pTB), 55 with extrapulmonary TB (epTB), and 150 control subjects were studied. Genotype analyses were carried out using polymerase chain reaction-restriction fragment length polymorphism method. We found that the -28 GG genotype was significantly associated with susceptibility to pTB (odds ratio [OR]=11.19; 95% confidence intervals [CI], 5.14-25; P corrected for the number of genotypes [Pc]=10(-8)) and epTB (OR=11.67; 95% CI, 4.74-29.33; Pc=10(-8)). However, the -28 CC genotype was found to be significantly associated with resistance to pTB (OR=0.08; 95% CI, 0.04-0.16; Pc=10(-8)) and epTB development (OR=0.11; 95% CI, 0.05-0.27; Pc=10(-8)). -403A allele was associated with increased risk development of epTB (OR=2.21; 95% CI, 1.18-4.14; p=0.007). G-G and A-C haplotypes and the AG/GC diplotype were associated with increase susceptibility to pTB (OR=7.88, 95% CI, 5.38-11.55; Pc=3.10(-8); OR=2.32, 95% CI, 1.32-4.11; Pc=3.10(-3); OR=13.26, 95% CI, 6.06-29.89; Pc=3.10(-8); respectively) and epTB (OR=6.64, 95% CI, 4-11.05; Pc=3.10(-8); OR=2.6, 95% CI, 1.26-5.35; Pc=12.10(-3); OR=11.26, 95% CI, 4.44-29.28; Pc=3.10(-8); respectively). Collectively, our findings suggested an association of the RANTES -28C/G and -403G/A functional polymorphisms with susceptibility to Mycobacterium tuberculosis infection in Tunisian populations.
Payen, M C; VAN Vooren, J P; Vandenberg, O; Clumeck, N; DE Wit, S
Tuberculosis (TB) remains a threat to public health and is the second cause of death due to a single infectious agent after HIV/AIDS. The worldwide distribution of TB is heterogeneous. The incidence is decreasing in most high-income regions, but the situation remains worrying in many parts of the world. The emergence of Mycobacterium tuberculosis strains resistant to key agents used in treatment (rifampin and isoniazid) contributes to TB transmission around the world. To achieve TB elimination, both high and low endemic countries must upscale their efforts to decrease disease transmission and improve cure rates. Management of drug-resistant TB is of particular importance. In this paper, we discuss the different models of care of multidrug-resistant TB (MDR-TB), the ethical considerations and the specific constraints present in high income countries. The management model chosen by the Belgian TB specialists in accordance with public health authorities as well as building of a specific MDR/XDR-TB isolation unit are also discussed.
Vial, F; Miguel, E; Johnston, W T; Mitchell, A; Donnelly, C A
Over the last couple of decades, the UK experienced a substantial increase in the incidence and geographical spread of bovine tuberculosis (TB), in particular since the epidemic of foot-and-mouth disease (FMD) in 2001. The initiation of the Randomized Badger Culling Trial (RBCT) in 1998 in south-west England provided an opportunity for an in-depth collection of questionnaire data (covering farming practices, herd management and husbandry, trading and wildlife activity) from herds having experienced a TB breakdown between 1998 and early 2006 and randomly selected control herds, both within and outside the RBCT (the so-called TB99 and CCS2005 case-control studies). The data collated were split into four separate and comparable substudies related to either the pre-FMD or post-FMD period, which are brought together and discussed here for the first time. The findings suggest that the risk factors associated with TB breakdowns may have changed. Higher Mycobacterium bovis prevalence in badgers following the FMD epidemic may have contributed to the identification of the presence of badgers on a farm as a prominent TB risk factor only post-FMD. The strong emergence of contact/trading TB risk factors post-FMD suggests that the purchasing and movement of cattle, which took place to restock FMD-affected areas after 2001, may have exacerbated the TB problem. Post-FMD analyses also highlighted the potential impact of environmental factors on TB risk. Although no unique and universal solution exists to reduce the transmission of TB to and among British cattle, there is an evidence to suggest that applying the broad principles of biosecurity on farms reduces the risk of infection. However, with trading remaining as an important route of local and long-distance TB transmission, improvements in the detection of infected animals during pre- and post-movement testing should further reduce the geographical spread of the disease.
Li, Fabin; Longuet, Christophe; Vernet, Guy; Goletti, Delia; Zhao, Yanlin; Lagrange, Philippe H.
Background Interferon-release assays (IGRAs) for diagnosing active pulmonary tuberculosis (PTB) are not yet fully validated, particularly in high TB-endemic areas as the People's Republic of China (PRC). The aim of this report was to assess the performance of the QuantiFERON-TB Gold In-tube (QFT-GIT) and tuberculin skin test (TST), in addition to microbiological results, as contributors for diagnosing active PTB in the PRC. Methods/Principal Findings A total of 300 PTB patients, 41 disease controls (DC) and 59 healthy community controls (HCC) were included prospectively between May 2010 and April 2011 from two provinces of the PRC (Heilongjiang and Zhejiang). The QFT-GIT and TST yielded an overall sensitivity for active TB of 80.9% and 86.2%, and a specificity of 36.6% and 26.8%, respectively. The province of origin and smear microscopy status did not significantly impact the diagnostic values for PTB. However, using the TST with a 10 mm cut-off point, a significantly higher proportion of LTBI was observed in the DC than the HCC (p=0.01). Discordant results between the QFT-GIT and TST were found among 1/3 of the PTB, HCC and DC. Two-thirds of the individuals presented TST-positive/QFT-GIT-negative discordant results. The TST-negative/QFT-GIT-positive result was not associated with age or bacillary load. Cumulative QFT-GIT and TST positive results increased the overall sensitivity (95.9%), but it was associated with a dramatic decrease of the overall specificity (24.8%) leading to a suboptimal PPV (80.1%) and a low NPV (61.1%). Conclusions/Significance The usefulness of the QFT-GIT to diagnose active TB in high TB-endemic countries remains doubtful because like the TST, the QFT-GIT cannot distinguish between LTBI and active TB. Used as single stand-alone tests, both the QFT-GIT and TST have very limited roles in the diagnosis of active PTB. However, the combined use of SM, the TST and QFT-GIT may allow for the exclusion of ATB. PMID:25867946
Bai, Xue-juan; Liang, Yan; Yang, You-rong; Feng, Jin-dong; Luo, Zhan-peng; Zhang, Jun-Xian; Wu, Xue-qiong
Latent tuberculosis infection (LTBI) constitutes the main reservoir for reactivation tuberculosis. The finding of potential biomarkers for differentiating between TB and LTBI is very necessary. In this study, the immunological characteristics and potential diagnostic utility of Rv2029c, Rv2628 and Rv1813c proteins were assessed. These three proteins stimulated PBMCs from ELISPOT-positive LTBI subjects produced higher levels of IFN-γ in comparison with TB patients and ELISPOT-negative healthy subjects (p<0.05). BCG vaccination and non-TB respiratory disease had little influence on the immunological responses of Rv2029c and Rv2628 proteins (p>0.05). The LTBI diagnostic performance of Rv2029c was higher than Rv2628 and Rv1813c by ROC evaluation. But Rv2628 had much higher specificity than Rv2029c in active TB patients and uninfected healthy subjects. The IgG level against Rv1813c was higher in the TB group than in LTBI and uninfected healthy subjects (p<0.05). These results suggest that T cell response to Rv2628 and antibody against Rv1813c might be applicable as biomarkers to distinguish TB from LTBI and uninfected individuals.
Zhang, Ting; Hu, Siyu; Li, Guoli; Li, Hui; Liu, Xiaoli; Niu, Jianjun; Wang, Feng; Wen, Huixin; Xu, Ye; Li, Qingge
Rapid and comprehensive detection of drug-resistance is essential for the control of tuberculosis, which has facilitated the development of molecular assays for the detection of drug-resistant mutations in Mycobacterium tuberculosis. We hereby assessed the analytical and clinical performance of an assay for streptomycin-resistant mutations. MeltPro TB/STR is a closed-tube, dual-color, melting curve analysis-based, real-time PCR test designed to detect 15 streptomycin-resistant mutations in rpsL 43, rpsL 88, rrs 513, rrs 514, rrs 517, and rrs 905-908 of M. tuberculosis. Analytical studies showed that the accuracy was 100%, the limit of detection was 50-500 bacilli per reaction, the reproducibility in the form of Tm variation was within 1.0 °C, and we could detect 20% STR resistance in mixed bacterial samples. The cross-platform study demonstrated that the assay could be performed on six models of real-time PCR instruments. A multicenter clinical study was conducted using 1056 clinical isolates, which were collected from three geographically different healthcare units, including 709 STR-susceptible and 347 STR-resistant isolates characterized on Löwenstein-Jensen solid medium by traditional drug susceptibility testing. The results showed that the clinical sensitivity and specificity of the MeltPro TB/STR was 88.8% and 95.8%, respectively. Sequencing analysis confirmed the accuracy of the mutation types. Among all the 8 mutation types detected, rpsL K43R (AAG → AGG), rpsL K88R (AAG → AGG) and rrs 514 A → C accounted for more than 90%. We concluded that MeltPro TB/STR represents a rapid and reliable assay for the detection of STR resistance in clinical isolates.
Noor, Rashed; Akhter, Safia; Rahman, Farjana; Munshi, Saurab Kishore; Kamal, S M Mostofa; Feroz, Farahnaaz
Emergence of extensively drug-resistant (XDR) tuberculosis (TB) in Bangladesh has increased as a result of the inadequate management of TB-infected individuals. The present study attempted to detect the frequency of multidrug resistance (MDR) among the TB patients categorically from relapse, category I failure, category II failure, and return after default category I and II cases, using the conventional drug susceptibility test. Among 100 sputum specimens from all four categories, 81 and 84 positive cases were identified under light-emitting diode fluorescence microscope and the Lowenstein-Jensen (L-J) culture method, respectively. Of 84 culture-positive cases, elevated resistance was observed against isoniazid (89.3 %) and rifampicin (91.7 %) compared to that against streptomycin (53.6 %) and ethambutol (47.7 %). Resistance against ofloxacin, gatifloxacin, and kanamycin was 8.3, 5.9, and 2.4 %, consecutively. Fifty-nine cases were found to be MDR-TB. Two of these cases, which showed resistance against kanamycin and ofloxacin, were further identified as XDR. The proportion of XDR cases was more likely to be in the return after default category I and II cases.
Thapa, B; Chadha, S S; Das, A; Mohanty, S; Tonsing, J
Data from surveys on knowledge, attitudes and practice (KAP) on tuberculosis (TB) conducted under the Axshya project at two time points (baseline 2010-2011 and mid-line 2012-2013) were analysed for changes in coverage and equity of TB awareness after project interventions. Overall coverage increased from 84% at baseline to 88% at midline (5% increase, P < 0.05). In comparison to baseline results, coverage at the midline survey had significantly increased, from 81% to 87% among the rural population, from 81% to 86% among women, from 73% to 85% in the ⩾55 years age group, from 71% to 80% among illiterates and from 73% to 81% in the south zone (P < 0.05). The equity gap among the different study groups (settlement, sex, age, education and zones) decreased from 6-23% at baseline to 3-11% during the midline survey. The maximum decline was observed for type of settlement (rural vs. urban), from 10% to 3% (P < 0.05). This community-driven TB control project has achieved high and equitable coverage of TB awareness, offering valuable lessons for the global community.
Garcia, Benjamin J; Loxton, Andre G; Dolganov, Gregory M; Van, Tran T; Davis, J Lucian; de Jong, Bouke C; Voskuil, Martin I; Leach, Sonia M; Schoolnik, Gary K; Walzl, Gerhard; Strong, Michael; Walter, Nicholas D
Pathogen-targeted transcriptional profiling in human sputum may elucidate the physiologic state of Mycobacterium tuberculosis (M. tuberculosis) during infection and treatment. However, whether M. tuberculosis transcription in sputum recapitulates transcription in the lung is uncertain. We therefore compared M. tuberculosis transcription in human sputum and bronchoalveolar lavage (BAL) samples from 11 HIV-negative South African patients with pulmonary tuberculosis. We additionally compared these clinical samples with in vitro log phase aerobic growth and hypoxic non-replicating persistence (NRP-2). Of 2179 M. tuberculosis transcripts assayed in sputum and BAL via multiplex RT-PCR, 194 (8.9%) had a p-value <0.05, but none were significant after correction for multiple testing. Categorical enrichment analysis indicated that expression of the hypoxia-responsive DosR regulon was higher in BAL than in sputum. M. tuberculosis transcription in BAL and sputum was distinct from both aerobic growth and NRP-2, with a range of 396-1020 transcripts significantly differentially expressed after multiple testing correction. Collectively, our results indicate that M. tuberculosis transcription in sputum approximates M. tuberculosis transcription in the lung. Minor differences between M. tuberculosis transcription in BAL and sputum suggested lower oxygen concentrations or higher nitric oxide concentrations in BAL. M. tuberculosis-targeted transcriptional profiling of sputa may be a powerful tool for understanding M. tuberculosis pathogenesis and monitoring treatment responses in vivo.
Richter, Linda M.; Lönnroth, Knut; Desmond, Chris; Jackson, Robin; Jaramillo, Ernesto; Weil, Diana
People with TB and/or HIV frequently experience severe economic barriers to health care, including out-of-pocket expenses related to diagnosis and treatment, as well as indirect costs due to loss of income. These barriers can both aggravate economic hardship and prevent or delay diagnosis, treatment and successful outcome, leading to increased transmission, morbidity and mortality. WHO, UNAIDS and the ILO argue that economic support of various kinds is essential to enable vulnerable people to protect themselves from infection, avoid delayed diagnosis and treatment, overcome barriers to adherence, and avert destitution. This paper analyses successful country proposals to the Global Fund to Fight AIDS, Tuberculosis and Malaria that include economic support in Rounds 7 and 10; 36 and 20 HIV and TB grants in Round 7 and 32 and 26, respectively, in Round 10. Of these, up to 84 percent included direct or indirect economic support for beneficiaries, although the amount constituted a very small proportion of the total grant. In TB grants, the objectives of economic support were generally clearly stated, and focused on mechanisms to improve treatment uptake and adherence, and the case was most clearly made for MDR-TB patients. In HIV grants, the objectives were much broader in scope, including mitigation of adverse economic and social effects of HIV and its treatment on both patients and families. The analysis shows that economic support is on the radar for countries developing Global Fund proposals, and a wide range of economic support activities are in place. In order to move forward in this area, the wealth of country experience that exists needs to be collated, assessed and disseminated. In addition to trials, operational research and programme evaluations, more precise guidance to countries is needed to inform evidence-based decision about activities that are cost-effective, affordable and feasible. PMID:24489702
Performance of a lateral flow immunochromatography test for the rapid diagnosis of active tuberculosis in a large multicentre study in areas with different clinical settings and tuberculosis exposure levels
Manga, Selene; Perales, Rocio; Reaño, Maria; D’Ambrosio, Lia
Background Tuberculosis (TB) continues to cause an outsized burden of morbidity and mortality worldwide, still missing efficient and largely accessible diagnostic tools determining an appropriate control of the disease. Serological tests have the potentially to impact TB diagnosis, in particular in extreme clinical settings. Methods The diagnostic performances of the TB-XT HEMA EXPRESS (HEMA-EXPRESS) immunochromatographic rapid test for active TB diagnosis, based on use of multiple Mycobacterium tuberculosis (MTB) specific antigens, have been evaluated in a large study multicentre TB case-finding study, in populations with different exposure level to TB. A total of 1,386 subjects were enrolled in the six participating centres in Peru: 290 active-TB and 1,096 unaffected subjects. Results The TB prevalence (overall 20.5%) varied between 4.0% and 41.1% in the different study groups. Overall, the HEMA-EXPRESS test had 30.6% sensitivity (range 3.9–77.9%) and 84.6% specificity (range 51.6–97.3%). A significant inverse correlation between test accuracy (overall 73.5%, range 40.4–96.4%) and TB prevalence in the various study populations was observed (Pearson’s r=−0.7985; P=0.05). Conclusions HEMA-EXPRESS, is rapid and relatively inexpensive test suitable for routine use in TB diagnosis. In low TB prevalence conditions, test performance appears in line with WHO Target Product Profile for TB diagnostics. Performances appear suboptimal in high TB prevalence settings. Appropriate set-up in operative clinical settings has to be considered for novel serological tests for TB diagnosis, particularly for formats suitable for point-of-care use. PMID:28066611
Sultan, B; Benn, P; Mahungu, T; Young, M; Mercey, D; Morris-Jones, S; Miller, R F
There is currently no 'gold standard' for diagnosis of latent tuberculosis infection (LTBI), and both the tuberculin skin test and interferon-gamma release assays (IGRAs) are used for diagnosis; the latter have a higher sensitivity than tuberculin skin tests for diagnosis of LTBI in HIV-infected individuals with lower CD4 counts. No evidence base exists for selection of IGRA methodology to identify LTBI among human immunodeficiency virus-infected patients in the UK. We prospectively evaluated two commercially available IGRA methods (QuantiFERON-TB Gold In Tube [QFG] and T-SPOT.TB) for testing LTBI among HIV-infected patients potentially nosocomially exposed to an HIV-infected patient with 'smear-positive' pulmonary tuberculosis. Among the exposed patients median CD4 count was 550 cells/µL; 105 (90%) of 117 were receiving antiretroviral therapy, of who 104 (99%) had an undetectable plasma HIV load. IGRAs were positive in 12 patients (10.3%); QFG positive in 11 (9.4%) and T-SPOT.TB positive in six (5.1%); both IGRAs were positive in five patients (4.3%). There was one indeterminate QFG and one borderline T-SPOT.TB result. Concordance between the two IGRAs was moderate (κ = 0.56, 95% confidence interval = 0.27-0.85). IGRAs were positive in only 4 (29%) of 14 patients with previous culture-proven tuberculosis. No patient developed tuberculosis during 20 months of follow-up.
Castro, Kenneth G; Jaffe, Harold W
Our understanding of tuberculosis (TB) transmission dynamics has been refined by genotyping of Mycobacterium tuberculosis strains. The National Tuberculosis Genotyping and Surveillance Network was designed and implemented to systematically evaluate the role of genotyping technology in improving TB prevention and control activities. Genotyping proved a useful adjunct to investigations of outbreaks, unusual clusters, and laboratory cross-contamination.
Rate of tuberculosis infection in children and adolescents with household contact with adults with active pulmonary tuberculosis as assessed by tuberculin skin test and interferon-gamma release assays.
Ferrarini, M A G; Spina, F G; Weckx, L Y; Lederman, H M; De Moraes-Pinto, M I
Tuberculosis (TB) infection was evaluated in Brazilian immunocompetent children and adolescents exposed and unexposed (control group) to adults with active pulmonary TB. Both groups were analysed by clinical and radiological assessment, TST, QFT-IT and T-SPOT.TB. The three tests were repeated after 8 weeks in the TB-exposed group if results were initially negative. Individuals with latent tuberculosis infection (LTBI) were treated and tests were repeated after treatment. Fifty-nine TB-exposed and 42 controls were evaluated. Rate of infection was 69·5% and 9·5% for the exposed and control groups, respectively. The exposed group infection rate was 61% assessed by TST, 57·6% by T-SPOT.TB, and 59·3%, by QFT-IT. No active TB was diagnosed. Agreement between the three tests was 83·1% and 92·8% in the exposed and control groups, respectively. In the exposed group, T-SPOT.TB added four TB diagnoses [16%, 95% confidence interval (CI) 1·6-30·4] and QFT-IT added three TB diagnoses (12%, 95% CI 0-24·7) in 25 individuals with negative tuberculin skin test (TST). Risk factors associated to TB infection were contact with an adult with active TB [0-60 days: odds ratio (OR) 6·9; >60 days: OR 27·0] and sleeping in the same room as an adult with active TB (OR 5·2). In Brazilian immunocompetent children and adolescents, TST had a similar performance to interferon-gamma release assays and detected a high rate of LTBI.
Talwar, Harvinder; Talreja, Jaya; Samavati, Lobelia
One-third of the world's population is infected with tuberculosis, only 10% will develop active disease and the remaining 90% is considered to have latent TB (LTB). While active TB is contagious and can be lethal, the LTB can evolve to active TB. The diagnosis of TB can be challenging, especially in the early stages, due to the variability in presentation and nonspecific signs and symptoms. Currently, we have limited tools available to diagnose active TB, predict treatment efficacy and cure of active tuberculosis, the reactivation of latent tuberculosis infection, and the induction of protective immune responses through vaccination. Therefore, the identification of robust and accurate tuberculosis-specific biomarkers is crucial for the successful eradication of TB. In this commentary, we summarized the available methods for diagnosis and differentiation of active TB from LTB and their limitations. Additionally, we present a novel peptide microarray platform as promising strategy to identify TB biomarkers. PMID:27867751
Wang, Qi; Hu, Yong Liang; Zhu, Baoli; Woo, Patrick C. Y.
Background Information on treatment outcomes among hospitalized patients with multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) are scarce in China. Methodology/Principal Findings We conducted this retrospective study to analyze the characteristics and treatment outcomes in MDR- and XDR-TB patients in the 309 Hospital in Beijing, China during 1996–2009. Socio-demographic and clinical data were retrieved from medical records and analyzed. Logistic regression analysis was performed to identify risk factors associated with poor treatment outcomes and Cox proportional hazards regression model was further used to determine risk factors associated with death in TB patients. Among the 3,551 non-repetitive hospitalized TB patients who had drug susceptibility testing (DST) results, 716 (20.2%) had MDR-TB and 51 (1.4%) had XDR-TB. A total of 3,270 patients who had medical records available were used for further analyses. Treatment success rates (cured and treatment completed) were 90.9%, 53.4% and 29.2% for patients with non-MDR-TB, patients with MDR-TB excluding XDR-TB and patients with XDR-TB, respectively. Independent risk factors associated with poor treatment outcomes in MDR-TB patients included being a migrant (adjusted OR = 1.77), smear-positivity at treatment onset (adjusted OR = 1.94) and not receiving 3 or more potentially effective drugs (adjusted OR = 3.87). Independent risk factors associated with poor treatment outcomes in XDR-TB patients were smear-positivity at treatment onset (adjusted OR = 10.42) and not receiving 3 or more potentially effective drugs (adjusted OR = 14.90). The independent risk factors associated with death in TB patients were having chronic obstructive pulmonary disease (adjusted HR = 5.25) and having hypertension (adjusted HR = 4.31). Conclusions/Significance While overall satisfactory treatment success for non-MDR-TB patients was achieved, more intensive efforts
Mancuso, James D; Aaron, Christopher L
Members of the Armed Forces represent a segment of the U.S. population that may be at increased risk for tuberculosis (TB) infection, disease, and transmission due to overseas service in endemic areas and residence in congregate settings. The purpose of this study was to examine recent surveillance trends and risk factors associated with TB disease in the active component U.S. military. The rate of TB in the U.S. military -0.6 per 100,000 population (n=128) over the interval from 1998 to 2012 - was lower than the age-adjusted rate among the U.S. population (adjusted rate ratio=0.20) over the same time interval. During the last five years of the surveillance period, the most common factor associated with the diagnosis of TB disease during military service was latent infection at time of accession; also, as many as nine (24%) cases of TB were associated with deployment to Iraq or other military exposures. TB control activities should continue to mitigate unique military exposures such as crowding during recruit training and deployments to TB endemic areas.
Khan, Kamran; Rea, Elizabeth; McDermaid, Cameron; Stuart, Rebecca; Chambers, Catharine; Wang, Jun; Chan, Angie; Gardam, Michael; Jamieson, Frances; Yang, Jae; Hwang, Stephen W
While tuberculosis (TB) in Canadian cities is increasingly affecting foreign-born persons, homeless persons remain at high risk. To assess trends in TB, we studied all homeless persons in Toronto who had a diagnosis of active TB during 1998-2007. We compared Canada-born and foreign-born homeless persons and assessed changes over time. We identified 91 homeless persons with active TB; they typically had highly contagious, advanced disease, and 19% died within 12 months of diagnosis. The proportion of homeless persons who were foreign-born increased from 24% in 1998-2002 to 39% in 2003-2007. Among foreign-born homeless persons with TB, 56% of infections were caused by strains not known to circulate among homeless persons in Toronto. Only 2% of infections were resistant to first-line TB medications. The rise in foreign-born homeless persons with TB strains likely acquired overseas suggests that the risk for drug-resistant strains entering the homeless shelter system may be escalating.
Al Wakeel, Jamal Saleh; Makoshi, Ziyad; Al Ghonaim, Mohammed; Al Harbi, Ali; Al Suwaida, Abdulkareem; Algahtani, Farjah; Al Hedaithy, Mogbil; Almogairin, Sultan; Abdullah, Sami
BACKGROUND AND AIM: Screening for tuberculosis (TB) is a key strategy for controlling infection. This study aimed to detect latent TB among dialysis patients. METHODS: This is a prospective study conducted in King Saud University, Riyadh involving hemodialysis (HD) and peritoneal dialysis (PD) patients aged ≥18 years. Patients were screened for latent TB infection (LTBI) using both TBskin test (TST) and QuantiFERONTB Gold In-Tube test (QFT-GIT). All participants were followed-up clinically and radiologically every 3 months for 2 years. RESULTS: A total of 243 (181 HD and 62 PD) patients were included and 112(46.1%) were males. 45.3% showed positive QFT in HD patients with sensitivity of 91.7%, specificity of 71.4%, positive predictive value (PPV) of 19.5%, and negative predictive value (NPV) of 91.1%. TST results in HD showed that positive TST was 17.4%, sensitivity was 63.2%, specificity was 95.5%, PPV was 51.5%, and NPV was 91.1%. Five (8.1%) showed positive QFT in PD patients with sensitivity of 7.7%, specificity of 91.8%, PPV of 6.6%, and NPV of 92.3%. TST results in PD showed that positive TST was 9.8%, sensitivity was 35.7%, specificity was 97.9%, PPV was 55.8%, and NPV was 93.3%. Previous TB infection was significantly correlated with QFT only in HD patients, but significantly associated with TST in both HD and PD patients. Also in HD, QFT was significantly associated with TST (P = 0.043). CONCLUSIONS: Due to high variability of QFT-GIT sensitivity, we recommend its use for its NPV and to use either TST or QFT in screening latent TB. PMID:26664568
... known as: Purified Protein Derivative; PPD; Mantoux; Latent Tuberculosis Infection Test; Interferon-gamma Release Assays; IGRA; T- ... else I should know? How is it used? Tuberculosis (TB) screening tests are not used as general ...
Martínez-Jiménez, Francisco; Papadatos, George; Yang, Lun; Wallace, Iain M.; Kumar, Vinod; Pieper, Ursula; Sali, Andrej; Brown, James R.; Overington, John P.; Marti-Renom, Marc A.
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), infects an estimated two billion people worldwide and is the leading cause of mortality due to infectious disease. The development of new anti-TB therapeutics is required, because of the emergence of multi-drug resistance strains as well as co-infection with other pathogens, especially HIV. Recently, the pharmaceutical company GlaxoSmithKline published the results of a high-throughput screen (HTS) of their two million compound library for anti-mycobacterial phenotypes. The screen revealed 776 compounds with significant activity against the M. tuberculosis H37Rv strain, including a subset of 177 prioritized compounds with high potency and low in vitro cytotoxicity. The next major challenge is the identification of the target proteins. Here, we use a computational approach that integrates historical bioassay data, chemical properties and structural comparisons of selected compounds to propose their potential targets in M. tuberculosis. We predicted 139 target - compound links, providing a necessary basis for further studies to characterize the mode of action of these compounds. The results from our analysis, including the predicted structural models, are available to the wider scientific community in the open source mode, to encourage further development of novel TB therapeutics. PMID:24098102
Rodrigues-Junior, Valnês S; Villela, Anne D; Gonçalves, Raoni S B; Abbadi, Bruno Lopes; Trindade, Rogério Valim; López-Gavín, Alexandre; Tudó, Griselda; González-Martín, Julian; Basso, Luiz Augusto; de Souza, Marcus V N; Campos, Maria Martha; Santos, Diógenes Santiago
Repurposing of drugs to treat tuberculosis (TB) has been considered an alternative to overcome the global TB epidemic, especially to combat drug-resistant forms of the disease. Mefloquine has been reported as a potent drug to kill drug-resistant strains of Mycobacterium tuberculosis. In addition, mefloquine-derived molecules have been synthesised and their effectiveness against mycobacteria has been assessed. In this work, we demonstrate for the first time the activities of mefloquine and its oxazolidine derivative compound 1E in a murine model of TB infection following administration of both drugs by the oral route. The effects of associations between mefloquine or 1E with the clinically used antituberculosis drugs isoniazid, rifampicin, ethambutol, moxifloxacin and streptomycin were also investigated. Importantly, combination of mefloquine with isoniazid and of 1E with streptomycin showed a two-fold decrease in their minimum inhibitory concentrations (MICs). Moreover, no tested combinations demonstrated antagonist interactions. Here we describe novel evidence on the activity of mefloquine and 1E against a series of quinolone-resistant M. tuberculosis strains. These data show MICs against quinolone-resistant strains (0.5-8 µg/mL) similar to or lower than those previously reported for multidrug-resistant strains. Taking these results together, we can suggest the use of mefloquine or 1E in combination with clinically available drugs, especially in the case of resistant forms of TB.
Maglione, Paul J; Xu, Jiayong; Casadevall, Arturo; Chan, John
The critical role of cellular immunity during tuberculosis (TB) has been extensively studied, but the impact of Abs upon this infection remains poorly defined. Previously, we demonstrated that B cells are required for optimal protection in Mycobacterium tuberculosis-infected mice. FcgammaR modulate immunity by engaging Igs produced by B cells. We report that C57BL/6 mice deficient in inhibitory FcgammaRIIB (RIIB-/-) manifested enhanced mycobacterial containment and diminished immunopathology compared with wild-type controls. These findings corresponded with enhanced pulmonary Th1 responses, evidenced by increased IFN-gamma-producing CD4+ T cells, and elevated expression of MHC class II and costimulatory molecules B7-1 and B7-2 in the lungs. Upon M. tuberculosis infection and immune complex engagement, RIIB-/- macrophages produced more of the p40 component of the Th1-promoting cytokine IL-12. These data strongly suggest that FcgammaRIIB engagement can dampen the TB Th1 response by attenuating IL-12p40 production or activation of APCs. Conversely, C57BL/6 mice lacking the gamma-chain shared by activating FcgammaR had enhanced susceptibility and exacerbated immunopathology upon M. tuberculosis challenge, associated with increased production of the immunosuppressive cytokine IL-10. Thus, engagement of distinct FcgammaR can divergently affect cytokine production and susceptibility during M. tuberculosis infection.
Tola, Habteyes Hailu; Tol, Azar; Shojaeizadeh, Davoud; Garmaroudi, Gholamreza
This systematic review intended to combine factors associated with tuberculosis treatment non-adherence and lost to follow up among TB patients with/without HIV in developing countries. Comprehensive remote electronic databases (MEDLINE, (PMC, Pub Med Central), Google scholar and Web of science) search was conducted using the following keywords: Tuberculosis, treatment, compliance, adherence, default, behavioural factors and socioeconomic factors. All types of studies intended to assess TB treatment non-adherence and lost to follow up in developing countries among adult TB patient from 2008 to data extraction date were included. Twenty-six original and one-reviewed articles, which meet inclusion criteria, were reviewed. TB treatment non-adherence and lost to follow up were continued across developing countries. The main factors associated with TB treatment non-adherence and lost to follow up were socioeconomic factors: lack of transportation cost, lack of social support, and patients-health care worker poor communication. Behavioural factors were Feeling better after few weeks of treatments, tobacco and alcohol use, knowledge deficit about duration of treatment and consequences of non-adherence and lost to follow up. TB treatment non-adherence and lost to follow up were continued across developing countries throughout the publication years of reviewed articles. Numerous, socioeconomic and behavioural factors were influencing TB treatment adherence and lost to follow up. Therefore, well understanding and minimizing of the effect of these associated factors is very important to enhance treatment adherence and follow up completion in developing countries.
Nakiyingi, Lydia; Bwanika, John Mark; Kirenga, Bruce; Nakanjako, Damalie; Katabira, Catherine; Lubega, Gloria; Sempa, Joseph; Nyesiga, Barnabas; Albert, Heidi; Manabe, Yukari C.
Introduction The existing diagnostic algorithms for sputum smear-negative tuberculosis (TB) are complicated, time-consuming, and often difficult to implement. The decision to initiate TB treatment in resource-limited countries is often largely based on clinical predictors. We sought to determine the clinical predictors and accuracy of empiric TB treatment initiation in HIV-infected sputum smear-negative TB suspects using sputum culture as a reference standard. Setting Out-patient HIV-TB integrated urban clinic in Kampala, Uganda. Methods HIV-infected TB suspects were screened using sputum smear microscopy, and mycobacterial sputum liquid and solid cultures were performed. Smear results were made available to the clinician who made a clinical decision on empiric TB treatment initiation for sputum smear-negative patients. Clinic records were reviewed for patients whose sputum smears were negative to collect data on socio-demographics, TB symptomatology, chest X-ray findings, CD4 cell counts and TB treatment initiation. Results Of 253 smear-negative TB suspects, 56% (142/253) were females, median age 38 IQR (31–44) years, with a median CD4 cell count of 291 IQR (150–482) cells/mm3. Of the 85 (33.6%) smear-negative patients empirically initiated on TB treatment, 35.3% (n = 30) were sputum culture positive compared to only 18 (10.7%) of the 168 untreated patients (p<0.001). Abnormal chest X-ray [aOR 10.18, 95% CI (3.14–33.00), p<0.001] and advanced HIV clinical stage [aOR 3.92, 95% CI (1.20–12.85), p = 0.024] were significantly associated with empiric TB treatment initiation. The sensitivity and specificity of empiric TB treatment initiation in the diagnosis of TB in HIV-infected patients after negative smear microscopy was 62.5% and 73.7% respectively. Conclusion In resource-limited settings, clinically advanced HIV and abnormal chest X-ray significantly predict a clinical decision to empirically initiate TB treatment in smear-negative HIV
Wu, Ping-Hsun; Lin, Yi-Ting; Yang, Yi-Hsin; Lin, Yu-Chih; Lin, Yi-Ching
The risk of active tuberculosis (TB) in patients with dermatomyositis (DM) is poorly understood. The cohort study aimed to investigate the association between DM and the risk of active TB disease. We conducted a population based study on 4,958 patients with newly diagnosed DM and 19,832 matched controls according to age, sex, and index date between 1998 and 2008. The hazard ratios (HRs) and cumulative incidences of active TB disease between DM patients and controls were analyzed. During the study period, a total of 85 (1.7%) DM patients developed active TB disease, which was significantly higher than that of non-DM patients (0.64%). The incidence rate of active TB disease was higher among DM patients than controls (incidence rate ratio 2.95; 95% confidence interval [CI], 2.24 to 3.88). The Cox regression model demonstrated significantly higher active TB disease rate among DM patients compared with controls (adjusted HR, 2.64; 95% CI, 1.97 to 3.54; p < 0.001) after adjusting for age, sex, and underlying medical disorders. The most significant risk factors for developing active TB included male sex, diabetes mellitus comorbidity, and use of corticosteroids and azathioprine in DM patients. In conclusion, DM patients are at a greater risk for active TB disease. PMID:26573418
Migrant Clinicians Network, Inc., Austin, TX.
A comprehensive tracking and referral network that helps provide continuity of care for mobile populations with active tuberculosis (TB) or TB infection is considered essential for effective treatment of TB. However, the interstate referral system that exists between state health departments has been highly inefficient for serving migrant…
Seyhan, Ekrem Cengiz; Gunluoglu, Gulşah; Gunluoglu, Mehmet Zeki; Tural, Seda; Sökücü, Sinem
BACKGROUND: Hemodialysis (HD) patients are at increased risk of reactivation of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in HD patients. AIM: In our study, we evaluated the value of the TST and QFT-G In-Tube (QFG-IT) test in the development of active tuberculosis (TB), in the HD patients, and in healthy controls. METHODS: The study enrolled 95 HD patients and ninety age-matched, healthy controls. The TST and QFG-IT were performed. All the subjects were followed up 5 years for active TB disease. RESULTS: Compared to the healthy controls, a high prevalence of LTBI was found in the HD patients by QFG-IT (41% vs. 25%). However, no significant difference was detected by TST (32% vs. 31%). Four HD patients and one healthy control progressed to active TB disease within the 5-year follow-up. For active TB discovered subjects, QFG-IT was positive in all, but TST was positive in two (one patient and one healthy control). In HD patients; sensitivity, specificity, positive and negative predictive values of QFG-IT, and TST for active TB was 100% and 25%, 62% and 67%, 10%, and 3%, and 100% and 95%, respectively. Receiver operating curve analysis revealed that the results are significantly different (P = 0.04). CONCLUSION: QFG-IT test is a more useful diagnostic method than TST for detecting those who will progress to active TB in HD patients. PMID:27168859
Xia, Xin; Pethe, Kevin; Kim, Ryangyeo; Ballell, Lluis; Barros, David; Cechetto, Jonathan; Jeon, HeeKyoung; Kim, Kideok; Garcia-Bennett, Alfonso E.
Tuberculosis is a major problem in public health. While new effective treatments to combat the disease are currently under development, they tend suffer from poor solubility often resulting in low and/or inconsistent oral bioavailability. Mesoporous materials are here investigated in an in vitro intracellular assay, for the effective delivery of compound PA-824; a poorly soluble bactericidal agent being developed against Tuberculosis (TB). Mesoporous materials enhance the solubility of PA-824; however, this is not translated into a higher antibacterial activity in TB-infected macrophages after 5 days of incubation, where similar values are obtained. The lack of improved activity may be due to insufficient release of the drug from the mesopores in the context of the cellular environment. However, these results show promising data for the use of mesoporous particles in the context of oral delivery with expected improvements in bioavailability.
Harries, Anthony D.; Hargreaves, Nicola J.; Chimzizi, Rehab; Salaniponi, Felix M.
HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome) and TB (tuberculosis) are two of the world's major pandemics, the brunt of which falls on sub-Saharan Africa. Efforts aimed at controlling HIV/AIDS have largely focused on prevention, little attention having been paid to care. Work on TB control has concentrated on case detection and treatment. HIV infection has complicated the control of tuberculosis. There is unlikely to be a decline in the number of cases of TB unless additional strategies are developed to control both this disease and HIV simultaneously. Such strategies would include active case-finding in situations where TB transmission is high, the provision of a package of care for HIV-related illness, and the application of highly active antiretroviral therapy. The latter is likely to have the greatest impact, but for this therapy to become more accessible in Africa the drugs would have to be made available through international support and a programme structure would have to be developed for its administration. It could be delivered by means of a structure based on the five-point strategy called DOTS, which has been adopted for TB control. However, it may be unrealistic to give TB control programmes the responsibility for running such a programme. A better approach might be to deliver highly active antiretroviral therapy within a comprehensive HIV/AIDS management strategy complementing the preventive work already being undertaken by AIDS control programmes. TB programmes could contribute towards the development and implementation of this strategy. PMID:12132003
Shu, Wen; Chen, Wei; Zhu, Shiyu; Hou, Yongchun; Mei, Jian; Bai, Liqiong; Xu, Weiguo; Zhou, Lin; Nie, Shaofa; Cheng, Shiming; Xu, Yihua
Few studies have examined, in a prospective cohort study, factors causing delay of access to tuberculosis (TB) diagnosis among new, active TB patients. A prospective cohort study (2009-2011) was carried out among 408 889 Chinese. Data on known/potential influencing factors were obtained from baseline questionnaires. We used stepwise logistic regression models to analyze the association between several known/potential influencing factors and diagnosis delay, assessed the current situation, and explored determinants of diagnosis delay. During follow-up and final visits, 202 new, active TB patients were found. Median patient delay was 5.4 (quartile 2.7-26) weeks, health system delay was 0 (quartile 0-1.6) weeks, and diagnosis delay was 9.9 (quartile 3.1-28.1) weeks. The influencing factors on patient delay were age and duration of symptoms. Smoking and sputum smear status were influencing factors for health system delay, and duration of symptoms was one of the factors for diagnosis delay. These findings provide information on the current situation of diagnosis delay and evidence for specific strategy development for TB control in China.
Prideaux, Brendan; Via, Laura E.; Zimmerman, Matthew D.; Eum, Seokyong; Sarathy, Jansy; O’Brien, Paul; Chen, Chao; Kaya, Firat; Weiner, Danielle M.; Chen, Pei-Yu; Song, Taeksun; Lee, Myungsun; Shim, TaeSun; Cho, Jeong Su; Kim, Wooshik; Cho, Sang Nae; Olivier, Kenneth N.; Barry, Clifton E.; Dartois, Véronique
Finding new treatment-shortening antibiotics to improve cure rates and curb the alarming emergence of drug resistance is the major objective of tuberculosis (TB) drug development. Using a MALDI mass spectrometry imaging suite in a biosafety containment facility, we show that the key sterilizing drugs rifampicin and pyrazinamide efficiently penetrate the sites of TB infection in lung lesions. Rifampicin even accumulates in necrotic caseum, a critical lesion site where persisting tubercle bacilli reside1. In contrast, moxifloxacin which is active in vitro against persisters, a sub-population of Mycobacterium tuberculosis that persists in specific niches under drug pressure, and achieved treatment shortening in mice2, does not diffuse well in caseum, concordant with its failure to shorten therapy in recent clinical trials. We also suggest that such differential spatial distribution and kinetics of accumulation in lesions may create temporal and spatial windows of monotherapy in specific niches, allowing the gradual development of multidrug resistant TB. We propose an alternative working model to prioritize new antibiotic regimens based on quantitative and spatial distribution of TB drugs in the major lesion types found in human lungs. The finding that lesion penetration contributes to treatment outcome has wide implications for TB. PMID:26343800
Multidrug-resistant tuberculosis (MDR-TB), the prevalence of which has increased across the globe in recent years, is a serious threat to public health. Timely diagnosis of MDR-TB, especially among new TB cases, is essential to facilitate appropriate treatment, which can prevent further emergence of drug resistance and its spread in the population. The present case report from India aims to address some operational challenges in diagnosing MDR-TB among new cases and potential measures to overcome them. It argues that even after seven years of implementing the DOTS-Plus program for controlling MDR-TB, India still lacks the technical capacity for rapid MDR-TB diagnosis. The case report underscores an urgent need to explore the use of WHO-endorsed techniques such as Xpert MTB/Rif and commercial assays such as Genotype MTBDR for rapid diagnosis of MDR-TB among new cases. Suitable applications may be found for other TB high-burden countries where MDR-TB is a major concern.
Bian, Zhong-Rui; Yin, Juan; Sun, Wen; Lin, Dian-Jie
Diagnose of active tuberculosis (TB) is challenging and treatment response is also difficult to efficiently monitor. The aim of this study was to use an integrated analysis of microarray and network-based method to the samples from publically available datasets to obtain a diagnostic module set and pathways in active TB. Towards this goal, background protein-protein interactions (PPI) network was generated based on global PPI information and gene expression data, following by identification of differential expression network (DEN) from the background PPI network. Then, ego genes were extracted according to the degree features in DEN. Next, module collection was conducted by ego gene expansion based on EgoNet algorithm. After that, differential expression of modules between active TB and controls was evaluated using random permutation test. Finally, biological significance of differential modules was detected by pathways enrichment analysis based on Reactome database, and Fisher's exact test was implemented to extract differential pathways for active TB. Totally, 47 ego genes and 47 candidate modules were identified from the DEN. By setting the cutoff-criteria of gene size >5 and classification accuracy ≥0.9, 7 ego modules (Module 4, Module 7, Module 9, Module 19, Module 25, Module 38 and Module 43) were extracted, and all of them had the statistical significance between active TB and controls. Then, Fisher's exact test was conducted to capture differential pathways for active TB. Interestingly, genes in Module 4, Module 25, Module 38, and Module 43 were enriched in the same pathway, formation of a pool of free 40S subunits. Significant pathway for Module 7 and Module 9 was eukaryotic translation termination, and for Module 19 was nonsense mediated decay enhanced by the exon junction complex (EJC). Accordingly, differential modules and pathways might be potential biomarkers for treating active TB, and provide valuable clues for better understanding of molecular
Tateosian, Nancy L; Pasquinelli, Virginia; Hernández Del Pino, Rodrigo E; Ambrosi, Nella; Guerrieri, Diego; Pedraza-Sánchez, Sigifredo; Santucci, Natalia; D'Attilio, Luciano; Pellegrini, Joaquín; Araujo-Solis, María A; Musella, Rosa M; Palmero, Domingo J; Hernandez-Pando, Rogelio; Garcia, Verónica E; Chuluyan, H Eduardo
Interferon (IFN)-γ displays a critical role in tuberculosis (TB), modulating the innate and adaptive immune responses. Previously, we reported that secretory leukocyte protease inhibitor (SLPI) is a pattern recognition receptor with anti-mycobacterial activity against Mycobacterium tuberculosis (Mtb). Herein, we determined whether IFN-γ modulated the levels of SLPI in TB patients. Plasma levels of SLPI and IFN-γ were studied in healthy donors (HDs) and TB patients. Peripheral blood mononuclear cells from HDs and patients with TB or defective IFN-γ receptor 1* were stimulated with Mtb antigen and SLPI, and IFN-γR expression levels were measured. Both SLPI and IFN-γ were significantly enhanced in plasma from those with TB compared with HDs. A direct association between SLPI levels and the severity of TB was detected. In addition, Mtb antigen stimulation decreased the SLPI produced by peripheral blood mononuclear cells from HDs, but not from TB or IFN-γR patients. Neutralization of IFN-γ reversed the inhibition of SLPI induced by Mtb antigen in HDs, but not in TB patients. Furthermore, recombinant IFN-γ was unable to modify the expression of SLPI in TB patients. Finally, IFN-γR expression was lower in TB compared with HD peripheral blood mononuclear cells. These results show that Mtb-induced IFN-γ down-modulated SLPI levels by signaling through the IFN-γR in HDs. This inhibitory mechanism was not observed in TB, probably because of the low expression of IFN-γR detected in these individuals.
Talbot, Elizabeth A.; Harland, Dawn; Wieland-Alter, Wendy; Burrer, Sherry; Adams, Lisa V.
Objective: Interferon-[gamma] release assays (IGRAs) are an important tool for detecting latent "Mycobacterium tuberculosis" infection (LTBI). Insufficient data exist about IGRA specificity in college health centers, most of which screen students for LTBI using the tuberculin skin test (TST). Participants: Students at a low-TB incidence college…
Rezai, Shadi; LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D; Henderson, Cassandra E
Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients.
LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D.; Henderson, Cassandra E.
Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients. PMID:26693374
den Boon, S; Verver, S; Lombard, C J; Bateman, E D; Irusen, E M; Enarson, D A; Borgdorff, M W; Beyers, N
Passive detection of tuberculosis (TB) cases may lead to delay in treatment which may contribute to increased severity of disease and mortality. Active case finding may be an alternative. In a community survey in Cape Town, South Africa, we actively detected 27 bacteriologically positive TB cases and compared those with 473 passively detected TB cases. Seven of 27 (26%) actively detected TB cases did not start treatment within 2 months and were considered initial defaulters. Those who did start treatment had similar treatment success rates as passively detected TB cases (both 80%) (OR 1.01, CI 0.33-3.09). Passively detected cases reported the presence of the symptoms cough (OR 3.72, 95% CI 1.47-9.39), haemoptysis (OR 3.20, 95% CI 1.03-9.93), night sweats (OR 3.35, 95% CI 1.40-7.99), fever (OR 4.28, 95% CI 1.21-15.14), and weight loss (OR 11.14, 95% CI 4.17-29.74) more often than those detected actively. We conclude that although TB cases detected by a community survey are less symptomatic and are prone to a high initial default rate, active case finding can potentially identify a substantial portion of the existing caseload at an earlier stage of disease, thereby reducing the risk of transmission.
Maeda, Hideo; Shirai, Chika
Japan is still "intermediate burden" country as medium-incidence of tuberculosis (TB). But the incidence of TB varies by public health units. The priority for TB control would be lowering in the areas where the incidence of TB is relatively low. In addition, younger age groups get low prevalence of TB infection than elderly persons. As a result, fewer experiences for TB diagnosis and treatment in the hospital and the medical facility would cause the delay in the detection of TB patients which eventually cause outbreaks. Although there are differences in population density and population mobility between urban and rural areas, the socially economic vulnerable patients and foreign patients are the common risks. Any public health units' policies of TB should correspond to the individual situation. At the era of low tuberculosis incidence, the infection risk is to be "From ubiquitous to the uneven distribution". This makes TB detection much more difficult. At this symposium, each speaker presented the case for actually experienced with QFT test and/or VNTR analysis. They mainly focused on the paradigm shift in TB control which is indispensable for resolving the gaps in regional differences and the differences in diagnostic capability. Although the cases in this symposium were not for the low incidence situation, the pioneering approaches presented here would boost the future application of QFT and VNTR analysis nationwide. The discussions also partially covered the technical infrastructure for molecular epidemiology which covers the whole country. By making full use of QFT test and VNTR analysis as a contact screening tool, we can appropriately understand the risk of TB infection in the region from a buildup of bacteria and patient information. Now is the time to prepare for. Active surveillance of TB by this way would clarify the risk of the disease and lead to the advocacy essential for the resolution. 1. Current situation and challenge of contact survey by using QFT
Korzeniewska, Anna; Dyła, Tomasz; Kosacka, Monika; Jankowska, Renata
Renal transplant recipients carry a relatively high risk of developing tuberculosis (TB). In most cases, active TB is the result of reactivation of a latent infection and is located in the lungs. In these patients, clinical presentation of TB can often be atypical and there is a high risk of dissemination and high mortality rates. Therefore, the use of invasive procedures for proper diagnosis is recommended, as well as anti-tuberculosis therapy instituted whenever there is a strong suspicion of TB on clinical grounds, even without microbiological evidence. The treatment of active TB in renal transplant recipients should be the same as in the general population. To avoid graft rejection, blood levels of calcineurin inhibitors should be monitored closely. Prophylaxis is recommended for high-risk patients.
Khanal, Sudeepa; Elsey, Helen; King, Rebecca; Baral, Sushil C; Bhatta, Bharat Raj; Newell, James N
Multi-drug-resistant tuberculosis (MDR-TB) poses a major threat to public health worldwide, particularly in low-income countries. The current long (20 month) and arduous treatment regime uses powerful drugs with side-effects that include mental ill-health. It has a high loss-to-follow-up (25%) and higher case fatality and lower cure-rates than those with drug sensitive tuberculosis (TB). While some national TB programmes provide small financial allowances to patients, other aspects of psychosocial ill-health, including iatrogenic ones, are not routinely assessed or addressed. We aimed to develop an intervention to improve psycho-social well-being for MDR-TB patients in Nepal. To do this we conducted qualitative work with MDR-TB patients, health professionals and the National TB programme (NTP) in Nepal. We conducted semi-structured interviews (SSIs) with 15 patients (10 men and 5 women, aged 21 to 68), four family members and three frontline health workers. In addition, three focus groups were held with MDR-TB patients and three with their family members. We conducted a series of meetings and workshops with key stakeholders to design the intervention, working closely with the NTP to enable government ownership. Our findings highlight the negative impacts of MDR-TB treatment on mental health, with greater impacts felt among those with limited social and financial support, predominantly married women. Michie et al's (2011) framework for behaviour change proved helpful in identifying corresponding practice- and policy-level changes. The findings from this study emphasise the need for tailored psycho-social support. Recent work on simple psychological support packages for the general population can usefully be adapted for use with people with MDR-TB.
Khanal, Sudeepa; Elsey, Helen; Baral, Sushil C.; Bhatta, Bharat Raj; Newell, James N.
Multi-drug-resistant tuberculosis (MDR-TB) poses a major threat to public health worldwide, particularly in low-income countries. The current long (20 month) and arduous treatment regime uses powerful drugs with side-effects that include mental ill-health. It has a high loss-to-follow-up (25%) and higher case fatality and lower cure-rates than those with drug sensitive tuberculosis (TB). While some national TB programmes provide small financial allowances to patients, other aspects of psychosocial ill-health, including iatrogenic ones, are not routinely assessed or addressed. We aimed to develop an intervention to improve psycho-social well-being for MDR-TB patients in Nepal. To do this we conducted qualitative work with MDR-TB patients, health professionals and the National TB programme (NTP) in Nepal. We conducted semi-structured interviews (SSIs) with 15 patients (10 men and 5 women, aged 21 to 68), four family members and three frontline health workers. In addition, three focus groups were held with MDR-TB patients and three with their family members. We conducted a series of meetings and workshops with key stakeholders to design the intervention, working closely with the NTP to enable government ownership. Our findings highlight the negative impacts of MDR-TB treatment on mental health, with greater impacts felt among those with limited social and financial support, predominantly married women. Michie et al’s (2011) framework for behaviour change proved helpful in identifying corresponding practice- and policy-level changes. The findings from this study emphasise the need for tailored psycho-social support. Recent work on simple psychological support packages for the general population can usefully be adapted for use with people with MDR-TB. PMID:28099475
Lounis, Nacer; Andries, Koen; Jarlier, Vincent
Rationale The sterilizing activity of the regimen used to treat multidrug resistant tuberculosis (MDR TB) has not been studied in a mouse model. Objective and Methods Swiss mice were intravenously inoculated with 6 log10 of Mycobacterium tuberculosis (TB) strain H37Rv, treated with second-line drug combinations with or without the diarylquinoline TMC207, and then followed without treatment for 3 more months to determine relapse rates (modified Cornell model). Measurements Bactericidal efficacy was assessed by quantitative lung colony-forming unit (CFU) counts. Sterilizing efficacy was assessed by measuring bacteriological relapse rates 3 months after the end of treatment. Main Results The relapse rate observed after 12 months treatment with the WHO recommended MDR TB regimen (amikacin, ethionamide, pyrazinamide and moxifloxacin) was equivalent to the relapse rate observed after 6 months treatment with the recommended drug susceptible TB regimen (rifampin, isoniazid and pyrazinamide). When TMC207 was added to this MDR TB regimen, the treatment duration needed to reach the same relapse rate dropped to 6 months. A similar relapse rate was also obtained with a 6-month completely oral regimen including TMC207, moxifloxacin and pyrazinamide but excluding both amikacin and ethionamide. Conclusions In this murine model the duration of the WHO MDR TB treatment could be reduced to 12 months instead of the recommended 18–24 months. The inclusion of TMC207 in the WHO MDR TB treatment regimen has the potential to further shorten the treatment duration and at the same time to simplify treatment by eliminating the need to include an injectable aminoglycoside. PMID:21408613
Shah, Maunank; Hanrahan, Colleen; Wang, Zhuo Yu; Dendukuri, Nandini; Lawn, Stephen D; Denkinger, Claudia M; Steingart, Karen R
Background Rapid detection of tuberculosis (TB) among people living with human immunodeficiency virus (HIV) is a global health priority. HIV-associated TB may have different clinical presentations and is challenging to diagnose. Conventional sputum tests have reduced sensitivity in HIV-positive individuals, who have higher rates of extrapulmonary TB compared with HIV-negative individuals. The lateral flow urine lipoarabinomannan assay (LF-LAM) is a new, commercially available point-of-care test that detects lipoarabinomannan (LAM), a lipopolysaccharide present in mycobacterial cell walls, in people with active TB disease. Objectives To assess the accuracy of LF-LAM for the diagnosis of active TB disease in HIV-positive adults who have signs and symptoms suggestive of TB (TB diagnosis).To assess the accuracy of LF-LAM as a screening test for active TB disease in HIV-positive adults irrespective of signs and symptoms suggestive of TB (TB screening). Search methods We searched the following databases without language restriction on 5 February 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE (PubMed,1966); EMBASE (OVID, from 1980); Science Citation Index Expanded (SCI-EXPANDED, from 1900), Conference Proceedings Citation Index-Science (CPCI-S, from 1900), and BIOSIS Previews (from 1926) (all three using the Web of Science platform; MEDION; LILACS (BIREME, from 1982); SCOPUS (from 1995); the metaRegister of Controlled Trials (mRCT); the search portal of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); and ProQuest Dissertations & Theses A&l (from 1861). Selection criteria Eligible study types included randomized controlled trials, cross-sectional studies, and cohort studies that determined LF-LAM accuracy for TB against a microbiological reference standard (culture or nucleic acid amplification test from any body site). A higher quality reference standard was one in which two or more specimen types were
Ben-Selma, Walid; Harizi, Hedi; Boukadida, Jalel
Monocyte chemoattractant protein-1 (MCP-1) plays crucial role in protective immunity against Mycobacterium tuberculosis (MT). In this study, we examined whether single nucleotide polymorphism (SNP) -2518 A/G (rs 1024611) of MCP-1 affect the susceptibility to active tuberculosis (TB) in Tunisian populations. Genomic DNA from patients with active TB (168 cases of pulmonary TB and 55 cases of extrapulmonary TB) and ethnically controls (150 cases) was genotyped for the MCP-1 -2518 A/G SNP by polymerase chain reaction fragment length polymorphism (PCR-RFLP). We observed that -2518 G allele and GG genotype (high MCP-1 producer) frequencies were significantly more elevated in active pulmonary TB group in comparison to control group [34 vs. 22%; P = 0.0007; 15 vs. 5%, P corrected for the number of genotypes (Pc) = 0.015; respectively]. Additionally, they were associated with increased risk development of this clinical form of TB [odds ratio (OR) = 1.83, 95% confidence intervals (CI) = 1.26-2.66; OR = 3.1, 95% CI = 1.28-7.76; respectively]. However, wild type allele -2518 A and AA genotype were over-represented in control group (78 and 62%) and seem to be protective factors against TB. Moreover, -2518 AA genotype was more frequent in control group and was associated with resistance against development of active pulmonary TB (OR = 0.56, 95% CI = 0.35-0.89, Pc = 0.03). Our findings confirm the key role of -2518 A/G SNP of MCP-1 and support its association with resistance/susceptibility to the development of active pulmonary TB in the Tunisian population.
Michel, A L; Hlokwe, T M; Espie, I W; van Zijll Langhout, M; Koeppel, K; Lane, E
This study reports on an investigation of Mycobacterium tuberculosis cases in mostly captive wild animals using molecular typing tools [Variable Number of Tandem Repeat (VNTR) typing and Restriction Fragment Length Polymorphism typing]. The investigation included cases from (i) the National Zoological Gardens of South Africa (NZG) recorded between 2002 and 2011; (ii) Johannesburg Zoo, where tuberculosis was first diagnosed in 2007 and has since been detected in three antelope species; (iii) a rehabilitation centre for vervet monkeys (Chlorocebus pygerythrus) in which M. tuberculosis was diagnosed in 2008; and (iv) incidental cases in other facilities including a sable antelope (Hippotragus niger), two unrelated cases in chacma baboons (Papio ursinus) (one of which was from a free-ranging troop) and a colony of capuchin monkeys (Cebus capucinus). Identical genetic profiles of the latter three isolates indicate the persistence of a single M. tuberculosis strain in this population since at least 2006. Results of the outbreak investigation in the captive vervet monkey colony indicate that it was caused by two unrelated strains, while all 13 M. tuberculosis isolates from 11 animal species in the NZG showed different VNTR patterns. A substantial increase in tuberculosis cases of 60% was recorded in the NZG, compared with the previous reporting period 1991-2001, and may indicate a countrywide trend of increasing spillover of human tuberculosis to wild animals. South Africa ranks among the countries with the highest-tuberculosis burden worldwide, complicated by an increasing rate of multidrug-resistant strains. Exposure and infection of captive wildlife in this high prevalence setting is therefore a growing concern for wildlife conservation but also for human health through potential spillback.
Linguissi, Laure Stella Ghoma; Gwom, Luc Christian; Nkenfou, Celine Nguefeu; Bates, Matthew; Petersen, Eskild; Zumla, Alimuddin; Ntoumi, Francine
The Republic of Congo is on the World Health Organization (WHO) list of 'high burden' countries for tuberculosis (TB) and HIV. TB is the leading cause of death among HIV-infected patients in the Republic of Congo. In this viewpoint, the available data on TB and HIV in the Republic of Congo are reviewed, and the gaps and bottlenecks that the National TB Control Program (NTCP) faces are discussed. Furthermore, priority requirements for developing and implementing TB and HIV collaborative service activities are identified. HIV and TB control programs operate as distinct entities with separate case management plans. The implementation of collaborative TB/HIV activities to evaluate and monitor the management of TB/HIV co-infected individuals remains inefficient in most regions, and these activities are sometimes non-existent. This reveals major challenges that require definition in order to improve the delivery of healthcare. The NTCP lacks adequate resources for optimal implementation of control measures of TB and HIV compliance and outcomes. The importance of aligning and integrating TB and HIV treatment services (including follow-up) and adherence support services through coordinated and collaborative efforts between individual TB and HIV programs is discussed. Aligning and integrating TB and HIV treatment services through coordinated and collaborative efforts between individual TB and HIV programs is required. However, the WHO recommendations are generic, and health services in the Republic of Congo need to tailor their TB and HIV programs according to the availability of resources and operational feasibility. This will also open opportunities for synergizing collaborative TB/HIV research and training activities, which should be prioritized by the donors supporting the TB/HIV programs.
Basile, J I; Kviatcovsky, D; Romero, M M; Balboa, L; Monteserin, J; Ritacco, V; Lopez, B; Sabio y García, C; García, A; Vescovo, M; Montaner, P G; Palmero, D; Del Carmen Sasiain, M; de la Barrera, S
We have reported previously that T cells from patients with multi-drug-resistant tuberculosis (MDR-TB) express high levels of interleukin (IL)-17 in response to the MDR strain M (Haarlem family) of Mycobacterium tuberculosis (M. tuberculosis). Herein, we explore the pathways involved in the induction of Th17 cells in MDR-TB patients and healthy tuberculin reactors [purified protein derivative healthy donors (PPD(+) HD)] by the M strain and the laboratory strain H37Rv. Our results show that IL-1β and IL-6 are crucial for the H37Rv and M-induced expansion of IL-17(+) interferon (IFN)-γ(-) and IL-17(+) IFN-γ(+) in CD4(+) T cells from MDR-TB and PPD(+) HD. IL-23 plays an ambiguous role in T helper type 1 (Th1) and Th17 profiles: alone, IL-23 is responsible for M. tuberculosis-induced IL-17 and IFN-γ expression in CD4(+) T cells from PPD(+) HD whereas, together with transforming growth factor (TGF-β), it promotes IL-17(+) IFN-γ(-) expansion in MDR-TB. In fact, spontaneous and M. tuberculosis-induced TGF-β secretion is increased in cells from MDR-TB, the M strain being the highest inducer. Interestingly, Toll-like receptor (TLR)-2 signalling mediates the expansion of IL-17(+) IFN-γ(-) cells and the enhancement of latency-associated protein (LAP) expression in CD14(+) and CD4(+) T cells from MDR-TB, which suggests that the M strain promotes IL-17(+) IFN-γ(-) T cells through a strong TLR-2-dependent TGF-β production by antigen-presenting cells and CD4(+) T cells. Finally, CD4(+) T cells from MDR-TB patients infected with MDR Haarlem strains show higher IL-17(+) IFN-γ(-) and lower IL-17(+) IFN-γ(+) levels than LAM-infected patients. The present findings deepen our understanding of the role of IL-17 in MDR-TB and highlight the influence of the genetic background of the infecting M. tuberculosis strain on the ex-vivo Th17 response.
Mpagama, Stellah G; Ndusilo, Norah; Stroup, Suzanne; Kumburu, Happiness; Peloquin, Charles A; Gratz, Jean; Houpt, Eric R; Kibiki, Gibson S; Heysell, Scott K
Little is known about plasma drug concentrations relative to quantitative susceptibility in patients with multidrug-resistant tuberculosis (MDR-TB). We previously described a TB drug activity (TDA) assay that determines the ratio of the time to detection of plasma-cocultured Mycobacterium tuberculosis versus control growth in a Bactec MGIT system. Here, we assess the activity of individual drugs in a typical MDR-TB regimen using the TDA assay. We also examined the relationship of the TDA to the drug concentration at 2 h (C2) and the MICs among adults on a MDR-TB regimen in Tanzania. These parameters were also compared to the treatment outcome of sputum culture conversion. Individually, moxifloxacin yielded superior TDA results versus ofloxacin, and only moxifloxacin and amikacin yielded TDAs equivalent to a -2-log killing. In the 25 patients enrolled on a regimen of kanamycin, levofloxacin, ethionamide, pyrazinamide, and cycloserine, the C2 values were found to be below the expected range for levofloxacin in 13 (52%) and kanamycin in 10 (40%). Three subjects with the lowest TDA result (<1.5, a finding indicative of poor killing) had significantly lower kanamycin C2/MIC ratios than subjects with a TDA of ≥1.5 (9.8 ± 8.7 versus 27.0 ± 19.1; P = 0.04). The mean TDAs were 2.52 ± 0.76 in subjects converting to negative in ≤2 months and 1.88 ± 0.57 in subjects converting to negative in >2 months (P = 0.08). In Tanzania, MDR-TB drug concentrations were frequently low, and a wide concentration/MIC range was observed that affected plasma drug activity ex vivo. An opportunity exists for pharmacokinetic optimization in current MDR-TB regimens, which may improve treatment response.
Shankar, Esaki M; Velu, Vijayakumar; Kamarulzaman, Adeeba; Larsson, Marie
Immunosenescence is marked by accelerated degradation of host immune responses leading to the onset of opportunistic infections, where senescent T cells show remarkably higher ontogenic defects as compared to healthy T cells. The mechanistic association between T-cell immunosenescence and human immunodeficiency virus (HIV) disease progression, and functional T-cell responses in HIV-tuberculosis (HIV-TB) co-infection remains to be elaborately discussed. Here, we discussed the association of immunosenescence and chronic immune activation in HIV-TB co-infection and reviewed the role played by mediators of immune deterioration in HIV-TB co-infection necessitating the importance of designing therapeutic strategies against HIV disease progression and pathogenesis. PMID:25674514
Tuberculosis (TB) continues as a major public health challenge worldwide. HIV-TB coinfection is especially concerning as it accelerates progression of infection to active disease and amplifies spread of TB including drug resistant disease. Application of molecular biology and insights from classic microbiology to TB control have resulted in important innovations in diagnosis and treatment. Radiometric assay and, particularly, PCR, with nucleic acid probing, have reduced the time to diagnosis. Moreover, the sensitivity of these techniques is potentially log orders of magnitude more sensitive. Molecular techniques can be adapted to drug susceptibility testing. The differential activity and post-antibiotic effect of various drugs against TB have led to highly effective briefer regimens and to directly observed therapy. Insights into basic host defense against TB and description of the M. tuberculosis genome have created optimism for developing new treatments and effective vaccines in the years to come. PMID:16555622
Ghosh, Smita; Moonan, Patrick K; Cowan, Lauren; Grant, Juliana; Kammerer, Steve; Navin, Thomas R
Molecular characterization of Mycobacterium tuberculosis complex isolates (genotyping) can be used by public health programs to more readily identify tuberculosis (TB) transmission. The Centers for Disease Control and Prevention's National Tuberculosis Genotyping Service has offered M. tuberculosis genotyping for every culture-confirmed case in the United States since 2004. The TB Genotyping Information Management System (TB GIMS), launched in March 2010, is a secure online database containing genotype results linked with case characteristics from the national TB registry for state and local TB programs to access, manage and analyze these data. As of September 2011, TB GIMS contains genotype results for 89% of all culture-positive TB cases for 2010. Over 400 users can generate local and national reports and maps using TB GIMS. Automated alerts on geospatially concentrated cases with matching genotypes that may represent outbreaks are also generated by TB GIMS. TB genotyping results are available to enhance national TB surveillance and apply genotyping results to conduct TB control activities in the United States.
Contribution of Interferon gamma release assays testing to the diagnosis of latent tuberculosis infection in HIV-infected patients: A comparison of QuantiFERON-TB Gold In Tube, T-SPOT.TB and tuberculin skin test
Background Diagnosis and treatment of latent tuberculosis infection (LTBI) is the most effective strategy to control tuberculosis (TB) among patients with HIV infection. The tuberculin skin test (TST) was the only available method to identify LTBI. The aim of the present work was to evaluate the usefulness of the interferon-gamma release assays (IGRAs): QuantiFERON-tuberculosis (TB) Gold-In-Tube test (QFG) and T-SPOT.TB for the diagnosis of LTBI in a diverse cohort of HIV-infected patients. Methods A prospective study was carried out in consecutive patients cared for in a single institution in Spain from January 2009 to October 2010. IGRAs and TST were performed simultaneously. TST induration ≥ 5 mm was considered positive. Results QFG, T-SPOT.TB and TST were performed in 373 subjects. Median CD4 cell count was 470/μl with a median nadir of 150/μl. TST, QFG and T-SPOT.TB were positive in 13.3%, 7.5% and 18.5% cases respectively. Among 277 patients with neither past or current TB nor previous treatment for LTBI and who had TST results, a positive TST result was obtained in 20 (7.2%) cases. When adding QFG results to TST, there were a total of 26 (8.6%) diagnoses of LTBI. When the results of both IGRAs were added, the number of diagnoses increased to 54 (17.9%) (incremental difference: 10.7% [95% confidence interval [CI]:5.3-16.2%] [p < 0.001]), and when both IGRAs were added, the number of diagnoses reached 56 (18.5%) (incremental difference: 11.3% [95% CI:5.7%–16.9%] [p < 0.001]). Patients with a CD4 cell count greater than 500 cells/μl and prior stay in prison were more likely to have a diagnosis of LTBI by TST and/or QFG and/or T-SPOT.TB (adjusted odds ratio [aOR]: 3.8; 95% CI, 1.4 – 9.9; and aOR: 3.3; 95% CI, 1.3 – 8.3, respectively). Conclusions IGRAs were more sensitive than TST for diagnosis of M. tuberculosis infection in HIV-infected patients. Dual sequential testing with TST and IGRAs may be the optimal approach for LTBI screening in this
Ben-selma, Walid; Harizi, Hedi; Marzouk, Manel; Ben Kahla, Imen; Ben Lazreg, Foued; Ferjeni, Asma; Boukadida, Jalel
The purpose of the present study was to evaluate the clinical usefulness of detection of serum immunoglobulin A (IgA), IgG, and IgM antibodies raised against the mycobacterial A60 antigen for the diagnosis and discrimination of active tuberculosis (TB) from other pulmonary diseases. Three commercially available ELISA kits (IgA, IgG, and IgM) (ANDA Biologicals, Strasbourg, France) were evaluated simultaneously in 246 serum samples from 3 groups of patients: group I, 171 patients with active TB (128 pulmonary TB and 43 extrapulmonary TB); group II, 73 patients with pulmonary non-TB diseases; and group III, 2 leprosies patients. The sensitivities of tests ranged from 31.3% (IgA) to 94% (IgG) in pulmonary TB patients and from 21% (IgA) to 84% (IgG) in extrapulmonary TB patients. The specificities of assays varied from 92% (IgG) to 96% (IgA) in the pulmonary non-TB group. Combination of IgG with IgA and/or IgM does not improve its sensitivity. Clinical use of the A60-based serodiagnostic IgG assay is of great value for the rapid diagnosis and discrimination between active TB and pulmonary non-TB diseases. Moreover, this test could be used to increase diagnostic accuracy, especially for smear-negative TB cases, which are difficult to diagnose.
... org > Lung Health and Diseases > Lung Disease Lookup > Tuberculosis (TB) What Is Multidrug and Extensively Drug Resistant TB? Multidrug-resistant tuberculosis ( MDR TB ) is a very dangerous form of ...
... component to TB elimination in the United States. Tuberculosis (TB) is a disease caused by bacteria that ... is essential to these efforts. More Information Reported Tuberculosis in the United States, 2012 TB in Correctional ...
Williams, Ann; Hatch, Graham J; Clark, Simon O; Gooch, Karen E; Hatch, Kim A; Hall, Graham A; Huygen, Kris; Ottenhoff, Tom H M; Franken, Kees L M C; Andersen, Peter; Doherty, T Mark; Kaufmann, Stefan H E; Grode, Leander; Seiler, Peter; Martin, Carlos; Gicquel, Brigitte; Cole, Stewart T; Brodin, Priscille; Pym, Alexander S; Dalemans, Wilfried; Cohen, Joe; Lobet, Yves; Goonetilleke, Nilu; McShane, Helen; Hill, Adrian; Parish, Tanya; Smith, Debbie; Stoker, Neil G; Lowrie, Douglas B; Källenius, Gunilla; Svenson, Stefan; Pawlowski, Andrzej; Blake, Karen; Marsh, Philip D
The TB Vaccine Cluster project funded by the EU Fifth Framework programme aims to provide novel vaccines against tuberculosis that are suitable for evaluation in humans. This paper describes the studies of the protective efficacy of vaccines in a guinea pig aerosol-infection model of primary tuberculosis. The objective was to conduct comparative evaluations of vaccines that had previously demonstrated efficacy in other animal models. Groups of 6 guinea pigs were immunized with vaccines provided by the relevant EU Vaccine Cluster partners. Survival over 17 or 26 weeks was used as the principal measure of vaccine efficacy following aerosol challenge with H37Rv. Counts of mycobacteria in lungs and spleens, and histopathological changes in the lungs, were also used to provide evidence of protection. A total of 24 vaccines were evaluated in 4 experiments each of a different design. A heterologous prime-boost strategy of DNA and MVA, each expressing Ag85A and a fusion protein of ESAT-6 and Ag85B in adjuvant, protected the guinea pigs to the same extent as BCG. Genetically modified BCG vaccines and boosted BCG strategies also protected guinea pigs to the same extent as BCG but not statistically significantly better. A relatively high aerosol-challenge dose and evaluation over a protracted time post-challenge allowed superior protection over BCG to be demonstrated by BCG boosted with MVA and fowl pox vectors expressing Ag85A.
Wang, Feng; Hou, Hongyan; Wu, Shiji; Tang, Qing; Huang, Min; Yin, Botao; Huang, Jing; Liu, Weiyong; Mao, Lie; Lu, Yanfang; Sun, Ziyong
Active tuberculosis (TB) patients show impaired NK cell function, and the underlying mechanism remains largely unknown. In this study, we confirmed the decrease in activation, cytokine secretion, and degranulation potential of NK cells in active TB patients. We further investigated whether coinhibitory receptor Tim-3 was involved with impairment of NK cells. Our results revealed that the expression of Tim-3 on NK cells was increased in active TB patients. Tim-3 expression was inversely correlated with IL-12-stimualted IFN-γ production. Moreover, blocking the Tim-3 pathway restored IFN-γ secretion and degranulation of NK cells. Blocking this pathway also increased NK cell cytotoxicity against K562 target cells, and improved the ability of NK cells to control Mtb growth in monocyte-derived macrophages. The Tim-3 expression on NK cells was also observed to be significantly decreased in TB patients post-treatment. In this study, we have identified that Tim-3 is involved with NK cell impairment in TB patients.
Systematic review on tuberculosis transmission on aircraft and update of the European Centre for Disease Prevention and Control risk assessment guidelines for tuberculosis transmitted on aircraft (RAGIDA-TB).
Kotila, Saara M; Payne Hallström, Lara; Jansen, Niesje; Helbling, Peter; Abubakar, Ibrahim
As a setting for potential tuberculosis (TB) transmission and contact tracing, aircraft pose specific challenges. Evidence-based guidelines are needed to support the related-risk assessment and contact-tracing efforts. In this study evidence of TB transmission on aircraft was identified to update the Risk Assessment Guidelines for TB Transmitted on Aircraft (RAGIDA-TB) of the European Centre for Disease Prevention and Control (ECDC). Electronic searches were undertaken from Medline (Pubmed), Embase and Cochrane Library until 19 July 2013. Eligible records were identified by a two-stage screening process and data on flight and index case characteristics as well as contact tracing strategies extracted. The systematic literature review retrieved 21 records. Ten of these records were available only after the previous version of the RAGIDA guidelines (2009) and World Health Organization guidelines on TB and air travel (2008) were published. Seven of the 21 records presented some evidence of possible in-flight transmission, but only one record provided substantial evidence of TB transmission on an aircraft. The data indicate that overall risk of TB transmission on aircraft is very low. The updated ECDC guidelines for TB transmission on aircraft have global implications due to inevitable need for international collaboration in contract tracing and risk assessment.
Kaufmann, Stefan H E; Parida, Shreemanta K
In Africa, more than 4 million people suffer from active tuberculosis (TB) resulting in an estimated 650,000 deaths every year. The etiologic agent of TB, Mycobacterium tuberculosis, survives in resting macrophages, which control the pathogen after activation by specific T lymphocytes. Here, we describe the basic mechanisms underlying the host response to TB with an emphasis on immunity and discuss diagnostics, drugs, and vaccines for TB. Moreover, we outline our attempts to develop biomarkers, which could help the monitoring of TB clinical trials, provide the basis for new diagnostics, and allow prognosis of outcome of infection and of drug treatment.
Rangkuti, Yulita M.; Sinaga, Marlina S.; Marpaung, F.; Side, Syafruddin
In this work, Vaccination (V), Susceptible (S) Infected (I), and Recovered (R) (VSIR) model for transmission of Tuberculosis in North Sumatera is modified. An exposed class is adopted to VSIR model so called VSEIR to determine the probability of people who infectious before infected. This model is written in ordinary differential equation (ODEs) in five classes. Determination the equilibrium point and stability analysis of the model is discussed to determine the dynamic behaviour of systems. A simulation is also discussed to see the suitable model to North Sumatera data. The simulation of VSEIR model indicates Tuberculosis has not endemic in North Sumatera.
Zheng, Chunlan; Hu, Minhui; Gao, Feng
ABSTRACT Background: The double burden of tuberculosis (TB) and diabetes mellitus (DM) is hitting certain Asian countries harder than other areas. In a global estimate, 15% of all TB cases could be attributable to DM, with 40% of those cases coming from India and China. Many other countries of South, East, and South-East Asia are of particular concern given their TB burdens, large projected increases in DM prevalence, and population size. Objective: In this narrative review, we aimed to: (i) give an overall insight into the evidence on TB-DM epidemiology from high double burden Asian countries, (ii) present the evidence on bi-directional screening implementation in this region, (iii) discuss possible factors related to higher TB susceptibility of Asian diabetic patients, and (iv) identify TB-DM comorbidity treatment challenges. Methods: The PubMed and Google Scholar databases were searched for all studies addressing DM/TB epidemiology, bi-directional screening and management in South, East and South-East Asia. Results: We identified the DM prevalences among TB patients as ranging from approximately 5% to more than 50%, whereas TB prevalences among diabetic patients were 1.8–9.5 times higher than in the general population in developing Asian countries. Evidence from studies designed to address diagnosis and treatment of the dual disease in these critical regions is scarce as well as the evidence related to possible DM patients’ genetic and acquired predisposition for TB. Conclusion: More prospective studies specifically designed to address adequate screening techniques, identify patients at risk, and define an adequate treatment of dual disease in this region are needed without delay. PMID:28245710
OBJECTIVES: The tuberculin skin test (TST) and the QuantiFERON-TB Gold test (QFT) are used to identify latent tuberculosis infections (LTBIs). The aim of this study was to determine the agreement between these two tests among health care workers in Iran. METHODS: This cross-sectional study included 177 tuberculosis (TB) laboratory staff and 67 non-TB staff. TST indurations of 10 mm or more were considered positive. The Student’s t-test and the chi-square test were used to compare the mean score and proportion of variables between the TB laboratory staff and the non-TB laboratory staff. Kappa statistics were used to evaluate the agreement between these tests, and logistic regression was used to assess the risk factors associated with positive results for each test. RESULTS: The prevalence of LTBIs according to both the QFT and the TST was 17% (95% confidence interval [CI], 12% to 21%) and 16% (95% CI, 11% to 21%), respectively. The agreement between the QFT and the TST was 77.46%, with a kappa of 0.19 (95% CI, 0.04 to 0.34). CONCLUSIONS: Although the prevalence of LTBI based on the QFT and the TST was not significantly different, the kappa statistic was low between these two tests for the detection of LTBIs. PMID:27457062
Khamis, Faryal; Al-Lawati, Adil; Al-Zakwani, Ibrahim; Al-Abri, Seif; Al-Naamani, Jaleelah; Al-Harthi, Harith; Al-Jardani, Amina; Al-Harthi, Aliya
Objectives Data on the prevalence of tuberculosis (TB) in healthcare workers (HCW) in Oman and the Arabian Gulf is scarce. The aim of this study was to estimate the prevalence of latent tuberculosis (LTB) among HCW exposed to active TB in one of the tertiary care hospitals in Muscat. Methods Exposed HCW were screened for LTB from January to June 2012 using skin tuberculin and serum interferon tests. Candidates were followed-up for a total of nine months. Descriptive statistics were used to summarize the data. Results A total of 371 exposed HCW were involved in the study. The incidence of LTB in exposed HCW was 33.2% (n = 123). Almost 54% (66/123) of the HCW started treatment and only 42.4% (28/66) completed the full nine-month treatment course. Conclusions The high prevalence of LTBI in exposed HCW merits further evaluation of the screening and treatment programs in the country. Future countrywide studies are warranted to provide more precise statistics on the prevalence and management of this public health issue. PMID:27403243
Shang, H; Desgrandchamps, D
In Switzerland, in 1992, 957 persons suffered from tuberculosis; 52.3% were Swiss, 47.7% foreigners. Most of the swiss TB patients were more than 65 years old, whereas the foreigners generally were young patients originating from countries with high TB-infection rates. Asylum seekers had much higher TB-case rates (131 cases per 100,000) than other foreigners (27 cases per 100,000) or Swiss (9 cases per 100,000). Special refuge reception centers have been set up in Switzerland, in charge of tuberculosis screening procedures in this high-risk group on arrival to this country. Although HIV and AIDS patients bear a much higher risk of developing tuberculosis once infected, the HIV epidemic did not lead to an increase of tuberculosis in Switzerland so far, since young Swiss are rarely infected with tuberculosis. HIV-infected, drug addicts, homeless persons and alcoholics run a higher risk of contracting tuberculosis only when congregating with a person suffering from active tuberculosis not yet diagnosed or improperly treated. In order to maintain low levels of tuberculosis in Switzerland DOT (directly observed therapy) must be implemented in all patients with uncertain compliance, especially as cultural and social backgrounds become increasingly complex.
Dutta, Noton K; Illei, Peter B; Peloquin, Charles A; Pinn, Michael L; Mdluli, Khisimuzi E; Nuermberger, Eric L; Grosset, Jacques H; Karakousis, Petros C
Rifamycins are key sterilizing drugs in the current treatment of active tuberculosis (TB). Daily dosing of rifapentine (P), a potent rifamycin with high intracellular accumulation, in place of rifampin (R) in the standard antitubercular regimen significantly shortens the duration of treatment needed to prevent relapse in a murine model of active TB. We undertook the current study to compare directly the activities of human-equivalent doses of P and R in a guinea pig model of chronic TB, in which bacilli are predominantly extracellular within human-like necrotic granulomas. Hartley strain guinea pigs were aerosol infected with ~200 bacilli of Mycobacterium tuberculosis H37Rv, and treatment given 5 days/week was initiated 6 weeks later. R at 100 mg/kg of body weight and P at 100 mg/kg were given orally alone or in combination with isoniazid (H) at 60 mg/kg and pyrazinamide (Z) at 300 mg/kg. Culture-positive relapse was assessed in subgroups of guinea pigs after completion of 1 and 2 months of treatment. Human-equivalent doses of R and P showed equivalent bactericidal activity when used alone and in combination therapy. In guinea pigs treated with rifampin, isoniazid, and pyrazinamide (RHZ) or PHZ, microbiological relapse occurred in the lungs of 8/10 animals treated for 1 month and in 0/10 animals treated for 2 months. Substitution of P for R in the standard antitubercular regimen did not shorten the time to cure in this guinea pig model of chronic TB. Data from ongoing clinical trials comparing the activity of these two drugs are awaited to determine the relevance of the guinea pig TB model in preclinical drug screening.
Dutta, Noton K.; Illei, Peter B.; Peloquin, Charles A.; Pinn, Michael L.; Mdluli, Khisimuzi E.; Nuermberger, Eric L.; Grosset, Jacques H.
Rifamycins are key sterilizing drugs in the current treatment of active tuberculosis (TB). Daily dosing of rifapentine (P), a potent rifamycin with high intracellular accumulation, in place of rifampin (R) in the standard antitubercular regimen significantly shortens the duration of treatment needed to prevent relapse in a murine model of active TB. We undertook the current study to compare directly the activities of human-equivalent doses of P and R in a guinea pig model of chronic TB, in which bacilli are predominantly extracellular within human-like necrotic granulomas. Hartley strain guinea pigs were aerosol infected with ∼200 bacilli of Mycobacterium tuberculosis H37Rv, and treatment given 5 days/week was initiated 6 weeks later. R at 100 mg/kg of body weight and P at 100 mg/kg were given orally alone or in combination with isoniazid (H) at 60 mg/kg and pyrazinamide (Z) at 300 mg/kg. Culture-positive relapse was assessed in subgroups of guinea pigs after completion of 1 and 2 months of treatment. Human-equivalent doses of R and P showed equivalent bactericidal activity when used alone and in combination therapy. In guinea pigs treated with rifampin, isoniazid, and pyrazinamide (RHZ) or PHZ, microbiological relapse occurred in the lungs of 8/10 animals treated for 1 month and in 0/10 animals treated for 2 months. Substitution of P for R in the standard antitubercular regimen did not shorten the time to cure in this guinea pig model of chronic TB. Data from ongoing clinical trials comparing the activity of these two drugs are awaited to determine the relevance of the guinea pig TB model in preclinical drug screening. PMID:22547623
Sweilam, Nasser H; Al-Mekhlafi, Seham M
In this paper, we presented a novel multi-strain TB model of variable-order fractional derivatives, which incorporates three strains: drug-sensitive, emerging multi-drug resistant (MDR) and extensively drug-resistant (XDR), as an extension for multi-strain TB model of nonlinear ordinary differential equations which developed in 2014 by Arino and Soliman . Numerical simulations for this variable-order fractional model are the main aim of this work, where the variable-order fractional derivative is defined in the sense of Grünwald-Letnikov definition. Two numerical methods are presented for this model, the standard finite difference method (SFDM) and nonstandard finite difference method (NSFDM). Numerical comparison between SFDM and NSFDM is presented. It is concluded that, NSFDM preserves the positivity of the solutions and numerically stable in large regions than SFDM.
Sweilam, Nasser H.; AL-Mekhlafi, Seham M.
In this paper, we presented a novel multi-strain TB model of variable-order fractional derivatives, which incorporates three strains: drug-sensitive, emerging multi-drug resistant (MDR) and extensively drug-resistant (XDR), as an extension for multi-strain TB model of nonlinear ordinary differential equations which developed in 2014 by Arino and Soliman . Numerical simulations for this variable-order fractional model are the main aim of this work, where the variable-order fractional derivative is defined in the sense of Grünwald–Letnikov definition. Two numerical methods are presented for this model, the standard finite difference method (SFDM) and nonstandard finite difference method (NSFDM). Numerical comparison between SFDM and NSFDM is presented. It is concluded that, NSFDM preserves the positivity of the solutions and numerically stable in large regions than SFDM. PMID:26966568
Malotte, C K; Rhodes, F; Mais, K E
OBJECTIVES: This study assessed the independent and combined effects of different levels of monetary incentives and a theory-based educational intervention on return for tuberculosis (TB) skin test reading in a sample of active injection drug and crack cocaine users. Prevalence of TB infection in this sample was also determined. METHODS: Active or recent drug users (n = 1004), recruited via street outreach techniques, were skin tested for TB. They were randomly assigned to 1 of 2 levels of monetary incentive ($5 and $10) provided at return for skin test reading, alone or in combination with a brief motivational education session. RESULTS: More than 90% of those who received $10 returned for skin test reading, in comparison with 85% of those who received $5 and 33% of those who received no monetary incentive. The education session had no impact on return for skin test reading. The prevalence of a positive tuberculin test was 18.3%. CONCLUSIONS: Monetary incentives dramatically increase the return rate for TB skin test reading among drug users who are at high risk of TB infection. PMID:9585747
Kim, Ji Han; Yim, Jae-Joon
After the Korean War (1950-1953), nearly 6.5% of South Korea's population had active tuberculosis (TB). In response, South Korea implemented the National Tuberculosis Program in 1962. From 1965 to 1995, the prevalence of bacteriologically confirmed pulmonary TB in South Korea decreased from 940 to 219 cases per 100,000 population. Astounding economic growth might have contributed to this result; however, TB incidence in South Korea remains the highest among high-income countries. The rate of decrease in TB incidence seems to have slowed over the past 15 years. A demographic shift toward an older population, many of whom have latent TB and various concurrent conditions, is challenging TB control efforts in South Korea. The increasing number of immigrants also plays a part in the prolonged battle against TB. A historical review of TB in South Korea provides an opportunity to understand national TB control efforts that are applicable to other parts of the world.
Campo, M; Shrestha, A; Oren, E; Thiede, H; Duchin, J; Narita, M; Crothers, K
The impact of hepatitis C virus infection (HCI), the most common bloodborne virus infection in the USA, on outcome of active tuberculosis (TB) treatment is largely unknown. We aimed to describe characteristics of TB patients with hepatitis C virus infection (TB-HCI) in King County, Washington, including TB treatment duration and outcome. We reviewed 1510 records of patients treated for active TB at the Public Health - Seattle & King County Tuberculosis Control Program between 2000 and 2010, and identified 53 with HCI. Advanced age, being born in the USA, HIV infection, homelessness and injection drug use were independently associated with HCI in TB cases. Independent factors associated with increased treatment duration included HIV infection, excess alcohol use, extrapulmonary TB, and any drug-resistant TB disease. Our findings suggest that TB-HCI patients can be successfully treated for active TB without extending treatment duration.
Pollock, Katrina M.; Whitworth, Hilary S.; Montamat-Sicotte, Damien J.; Grass, Lisa; Cooke, Graham S.; Kapembwa, Moses S.; Kon, Onn M.; Sampson, Robert D.; Taylor, Graham P.; Lalvani, Ajit
Background. Changes in the phenotype and function of Mycobacterium tuberculosis (M. tuberculosis)-specific CD4+ and CD8+ T-cell subsets in response to stage of infection may allow discrimination between active tuberculosis and latent tuberculosis infection. Methods. A prospective comparison of M. tuberculosis-specific cellular immunity in subjects with active tuberculosis and latent tuberculosis infection, with and without human immunodeficiency virus (HIV) coinfection. Polychromatic flow cytometry was used to measure CD4+ and CD8+ T-cell subset phenotype and secretion of interferon γ (IFN-γ), interleukin 2 (IL-2), and tumor necrosis factor α (TNF-α). Results. Frequencies of CD4+ and CD8+ cells secreting IFN-γ-only, TNF-α-only and dual IFN-γ/TNF-α were greater in active tuberculosis vs latent tuberculosis infection. All M. tuberculosis-specific CD4+ subsets, with the exception of IL-2-only cells, switched from central to effector memory phenotype in active tuberculosis vs latent tuberculosis infection, accompanied by a reduction in IL-7 receptor α (CD127) expression. The frequency of PPD-specific CD4+ TNF-α-only-secreting T cells with an effector phenotype accurately distinguished active tuberculosis from latent tuberculosis infection with an area under the curve of 0.99, substantially more discriminatory than measurement of function alone. Conclusions. Combined measurement of T-cell phenotype and function defines a highly discriminatory biomarker of tuberculosis disease activity. Unlocking the diagnostic and monitoring potential of this combined approach now requires validation in large-scale prospective studies. PMID:23966657
Sun, Ying; Weng, Yan; Zhang, Ying; Yan, Xiang; Guo, Lei; Wang, Jia; Song, Xin; Yuan, Ying; Chang, Fu-Ye; Wang, Chun-Ling
About 90% of tuberculosis (TB) patients latently infected with Mycobacterium tuberculosis (Mtb) show no symptoms, yet have a 10% chance in lifetime to progress active TB. Nevertheless, current diagnosis approaches need improvement in efficiency and sensitivity. The objective of this work was to detect potential signatures for active TB to further improve the understanding of the biological roles of functional modules involved in this disease. First, targeted networks of active TB and control groups were established via re-weighting protein-protein interaction (PPI) networks using Pearson's correlation coefficient (PCC). Candidate modules were detected from the targeted networks, and the modules with Jaccard score >0.7 were defined as attractors. After that, identification of dys-regulated modules was conducted from the attractors using attract method, Subsequently, gene oncology (GO) enrichment analyses were implemented for genes in the dys-regulated modules. We obtained 33 and 65 candidate modules from the targeted networks of control and active TB groups, respectively. Overall, 13 attractors were identified. Using the cut-off criteria of false discovery rate <0.05, there were 4 dys-regulated modules (Module 1, 2, 3, and 4). Based on the GO annotation results, genes in Modules 1, 2 and 4 were only involved in translation. Most genes in Module 1, 2 and 4 were associated with ribosomes. Accordingly, these dys-regulated modules might serve as potential biomarkers of active TB, facilitating the development for a more efficient, and sensitive diagnostic assay for active TB.
Caminero, José A
The management of patients with resistance to anti tuberculous drugs is complex and therefore must be managed by physician specialists. The most difficult patients are the cases in retreatment, where some very different possibilities are possible, as abandonment, failures and relapses. Patients with multi-drug resistant (MDR) tuberculosis are the most difficult to treat; MDR appears in all the failures or non-adherences to the treatment regime. To elaborate a scheme of retreatment for these patients, two guidelines must be followed: (1) do not rely on outcomes of drug susceptibility tests and (2) a detailed history of drug treatment must be considered of paramount importance. With this information, a retreatment scheme can be formulated that involves the use of at least three drugs not previously taken by the patient. For a successful control of tuberculosis, the national tuberculosis programs in Latin American countries must assure careful management of newly diagnosed patients. Secondly, if resources are available, a bank of second-line drugs must be ready for managing retreatment situations (e.g., 3 Z-Kn-Eth-Of/15 Z-Eth-Of) if first line drug treatments fail. Using individualized retreatment with second line drugs is recommended only in industrialized countries, and for a few middle income countries as a last resort.
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Cui, Zhezhe; Lin, Mei; Nie, Shaofa; Lan, Rushu
Background As one of the poorest provinces in China, Guangxi has a high HIV and TB prevalence, with the annual number of TB/HIV cases reported by health department among the highest in the country. However, studies on the burden of TB-HIV co-infection and risk factors for active TB among HIV-infected persons in Guangxi have rarely been reported. Objective To investigate the risk factors for active TB among people living with HIV/AIDS in Guangxi Zhuang autonomous region, China. Methods A surveillance survey was conducted of 1 019 HIV-infected patients receiving care at three AIDS prevention and control departments between 2013 and 2015. We investigated the cumulative prevalence of TB during 2 years. To analyze risk factors associated with active TB, we conducted a 1:1 pair-matched case-control study of newly reported active TB/HIV co-infected patients. Controls were patients with HIV without active TB, latent TB infection or other lung disease, who were matched with the case group based on sex and age (± 3 years). Results A total of 1 019 subjects were evaluated. 160 subjects (15.70%) were diagnosed with active TB, including 85 clinically diagnosed cases and 75 confirmed cases. We performed a 1:1 matched case-control study, with 82 TB/HIV patients and 82 people living with HIV/AIDS based on surveillance site, sex and age (±3) years. According to multivariate analysis, smoking (OR = 2.996, 0.992–9.053), lower CD 4+ T-cell count (OR = 3.288, 1.161–9.311), long duration of HIV-infection (OR = 5.946, 2.221–15.915) and non-use of ART (OR = 7.775, 2.618–23.094) were independent risk factors for TB in people living with HIV/AIDS. Conclusion The prevalence of active TB among people living with HIV/AIDS in Guangxi was 173 times higher than general population in Guangxi. It is necessary for government to integrate control planning and resources for the two diseases. Medical and public health workers should strengthen health education for TB/HIV prevention and
An estimated one third of the world's population is infected with Mycobacterium tuberculosis, and nearly 9 million persons develop disease caused by M. tuberculosis each year. Although tuberculosis (TB) occurs predominantly in resource-limited countries, it also occurs in the United States. During 1985-1992, the United States was confronted with an unprecedented TB resurgence. This resurgence was accompanied by a rise in multidrug-resistant TB (MDR TB), which is defined as TB that is resistant to the two most effective first-line therapeutic drugs, isoniazid and rifampin. In addition, virtually untreatable strains of M. tuberculosis are emerging globally. Extensively drug-resistant (XDR) TB is defined as MDR TB that also is resistant to the most effective second-line therapeutic drugs used commonly to treat MDR TB: fluoroquinolones and at least one of three injectable second-line drugs used to treat TB (amikacin, kanamycin, or capreomycin). XDR TB has been identified in all regions of the world, including the United States. In the United States, the cost of hospitalization for one XDR TB patient is estimated to average $483,000, approximately twice the cost for MDR TB patients. Because of the limited responsiveness of XDR TB to available antibiotics, mortality rates among patients with XDR TB are similar to those of TB patients in the preantibiotic era. In January 1992, CDC convened a Federal TB Task Force to draft an action plan to improve prevention and control of drug-resistant TB in the United States (CDC. National action plan to combat multidrug-resistant tuberculosis. MMWR 1992;41([No. RR-11]). In November 2006, CDC reconvened the Task Force to draft an updated action plan to address the issue of MDR TB and XDR TB. Task Force members were divided into nine response areas and charged with articulating the most pressing problems, identifying barriers to improvement, and recommending specific action steps to improve prevention and control of XDR TB within their
Winje, Brita Askeland; Oftung, Fredrik; Korsvold, Gro Ellen; Mannsåker, Turid; Jeppesen, Anette Skistad; Harstad, Ingunn; Heier, Berit Tafjord; Heldal, Einar
Background QuantiFERON®TB Gold (QFT) is a promising blood test for tuberculosis infection but with few data so far from immigrant screening. The aim of this study was to compare results of QFT and tuberculin skin test (TST) among newly arrived asylum seekers in Norway and to assess the role of QFT in routine diagnostic screening for latent tuberculosis infection. Methods The 1000 asylum seekers (age ≥ 18 years) enrolled in the study were voluntarily recruited from 2813 consecutive asylum seekers arriving at the national reception centre from September 2005 to June 2006. Participation included a QFT test and a questionnaire in addition to the mandatory TST and chest X-ray. Results Among 912 asylum seekers with valid test results, 29% (264) had a positive QFT test whereas 50% (460) tested positive with TST (indurations ≥ 6 mm), indicating a high proportion of latent infection within this group. Among the TST positive participants 50% were QFT negative, whereas 7% of the TST negative participants were QFT positive. There was a significant association between increase in size of TST result and the likelihood of being QFT positive. Agreement between the tests was 71–79% depending on the chosen TST cut-off and it was higher for non-vaccinated individuals. Conclusion By using QFT in routine screening, further follow-up could be avoided in 43% of the asylum seekers who would have been referred if based only on a positive TST (≥ 6 mm). The proportion of individuals referred will be the same whether QFT replaces TST or is used as a supplement to confirm a positive TST, but the number tested will vary greatly. All three screening approaches would identify the same proportion (88–89%) of asylum seekers with a positive QFT and/or a TST ≥ 15 mm, but different groups will be missed. PMID:18479508
Nuzzo, Jennifer B; Golub, Jonathan E; Chaulk, Patrick; Shah, Maunank
We sought to determine the proportion of refugee patients at the Baltimore City Health Department Tuberculosis program (BCHD-TB) successfully completing latent tuberculosis infection (LTBI) treatment, as compared to other referral groups, and to identify factors associated with treatment completion. We completed a retrospective cohort analysis of individuals referred to BCHD-TB program for LTBI care between February 1, 2009 and March 31, 2011. Among 841 patients evaluated by BCHD-TB and diagnosed with LTBI, 81% of refugees, 50% of non-refugee foreign-born, and 35% of US-born patients completed LTBI treatment. In multivariate analysis, refugees had greater odds of LTBI treatment completion (Adjusted Odds Ratio 7.2; 95% CI 4.2-12.4, p < 0.001) compared to US-born individuals adjusting for age, gender, and treatment regimen. Overall, LTBI treatment completion remains suboptimal. At BCHD-TB, LTBI treatment completion was significantly higher among refugees than other referral groups. Additional efforts are needed to optimize LTBI care, and future efforts may need to be tailored for different risk groups.
Dlugovitzky, D; Bay, M L; Rateni, L; Fiorenza, G; Vietti, L; Farroni, M A; Bottasso, O A
Earlier studies in patients with pulmonary TB have revealed a higher production of Th1 cell type cytokines in moderate TB, with predominant Th2-like responses in advanced disease. Given the influence of IL-12 in T cell differentiation, as well as the roles of transforming growth factor-beta (TGF-beta), nitric oxide and tumour necrosis factor-alpha (TNF-alpha) in the immune response against intracellular pathogens, we decided to analyse the interferon-gamma (IFN-gamma), IL-4, IL-12, TGF-beta, TNF-alpha and nitrite concentrations in culture supernatants of PBMC from TB patients showing different degrees of lung involvement. The sample population comprised 18 untreated TB patients with either moderate (n = 9) or advanced (n = 9) disease and 12 age- and sex-matched healthy controls (total population (patients and controls) 12 women, 18 men, aged 37 +/- 13 years (mean +/- s.d.)). PBMC were stimulated with whole sonicate from Mycobacterium tuberculosis and the supernatants were collected on day 4 for measurement of cytokine and nitrite levels. Antigen-stimulated IFN-gamma, TGF-beta and TNF-alpha production was found to be significantly increased in TB patients, both moderate and advanced, compared with the controls. Levels of IFN-gamma were significantly higher in moderate disease than advanced cases, whereas advanced cases showed significantly higher IL-12, TGF-beta and TNF-alpha concentrations when compared with cases of moderate TB. Nitrite levels were also increased in TB patients and the increase was statistically significant when advanced cases were compared with controls. These findings may contribute to a clearer picture of the net effect of cytokine interactions in TB, essential for a better understanding of the immunopathological mechanisms underlying the distinct clinical forms of the disease.
Dlugovitzky, D; Bay, M L; Rateni, L; Fiorenza, G; Vietti, L; Farroni, M A; Bottasso, O A
Earlier studies in patients with pulmonary TB have revealed a higher production of Th1 cell type cytokines in moderate TB, with predominant Th2-like responses in advanced disease. Given the influence of IL-12 in T cell differentiation, as well as the roles of transforming growth factor-beta (TGF-β), nitric oxide and tumour necrosis factor-alpha (TNF-α) in the immune response against intracellular pathogens, we decided to analyse the interferon-gamma (IFN-γ), IL-4, IL-12, TGF-β, TNF-α and nitrite concentrations in culture supernatants of PBMC from TB patients showing different degrees of lung involvement. The sample population comprised 18 untreated TB patients with either moderate (n = 9) or advanced (n = 9) disease and 12 age- and sex-matched healthy controls (total population (patients and controls) 12 women, 18 men, aged 37 ± 13 years (mean ±s.d.)). PBMC were stimulated with whole sonicate from Mycobacterium tuberculosis and the supernatants were collected on day 4 for measurement of cytokine and nitrite levels. Antigen-stimulated IFN-γ, TGF-β and TNF-α production was found to be significantly increased in TB patients, both moderate and advanced, compared with the controls. Levels of IFN-γ were significantly higher in moderate disease than advanced cases, whereas advanced cases showed significantly higher IL-12, TGF-β and TNF-α concentrations when compared with cases of moderate TB. Nitrite levels were also increased in TB patients and the increase was statistically significant when advanced cases were compared with controls. These findings may contribute to a clearer picture of the net effect of cytokine interactions in TB, essential for a better understanding of the immunopathological mechanisms underlying the distinct clinical forms of the disease. PMID:11122239
Screening for latent tuberculosis infection in psoriasis and psoriatic arthritis patients in a tuberculosis-endemic country: a comparison of the QuantiFERON®-TB Gold In-Tube test and tuberculin skin test.
Duman, Nilay; Ersoy-Evans, Sibel; Karadağ, Omer; Aşçıoğlu, Sibel; Sener, Burçin; Kiraz, Sedat; Sahin, Sedef
Since the introduction of biologic therapies for tuberculosis (TB), screening for latent TB infection has increased in importance, especially in countries in which TB is endemic. The aim of this study was to evaluate the effect of psoriasis on tuberculin skin test (TST) results and to compare two TB screening tests, the TST and QuantiFERON(®)-TB Gold In-Tube (QFT-GIT) test, in psoriasis and psoriatic arthritis (PA) patients living in a TB-endemic country (Turkey). This prospective study included 61 psoriasis and 40 PA patients, and 58 healthy controls. Demographic data, medical history, human immunodeficiency virus (HIV) status, level of education, smoking status, exposure to TB, personal and family histories of TB, and bacillus Calmette-Guérin (BCG) vaccination status were recorded for all participants. The TST and QFT-GIT were performed in all participants. The mean ± standard deviation TST indurations in the patient and control groups were 12.6 ± 6.4 mm and 10.2 ± 6.5 mm, respectively (P = 0.051). The TST positivity rate was higher in patients than in controls (86.1% vs. 37.9%; P < 0.001), whereas QFT-GIT positivity did not differ significantly (patients: 20.8%; controls: 17.2%; P = 0.737). False positive results can lead to unnecessary prophylactic TB treatment; therefore, the cut-off point for TST positivity in psoriasis and PA patients should be re-evaluated, or other tests, such as the QFT-GIT, should be used.
Wang, Linchuan; Yu, Yan; Chen, Wei; Feng, Jin; Wang, Jinyuan; Zhao, Heping; Ma, Lietin; Yang, Bo; Ma, Yanfen; Dang, Pei
The purpose of this study was to evaluate the characteristics of the T-SPOT.TB test for the diagnosis of active tuberculosis (ATB) and to distinguish ATB from other diseases using a receiver operating characteristic (ROC) curve. A total of 535 patients with suspected active tuberculosis were enrolled in the study and divided into ATB and nonactive tuberculosis (NATB) groups, as well as pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) subgroups. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of the T-SPOT.TB test for the diagnosis of ATB were 84.95%, 85.12%, 82.94%, 86.93%, 5.71, and 0.18, respectively. The median number of spot-forming cells (SFCs) in the ATB group was higher than that in the NATB group (71 versus 1; P < 0.0001). The sensitivities in the PTB and EPTB subgroups were 92.31% and 81.77%. The areas under the curve (AUC) for the diagnosis of ATB using the T-SPOT.TB, early secreted antigenic target 6 (ESAT-6), and culture filtrate protein 10 (CFP-10) were 0.906, 0.884, and 0.877, respectively. A cutoff of 42.5 SFCs for ATB yielded a positive predictive value of 100%. Our study shows that the T-SPOT.TB test is useful for the diagnosis of ATB. Utilizing an ROC curve to select an appropriate cutoff made it possible to discriminate ATB from NATB.
Oh, Su-Young; Song, Ji-Hee; Gil, Jung-Eun; Kim, Jeong-Hee; Yeom, Young-Il; Moon, Eun-Yi
The development of paclitaxel-resistance in tumors is one of the most significant obstacles to successful therapy. Thymosin-beta-4 (TB4) has been known as actin-sequestering protein and functions in tumor metastasis. Here, we overexpressed TB4 in HeLa cells (TB4-HeLa) and examined the effect of TB4 in paclitaxel-induced cell death. TB4-HeLa cells showed a higher growth rate and a lower percentage of basal apoptosis than HeLa cells. TB4-HeLa cells were more resistant to paclitaxel-induced cell death than HeLa cells. TB4 transcript expression with paclitaxel treatment was dose-dependently increased in HeLa cells but that was not in TB4-HeLa cells. Small interfering RNA (siRNA) of TB4 inhibited HeLa cell growth and enhanced paclitaxel-induced cell death. Basal ERK phosphorylation was elevated and basal p38 kinase phosphorylation was reduced in paclitaxel non-treated TB4-HeLa cells. When treated with paclitaxel, cell death and resistance-induction were independent of ERK and p38 kinase activation. Paclitaxel-resistance of TB4-HeLa cells was overcome by the inhibition of basal ERK activity with PD98059 pre-treatment. The inhibition of basal p38 kinase activity with SB203580 pre-treatment attenuated the paclitaxel-induced HeLa cell death. In conclusion, TB4 induced paclitaxel-resistance through the elevation of basal level of ERK phosphorylation. Therefore, TB4 could be a novel target to regulate paclitaxel-resistance.
Currie, Christine S M; Hoad, Kathryn A
We analyse the tuberculosis (TB) epidemics of 211 countries with a view to proposing more efficient and targeted TB control strategies. Countries are classified by how their TB case notification rates have evolved over time and the age distribution of those suffering from active TB disease in 2008. Further analysis of key statistics associated with each of the countries shows the impact of different indicators. As expected, HIV is a key driver of TB epidemics and affects their age-distribution and their scale. The level of development of a country and its wealth also vary with the shape and scale of a country's TB epidemic. Immigration has an influence on the shape of TB epidemics, which is particularly pronounced in highly developed countries with low levels of TB disease in the native population. We conclude by proposing how the TB control programme in each country analysed should prioritise its efforts.
Ali, Solomon; Haileamlak, Abraham; Wieser, Andreas; Pritsch, Michael; Heinrich, Norbert; Loscher, Thomas; Hoelscher, Michael; Rachow, Andrea
Setting Tuberculosis (TB) is one of the major health problems in prisons. Objective This study was done to assess the prevalence and determinants of active tuberculosis in Ethiopian prisons. Design A cross-sectional study was conducted from January 2013 to December 2013 in 13 zonal prisons. All incarcerated inmates underwent TB symptom screening according to WHO criteria. From identified TB-suspects two sputum samples were analyzed using smear microscopy and solid culture. A standardized questionnaire assessing TB risk factors was completed for each TB suspect. Results 765 (4.9%) TB suspects were identified among 15,495 inmates. 51 suspects were already on anti-TB treatment (6.67%) and 20 (2.8%) new culture-confirmed TB cases were identified in the study, resulting in an overall TB prevalence of 458.1/100,000 (95%CI: 350-560/100,000). Risk factors for active TB were alcohol consumption, contact with a TB case before incarceration and no window in prison cell. HIV prevalence was not different between TB suspects and active TB cases. Further, the TB burden in prisons increased with advancing distance from the capital Addis Ababa. Conclusions The overall TB prevalence in Ethiopian prisons was high and extremely variable among different prisons. TB risk factors related to conditions of prison facilities and the impact of implemented TB control measures need to be further studied in order to improve TB control among inmates. PMID:26641654
Díaz Rojas, F; Córdova Gutiérrez, H; Aguirre Gas, H
This paper reviewed 8 cases of spontaneous pneumothorax, associated to pulmonary tuberculosis during a period of time of two years at the A.L.M. General Hospital of Toluca, Mex. The diagnosis was confirmed by clinical picture, radiology and bacteriology studies. Six males and two females proceding of the low class; farmers all of them. Their age ranged between 18 and 35 years. Two of the patients showed cavitary lesions, five had difusse fibrosis of the lung. We analized the clinical manifestations and reviewed the pathogenic mechanisms as well the medical and surgical treatment. No deaths ocurred en this series. We concluded that the direct relation between active pulmonary tuberculosis and spontaneous pneumothorax is not clear, but their association in this serie suggested further studies to stablished this. We emphasized the importance of this complication rare in the world literature.
Ben Selma, Walid; Harizi, Hedi; Bougmiza, Iheb; Hannachi, Naila; Ben Kahla, Imen; Zaieni, Radhia; Boukadida, Jalel
Interferon gamma (IFN-γ) is a key cytokine involved mainly in the defense against intracellular pathogens such as Mycobacterium tuberculosis. Given its key role in the control of tuberculosis (TB), in the present article we have investigated a possible association between IFN-γ gene single-nucleotide polymorphism linked to high and low producer phenotypes (IFN-γ [+874T(high) → A(low)]) (rs2430561) and risk development of active TB in Tunisian patients. Genomic DNA samples were obtained from 223 patients with active TB (168 pulmonary and 55 extrapulmonary cases) and 150 healthy blood donors. Genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism method. The +874 AA genotype (low IFN-γ producer) was significantly associated with increased risk of developing of active pulmonary TB (odds ratio [OR] = 2.18; 95% confidence intervals [CI], 1.33-3.57; P corrected for the number of genotypes [Pc] = 0.003). By contrast, the AT genotype was found to be significantly associated with resistance to pulmonary TB (OR = 0.46; 95% CI, 0.28-0.74; Pc = 0.0018) and extrapulmonary TB development (OR = 0.46; 95% CI, 0.23-0.91; Pc = 0.045). Collectively, our data showed that the IFN-γ +874T/A polymorphism is a determinant in the resistance or susceptibility to the development of active TB in the studied population.
Ginsberg, Ann M.
Over the past 10 years, tuberculosis (TB) vaccine development has resurged as an active area of investigation. The renewed interest has been stimulated by the recognition that, although BCG is delivered to approximately 90% of all neonates globally through the Expanded Programme on Immunization, Mycobacterium tuberculosis continues to cause over 8 million new cases of TB and over 2 million deaths annually. Over one hundred TB vaccine candidates have been developed, using different approaches to inducing protective immunity. Candidate vaccines are typically screened in small animal models of primary TB disease for their ability to protect against a virulent strain of M. tuberculosis. The most promising are now beginning to enter human safety trials, marking real progress in this field for the first time in 80 years. PMID:12132007
Kerr, Joanne; Elwell, Jack
Points out the importance of effective health education to fight against tuberculosis (TB) which is the number one fatal infectious disease around the world. Describes a science curriculum on tuberculosis that includes information on the facts about tuberculosis, a forum on tuberculosis, and evaluation. (Contains 17 references.) (YDS)
Vincenti, D; Carrara, S; Butera, O; Bizzoni, F; Casetti, R; Girardi, E; Goletti, D
Tuberculosis is the most frequent co-infection in human immunodeficiency virus (HIV)-infected individuals, and which still presents diagnostic difficulties. Recently we set up an assay based on interferon (IFN)-γ response to region of difference 1 (RD1) peptides selected by computational analysis which is associated with active Mycobacterium tuberculosis replication. The objective of this study was to investigate the response to RD1 selected peptides in HIV-1-infected individuals in a clinical setting. The mechanisms of this immune response and comparison with other immune assays were also investigated. A total of 111 HIV-infected individuals with symptoms and signs consistent with active tuberculosis were enrolled prospectively. Interferon (IFN)-γ responses to RD1 selected peptides and recall antigens were evaluated by enzyme-linked immunospot assay. Results were correlated with CD4− T cell counts, individuals' characteristics, tuberculin skin test, QuantiFERON-TB Gold and T-SPOT.TB. Results from 21 (19%) individuals were indeterminate due to in vitro cell anergy. Among ‘non-anergic’ individuals, sensitivity for active tuberculosis of the assay based on RD1 selected peptides was 67% (24 of 36), specificity was 94% (three of 54). The assay also resulted positive in cases of extra-pulmonary and smear-negative pulmonary active tuberculosis. The response was mediated by CD4− effector/memory T cells and correlated with CD4− T cell counts, but not with plasma HIV-RNA load. Moreover, the RD1 selected peptides assay had the highest diagnostic odds ratio for active tuberculosis compared to tuberculin skin test (TST), QuantiFERON-TB Gold and T-SPOT.TB. RD1 selected peptides assay is associated with M. tuberculosis replication in HIV-infected individuals, although T cell anergy remains an important obstacle to be overcome before the test can be proposed as a diagnostic tool. PMID:17680823
Roberts, Julia; Ling, Yan; Quezada, Landys Lopez; Glasheen, Jou; Ballinger, Elaine; Somersan-Karakaya, Selin; Warrier, Thulasi; Warren, J. David; Nathan, Carl
The search for drugs that can kill replicating and nonreplicating Mycobacterium tuberculosis faces practical bottlenecks. Measurement of CFU and discrimination of bacteriostatic from bactericidal activity are costly in compounds, supplies, labor, and time. Testing compounds against M. tuberculosis under conditions that prevent the replication of M. tuberculosis often involves a second phase of the test in which conditions are altered to permit the replication of bacteria that survived the first phase. False-positive determinations of activity against nonreplicating M. tuberculosis may arise from carryover of compounds from the nonreplicating stage of the assay that act in the replicating stage. We mitigate these problems by carrying out a 96-well microplate liquid MIC assay and then transferring an aliquot of each well to a second set of plates in which each well contains agar supplemented with activated charcoal. After 7 to 10 days—about 2 weeks sooner than required to count CFU—fluorometry reveals whether M. tuberculosis bacilli in each well have replicated extensively enough to reduce a resazurin dye added for the final hour. This charcoal agar resazurin assay (CARA) distinguishes between bacterial biomasses in any two wells that differ by 2 to 3 log10 CFU. The CARA thus serves as a pretest and semiquantitative surrogate for longer, more laborious, and expensive CFU-based assays, helps distinguish bactericidal from bacteriostatic activity, and identifies compounds that are active under replicating conditions, nonreplicating conditions, or both. Results for 14 antimycobacterial compounds, including tuberculosis (TB) drugs, revealed that PA-824 (pretomanid) and TMC207 (bedaquiline) are largely bacteriostatic. PMID:26239979
The purpose of our study was to investigate the association between a functional single nucleotide polymorphism (SNP) in the interleukin-23 receptor gene (IL23R; rs11209026, 1142 Gwild type → Areduced function, Arg381Gln) and disease severity outcome in pulmonary tuberculosis (TB) in the Tunisian population. SNP was investigated in a population of 168 patients with active pulmonary TB (cases were stratified into patients with minimal/moderate lung involvement, i.e., patients with minimal/moderate disease [Pmd], and patients with extensive lung involvement, i.e., patients with active disease [Pad]) and 150 healthy subjects. Genotype analyses were carried out using the PCR-restriction fragment length polymorphism method. We have found that the IL23R reduced-function allele 1142A and genotypes AA and AG were overrepresented, especially in the Pad subgroup compared with the control group (51% versus 18% [P = 10−8], 33% versus 5% [P = 10−8], and 36% versus 26% [P = 5 × 10−3], respectively). Additionally, comparison of the Pad and the Pmd groups showed that the A allele and AA genotype seemed to be associated with 2.79-fold (P = 4 × 10−5) and 7.74-fold (P = 10−5) increased risks of TB with minimal/moderate lung involvement, respectively. Our results demonstrate that the reduced-function polymorphism 1142G → A encoded by IL23R influences the outcome of disease severity of active pulmonary TB in Tunisian patients. PMID:22695161
Tsenova, Liana; O'Brien, Paul; Holloway, Jennifer; Peixoto, Blas; Soteropoulos, Patricia; Fallows, Dorothy; Subbian, Selvakumar
Treatment of chronic inflammatory diseases with tumor necrosis factor alpha (TNF-α) antagonists has been associated with increased risk of tuberculosis (TB). We examined the usefulness of the rabbit model of active pulmonary TB for studying the impact of the human immune modulatory reagent etanercept on the host immune response. Control of Mycobacterium tuberculosis (Mtb) infection, disease pathology, and the global transcriptional response in Mtb-infected lungs of rabbits were studied. Etanercept treatment exacerbated disease pathology and reduced bacillary control in the lungs, compared with infected untreated animals. Reduced collagen and fibrin deposition in the granulomas was associated with significant downregulation of the collagen metabolism and fibrosis network genes and upregulation of genes in the inflammatory response and cell recruitment networks in the lungs of etanercept treated, compared with untreated rabbits. Our results suggest that targeting the TNF-α signaling pathway disrupts the tissue remodeling process, which is required for the formation and maintenance of well-differentiated granulomas and for control of Mtb growth in the lungs. These results validate the use of the rabbit model for investigating the impact of selected human immune modulatory drugs, such as a TNF-α antagonist, on the host immune response and pathogenesis in TB. PMID:24831609
Rodrigues, Liliana; Machado, Diana; Couto, Isabel; Amaral, Leonard; Viveiros, Miguel
Resistance to isoniazid (INH), one of the main drugs used in tuberculosis (TB) therapy, is mostly due to chromosomal mutations in target genes. However, approximately 20-30% of INH resistant Mycobacterium tuberculosis isolates do not have mutations in any of the genes associated with INH resistance. This suggests that other mechanism(s) may be involved, namely efflux pump systems capable of extruding the drug to the exterior of the cell. In a previous work, we have induced clinical INH susceptible M. tuberculosis isolates and the H37Rv reference strain to high-level resistance to INH, by gradual exposure to increasing concentrations of this drug. In the present study, we have characterized these strains and Mycobacterium bovis BCG induced to INH resistance with respect to their efflux activity and its contribution to INH resistance using the following approach: determination of the susceptibility to INH in the presence and absence of the efflux inhibitors (EIs) chlorpromazine, thioridazine and verapamil; evaluation of efflux activity by a semi-automated fluorometric method; and quantification of the expression level of genes coding for efflux pumps by real-time RT-qPCR. The EIs decreased INH resistance in the INH induced strains, in particular verapamil promoted a reversal of resistance in some of the strains tested. The induced strains presented an increased efflux activity that was inhibited by the EIs and showed overexpression of the efflux pump genes efpA, mmpL7, mmr, p55 and the Tap-like gene Rv1258c. Altogether, these results correlate efflux activity with INH resistance and demonstrate that efflux pumps play an important role in acquired INH resistance in M. tuberculosis complex. The development of EIs that can restore the antimicrobial activity of the antibiotic subject to efflux is an approach that can be useful in order to prevent the emergence of this resistance and guide the development of new effective anti-TB therapeutical approaches.
Currently, more than 9.0 million people develop acute pulmonary tuberculosis (TB) each year and about 1.5 million people worldwide die from this infection. Thus, developing vaccines to prevent active TB disease remains a priority. This article discusses recent progress in the development of new vaccines against TB and focusses on the main requirements for development of improved vaccines against Mycobacterium tuberculosis (M. tb). Over the last two decades, significant progress has been made in TB vaccine development, and some TB vaccine candidates have currently completed a phase III clinical trial. The potential public health benefits of these vaccines are possible, but it will need much more effort, including new global governance investment on this research. This investment would certainly be less than the annual global financial toll of TB treatment.
Background Tuberculosis (TB) is a global burden with one –third of the world’s population infected with the pathogen Mycobacterium tuberculosis complex and annually 1.4 million deaths occur due to the disease. This high incidence of infection and the increased rate of multi-drug resistant and extensively-drug resistant strains of the organism further complicated the problem of TB control and have called for an urgent need to develop new anti-TB drugs from plants. In this study, the in vitro activity of root of Calpurnia aurea, seeds of Ocimum basilicum, leaves of Artemisia abyssinica, Croton macrostachyus, and Eucalyptus camaldulensis were evaluated against M. tuberculosis and M. bovis strains. Methods Five Ethiopian medicinal plants, root of Calpurnia aurea, seeds of Ocimum basilicum, leaves of Artemisia abyssinica, Croton macrostachyus, and Eucalyptus camaldulensis used locally for the management of TB. They were investigated for in vitro antimycobacterial activity against M. tuberculosis and M. bovis strains. 80% methanolic extracts of the plant materials were obtained by maceration. The antimycobacterial activity was determined using 96 wells of microplate with the help of visual Resazurin Microtiter Assay. Results The crude 80% methanolic extracts of the root of C. aurea, seeds of O. basilicum, and leaves of A. abyssinica, C. macrostachyus, and E. camaldulensis had anti-mycobacterial activity with minimum inhibitory concentration (MIC) ranging from 6.25–100 μg/mL. The MIC of 80% methanol extracts in the order mentioned above ranged 25-100 μg/ml and 12.5-75 μg/mL, 25–100 μg/mL and 25–50 μg/mL, 6.25-50 μg/mL and 12.5-50 μg/mL, 12.5-100 μg/mL and 18.25-50 μg/mL and 6.25-50 μg/mL and 12.5-50 μg/mL, respectively for M. tuberculosis and M. bovis strains. Conclusions The results support the local use of these plants in the treatment of TB and it is suggested that these plants may have therapeutic value in the treatment of TB. However
Min, Joo-Won; Lee, Ha-Youn; Lee, Ji Sun; Lee, Jinwoo; Chung, Jae Ho; Han, Sung Koo; Yim, Jae-Joon
Previous reports have shown that the sensitivity of the 6-day lymphocyte stimulation test is much higher than those of commercially available gamma interferon release assays (IGRAs). The aim of this study was to elucidate the effect of prolonged incubation on the results of the QuantiFERON TB Gold in-tube (QFT-GIT) assay. Patients aged >20 years with suspected tuberculosis (TB) were recruited prospectively from 1 May 2009 to 31 December 2010. In addition, healthy volunteers with no history of TB treatment were included as controls. For each participant, three sets of the QFT-GIT assay were performed using 24-, 48-, and 72-h incubation tests, and the results were compared. Thirty-seven patients with suspected pulmonary TB and 33 healthy controls were enrolled in the study. Of the 37 patients with suspected TB, the QFT-GIT assay results were positive for 28 (75.7%) after a 24-h incubation period. After prolonged incubation, the results differed in four (10.8%) of the 37 patients suspected of having TB. Among 27 patients with culture-confirmed TB, the sensitivities of the QFT-GIT assay after the 24-, 48-, and 72-h incubation tests were 85.2%, 81.5%, and 81.5%, respectively. Among the 33 healthy controls, the QFT-GIT assay results were positive in two (6.1%) after a 24-h incubation period. The results changed for two (6.1%) of the 33 healthy controls after prolonged incubation. The specificities of the QFT-GIT assay after 24, 48, and 72 h of incubation were 93.9%, 87.9%, and 90.9%, respectively. Prolonging the incubation time did not increase the sensitivity of the QFT-GIT assay. The manufacturer-recommended incubation time of 16 to 24 h should be respected because prolonged incubation can cause indeterminate or false-positive results.
Anggriani, N.; Wicaksono, B. C.; Supriatna, A. K.
Tuberculosis (TB) is one of the deadliest infectious disease in the world which caused by Mycobacterium tuberculosis. The disease is spread through the air via the droplets from the infectious persons when they are coughing. The World Health Organization (WHO) has paid a special attention to the TB by providing some solution, for example by providing BCG vaccine that prevent an infected person from becoming an active infectious TB. In this paper we develop a mathematical model of the spread of the TB which assumes endogeneous reactivation and exogeneous reinfection factors. We also assume that some of the susceptible population are vaccinated. Furthermore we investigate the optimal vaccination level for the disease.
For centuries the treatment of TB has presented an enormous challenge to global health. In the 20th century, the treatment of TB patients with long-term multidrug therapy gave hope that TB could be controlled and cured; however, contrary to these expectations and coinciding with the emergence of AIDS, the world has witnessed a rampant increase in hard-to-treat cases of TB, along with the emergence of highly virulent and multidrug-resistant Mycobacterium tuberculosis strains. Unfortunately, these bacteria are now circulating around the world, and there are few effective drugs to treat them. As a result, the prospects for improved treatment and control of TB in the 21st century have worsened and we urgently need to identify new therapies that deal with this problem. The potential use of immunotherapy for TB is now of greater consideration than ever before, as immunotherapy could potentially overcome the problem of drug resistance. TB immunotherapy targets the already existing host anti-TB immune response and aims to enhance killing of the bacilli. For this purpose, several approaches have been used: the use of anti-Mycobacteria antibodies; enhancing the Th1 protective responses by using mycobacterial antigens or increasing Th1 cytokines; interfering with the inflammatory process and targeting of immunosuppressive pathways and targeting the cell activation/proliferation pathways. This article reviews our current understanding of TB immunity and targets for immunotherapy that could be used in combination with current TB chemotherapy.
Chiacchio, T; Casetti, R; Butera, O; Vanini, V; Carrara, S; Girardi, E; Di Mitri, D; Battistini, L; Martini, F; Borsellino, G; Goletti, D
Forkhead box P3 (FoxP3) is a transcription factor whose expression characterizes regulatory T cells (Treg), but it is also present on activated T cells, thus hindering correct Treg identification. Using classical markers for Treg recognition, discordant results were found in terms of Treg expansion during active tuberculosis (TB) disease. Recently CD39 has been shown to be an accurate marker for Treg detection. The objectives of this study were: (i) to identify Treg expressing CD39 in patients with TB and to compare the results with those obtained by the standard phenotypic markers; (ii) to evaluate if Treg are expanded in vitro by exogenous interleukin (IL)-2 or by antigen-specific stimulation; and (iii) to characterize Treg function on the modulation of antigen-specific responses. We enrolled 13 patients with pulmonary TB and 12 healthy controls. Treg were evaluated by flow cytometry ex vivo and after antigen-specific in vitro stimulation using CD25, FoxP3, CD127 and CD39 markers. Results indicate that CD39+ cells within the CD4+CD25high cells have Treg properties (absence of interferon-γ production and transforming growth factor-β1 release upon stimulation). Ex vivo analysis did not show significant differences between TB patients and controls of Treg by classical or novel markers. In contrast, a significantly higher percentage of Treg was found in TB patients after antigen-specific stimulation both in the presence or absence of IL-2. Depletion of CD39+ Treg increased RD1-specific responses significantly. In conclusion, CD39 is an appropriate marker for Treg identification in TB. These results can be useful for future studies to monitor Mycobacterium tuberculosis-specific response during TB. PMID:19438599
Capone, Domenico; Mafort, Thiago; Mogami, Roberto; Rodrigues, Rosana de Souza; Menna Barreto, Miriam
Objectives. To evaluate tomographic changes in pulmonary tuberculosis (TB), degree of agreement among three radiologists regarding tomographic diagnoses, and sequelae following treatment. Methods. Cross-sectional and descriptive study of 74 TB patients confirmed by sputum culture and chest computed tomography before (CT1) and 6 months after (CT2) drug therapy. Results were performed by three radiologists blinded to clinical and laboratory results. Results. Main findings in CT1 included nodules indicating the presence of a tree-in-bud pattern in 93% of cases, ill-defined nodules in 84% of cases, consolidation in 77% of cases, architectural distortion in 71% of cases, cavitary lesions in 62% of cases, and ground glass opacities in 37% of cases. Airway involvement, characterized by increased thickness and dilatation of the bronchial walls, occurred in 93% of cases. Pleural involvement occurred in 54%. There was an agreement on active TB among the three radiologists in 85% of cases. The results in CT2 indicated the presence of architectural distortion in 91% of cases and cylindrical bronchiectasis in 86%. Conclusions. The study established a tomographic pattern for diagnosis of active TB characterized by the presence of airway nodules, consolidation, architectural distortion, and cavitary lesions, and an almost complete degree of agreement (Kappa) was observed among the radiologists (0.85). CT after treatment assists in defining the cure. PMID:28261498
Background In tuberculosis (TB), the steadily increasing bacterial resistance to existing drugs and latent TB continue to be major concerns. A combination of conventional drugs and plant derived therapeutics can serve to expand the antimicrobial spectrum, prevent the emergence of drug resistant mutants and minimize toxicity. Alpinia galanga, used in various traditional medicines, possesses broad spectrum antibacterial properties. The study was undertaken to assess the antimycobacterial potential of A. galanga in axenic (under aerobic and anaerobic conditions) and intracellular assays. Methods Phytochemical analysis was done using HPTLC. The acetone, aqueous and ethanolic extracts (1, 10, 25, 50 and 100 μg/ml) of A. galanga were tested axenically using Microplate Alamar Blue Assay (MABA) against Mycobacterium tuberculosis (M.tb) H37Rv and three drug sensitive and three multi drug resistant clinical isolates. The activity of the extracts was also evaluated intracellularly in A549 cell line against these strains. The extracts active under intracellular conditions were further tested in an axenic setup under reducing oxygen concentrations using only H37Rv. Results 1´ acetoxychavicol acetate, the reference standard used, was present in all the three extracts. The acetone and ethanolic extracts were active in axenic (aerobic and anaerobic) and intracellular assays. The aqueous extract did not demonstrate activity under the defined assay parameters. Conclusion A. galanga exhibits anti M.tb activity with multiple modes of action. Since the activity of the extracts was observed under reducing oxygen concentrations, it may be effective in treating the dormant and non-replicating bacteria of latent TB. Though the hypothesis needs further testing, A. galanga being a regular dietary component may be utilized in combination with the conventional TB therapy for enhanced efficacy. PMID:24592852
Feldacker, C.; Tweya, H.; Keiser, O.; Weigel, R.; Kalulu, M.; Fenner, L.; Egger, M.; Manda, E.; Mwafilaso, J. B.; Kamba, C.; Phiri, S.
Objectives To describe initial registration characteristics of adult and pediatric TB patients at a large, public, integrated TB and HIV clinic in Lilongwe, Malawi, between January 2008 – December 2010. Methods Routine data on TB patient category and TB type, stratified by HIV and ART status, were used to explore differences in proportions among TB-only, TB/HIV co-infected patients not on ART, and TB/HIV co-infected patients on ART using Chi-square tests.. Trends over time illustrate strengths and weaknesses of integrated service provision. Results Among 10,143 adults, HIV ascertainment and ART uptake were high and increased over time. The proportion of relapse was highest among those on ART (5%). The proportion of smear-positive pulmonary TB (PTB) was highest among HIV-negative TB patients (34.9%); extra-pulmonary TB (EPTB) was lowest among TB-only (16.2%). Among 338 children <15 years, EPTB and smear-positive PTB were more common among TB-only patients. Time trends showed significant increases in the proportion of adults with smear-positive PTB and the proportion of adults already on ART before starting TB treatment. However, some co-infected patients still delay ART initiation. Conclusions HIV ascertainment and ART uptake among co-infected patients is successful and improving over time. However, delays in ART initiation indicate some weakness linking TB/HIV patients into ART during TB follow-up care. Improved TB diagnostics and screening efforts, especially for pediatric patients, may help improve quality care for co-infected patients. These results may aid efforts to prioritize TB and HIV prevention, education, and treatment campaigns for specific populations. PMID:22808948
Turusbekova, N; Ljungqvist, I; Davidavičiene, E; Mikaityte, J; van der Werf, M J
Tuberculosis (TB) infection control (IC) is key in controlling TB transmission in health facilities in Lithuania. This article presents a project that aimed at supporting health care facilities in Lithuania in implementing TB-IC. The project consisted of 1) facility TB-IC assessments, 2) development of facility TB-IC plans, 3) TB-IC training and 4) site visits. We assessed the impact of these activities through a self-assessment questionnaire. The project resulted in limited improvements. Most progress was seen in administrative and managerial activities. Possible reasons for the limited improvements are challenges with funding and the lack of supportive legislation and a national TB-IC plan.
de la Barrera, S; Aleman, M; Musella, R; Schierloh, P; Pasquinelli, V; Garcia, V; Abbate, E; Sasiain, M del C
Activation of T cells requires both TCR-specific ligation and costimulation through accessory molecules during T cell priming. IFNgamma is a key cytokine responsible for macrophage activation during Mycobacterium tuberculosis (Mtb) infection while IL-10 is associated with suppression of cell mediated immunity in intracellular infection. In this paper we evaluated the role of IFNgamma and IL-10 on the function of cytotoxic T cells (CTL) and on the modulation of costimulatory molecules in healthy controls and patients with active tuberculosis (TB). gamma-irradiated-Mtb (i-Mtb) induced IL-10 production from CD14(+) cells from TB patients. Moreover, CD3(+) T cells of patients with advanced disease also produced IL-10 after i-Mtb stimulation. In healthy donors, IL-10 decreased the lytic activity of CD4(+) and CD8(+) T cells whereas it increased gammadelta-mediated cytotoxicity. Furthermore, we found that the presence of IL-10 induced a loss of the alternative processing pathways of antigen presentation along with a down-regulation of the expression of costimulatory molecule expression on monocytes and macrophages from healthy individuals. Conversely, neutralization of endogenous IL-10 or addition of IFNgamma to either effector or target cells from TB patients induced a strong lytic activity mediated by CD8(+) CTL together with an up-regulation of CD54 and CD86 expression on target cells. Moreover, we observed that macrophages from TB patients could use alternative pathways for i-Mtb presentation. Taken together, our results demonstrate that the presence of IL-10 during Mtb infection might contribute to mycobacteria persistence inside host macrophages through a mechanism that involved inhibition of MHC-restricted cytotoxicity against infected macrophages.
Faksri, Kiatichai; Drobniewski, Francis; Nikolayevskyy, Vladyslav; Brown, Timothy; Prammananan, Therdsak; Palittapongarnpim, Prasit; Prayoonwiwat, Naraporn; Chaiprasert, Angkana
Mycobacterium tuberculosis (MTB) strains were isolated from cerebrospinal fluids collected from individual tuberculous meningitis (TBM) patients from 1996 to 2007 (n = 184) and characterised based on IS6110-restriction fragment length polymorphism (RFLP), spoligotyping, Mycobacterium interspersed repetitive unit-variable number of tandem repeat (MIRU-VNTR) and large sequence polymorphisms (LSPs). Beijing strains were found to possess the highest transmissibility and proportion in clustered isolates. Beijing strain predomination and stability, at 56% of the genotypic proportion, as well as association with drug resistance in TBM patients, was demonstrated. The proportion of Beijing sublineages revealed that the modern Beijing sublineage showed an increasing trend, whereas the ancestral Beijing sublineage showed a decreasing trend across the three periods. In contrast, there were neither clustered nor multidrug-resistance (MDR) isolates from the Euro-American (EuA) lineage, and the lineage genotypic proportion trend was also decreased. Based on LSPs, only the Beijing, Indo-Oceanic and Euro-American lineages were identified from TBM patients in Thailand. TBM mortality rates were not associated with either drug resistance or significantly different among MTB lineages. This study may support the Beijing genotype strain as most pathogenic causing TBM, with the EuA lineage genotype as the most benign of the strain genotypes tested. The analysis of drug susceptibility also revealed the trend of increasing drug resistance, especially MDR, in TBM patients in Thailand.
Claassens, M. M.; Floyd, S.; Ayles, H.; Beyers, N.
Background High tuberculosis (TB) burden countries should consider systematic screening among adults in the general population. We identified symptom screening rules to be used in addition to cough ≥2 weeks, in a context where X-ray screening is not feasible, aiming to increase the sensitivity of screening while achieving a specificity of ≥85%. Methods We used 2010 Zambia South Africa Tuberculosis and HIV/AIDS Reduction (ZAMSTAR) survey data: a South African (SA) training dataset, a SA testing dataset for internal validation and a Zambian dataset for external validation. Regression analyses investigated relationships between symptoms or combinations of symptoms and active disease. Sensitivity and specificity were calculated for candidate rules. Results Among all participants, the sensitivity of using only cough ≥2 weeks as a screening rule was less than 25% in both SA and Zambia. The addition of any three of six TB symptoms (cough <2 weeks, night sweats, weight loss, fever, chest pain, shortness of breath), or 2 or more of cough <2 weeks, night sweats, and weight loss, increased the sensitivity to ~38%, while reducing specificity from ~95% to ~85% in SA and ~97% to ~92% in Zambia. Among HIV-negative adults, findings were similar in SA, whereas in Zambia the increase in sensitivity was relatively small (15% to 22%). Conclusion High TB burden countries should investigate cost-effective strategies for systematic screening: one such strategy could be to use our rule in addition to cough ≥2 weeks. PMID:28257424
Tuberculosis (TB) in animals and humans may result from exposure to bacilli within the Mycobacterium tuberculosis complex (i.e., M. tuberculosis, M. bovis, M. africanum, M. pinnipedii, M. microti, M. caprae, or M. canetti). Mycobacterium bovis is the species most often isolated from tuberculous catt...
Safdar, N; Hinderaker, S G; Baloch, N A; Enarson, D A; Khan, M A; Morkve, O
The control of childhood tuberculosis (TB) has been of low priority in TB programmes in high-burden settings. The objective of this paper was to describe the development and testing of tools for the management of childhood TB. The Pakistan National TB Control Programme embarked on a number of activities, including the establishment of policy guidelines for the management of childhood TB and later a guidance document, 'Case Management Desk Guide and Structured Monitoring', to demonstrate the implementation of childhood TB interventions in a programme context. Initial results showed improved case finding and treatment outcome in implementation sites compared with control districts. However, further programme attention is required to improve quality.
Little, Kristen M.; Pai, Madhukar; Dowdy, David W.
Background There is growing concern that interferon-γ release assays (IGRAs) are being used off-label for the diagnosis of active tuberculosis (TB) disease in many high-burden settings, including India, where the background prevalence of latent TB infection is high. We analyzed the costs and consequences of using IGRAs for the diagnosis of active TB in India from the perspective of the Indian TB control sector. Methods and Findings We constructed a decision analytic model to estimate the incremental cost and effectiveness of IGRAs for the diagnosis of active TB in India. We compared a reference scenario of clinical examination and non-microbiological tests against scenarios in which clinical diagnosis was augmented by the addition of either sputum smear microscopy, IGRA, or Xpert MTB/RIF. We examined costs (in 2013 US dollars) and consequences from the perspective of the Indian healthcare sector. Relative to sputum smear microscopy, use of IGRA for active TB resulted in 23,700 (95% uncertainty range, UR: 3,800 – 38,300) additional true-positive diagnoses, but at the expense of 315,700 (95% UR: 118,300 – 388,400) additional false-positive diagnoses and an incremental cost of US$49.3 million (95% UR: $34.9 – $58.0 million) (2.9 billion Indian Rupees). Relative to Xpert MTB/RIF (including the cost of treatment for drug resistant TB), use of IGRA led to 400 additional TB cases treated (95% UR: [-8,000] – 16,200), 370,600 (95% UR: 252,200 – 441,700) more false-positive diagnoses, 70,400 (95% UR: [-7,900] – 247,200) fewer disability-adjusted life years averted, and US$14.6 million (95%UR: [-$7.2] – $28.7 million) (854 million Indian Rupees) in additional costs. Conclusion Using IGRAs for diagnosis of active TB in a setting like India results in tremendous overtreatment of people without TB, and substantial incremental cost with little gain in health. These results support the policies by WHO and Standards for TB Care in India, which discourage the use of
Keller, Peter M; Hömke, Rico; Ritter, Claudia; Valsesia, Giorgia; Bloemberg, Guido V; Böttger, Erik C
Bedaquiline (Sirturo) and delamanid (Deltyba) have recently been approved by the regulatory authorities for treatment of multidrug-resistant tuberculosis (MDR-TB). Antimicrobial susceptibility testing is not established for either substance. On the basis of the use of the MGIT 960 system equipped with EpiCenter/TB eXiST, we determined a mean bedaquiline MIC for wild-type strains of 0.65 mg/liter (median, 0.4 mg/liter) and an epidemiological cutoff (ECOFF) of 1.6 mg/liter; for delamanid, a mean wild-type drug MIC of 0.013 mg/liter (median, 0.01 mg/liter) and an ECOFF of 0.04 mg/liter were determined.
Suzukawa, Maho; Akashi, Shunsuke; Nagai, Hideaki; Nagase, Hiroyuki; Nakamura, Hiroyuki; Matsui, Hirotoshi; Hebisawa, Akira; Ohta, Ken
The QuantiFERON®-TB Gold In-Tube test (QFT), an interferon-γ release assay, is used to diagnose Mycobacterium tuberculosis, but its inaccuracy in distinguishing active tuberculosis from latent infection is a major concern. There is thus a need for an easy and accurate tool for achieving that goal in daily clinical settings. This study aimed to identify candidate cytokines for specifically differentiating active tuberculosis from latent infection. Our study population consisted of 31 active TB (tuberculosis) patients, 29 LTBI (latent tuberculosis infection) patients and 10 healthy control subjects. We assayed for 27 cytokines in QFT supernatants of both specific antigen-stimulated blood samples (TBAg) and negative-control samples (Nil). We analyzed their specificities and sensitivities by creating receiver operating characteristic (ROC) curves and measuring the area under those curves (AUCs). In TBAg-Nil supernatants, IL-10, IFN-γ, MCP-1 and IL-1RA showed high AUCs of 0.8120, 0.7842, 0.7419 and 0.7375, respectively. Compared with each cytokine alone, combined assay for these top four cytokines showed positive rates in diagnosing active TB, and GDA analysis revealed that MCP-1 and IL-5 are potent in distinguishing active TB from LTBI, with Wilk's lambda = 0.718 (p < 0.001). Furthermore, utilizing the unique characteristic of IL-2 that its TBAg-Nil supernatant levels are higher in LTBI compared to active TB, the difference between IFN-γ and IL-2 showed a large AUC of 0.8910. In summary, besides IFN-γ, IL-2, IL-5, IL-10, IL-1RA and MCP-1 in QFT supernatants may be useful for distinguishing active TB from LTBI. Those cytokines may also help us understand the difference in pathogenesis between active TB and LTBI.
Shen, Lei; Shi, Hong; Gao, Yan; Ou, Qinfang; Liu, Qianqian; Liu, Yuanyuan; Wu, Jing; Zhang, Wenhong; Fan, Lin; Shao, Lingyun
PD-1 is a cell surface receptor of activated T and B lymphocytes and it's role in tuberculosis is controversial because of lack of congruence between clinical study and animal model. To investigate the immunological pathogenesis mechanisms of tuberculosis and to develop the immune therapy target essential for controlling tuberculosis, here we explored the expression characteristics and dynamic changes of PD-1/PD-L1 pathway in different CD4+T cell subsets. We enrolled 24 human subjects including 15 active tuberculosis (ATB) patients and 9 healthy donors (HD). The expressions of PD-1 and PD-L1 on CD4+T cells increased significantly in ATB patients than HD. ATB patients had a higher proportion of regulatory T cells (Treg, CD4(+)CD25 + Foxp3+) than HD. The expressions of PD-1 and PD-L1 increased remarkably on CD4+T cell subsets, including Treg cells, Tresp (CD4(+)CD25(-)) cells and Teff (CD4(+)CD25 + Foxp3-) cells. Finally, clinical improvement following effective anti-TB therapy is correlated with significantly decreased expression of PD-1 in Tresp and Teff cells, but not in Treg cells. Thus, expression profiles of PD-1 in T cell subpopulations may be used as a candidate to predict the clinical efficacy of anti-tuberculosis therapy. Modulation of PD-1/PD-L1 pathway in CD4 subsets may offer an immunotherapy target for the control of tuberculosis.
Natale, Jo Anna
The reemergence of tuberculosis, particularly of new drug-resistant strains, points up the need for well-coordinated school health programs. Immigration effects, growing populations of HIV-infected persons, and relaxed screening procedures are partly responsible for TB's reemergence. Two sidebars offer advice on coping with TB at school and…
Reddy, K K; Ananthakrishnan, R; Jacob, A G; Das, M; Isaakidis, P; Kumar, A M V
India mainly uses passive case finding to detect tuberculosis (TB) patients through the Revised National Tuberculosis Control Programme (RNTCP). An intensified case finding (ICF) intervention was conducted among vulnerable communities in two districts of Karnataka during July-December 2013; 658 sputum smear-positive TB cases were detected. The number of smear-positive cases detected increased by 8.8% relative to the pre-intervention period (July-December 2012) in intervention communities as compared to an 8.6% decrease in communities without the ICF intervention. ICF activities brought TB services closer to vulnerable communities, moderately increasing TB case detection rates.
Young, D; Kent, L; Rees, A; Lamb, J; Ivanyi, J
A 38-kilodalton (kDa) protein antigen from Mycobacterium tuberculosis was purified by monoclonal antibody TB71-based affinity chromatography. This molecule carries two nonoverlapping epitopes recognized by monoclonal antibodies TB71 and TB72, which are expressed substantially more strongly by M. tuberculosis than by Mycobacterium bovis. However, cross-reactive determinants between these two species were revealed on the 38-kDa protein by a rabbit anti-BCG serum. An immunoradiometric assay based on the TB71 and TB72 antibody pair specifically determined 38-kDa-antigen concentrations in mycobacterial extracts. Antibodies in sera from tuberculosis patients estimated by binding to 38-kDa-antigen-coated microtiter plates were positively correlated with TB72 competing titers. Unlike antibodies, T-cell proliferative responses to the 38-kDa protein were expressed equally by 60% of tuberculosis patients and healthy BCG-vaccinated subjects. Similarly, delayed-type hypersensitivity skin reactions were elicited in both M. tuberculosis- and M. bovis-sensitized guinea pigs. The results suggest the immunodominance of the species-specific B-cell and cross-reactive T-cell stimulatory epitopes. Images PMID:2428751
Belay, Mulugeta; Bjune, Gunnar; Abebe, Fekadu
Background TB-HIV co-infection is one of the biggest public health challenges in sub-Saharan Africa. Although there is a wealth of information on TB-HIV co-infection among settled populations in Africa and elsewhere, to our knowledge, there are no published reports on TB-HIV co-infection from pastoral communities. In this study, we report the prevalence of TB, HIV and TB-HIV co-infection among pulmonary TB suspects in the Afar Regional State of Ethiopia. Design In a cross-sectional study design, 325 pulmonary TB suspects were included from five health facilities. Three sputum samples (spot-morning-spot) were collected from each participant. Sputum samples were examined for the presence of acid fast bacilli using Ziehl–Neelsen staining method, and culture was done on the remaining sputum samples. Participants were interviewed and HIV tested. Results Of the 325 pulmonary TB suspects, 44 (13.5%) were smear positive, and 105 (32.3%) were culture positive. Among smear-positive patients, five were culture negative and, therefore, a total of 110 (33.8%) suspects were bacteriologically confirmed pulmonary TB patients. Out of 287 pulmonary TB suspects who were tested for HIV infection, 82 (28.6%) were HIV positive. A significantly higher proportion of bacteriologically confirmed pulmonary TB patients [40 (40.4%)] were HIV co-infected compared with patients without bacteriological evidence for pulmonary TB [42 (22.3%)]. However, among ethnic Afar pastoralists, HIV infections in smear- and/or culture-negative pulmonary TB suspects [7 (7.6%)] and bacteriologically confirmed pulmonary TB patients [4 (11.8%)] were comparable. On multivariable logistic regression analysis, Afar ethnicity was independently associated with low HIV infection [OR=0.16 (95% CI: 0.07–0.37)], whereas literacy was independently associated with higher HIV infection [OR=2.21 (95% CI: 1.05–4.64)]. Conclusions Although the overall prevalence of TB-HIV co-infection in the current study is high, ethnic
Shah, L; Rojas, M; Mori, O; Zamudio, C; Kaufman, J S; Otero, L; Gotuzzo, E; Seas, C; Brewer, T F
We compared the cost-effectiveness (CE) of an active case-finding (ACF) programme for household contacts of tuberculosis (TB) cases enrolled in first-line treatment to routine passive case-finding (PCF) within an established national TB programme in Peru. Decision analysis was used to model detection of TB in household contacts through: (1) self-report of symptomatic cases for evaluation (PCF), (2) a provider-initiated ACF programme, (3) addition of an Xpert MTB/RIF diagnostic test for a single sputum sample from household contacts, and (4) all strategies combined. CE was calculated as the incremental cost-effectiveness ratio (ICER) in terms of US dollars per disability-adjusted life years (DALYs) averted. Compared to PCF alone, ACF for household contacts resulted in an ICER of $2155 per DALY averted. The addition of the Xpert MTB/RIF diagnostic test resulted in an ICER of $3275 per DALY averted within a PCF programme and $3399 per DALY averted when an ACF programme was included. Provider-initiated ACF of household contacts in an urban setting of Lima, Peru can be highly cost-effective, even including costs to seek out contacts and perform an Xpert/MTB RIF test. ACF including Xpert MTB/RIF was not cost-effective if TB cases detected had high rates of default from treatment or poor outcomes.
Shehu, Amina I.; Li, Guangming; Xie, Wen; Ma, Xiaochao
Introduction Among the infectious diseases, tuberculosis (TB) remains the second cause of death after HIV. TB treatment requires the combination of multiple drugs including the rifamycin class. However, rifamycins are activators of human pregnane X receptor (PXR), a transcription factor that regulates drug metabolism, drug resistance, energy metabolism, and immune response. Rifamycin-mediated PXR activation may affect the outcome of TB therapy. Areas covered This review describes the role of PXR in modulating metabolism, efficacy, toxicity, and resistance to anti-TB drugs; as well as polymorphisms of PXR that potentially affect TB susceptibility. Expert opinion The wide range of PXR functions aside mediating drug metabolism and toxicity in TB therapy is underappreciated and thus understudied. Further studies are needed to determine the overall impact of PXR activation on the outcome of TB therapy. PMID:26592418
Burger, Divan Aristo; Schall, Robert
Trials of the early bactericidal activity (EBA) of tuberculosis (TB) treatments assess the decline, during the first few days to weeks of treatment, in colony forming unit (CFU) count of Mycobacterium tuberculosis in the sputum of patients with smear-microscopy-positive pulmonary TB. Profiles over time of CFU data have conventionally been modeled using linear, bilinear, or bi-exponential regression. We propose a new biphasic nonlinear regression model for CFU data that comprises linear and bilinear regression models as special cases and is more flexible than bi-exponential regression models. A Bayesian nonlinear mixed-effects (NLME) regression model is fitted jointly to the data of all patients from a trial, and statistical inference about the mean EBA of TB treatments is based on the Bayesian NLME regression model. The posterior predictive distribution of relevant slope parameters of the Bayesian NLME regression model provides insight into the nature of the EBA of TB treatments; specifically, the posterior predictive distribution allows one to judge whether treatments are associated with monolinear or bilinear decline of log(CFU) count, and whether CFU count initially decreases fast, followed by a slower rate of decrease, or vice versa. PMID:25322214
Differential cellular recognition pattern to M. tuberculosis targets defined by IFN-γ and IL-17 production in blood from TB + patients from Honduras as compared to health care workers: TB and immune responses in patients from Honduras
Background A better understanding of the quality of cellular immune responses directed against molecularly defined targets will guide the development of TB diagnostics and identification of molecularly defined, clinically relevant M.tb vaccine candidates. Methods Recombinant proteins (n = 8) and peptide pools (n = 14) from M. tuberculosis (M.tb) targets were used to compare cellular immune responses defined by IFN-γ and IL-17 production using a Whole Blood Assay (WBA) in a cohort of 148 individuals, i.e. patients with TB + (n = 38), TB- individuals with other pulmonary diseases (n = 81) and individuals exposed to TB without evidence of clinical TB (health care workers, n = 29). Results M.tb antigens Rv2958c (glycosyltransferase), Rv2962c (mycolyltransferase), Rv1886c (Ag85B), Rv3804c (Ag85A), and the PPE family member Rv3347c were frequently recognized, defined by IFN-γ production, in blood from healthy individuals exposed to M.tb (health care workers). A different recognition pattern was found for IL-17 production in blood from M.tb exposed individuals responding to TB10.4 (Rv0288), Ag85B (Rv1886c) and the PPE family members Rv0978c and Rv1917c. Conclusions The pattern of immune target recognition is different in regard to IFN-γ and IL-17 production to defined molecular M.tb targets in PBMCs from individuals frequently exposed to M.tb. The data represent the first mapping of cellular immune responses against M.tb targets in TB patients from Honduras. PMID:23497342
Measurement of Phenotype and Absolute Number of Circulating Heparin-Binding Hemagglutinin, ESAT-6 and CFP-10, and Purified Protein Derivative Antigen-Specific CD4 T Cells Can Discriminate Active from Latent Tuberculosis Infection
Barkham, Timothy M. S.; Tang, Wenying; Kemeny, David M.; Chee, Cynthia Bin-Eng; Wang, Yee T.
The tuberculin skin test (TST) and interferon gamma (IFN-γ) release assays (IGRAs) are used as adjunctive tests for the evaluation of suspected cases of active tuberculosis (TB). However, a positive test does not differentiate latent from active TB. We investigated whether flow cytometric measurement of novel combinations of intracellular cytokines and surface makers on CD4 T cells could differentiate between active and latent TB after stimulation with Mycobacterium tuberculosis-specific proteins. Blood samples from 60 patients referred to the Singapore Tuberculosis Control Unit for evaluation for active TB or as TB contacts were stimulated with purified protein derivative (PPD), ESAT-6 and CFP-10, or heparin-binding hemagglutinin (HBHA). The CD4 T cell cytokine response (IFN-γ, interleukin-2 [IL-2], interleukin-17A [IL-17A], interleukin-22 [IL-22], granulocyte-macrophage colony-stimulating factor [GM-CSF], and tumor necrosis factor alpha [TNF-α]) and surface marker expression (CD27, CXCR3, and CD154) were then measured. We found that the proportion of PPD-specific CD4 T cells, defined as CD154+ TNF-α+ cells that were negative for CD27 and positive for GM-CSF, gave the strongest discrimination between subjects with latent and those with active TB (area under the receiver operator characteristic [ROC] curve of 0.9277; P < 0.0001). Also, the proportions and absolute numbers of HBHA-specific CD4 T cells were significantly higher in those with latent TB infection, particularly CD154+ TNF-α+ IFN-γ+ IL-2+ and CD154+ TNF-α+ CXCR3+. Finally, we found that the ratio of ESAT-6- and CFP-10-responding to HBHA-responding CD4 T cells was significantly different between the two study populations. In conclusion, we found novel markers of M. tuberculosis-specific CD4 cells which differentiate between active and latent TB. PMID:25520147
... Tuberculosis; Proposed Rule; Termination of Rulemaking Respiratory Protection for M. Tuberculosis; Final Rule... Exposure to Tuberculosis AGENCY: Occupational Safety and Health Administration (OSHA), Labor. ACTION... Occupational Exposure to Tuberculosis (TB). Because of a broad range of Federal and community initiatives,...
Bermejo, A; Veeken, H; Berra, A
95% of tuberculosis (TB) cases in the world live in developing countries. HIV infection greatly increases the risk of developing active TB among those with latent Mycobacterium tuberculosis infection. Thus researchers have used data from existing research to develop a mathematical model to gauge the increase in TB incidence in developing countries while considering rising HIV prevalence among adults. They look at 2 groups with sizable differences in risk of acquiring TB: adults with both HIV and M. tuberculosis infections and all other adults. The researchers plot the expected increase in TB incidence and percentage of TB cases that also have HIV infection against HIV prevalence. According to the model, when the prevalence of HIV infection hits 13% of adults in developing countries, the number of new TB cases doubles. Most of this increase will occur in areas that already lack diagnostic services, drugs, hospital beds, and other needed supplies. TB chemoprophylaxis treatment of HIV-positive people could result in a lower increase in TB incidence, however. WHO has set a goal of 50% reduction in TB incidence by 2002. Public health officials could use this model to plan TB control programs to bring about a reduction in the increase. Even though TB control programs can help stem the projected increase, it will be very difficult for developing countries with high HIV prevalence to hold back the projected rise in TB incidence. Developing countries must take considerable appropriate action soon to prevent doubling of TB incidence as HIV prevalence nears 13% of adults.
Galli, Luisa; Lancella, Laura; Tersigni, Chiara; Venturini, Elisabetta; Chiappini, Elena; Bergamini, Barbara Maria; Codifava, Margherita; Venturelli, Cristina; Tosetti, Giulia; Marabotto, Caterina; Cursi, Laura; Boccuzzi, Elena; Garazzino, Silvia; Tovo, Pier Angelo; Pinon, Michele; Le Serre, Daniele; Castiglioni, Laura; Lo Vecchio, Andrea; Guarino, Alfredo; Bruzzese, Eugenia; Losurdo, Giuseppe; Castagnola, Elio; Bossi, Grazia; Marseglia, Gian Luigi; Esposito, Susanna; Bosis, Samantha; Grandolfo, Rita; Fiorito, Valentina; Valentini, Piero; Buonsenso, Danilo; Domenici, Raffaele; Montesanti, Marco; Salvini, Filippo Maria; Riva, Enrica; Dodi, Icilio; Maschio, Francesca; Abbagnato, Luisa; Fiumana, Elisa; Fornabaio, Chiara; Ballista, Patrizia; Portelli, Vincenzo; Bottone, Gabriella; Palladino, Nicola; Valenzise, Mariella; Vecchi, Barbara; Di Gangi, Maria; Lupi, Carla; Villani, Alberto; de Martino, Maurizio
Tuberculosis (TB) is one of the leading causes of death worldwide. Over the last decades, TB has also emerged in the pediatric population. Epidemiologic data of childhood TB are still limited and there is an urgent need of more data on very large cohorts. A multicenter study was conducted in 27 pediatric hospitals, pediatric wards, and public health centers in Italy using a standardized form, covering the period of time between 1 January 2010 and 31 December 2012. Children with active TB, latent TB, and those recently exposed to TB or recently adopted/immigrated from a high TB incidence country were enrolled. Overall, 4234 children were included; 554 (13.1%) children had active TB, 594 (14.0%) latent TB and 3086 (72.9%) were uninfected. Among children with active TB, 481 (86.8%) patients had pulmonary TB. The treatment of active TB cases was known for 96.4% (n = 534) of the cases. Overall, 210 (39.3%) out of these 534 children were treated with three and 216 (40.4%) with four first-line drugs. Second-line drugs where used in 87 (16.3%) children with active TB. Drug-resistant strains of Mycobacterium tuberculosis were reported in 39 (7%) children. Improving the surveillance of childhood TB is important for public health care workers and pediatricians. A non-negligible proportion of children had drug-resistant TB and was treated with second-line drugs, most of which are off-label in the pediatric age. Future efforts should concentrate on improving active surveillance, diagnostic tools, and the availability of antitubercular pediatric formulations, also in low-endemic countries.
Galli, Luisa; Lancella, Laura; Tersigni, Chiara; Venturini, Elisabetta; Chiappini, Elena; Bergamini, Barbara Maria; Codifava, Margherita; Venturelli, Cristina; Tosetti, Giulia; Marabotto, Caterina; Cursi, Laura; Boccuzzi, Elena; Garazzino, Silvia; Tovo, Pier Angelo; Pinon, Michele; Le Serre, Daniele; Castiglioni, Laura; Lo Vecchio, Andrea; Guarino, Alfredo; Bruzzese, Eugenia; Losurdo, Giuseppe; Castagnola, Elio; Bossi, Grazia; Marseglia, Gian Luigi; Esposito, Susanna; Bosis, Samantha; Grandolfo, Rita; Fiorito, Valentina; Valentini, Piero; Buonsenso, Danilo; Domenici, Raffaele; Montesanti, Marco; Salvini, Filippo Maria; Riva, Enrica; Dodi, Icilio; Maschio, Francesca; Abbagnato, Luisa; Fiumana, Elisa; Fornabaio, Chiara; Ballista, Patrizia; Portelli, Vincenzo; Bottone, Gabriella; Palladino, Nicola; Valenzise, Mariella; Vecchi, Barbara; Di Gangi, Maria; Lupi, Carla; Villani, Alberto; de Martino, Maurizio
Tuberculosis (TB) is one of the leading causes of death worldwide. Over the last decades, TB has also emerged in the pediatric population. Epidemiologic data of childhood TB are still limited and there is an urgent need of more data on very large cohorts. A multicenter study was conducted in 27 pediatric hospitals, pediatric wards, and public health centers in Italy using a standardized form, covering the period of time between 1 January 2010 and 31 December 2012. Children with active TB, latent TB, and those recently exposed to TB or recently adopted/immigrated from a high TB incidence country were enrolled. Overall, 4234 children were included; 554 (13.1%) children had active TB, 594 (14.0%) latent TB and 3086 (72.9%) were uninfected. Among children with active TB, 481 (86.8%) patients had pulmonary TB. The treatment of active TB cases was known for 96.4% (n = 534) of the cases. Overall, 210 (39.3%) out of these 534 children were treated with three and 216 (40.4%) with four first-line drugs. Second-line drugs where used in 87 (16.3%) children with active TB. Drug-resistant strains of Mycobacterium tuberculosis were reported in 39 (7%) children. Improving the surveillance of childhood TB is important for public health care workers and pediatricians. A non-negligible proportion of children had drug-resistant TB and was treated with second-line drugs, most of which are off-label in the pediatric age. Future efforts should concentrate on improving active surveillance, diagnostic tools, and the availability of antitubercular pediatric formulations, also in low-endemic countries. PMID:27322255
Trnka, L; Danková, D; Krejbich, F; Svandová, E
Report is given on the tuberculosis (TB) prevalence and the new diseases monitoring in Czech Republic (CR) in 1999 using the register of notifiable TB diseases. 1631 new TB cases and relapse were notified (15.9/100,000 citizens). Majority TB cases, 1369 (13.3/100,000 citizens) were of the respiratory system and 262 TB cases were in other locations. 63% of the respiratory system diseases were bacteriologically verified. In comparison with the year 1998, the number of newly notified TB patients was 9.6% lower, number of TB cases of the respiratory system which were bacteriologically verified was 12.3% lower, cases of microscopically positive TB were 17.4% less frequent. Among the notified TB patients there were 91 foreigners. TB relapse was identified in 61 patients. Among the notified TB cases, 987 (60.5%) were males and 644 (39.5%) were females. In both sexes patients over 65 predominated. Prevalence of TB cases higher than the average for the whole state was found in Prague, northern and western Bohemia. Groups with TB prevalence higher than 50/100,000 citizens were identified (the risk groups). They include homeless people, drug addicts, asylum applicants, and prisoners. Due to subjective troubles of patients TB was diagnosed in 70.2% cases, by active investigation in 13.9% patients. Late TB diagnosis at autopsy came in 6.8% cases. Decease due to TB was notified in 79 patients. In 77 of them TB had not been diagnosed premortally. 106 new cases and relapses of non-TB mycobacterial disease were notified in 1999. The case of tuberculosis in CR was in 1999 restrainable. In comparison with 1998 significant decrease of TB prevalence in individual subgroups of TB disease was described (10 to 17%). Also the decrease of the long-term trend (10 years) of newly notified TB patients and TB of the respiratory system was depicted. It is necessary to maintain the quality and extend of the TB control program in order to prevent the new outbreak of TB disease.
Bowong, Samuel; Aziz Alaoui, A. M.
This paper deals with the problem of optimal control of a deterministic model of tuberculosis (abbreviated as TB for tubercle bacillus). We first present and analyze an uncontrolled tuberculosis model which incorporates the essential biological and epidemiological features of the disease. The model is shown to exhibit the phenomenon of backward bifurcation, where a stable disease-free equilibrium co-exists with one or more stable endemic equilibria when the associated basic reproduction number is less than the unity. Based on this continuous model, the tuberculosis control is formulated and solved as an optimal control problem, indicating how control terms on the chemoprophylaxis and detection should be introduced in the population to reduce the number of individuals with active TB. Results provide a framework for designing the cost-effective strategies for TB with two intervention methods.
Jenkins, Helen E.
In 2015, the World Health Organization (WHO) declared tuberculosis (TB) to be responsible for more deaths than any other single infectious disease. The burden of TB among children has frequently been dismissed as relatively low with resulting deaths contributing very little to global under-five all-cause mortality, although without rigorous estimates of these statistics, the burden of childhood TB was, in reality, unknown. Recent work in the area has resulted in a WHO estimate of 1 million new cases of childhood TB in 2014 resulting in 136,000 deaths. Around 3% of these cases likely have multidrug-resistant TB and at least 40,000 are in HIV-infected children. TB is now thought to be a major or contributory cause of many deaths in children under five years old, despite not being recorded as such, and is likely in the top ten causes of global mortality in this age group. In particular, recent work has shown that TB is an under-lying cause of a substantial proportion of pneumonia deaths in TB-endemic countries. Childhood TB should be given higher priority: we need to identify children at greatest risk of TB disease and death and make more use of tools such as active case-finding and preventive therapy. TB is a preventable and treatable disease from which no child should die. PMID:28003956
Zeng, Jin-Cheng; Lin, Dong-Zi; Yi, Lai-Long; Liu, Gan-Bin; Zhang, Hui; Wang, Wan-Dang; Zhang, Jun-Ai; Wu, Xian-Jing; Xiang, Wen-Yu; Kong, Bin; Chen, Zheng W; Wang, Cong-Yi; Xu, Jun-Fa
Despite past extensive studies, the role of B and T lymphocyte attenuator (BTLA) in αβ T cells in patients with active pulmonary tuberculosis (ATB) remains poorly understood. Here we demonstrate that BTLA expression on αβ T cells is decreased in patients with M. tuberculosis (Mtb) infection. Particularly, BTLA expression levels are likely critical for αβ T cells to manifest and maintain an active central memory phenotype with high capacity for secretion of IFN-γ and perforin, which are important for immune memory against TB infection. BTLAhigh αβ T cells also exhibited higher capacity in response to Mtb peptide stimulation. In contrast to the role of BTLA played for negative regulation of immune responses, our data in the current studies suggest that BTLA expression on αβ T cells is likely associated with protective immune memory against Mtb infection in the setting of patients with active pulmonary tuberculosis. This previous unappreciated role for BTLA may have implications for prevention and treatment of patients with Mtb infection. PMID:25360214
Dutta, Noton K.; He, Rongjun; Pinn, Michael L.; He, Yantao; Burrows, Francis; Zhang, Zhong-Yin; Karakousis, Petros C.
Novel drugs are required to shorten the duration of treatment for tuberculosis (TB) and to combat the emergence of drug resistance. One approach has been to identify and target Mycobacterium tuberculosis (Mtb) virulence factors, which promote the establishment of TB infection and pathogenesis. Mtb produces a number of virulence factors, including two protein tyrosine phosphatases (PTPs), mPTPA and mPTPB, to evade the antimicrobial functions of host macrophages. To assess the therapeutic potential of targeting the virulent Mtb PTPs, we developed highly potent and selective inhibitors of mPTPA (L335-M34) and mPTPB (L01-Z08) with drug-like properties. We tested the bactericidal activity of L335-M34 and L01-Z08 alone or together in combination with the standard antitubercular regimen of isoniazid-rifampicin-pyrazinamide (HRZ) in the guinea pig model of chronic TB infection, which faithfully recapitulates some of the key histological features of human TB lesions. Following a single dose of L335-M34 50mg/kg and L01-Z08 20 mg/kg, plasma levels were maintained at levels 10-fold greater than the biochemical IC50 for 12–24 hours. Although neither PTP inhibitor alone significantly enhanced the antibacterial activity of HRZ, dual inhibition of mPTPA and mPTPB in combination with HRZ showed modest synergy, even after 2 weeks of treatment. After 6 weeks of treatment, the degree of lung inflammation correlated with the bactericidal activity of each drug regimen. This study highlights the potential utility of targeting Mtb virulence factors, and specifically the Mtb PTPs, as a strategy for enhancing the activity of standard anti-TB treatment. PMID:27478867
Early, Julie V.; Casey, Allen; Martinez-Grau, Maria Angeles; Gonzalez Valcarcel, Isabel C.; Vieth, Michal; Ollinger, Juliane; Bailey, Mai Ann; Alling, Torey; Files, Megan; Ovechkina, Yulia
Mycobacterium tuberculosis is a global pathogen of huge importance which can adapt to several host niche environments in which carbon source availability is likely to vary. We developed and ran a phenotypic screen using butyrate as the sole carbon source to be more reflective of the host lung environment. We screened a library of ∼87,000 small compounds and identified compounds which demonstrated good antitubercular activity against M. tuberculosis grown with butyrate but not with glucose as the carbon source. Among the hits, we identified an oxadiazole series (six compounds) which had specific activity against M. tuberculosis but which lacked cytotoxicity against mammalian cells. PMID:27044545
Vallada, Marcelo Genofre; Okay, Thelma Suely; Del Negro, Gilda Maria B.; Antonio, Claudio Amaral; Yamamoto, Lidia; Ramos, Sonia Regina T. S.
Objective: To evaluate the accuracy of an interferongamma release assay (QuantiFERON-TB Gold in Tube) for diagnosing Mycobacterium tuberculosis infection in a young pediatric population. Methods: 195 children previously vaccinated with BCG were evaluated, being 184 healthy individuals with no clinical or epidemiological evidence of mycobacterial infection, and 11 with Mycobacterium tuberculosis infection, according to clinical, radiological, and laboratory parameters. A blood sample was obtained from each child and processed according to the manufacturer's instructions. The assay performance was evaluated by a Receiver Operating Characteristic (ROC) curve. Results: In the group of 184 non-infected children, 130 (70.6%) were under the age of four years (mean age of 35 months). In this group, 177 children (96.2%) had negative test results, six (3.2%) had indeterminate results, and one (0.5%) had a positive result. In the group of 11 infected children, the mean age was 58.5 months, and two of them (18%) had negative results. The ROC curve had an area under the curve of 0.88 (95%CI 0.82-0.92; p<0.001), disclosing a predictive positive value of 81.8% for the test (95%CI 46.3-97.4). The assay sensitivity was 81.8% (95%CI 48.2-97.2) and the specificity was 98.8% (95%CI 96-99.8). Conclusions: In the present study, the QuantiFERON-TB Gold in Tube performance for diagnosing M. tuberculosis infection was appropriate in a young pediatric population. PMID:24676183
Tiruveedhula, V.V.N. Phani Babu; Witzigmann, Christopher M.; Verma, Ranjit; Kabir, M. Shahjahan; Rott, Marc; Schwan, William R.; Medina-Bielski, Sara; Lane, Michelle; Close, William; Polanowski, Rebecca L.; Sherman, David; Monte, Aaron; Deschamps, Jeffrey R.; Cook, James M.
The alarming increase in bacterial resistance over the last decade along with a dramatic decrease in new treatments for infections has led to problems in the healthcare industry. Tuberculosis (TB) is caused mainly by Mycobacterium tuberculosis which is responsible for 1.4 million deaths per year. A world-wide threat with HIV co-infected with multi and extensively drug-resistant strains of TB has emerged. In this regard, herein, novel acrylic acid ethyl ester derivatives were synthesized in simple, efficient routes and evaluated as potential agents against several Mycobacterium species. These were synthesized via a stereospecific process for structure activity relationship (SAR) studies. Minimum inhibitory concentration (MIC) assays indicated that esters 12, 13, and 20 exhibited greater in vitro activity against Mycobacterium smegmatis than rifampin, one of the current, first-line anti-mycobacterial chemotherapeutic agents. Based on these studies the acrylic ester 20 has been developed as a potential lead compound which was found to have an MIC value of 0.4 μg/mL against Mycobacterium tuberculosis. The SAR and biological activity of this series is presented; a Michael – acceptor mechanism appears to be important for potent activity of this series of analogs. PMID:24200931
Sánchez, María D; García, Yoenis; Montes, Carlos; París, Sara C; Rojas, Mauricio; Barrera, Luis F; Arias, Mauricio A; García, Luis F
Alterations of monocyte/macrophages have been reported in patients with tuberculosis (TB), but their significance is poorly understood. Blood mononuclear cells from patients with different clinical forms of TB, at various times of anti-TB treatment, and healthy tuberculin positive individuals, were double-stained for CD14 plus CD206, TLR-2, IFN-gammaR1, CD40, HLA-DR, CD36 and CD163, and analyzed by flow cytometry. Monocytes were infected with Mycobacterium tuberculosis H37Rv and 24h later the phenotype, induction of necrosis and apoptosis and production of tumor necrosis factor TNFalpha, interleukin (IL)-10 and IL-12p40 were determined. TB patients presented higher percentage of CD14+ cells but lower percentage of CD14+DR+ and CD14+CD36+ cells. Expression of CD14, HLA-DR and CD36 was decreased in TB patients. Normal percentages and expression were restored during anti-TB treatment. Monocytes from TB patients underwent necrosis and apoptosis after M. tuberculosis infection, whereas monocytes from healthy controls exhibited only apoptosis. Anti-TB treatment reverted necrosis. There were no differences between the various clinical forms of TB. In vitro M. tuberculosis infection decreased expression of the membrane molecules studied. HLA-DR and CD36 inhibition correlated with induction of apoptosis. Restoration of monocyte alterations during anti-TB treatment suggests that such alterations may be caused by the high M. tuberculosis load present during active disease.
Liu, Xueting; Chen, Caixia; He, Wenni; Huang, Pei; Liu, Miaomiao; Wang, Qian; Guo, Hui; Bolla, Krishna; Lu, Yan; Song, Fuhang; Dai, Huanqin; Liu, Mei; Zhang, Lixin
Multidrug-resistant tuberculosis (MDR-TB) and TB-HIV co-infection have become a great threat to global health. However, the last truly novel drug that was approved for the treatment of TB was discovered 40 years ago. The search for new effective drugs against TB has never been more intensive. Natural products derived from microbes and medicinal plants have been an important source of TB therapeutics. Recent advances have been made to accelerate the discovery rate of novel TB drugs including diversifying strategies for environmental strains, high-throughput screening (HTS) assays, and chemical diversity. This review will discuss the challenges of finding novel natural products with anti-TB activity from marine microbes and plant medicines, including biodiversity- and taxonomy-guided microbial natural products library construction, target- and cell-based HTS, and bioassay-directed isolation of anti-TB substances from traditional medicines.
Bates, Matthew; Ahmed, Yusuf; Kapata, Nathan; Maeurer, Markus; Mwaba, Peter; Zumla, Alimuddin
Tuberculosis (TB) has been recognized as an important cause of morbidity and mortality in pregnancy for nearly a century, but research and efforts to roll out comprehensive TB screening and treatment in high-risk populations such as those with a high prevalence of HIV or other diseases of poverty, have lagged behind similar efforts to address HIV infection in pregnancy and the prevention of mother-to-child-transmission. Immunological changes during pregnancy make the activation of latent TB infection or de novo infection more likely than among non-pregnant women. TB treatment in pregnancy poses several problems that have been under-researched, such as contraindications to anti-TB and anti-HIV drugs and potential risks to the neonate, which are particularly important with respect to second-line TB treatment. Whilst congenital TB is thought to be rare, data from high HIV burden settings suggest this is not the case. There is a need for more studies screening for TB in neonates and observing outcomes, and testing preventative or curative actions. National tuberculosis control programmes (NTPs) should work with antenatal and national HIV programmes in high-burden populations to provide screening at antenatal clinics, or to establish functioning systems whereby pregnant women at high risk can drop in to routine NTP screening stations.
Alemán, Mercedes; Schierloh, Pablo; de la Barrera, Silvia S; Musella, Rosa M; Saab, María A; Baldini, Matías; Abbate, Eduardo; Sasiain, María C
Polymorphonuclear neutrophils (PMN) exposed to Mycobacterium tuberculosis display bactericidal responses and produce inflammatory proteins. This PMN-mediated inflammatory response is regulated by an activation of the apoptotic program, which collaborates to avoid tissue injury. In vitro, circulating PMN from patients with tuberculosis (TB) show an increased spontaneous apoptosis, and M. tuberculosis-induced activation accelerates the PMN apoptosis. In this study, we evaluated the mechanisms involved in spontaneous and M. tuberculosis-induced apoptosis. We demonstrate that apoptosis of PMN is not induced by lipoarabinomannan or by a whole-cell lysate of M. tuberculosis and that neither tumor necrosis factor alpha nor CD11b, CD14, and Fcgamma receptors are involved. Apoptosis of PMN from patients with active TB (TB-PMN) is induced by the interaction with the whole M. tuberculosis via Toll-like receptor 2 (TLR2), and, in contrast to spontaneous apoptosis, it involves the p38 mitogen-activated protein kinase (MAPK) pathway. These results correlate with a high expression of phosphorylated p38 (p-p38) in circulating TB-PMN and with the ability of M. tuberculosis to induce in vitro the expression of p-p38 in PMN. Therefore, when the bacterial burden is low, TB-PMN could be detecting nonopsonized M. tuberculosis via TLR2, leading to the activation of the p38 MAPK pathway, which in turn would induce PMN activation and apoptosis. This mechanism needs further confirmation at the site of infection.
P, Shahul Hameed; Mukherjee, Kakoli; Nandi, Vrinda; Waterson, David; Shandil, Radha; Balganesh, Meenakshi; Sambandamurthy, Vasan K.; Raichurkar, Anand Kumar; Deshpande, Abhijeet; Ghosh, Anirban; Awasthy, Disha; Shanbhag, Gajanan; Sheikh, Gulebahar; McMiken, Helen; Puttur, Jayashree; Reddy, Jitendar; Werngren, Jim; Read, Jon; Kumar, Mahesh; R, Manjunatha; Chinnapattu, Murugan; Madhavapeddi, Prashanti; Manjrekar, Praveena; Basu, Reetobrata; Gaonkar, Sheshagiri; Sharma, Sreevalli; Hoffner, Sven; Humnabadkar, Vaishali; Subbulakshmi, Venkita; Panduga, Vijender
Moxifloxacin has shown excellent activity against drug-sensitive as well as drug-resistant tuberculosis (TB), thus confirming DNA gyrase as a clinically validated target for discovering novel anti-TB agents. We have identified novel inhibitors in the pyrrolamide class which kill Mycobacterium tuberculosis through inhibition of ATPase activity catalyzed by the GyrB domain of DNA gyrase. A homology model of the M. tuberculosis H37Rv GyrB domain was used for deciphering the structure-activity relationship and binding interactions of inhibitors with mycobacterial GyrB enzyme. Proposed binding interactions were later confirmed through cocrystal structure studies with the Mycobacterium smegmatis GyrB ATPase domain. The most potent compound in this series inhibited supercoiling activity of DNA gyrase with a 50% inhibitory concentration (IC50) of <5 nM, an MIC of 0.03 μg/ml against M. tuberculosis H37Rv, and an MIC90 of <0.25 μg/ml against 99 drug-resistant clinical isolates of M. tuberculosis. The frequency of isolating spontaneous resistant mutants was ∼10−6 to 10−8, and the point mutation mapped to the M. tuberculosis GyrB domain (Ser208 Ala), thus confirming its mode of action. The best compound tested for in vivo efficacy in the mouse model showed a 1.1-log reduction in lung CFU in the acute model and a 0.7-log reduction in the chronic model. This class of GyrB inhibitors could be developed as novel anti-TB agents. PMID:24126580
Ben-Selma, Walid; Boukadida, Jalel
The purpose of our study was to investigate the association between a functional single nucleotide polymorphism (SNP) in the interleukin-23 receptor gene (IL23R; rs11209026, 1142 G(wild type) → A(reduced function), Arg381Gln) and disease severity outcome in pulmonary tuberculosis (TB) in the Tunisian population. SNP was investigated in a population of 168 patients with active pulmonary TB (cases were stratified into patients with minimal/moderate lung involvement, i.e., patients with minimal/moderate disease [Pmd], and patients with extensive lung involvement, i.e., patients with active disease [Pad]) and 150 healthy subjects. Genotype analyses were carried out using the PCR-restriction fragment length polymorphism method. We have found that the IL23R reduced-function allele 1142A and genotypes AA and AG were overrepresented, especially in the Pad subgroup compared with the control group (51% versus 18% [P = 10(-8)], 33% versus 5% [P = 10(-8)], and 36% versus 26% [P = 5 × 10(-3)], respectively). Additionally, comparison of the Pad and the Pmd groups showed that the A allele and AA genotype seemed to be associated with 2.79-fold (P = 4 × 10(-5)) and 7.74-fold (P = 10(-5)) increased risks of TB with minimal/moderate lung involvement, respectively. Our results demonstrate that the reduced-function polymorphism 1142G → A encoded by IL23R influences the outcome of disease severity of active pulmonary TB in Tunisian patients.
Garrido, Joseba M.; Aranaz, Alicia; Sevilla, Iker; Villar, Margarita; Boadella, Mariana; Galindo, Ruth C.; Pérez de la Lastra, José M.; Moreno-Cid, Juan A.; Fernández de Mera, Isabel G.; Alberdi, Pilar; Santos, Gracia; Ballesteros, Cristina; Lyashchenko, Konstantin P.; Minguijón, Esmeralda; Romero, Beatriz; de Juan, Lucía; Domínguez, Lucas; Juste, Ramón; Gortazar, Christian
Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar. PMID:24842853
Alvarez, Gonzalo G.; VanDyk, Deborah D.; Aaron, Shawn D.; Cameron, D. William; Davies, Naomi; Stephen, Natasha; Mallick, Ranjeeta; Momoli, Franco; Moreau, Katherine; Obed, Natan; Baikie, Maureen; Osborne, Geraldine
Background The incidence rate of active tuberculosis (TB) disease in the Canadian Territory of Nunavut has shown a rising trend over the past 10 years. In 2010 it was 60 times greater than the national incidence rate. The objective of the Taima (translates to “stop” in Inuktitut) TB study was to implement and evaluate a public health campaign to enhance existing TB prevention efforts in Nunavut. Methods A TB awareness campaign followed by a door-to-door screening campaign was carried out in Iqaluit, Nunavut. The aim of the campaign was to raise awareness about TB, and to provide in-home screening and treatment for people living in residential areas at high risk for TB. Screening was based on geographic location rather than on individual risk factors. Results During the general awareness campaign an increase in the number of people who requested TB testing at the local public health clinic was observed. However, this increase was not sustained following cessation of the awareness campaign. Targeted TB screening in high risk residential areas in Iqaluit resulted in 224 individuals having TSTs read, and detection of 42 previously unidentified cases of latent TB, (overall yield of 18.8% or number needed to screen = 5.3). These cases of latent TB infection (LTBI) were extra cases that had not been picked up by traditional screening practices (34% relative increase within the community). This resulted in a 33% relative increase in the completion of LTBI treatment within the community. The program directly and indirectly identified 5/17 new cases of active TB disease in Iqaluit during the study period (29.5% of all incident cases). Conclusions While contact tracing investigations remain a cornerstone of TB prevention, additional awareness, screening, and treatment programs like Taima TB may contribute to the successful control of TB in Aboriginal communities. PMID:25033320
Koyama, Sekiya; Sakaguchi, Nobuki; Hotta, Jyunnichi
Mycobacterium tuberculosis (M. tuberculosis) infects all organs in the body; however, lung infection is the primary lesion. The total number of infections is decreasing, but the percentage of infections in older people is rising. Because this disease is due to infection with M. tuberculosis, the diagnosis requires the presence of M. tuberculosis. Chest X-ray and CT are very powerful tools to suggest the presence of M. tuberculosis infection. Pathological examination of the tissues also shows the typical findings of M. tuberculosis infection; however, the presence of the bacterium was not proven in certain cases of M. tuberculosis infection, and especially in cases of latent infection. Recently, the whole-blood interferon--gamma test (QuantiFERON-TB, QFT) became more popular than the tuberculin skin test. It is reported that the specificity and sensitivity of QFT are similar to or better than the tuberculin skin test. However, it should be noted that QFT positive does not automatically lead to a diagnosis of active M. tuberculosis infection and that QFT is one of the supplementary tests in the diagnosis of M. tuberculosis infection. Currently, massive infection with M. tuberculosis is increasing. The precise responsible linkage in massive infection with M. tuberculosis needs DNA polymorphism analysis using variable numbers of tandem repeats (VNTR) or restricted fragment length polymorphism (RFLP).
Feruglio, S L; Tonby, K; Kvale, D; Dyrhol-Riise, A M
Biomarkers that can identify tuberculosis (TB) disease and serve as markers for efficient therapy are requested. We have studied T cell cytokine production [interferon (IFN)-γ, interleukin (IL)-2, tumour necrosis factor (TNF)-α] and degranulation (CD107a) as well as subsets of CD4(+) T regulatory cells (Tregs ) after in-vitro Mycobacterium tuberculosis (Mtb) antigen stimulation [early secretory antigenic target (ESAT)-6, culture filtrate protein (CFP)-10, antigen 85 (Ag85)] in 32 patients with active tuberculosis (TB) disease throughout 24 weeks of effective TB treatment. A significant decline in the fraction of Mtb-specific total IFN-γ and single IFN-γ-producing T cells was already observed after 2 weeks of treatment, whereas the pool of single IL-2(+) cells increased over time for both CD4(+) and CD8(+) T cells. The Treg subsets CD25(high) CD127(low) , CD25(high) CD147(++) and CD25(high) CD127(low) CD161(+) expanded significantly after Mtb antigen stimulation in vitro at all time-points, whereas the CD25(high) CD127(low) CD39(+) Tregs remained unchanged. The fraction of CD25(high) CD127(low) Tregs increased after 8 weeks of treatment. Thus, we revealed an opposing shift of Tregs and intracellular cytokine production during treatment. This may indicate that functional signatures of the CD4(+) and CD8(+) T cells can serve as immunological correlates of early curative host responses. Whether such signatures can be used as biomarkers in monitoring and follow-up of TB treatment needs to be explored further.
We report two series of novel cephalosporins that are bactericidal to Mycobacterium tuberculosis alone of the pathogens tested, which only kill M. tuberculosis when its replication is halted by conditions resembling those believed to pertain in the host, and whose bactericidal activity is not dependent upon or enhanced by clavulanate, a β-lactamase inhibitor. The two classes of cephalosporins bear an ester or alternatively an oxadiazole isostere at C-2 of the cephalosporin ring system, a position that is almost exclusively a carboxylic acid in clinically used agents in the class. Representatives of the series kill M. tuberculosis within macrophages without toxicity to the macrophages or other mammalian cells. PMID:27144688
Gonzalez-Curiel, Irma; Castañeda-Delgado, Julio; Lopez-Lopez, Nallely; Araujo, Zaida; Hernandez-Pando, Rogelio; Gandara-Jasso, Benjamin; Macias-Segura, Noe; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno
Tuberculosis (TB) is one of the most important infectious diseases, causing 1.8 million deaths annually worldwide. This problem has increased because of the association with human immmunodeficiency virus and diabetes mellitus type 2, mainly in developing countries. In the past few years it has been highlighted the significance of antimicrobial peptides in the immunopathogenesis of TB ex vivo and in experimental models studies. In this study we analyzed the expression of CAMP, DEFA1, DEFB4, and DEFB103A in patients with latent TB and progressive TB with and without comorbidity with diabetes mellitus type 2. Antimicrobial peptide gene expression increased during progressive TB, which could be used as a biomarker for reactivation. By contrast, patients with diabetes mellitus type 2 have lower antimicrobial peptides gene expression, suggesting that the lack of its proper production in these patients contribute to enhance the risk for TB reactivation.
Lee, Ji Yeon; Jung, Young Won; Jeong, Ina; Joh, Joon-Sung; Sim, Soo Yeon; Choi, Boram; Jee, Hyeon-Gun; Lim, Dong-Gyun
Tuberculosis remains a highly prevalent infectious disease worldwide. Identification of the immune parameters that differentiate active disease from latent infection will facilitate the development of efficient control measures as well as new diagnostic modalities for tuberculosis. Here, we investigated the cytokine production profiles of monocytes and CD4(+) T lymphocytes upon encountering mycobacterial antigens. In addition, cytokines and lipid mediators with immune-modulating activities were examined in plasma samples ex vivo. Comparison of these parameters in active tuberculosis patients and healthy subjects with latent infection revealed that, active tuberculosis was associated with diminished Th1-type cytokine secretion from CD4(+) T cells and less augmented inflammatory cytokine secretion from monocytes induced by IFN-γ than that in latent tuberculosis infection. In addition, a higher plasma concentration of lipoxin A4 and lower ratio of prostaglandin E2 to lipoxin A4 were observed in active cases than in latent infections. These findings have implications for preparing new therapeutic strategies and for differential diagnosis of the two types of tuberculosis infection.
Gama, Ntombenhle H; Elkhadir, Afag Y F; Gordhan, Bhavna G; Kana, Bavesh D; Darkwa, James; Meyer, Debra
Treatment of human immunodeficiency virus (HIV) is currently complicated by increased prevalence of co-infection with Mycobacterium tuberculosis. The development of drug candidates that offer the simultaneous management of HIV and tuberculosis (TB) would be of great benefit in the holistic treatment of HIV/AIDS, especially in sub-Saharan Africa which has the highest global prevalence of HIV-TB coinfection. Bis(diphenylphosphino)-2-pyridylpalladium(II) chloride (1), bis(diphenylphosphino)-2-pyridylplatinum(II) chloride (2), bis(diphenylphosphino)-2-ethylpyridylpalladium(II) chloride (3) and bis(diphenylphosphino)-2-ethylpyridylplatinum(II) (4) were investigated for the inhibition of HIV-1 through interactions with the viral protease. The complexes were subsequently assessed for biological potency against Mycobacterium tuberculosis H37Rv by determining the minimal inhibitory concentration (MIC) using broth microdilution. Complex (3) showed the most significant and competitive inhibition of HIV-1 protease (p = 0.014 at 100 µM). Further studies on its in vitro effects on whole virus showed reduced viral infectivity by over 80 % at 63 µM (p < 0.05). In addition, the complex inhibited the growth of Mycobacterium tuberculosis at an MIC of 5 µM and was non-toxic to host cells at all active concentrations (assessed by tetrazolium dye and real time cell electronic sensing). In vitro evidence is provided here for the possibility of utilizing a single metal-based compound for the treatment of HIV/AIDS and TB.
Sun, Qin; Wei, Wei; Sha, Wei
Interferon gamma release assays (IGRAs) could accurately diagnose Mycobacterium tuberculosis (M.tuberculosis) infection. However, these assays do not discriminate between latent tuberculosis infection (LTBI) and active tuberculosis disease (ATB). Here, a total of 177 subjects, including 65 patients with ATB, 43 subjects with LTBI, and 69 TB-uninfected controls (CON group) were enrolled. The concentration of IFN-γ, IP-10, and IL-2 was determined in peripheral blood mononuclear cells (PBMCs) after short-term (24h) or long-term (72h) stimulation with TB antigens including ESAT-6/CFP-10 (EC) and purified protein derivative (PPD).EC-stimulated IL-2 and gamma interferon-inducible protein 10 (IP-10) release (24h and 72h) showed a good diagnostic performance in distinguishing between TB-infected and TB-uninfected individuals, but failed to discriminate between ATB and LTBI. After 72h of incubation, the release of IL-2 was higher in LTBI patients after stimulation with EC and PPD. The PPD-stimulated IL-2/IFN-γ ratio after 72h incubation had the diagnostic potential to discriminate between ATB and LTBI, with a sensitivity of 90.8% and a specificity of 97.7%. In addition, these new biomarkers, combined with T-SPOT test in a two-step strategy, were validated with high levels of accuracy in a prospective clinical-based cohort. Collectively, the PPD-stimulated IL-2/IFN-γ ratio after long-term incubation may be an alternative diagnostic biomarker in distinguishing between active TB patients and subjects with latent infection. PMID:28033330
MacDougall, D S
About 2 billion people worldwide are infected with Mycobacterium tuberculosis, the causative agent of tuberculosis (TB). TB is the leading cause of premature death in less industrialized countries, and 8 million more people become infected every year. The World Health Organization (WHO) declared TB a global emergency in 1993 and launched a series of prevention and vaccination programs. In spite of effective drug therapy and a vaccine, tuberculosis remains a major public health problem. The TB and HIV epidemics are closely intertwined, and the risk of TB disease progression is 100 times greater in HIV-positive individuals. TB is the leading cause of death among HIV-infected people worldwide, and virologic evidence suggests that the host immune response to TB may enhance HIV replication and accelerate the progression of HIV infection. The interaction between the two diseases was the subject of a conference called TB & HIV: Applying Advances to the Clinic, Public Health, and the World. Charts and tables show reported TB cases in the U.S., trends in TB cases among foreign-born persons in the U.S., and the country of origin for foreign-born persons with TB in the U.S. Several poster sessions from the conference are summarized. Strategies for dealing with the TB epidemic are outlined.
Neyman, Edward G; Georgiades, Christos S; Fishman, Elliot K
Rising incidence of disseminated and extrapulmonary tuberculosis (TB), especially in immunocompromised hosts and patients with multi-drug-resistant tuberculosis, has resulted in an increase of unusual clinical and radiographic presentations of TB. With CT being a common part of emergency room (ER) evaluation of abdominal pain, it is imperative that radiologists be able to recognize abdominal presentations of TB. We discuss and illustrate typical and less common CT manifestations of tuberculosis in the abdomen to help ER radiologists in this task.
González-Salazar, F; Vargas-Villarreal, J; Garcialuna-Martínez, F J; Rivera, G; Moreno-Treviño, M G; Montfort-Gardeazabal, J M; Garcialuna-Martínez, E
Most people infected with Mycobacterium tuberculosis have an asymptomatic condition named latent tuberculosis. These people do not have bacilli in the corporal secretions and are hard to diagnose by conventional laboratory tests. Diagnosis of latent tuberculosis infection (LTBI) in México is based on the tuberculin skin test (TST). This test has disadvantages, principally because the vaccine containing the Bacille Calmette-Guérin (BCG) is applied to 99% of this population and causes false positive TST outcomes. Recently, interferon-gamma release assays (IGRA) have been demonstrated to be a good test to detect latent tuberculosis with equal or better sensitivity to TST and without interference from BCG. However, in México the IGRA are an uncommon test due to the higher cost compared to TST. The main objective of this work was demonstrate the potential utility of the Quantiferon TB(®) gold in tube (QTB(®)-GIT) test to detect latent TB in a population from northern México. Samples from 106 subjects with close contact, or without contact, with actively infected TB patients were tested to detect LTBI. Our results show a significant difference between individuals in close contact with active TB patients (39.7%) compared to those without contact (3.2%), p < 0.01. The concordance between TST and QTB(®)-GIT was poor (κ = 0.31). Our preliminary results show that the QTB(®)-GIT has better capacity than TST to detect latent tuberculosis infection.
Sgaragli, Giampietro; Frosini, Maria
The great progress of knowledge of both M. tuberculosis physiology and how human host and bacilli interact has provided fertile ground for improving diagnosis and cure of TB infection. Once M. tuberculosis has infected humans, it elaborates strategies for evading the risk to killing by the cells of the host immune system and by the anti-tuberculosis (anti-TB) agents employed to cure infection. These strategies give rise to a bacterial multidrug resistance (MDR) status. This stems firstly from genetic mutations targeting a constellation of drug-processing mechanisms that still need full identification, as drug efflux pumps and drug activating/ inactivating enzymes (genetic resistance). Secondly, from the bacterial adaptation to stressful environmental conditions by adopting a temporary dormancy state lasting for decades and characterized by indifference to anti-TB drugs (phenotypic resistance or tolerance). The clarification of the strategies elaborated for surviving by M. tuberculosis has brought to the identification in the last few years of a number of mycobacterial molecular targets worth to exploitation for the development of novel and powerful anti-TB drugs. These targets include drug-efflux pump systems, considered partly responsible for genetic multi-drug resistance, and several enzymes and pump systems, as well, that sustain the metabolic adaptations of M. tuberculosis in the host and give rise to its phenotypic drug resistance.
Valente, Ilaria C.; Norbis, Luca; Sotgiu, Giovanni; Bosu, Roberta; Ambrosi, Alessandro; Codecasa, Luigi R.; Goletti, Delia; Matteelli, Alberto; Ntinginya, Elias N.; Aloi, Francesco; Heinrich, Norbert; Reither, Klaus; Cirillo, Daniela M.
Several studies showed that assessing levels of specific circulating microRNAs (miRNAs) is a non-invasive, rapid, and accurate method for diagnosing diseases or detecting alterations in physiological conditions. We aimed to identify a serum miRNA signature to be used for the diagnosis of tuberculosis (TB). To account for variations due to the genetic makeup, we enrolled adults from two study settings in Europe and Africa. The following categories of subjects were considered: healthy (H), active pulmonary TB (PTB), active pulmonary TB, HIV co-infected (PTB/HIV), latent TB infection (LTBI), other pulmonary infections (OPI), and active extra-pulmonary TB (EPTB). Sera from 10 subjects of the same category were pooled and, after total RNA extraction, screened for miRNA levels by TaqMan low-density arrays. After identification of “relevant miRNAs”, we refined the serum miRNA signature discriminating between H and PTB on individual subjects. Signatures were analyzed for their diagnostic performances using a multivariate logistic model and a Relevance Vector Machine (RVM) model. A leave-one-out-cross-validation (LOOCV) approach was adopted for assessing how both models could perform in practice. The analysis on pooled specimens identified selected miRNAs as discriminatory for the categories analyzed. On individual serum samples, we showed that 15 miRNAs serve as signature for H and PTB categories with a diagnostic accuracy of 82% (CI 70.2–90.0), and 77% (CI 64.2–85.9) in a RVM and a logistic classification model, respectively. Considering the different ethnicity, by selecting the specific signature for the European group (10 miRNAs) the diagnostic accuracy increased up to 83% (CI 68.1–92.1), and 81% (65.0–90.3), respectively. The African-specific signature (12 miRNAs) increased the diagnostic accuracy up to 95% (CI 76.4–99.1), and 100% (83.9–100.0), respectively. Serum miRNA signatures represent an interesting source of biomarkers for TB disease with the
This article reports the topics discussed at the second annual meeting of the Global Tuberculosis Research Initiative (GTRI) held June 29 to July 1, 1999, in Casablanca, Morocco. The meeting hailed the inclusion of tuberculosis (TB) in the Training in Tropical Diseases (TDR) portfolio of diseases. GTRI brings together diverse partners, from bench researchers to TB control program personnel, with the dual goals of developing a sustainable agenda for TB research addressing the needs of TB-endemic communities and increasing the resource allocated for TB research. The infusion of TDR expertise in training, research, and product development was expected to give substantial momentum to the drive to develop and carry out a significant and practicable global TB research agenda. The lack of research capability in TB-endemic countries, especially among TB control personnel, was a major stumbling block to the execution of a TB research agenda, and among the topic discussed at the meeting, integration of TB into existing Research Capacity Strengthening efforts of TDR received special focus. In its formal recommendations from the meeting, GTRI welcomed the inclusion of TB into the TDR portfolio of diseases and recommended rapid expansion of TB research activities within TDR. The recommendations to the TDR are listed.
Kumar, Ajay M V; Singarajipura, Anil; Naik, Balaji; Guddemane, Deepak K; Patel, Yogesh; Shastri, Suresh; Kumar, Sunil; Deshmukh, Rajesh; Rewari, B B; Harries, Anthony David
For certain subgroups within people living with the human immunodeficiency virus (HIV) [active tuberculosis (TB), pregnant women, children <5years old, and serodiscordant couples], the World Health Organization recommends antiretroviral therapy (ART) irrespective of CD4 count. Another subgroup which has received increased attention is "HIV-infected presumptive TB patients without TB". In this study, we assess the proportion of HIV-infected presumptive TB patients eligible for ART in Karnataka State (population 60million), India. This was a cross-sectional analysis of data of HIV-infected presumptive TB patients diagnosed in May 2015 abstracted from national TB and HIV program records. Of 42,585 presumptive TB patients, 28,964 (68%) were tested for HIV and 2262 (8%) were HIV positive. Of the latter, 377 (17%) had active TB. Of 1885 "presumptive TB patients without active TB", 1100 (58%) were already receiving ART. Of the remaining 785 who were not receiving ART, 617 (79%) were assessed for ART eligibility and of those, 548 (89%) were eligible for ART. About 90% of "HIV-infected presumptive TB patients without TB" were eligible for ART. This evidence supports a public health approach of starting all "HIV-infected presumptive TB patients without TB" on ART irrespective of CD4 count in line with global thinking about 'test and treat'.
Morales, M M; Llopis, A; Ballester, M L; Sanjuan, L
We studied the incidence of TB and TB-AIDS in the area served by "La Fe" hospital in Valencia. We also studied the different evolution of the incidence of TB and TB-AIDS during the 1985-1989 period. We noticed the progressive increase of the incidence of TB in AIDS patients, while the incidence of TB without AIDS remained the same.
... Old Feeding Your 1- to 2-Year-Old Tuberculosis KidsHealth > For Parents > Tuberculosis A A A What's in this article? Signs ... When to You Call the Doctor en español Tuberculosis Tuberculosis (popularly known as "TB") is a disease ...
... Old Feeding Your 1- to 2-Year-Old Tuberculosis KidsHealth > For Parents > Tuberculosis Print A A A What's in this article? ... When to You Call the Doctor en español Tuberculosis Tuberculosis (popularly known as "TB") is a disease ...
Launois, Pascal; Drowart, Annie; Bourreau, Eliane; Couppie, Pierre; Farber, Claire-Michèle; Van Vooren, Jean-Paul; Huygen, Kris
The mycolyl transferase antigen 85 complex is a major secreted protein family from mycobacterial culture filtrate, demonstrating powerful T cell stimulatory properties in most HIV-negative, tuberculin-positive volunteers with latent M.tuberculosis infection and only weak responses in HIV-negative tuberculosis patients. Here, we have analyzed T cell reactivity against PPD and Ag85 in HIV-infected individuals, without or with clinical symptoms of tuberculosis, and in AIDS patients with disease caused by nontuberculous mycobacteria. Whereas responses to PPD were not significantly different in HIV-negative and HIV-positive tuberculin-positive volunteers, responses to Ag85 were significantly decreased in the HIV-positive (CDC-A and CDC-B) group. Tuberculosis patients demonstrated low T cell reactivity against Ag85, irrespective of HIV infection, and finally AIDS patients suffering from NTM infections were completely nonreactive to Ag85. A one-year follow-up of twelve HIV-positive tuberculin-positive individuals indicated a decreased reactivity against Ag85 in patients developing clinical tuberculosis, highlighting the protective potential of this antigen.
Lun, Shichun; Guo, Haidan; Onajole, Oluseye K.; Pieroni, Marco; Gunosewoyo, Hendra; Chen, Gang; Tipparaju, Suresh K.; Ammerman, Nicole C.; Kozikowski, Alan P.; Bishai, William R.
Responsible for nearly two million deaths each year, the infectious disease tuberculosis remains a serious global health challenge. The emergence of multidrug- and extensively drug-resistant strains of Mycobacterium tuberculosis confounds control efforts, and new drugs with novel molecular targets are desperately needed. Here we describe lead compounds, the indoleamides, with potent activity against both drug-susceptible and drug-resistant strains of M. tuberculosis by targeting the mycolic acid transporter MmpL3. We identify a single mutation in mmpL3 which confers high resistance to the indoleamide class while remaining susceptible to currently used first- and second-line tuberculosis drugs, indicating a lack of cross-resistance. Importantly, an indoleamide derivative exhibits dose-dependent anti-mycobacterial activity when orally administered to M. tuberculosis-infected mice. The bioavailability of the indoleamides, combined with their ability to kill tubercle bacilli, indicates great potential for translational developments of this structure class for the treatment of drug-resistant tuberculosis. PMID:24352433
Cho, Won-Hyung; Won, Eun-Jeong; Choi, Hyun-Jung; Kee, Seung-Jung; Shin, Jong-Hee; Ryang, Dong-Wook; Suh, Soon-Pal
The AdvanSure tuberculosis/non-tuberculous mycobacterium (TB/NTM) PCR (LG Life Science, Korea) and COBAS TaqMan Mycobacterium tuberculosis (MTB) PCR (Roche Diagnostics, USA) are commonly used in clinical microbiology laboratories. We aimed to evaluate these two commercial real-time PCR assays for detection of MTB in a large set of clinical samples over a two-year period. AdvanSure TB/NTM PCR and COBAS TaqMan MTB PCR were performed on 9,119 (75.2%) and 3,010 (24.8%) of 12,129 (9,728 respiratory and 2,401 non-respiratory) MTB specimens, with 361 (4.0%) and 102 (3.4%) acid-fast bacilli (AFB)-positive results, respectively. In MTB culture, 788 (6.5%) MTB and 514 (4.2%) NTM were identified. The total sensitivity and specificity of the AdvanSure assay were 67.8% (95% confidence interval [CI], 63.9-71.6) and 98.3% (95% CI, 98.0-98.6), while those of the COBAS TaqMan assay were 67.2% (95% CI, 60.0-73.8) and 98.4% (95% CI, 97.9-98.9), respectively. The sensitivities and specificities of the AdvanSure and COBAS TaqMan assays for AFB-positive and AFB-negative samples were comparable. Furthermore, the AdvanSure assay showed fewer invalid results compared with the COBAS TaqMan assay (5.0 vs. 20.4 invalid results/1,000 tests, P<0.001). AdvanSure assay represents a comparable yet more reliable method than COBAS TaqMan for the identification of mycobacteria in routine clinical microbiology.
Preliminary structure-activity relationships and biological evaluation of novel antitubercular indolecarboxamide derivatives against drug-susceptible and drug-resistant Mycobacterium tuberculosis strains.
Onajole, Oluseye K; Pieroni, Marco; Tipparaju, Suresh K; Lun, Shichun; Stec, Jozef; Chen, Gang; Gunosewoyo, Hendra; Guo, Haidan; Ammerman, Nicole C; Bishai, William R; Kozikowski, Alan P
Tuberculosis (TB) remains one of the leading causes of mortality and morbidity worldwide, with approximately one-third of the world's population infected with latent TB. This is further aggravated by HIV coinfection and the emergence of multidrug- and extensively drug-resistant (MDR and XDR, respectively) TB; hence the quest for highly effective antitubercular drugs with novel modes of action is imperative. We report herein the discovery of an indole-2-carboxamide analogue, 3, as a highly potent antitubercular agent, and the subsequent chemical modifications aimed at establishing a preliminary body of structure-activity relationships (SARs). These efforts led to the identification of three molecules (12-14) possessing an exceptional activity in the low nanomolar range against actively replicating Mycobacterium tuberculosis , with minimum inhibitory concentration (MIC) values lower than those of the most prominent antitubercular agents currently in use. These compounds were also devoid of apparent toxicity to Vero cells. Importantly, compound 12 was found to be active against the tested XDR-TB strains and orally active in the serum inhibition titration assay.
Moon, S M; Lee, S-O; Choi, S-H; Kim, Y S; Woo, J H; Yoon, D H; Suh, C; Kim, D-Y; Lee, J-H; Lee, Je-H; Lee, K-H; Kim, S-H
A total of 244 patients including 100 (41%) autologous hematopoietic stem cell transplant (HCT) recipients and 144 (59%) allogeneic HCT recipients were enrolled over a 28-month period. During the study period, no prophylaxis for latent tuberculosis (TB) infection was administrated. Of these, 201 (82%) had Bacillus Calmette-Guérin (BCG) scars or prior histories of BCG vaccination. The tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube (QFT-GIT) test were performed simultaneously in all 244 patients. TST indurations were ≥ 5 mm in 39 of these patients (15%), and in 25 (10%) indurations were ≥ 10 mm. In addition, 40 (16%) had positive QFT-GIT outcomes, and 34 (14%) indeterminate outcomes. If the 34 patients with indeterminate QFT-GIT results were excluded from the overall agreement analysis, the agreement between the TST results (induration size ≥ 5 mm) and the QFT-GIT results in the 210 patients with clear QFT results was poor (κ = 0.08, 95% confidence interval [CI] -0.06 to 0.24), as it was for the patients with indurations ≥ 10 mm (κ = 0.15, 95% CI -0.004 to 0.31). During follow up, 2 patients developed TB after HCT. The incidence of TB in the patients with positive QFT-GIT outcomes was 2.80 per 100 person-years (95% CI 0.07-15.81), whereas among those with positive TST (≥ 5 mm) results, it was 0 per 100 person-years (95% CI 0-8.00). However, this finding should be cautiously interpreted because of the relatively short follow up and the fact that the sample size of the study cohort did not have adequate power. In conclusion, our data show that, although the frequencies of positive outcomes in the 2 TB screening tests were similar, the overall agreement between the TST and the QFT-GIT test was poor, regardless of BCG vaccination history.
Lee, Min Young; Kim, Young Jin; Lee, Hee Joo; Park, Tae Sung
Introduction. Mean platelet volume (MPV) has been thought as a useful index of platelet activation. It is supposed that MPV is also associated with several inflammatory and infectious diseases. Korea still has a high incidence of tuberculosis (TB). The aim of this study was to investigate MPV as an inflammatory marker in TB patients. Materials and Methods. MPV were determined in 221 patients with TB and 143 individuals for control group. MPV was estimated by an Advia 2120 (Siemens Healthcare Diagnostics, Tarrytown, NY, USA). Results. In the TB patient group, a positive correlation was found between CRP and MPV. Age and MPV had a positive correlation in TB patient group. Conclusions. We conclude that there is a significant relation between MPV and inflammatory conditions. MPV can be an inflammatory marker to determine the disease activity in TB patients. PMID:27419136
OBJECTIVES The risk of transmission of Mycobacterium tuberculosis from patients to health care workers (HCWs) is a neglected problem in many countries, including Iran. The aim of this study was to estimate the prevalence of latent tuberculosis (TB) infection (LTBI) among TB laboratory staff in Iran, and to elucidate the risk factors associated with LTBI. METHODS All TB laboratory staff (689 individuals) employed in the TB laboratories of 50 Iranian universities of medical sciences and a random sample consisting of 317 low-risk HCWs were included in this cross-sectional study. Participants with tuberculin skin test indurations of 10 mm or more were considered to have an LTBI. RESULTS The prevalence of LTBI among TB laboratory staff and low-risk HCWs was 24.83% (95% confidence interval [CI], 21.31 to 27.74%) and 14.82% (95% CI, 11.31 to 19.20%), respectively. No active TB cases were found in either group. After adjusting for potential confounders, TB laboratory staff were more likely to have an LTBI than low-risk HCWs (prevalence odds ratio, 2.06; 95% CI, 1.35 to 3.17). CONCLUSIONS This study showed that LTBI are an occupational health problem among TB laboratory staff in Iran. This study reinforces the need to design and implement simple, effective, and affordable TB infection control programs in TB laboratories in Iran. PMID:28092930
Mativandlela, Sannah Patience Nkami; Meyer, Jacob Jacobus Marion; Hussein, Ahmed A; Houghton, Peter J; Hamilton, Chris J; Lall, Namrita
Seven ethnobotanically selected medicinal plants were screened for their antimycobacterial activity. The minimum inhibitory concentration (MIC) of four plants namely Artemisia afra, Dodonea angustifolia, Drosera capensis and Galenia africana ranged from 0.781 to 6.25 mg/mL against Mycobacterium smegmatis. G. africana showed the best activity exhibiting an MIC of 0.78 mg/mL and a minimum bactericidal concentration (MBC) of 1.56 mg/mL. The MICs of ethanol extracts of D. angustifolia and G. africana against M. tuberculosis were found to be 5.0 and 1.2 mg/mL respectively. The mammalian cytotoxicity IC(50) value of the most active antimycobacterial extract, from G. africana, was found to be 101.3 microg/mL against monkey kidney Vero cells. Since the ethanol G. africana displayed the best antimycobacterial activity, it was subjected to fractionation which led to the isolation of a flavone, 5,7,2'-trihydroxyflavone. The MIC of this compound was found to be 0.031 mg/mL against M. smegmatis and 0.10 mg/mL against M. tuberculosis. This study gives some scientific basis to the traditional use of these plants for TB-related symptoms.
[Guidelines for the diagnosis and treatment of latent tuberculosis infection and active tuberculosis in patients with inflammatory joint diseases proposed for treatment with tumour necrosis factor alpha antagonist drugs].
Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena
The Portuguese Society of Rheumatology (SPR) and the Portuguese Society of Pulmonology (SPP) have developed guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (AT) in patients with inflammatory joint diseases (IJD), namely rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, treated with tumour necrosis factor alpha (TNF-a) antagonists. Due to the high risk of tuberculosis (TB) in patients with IJD, LTBI and AT screening should be performed as soon as possible, ideally at the moment of IJD diagnosis. Even if TB screening was performed at the beginning of the disease, the evaluation should be repeated before starting anti-TNF-a therapy. When TB (LTBI or AT) treatment is indicated, it should be performed before the beginning of anti-TNF-a therapy. If the IJD activity requires urgent anti-TNF-a therapy, these drugs can be started after two months of antituberculosis therapy in AT cases, or after one month in LTBI cases. Chest X-ray is mandatory for all patients. If abnormal, e.g. Gohn complex, the patient should be treated as LTBI; residual lesions require the exclusion of AT and patients with history of untreated or incomplete TB treatment should be treated as LTBI. In cases of suspected active lesions, AT diagnosis should be confirmed and adequate therapy initiated. Tuberculin skin test (TST), with two units of RT23, should be performed in all patients. If induration is less than 5 mm, the test should be repeated after 1 to 2 weeks, on the opposite forearm, and should be considered negative if the result is again inferior to 5 mm. Positive TST implicates LTBI treatment. If TST is performed in immunosuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNF-a therapy, even in the presence of a negative test.
George, Parakkal Jovvian; Pavan Kumar, Nathella; Jaganathan, Jeeva; Dolla, Chandrakumar; Kumaran, Paul; Nair, Dina; Banurekha, Vaithilingam V; Shen, Kui; Nutman, Thomas B; Babu, Subash
Helminth infections are known to induce modulation of both innate and adaptive immune responses in active and latent tuberculosis (TB). However, the role of helminth infections in modulating systemic cytokine responses in active and latent tuberculosis (LTB) is not known. To define the systemic cytokine levels in helminth-TB coinfection, we measured the circulating plasma levels of Type 1, Type 2, Type 17, other pro-inflammatory and regulatory cytokines in individuals with active TB (ATB) with or without coexistent Strongyloides stercoralis (Ss) infection by multiplex ELISA. Similarly, we also measured the same cytokine levels in individuals with LTB with or without concomitant Ss infection in a cross-sectional study. Our data reveal that individuals with ATB or LTB and coexistent Ss infection have significantly lower levels of Type 1 (IFNγ, TNFα and IL-2) and Type 17 (IL-17A and IL-17F) cytokines compared to those without Ss infection. In contrast, those with ATB and LTB with Ss infection have significantly higher levels of the regulatory cytokines (IL-10 and TGFβ), and those with LTB and Ss infection also have significantly higher levels of Type 2 cytokines (IL-4, IL-5 and IL-13) as well. Finally, those with LTB (but not ATB) exhibit significantly lower levels of other pro-inflammatory cytokines (IFNα, IFNβ, IL-6, IL-12 and GM-CSF). Our data therefore reveal a profound effect of Ss infection on the systemic cytokine responses in ATB and LTB and indicate that coincident helminth infections might influence pathogenesis of TB infection and disease.
Sardella, Isabela Gama; Singh, Mahavir; Kumpfer, Susanne; Heringer, Rafael Ribeiro; Saad, Maria Helena Féres; Sohler, Marzia Puccioni
To evaluate commercial Lionex TB together with four antigens of Mycobacterium tuberculosis (MPT-64, MT10.3, 16 kDa and 38 kDa) for IgG and IgA cerebrospinal fluid (CSF) detection in the diagnosis of tuberculosis meningitis (TBM) with CSF negative acid-fast bacilli staining, 19 cases of TBM, 64 cases of other infectious meningoencephalitis and 73 cases of other neurological disorders were tested by enzyme linked immunosorbent assay. IgA-MPT-64 and IgG Lionex showed the highest sensitivities, specificities, positive predictive value and negative predictive value (63.2%, 47.4%; 95%, 93.7%; 40%, 98% and 28.4%, 97.1%, respectively). However, while grey zone was 12.7% and 6%, respectively, lowering sensitivity but maintains high specificity (>or= 95%). High protein concentration in CSF was associated with antibody positivity CSF/HIV+ which did not influence the sensitivity of both tests. To our knowledge, this is the first description of IgA-MPT-64 and IgG Lionex antibodies in CSF-TBM and, although there is good specificity, adjustments are needed based on antigen composition to enhance sensitivity.
Sali, Michela; De Maio, Flavio; Caccuri, Francesca; Campilongo, Federica; Sanguinetti, Maurizio; Fiorentini, Simona; Delogu, Giovanni; Giagulli, Cinzia
The rapid diagnosis of tuberculosis (TB) and the detection of drug-resistant Mycobacterium tuberculosis strains are critical for successful public health interventions. Therefore, TB diagnosis requires the availability of diagnostic tools that allow the rapid detection of M. tuberculosis and drug resistance in clinical samples. Here, we performed a multicenter study to evaluate the performance of the Seegene Anyplex MTB/NTM MDR-TB assay, a new molecular method based on a multiplex real-time PCR system, for detection of Mycobacterium tuberculosis complex (MTBC), nontuberculous mycobacteria (NTM), and genetic determinants of drug resistance. In total, the results for 755 samples (534 pulmonary and 221 extrapulmonary samples) were compared with the results of smears and cultures. For pulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 86.4% and 75.0%, respectively, and the specificities were 99% and 99.4%. For extrapulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 83.3% and 50.0%, respectively, and the specificities of both were 100%. The negative and positive predictive values of the Anyplex assay for pulmonary specimens were 97% and 100%, respectively, and those for extrapulmonary specimens were 84.6% and 100%. The sensitivities of the Anyplex assay for detecting isoniazid resistance in MTBC strains from pulmonary and extrapulmonary specimens were 83.3% and 50%, respectively, while the specificities were 100% for both specimen types. These results demonstrate that the Anyplex MTB/NTM MDR-TB assay is an efficient and rapid method for the diagnosis of pulmonary and extrapulmonary TB and the detection of isoniazid resistance.
De Maio, Flavio; Caccuri, Francesca; Campilongo, Federica; Sanguinetti, Maurizio; Fiorentini, Simona; Giagulli, Cinzia
The rapid diagnosis of tuberculosis (TB) and the detection of drug-resistant Mycobacterium tuberculosis strains are critical for successful public health interventions. Therefore, TB diagnosis requires the availability of diagnostic tools that allow the rapid detection of M. tuberculosis and drug resistance in clinical samples. Here, we performed a multicenter study to evaluate the performance of the Seegene Anyplex MTB/NTM MDR-TB assay, a new molecular method based on a multiplex real-time PCR system, for detection of Mycobacterium tuberculosis complex (MTBC), nontuberculous mycobacteria (NTM), and genetic determinants of drug resistance. In total, the results for 755 samples (534 pulmonary and 221 extrapulmonary samples) were compared with the results of smears and cultures. For pulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 86.4% and 75.0%, respectively, and the specificities were 99% and 99.4%. For extrapulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 83.3% and 50.0%, respectively, and the specificities of both were 100%. The negative and positive predictive values of the Anyplex assay for pulmonary specimens were 97% and 100%, respectively, and those for extrapulmonary specimens were 84.6% and 100%. The sensitivities of the Anyplex assay for detecting isoniazid resistance in MTBC strains from pulmonary and extrapulmonary specimens were 83.3% and 50%, respectively, while the specificities were 100% for both specimen types. These results demonstrate that the Anyplex MTB/NTM MDR-TB assay is an efficient and rapid method for the diagnosis of pulmonary and extrapulmonary TB and the detection of isoniazid resistance. PMID:26491178
Introduction Afghanistan has faced health consequences of war including those due to displacement of populations, breakdown of health and social services, and increased risks of disease transmission for over three decades. Yet it was able to restructure its National Tuberculosis Control Programme (NTP), integrate tuberculosis treatment into primary health care and achieve most of its targets by the year 2011. What were the processes that enabled the programme to achieve its targets? More importantly, what were the underpinning factors that made this success possible? We addressed these important questions through a case study. Case description We adopted a processes and outcomes framework for this study, which began with examining the change in key programme indicators, followed by backwards tracing of the processes and underlying factors, responsible for this change. Methods included review of the published and grey literature along with in-depth interviews of 15 key informants involved with the care of tuberculosis patients in Afghanistan. Discussion and evaluation TB incidence and mortality per 100,000 decreased from 325 and 92 to 189 and 39 respectively, while case notification and treatment success improved during the decade under study. Efficient programme structures were enabled through high political commitment from the Government, strong leadership from the programme, effective partnership and coordination among stakeholders, and adequate technical and financial support from the development partners. Conclusions The NTP Afghanistan is an example that public health programmes can be effectively implemented in fragile states. High political commitment and strong local leadership are essential factors for such programmes. To ensure long-term effectiveness of the NTP, the international support should be withdrawn in a phased manner, coupled with a sequential increase in resources allocated to the NTP by the Government of Afghanistan. PMID:24507446
Qian, Xu; Nguyen, Duc T.M.; Li, Yaojun; Lyu, Jianxin; Graviss, Edward A.; Hu, Tony Y.
Background There is an urgent need for methods that can rapidly and accurately assess therapeutic responses in patients with active tuberculosis (TB) in order to predict treatment outcomes. Exposure to bacterial pathogens can rapidly activate the plasma contact system, triggering the release of bradykinin (BK) and its metabolite desArg9-bradykinin (DABK) to induce inflammation and innate immune responses. We hypothesized that serum BK and DABK levels might act as sensitive immune response signatures for changes in Mycobacterium tuberculosis (Mtb) burden, and therefore examined how serum levels of these markers corresponded with anti-TB therapy in a small cohort of active TB cases. Methods Nanotrap Mass-Spectrometry (MS) was used to analyze serial blood specimens from 13 HIV-negative adults with microbiologically confirmed active TB who were treated with first-line anti-TB chemotherapy. MS signal for BK (m/z 1060.5) and DABK (m/z 904.5) serum peptides were evaluated at multiple time-points (before, during, and after treatment) to evaluate how BK and DABK levels corresponded with disease status. Results Serum BK levels declined from pretreatment baseline levels during the early stage anti-TB therapy (induction phase) and tended to remain below baseline levels during extended treatment (consolidation phase) and after therapy completion. BK levels were consistent with induction phase sputum culture conversions indicative of decreased Mtb burden reflecting good treatment responses. Serum DABK levels tended to increase during the induction phase and decrease at consolidation and post-therapy time points, which may indicate a shift from active disease to chronic inflammation to a disease free state. Elevated BK and DABK levels after treatment completion in one patient may be related to the subsequent recurrent TB disease. Conclusions Our pilot data suggests that changes in the circulating BK and DABK levels in adult TB patients can be used as potential surrogate markers
Dheda, Keertan; Barry, Clifton E; Maartens, Gary
Although the worldwide incidence of tuberculosis has been slowly decreasing, the global disease burden remains substantial (∼9 million cases and ∼1·5 million deaths in 2013), and tuberculosis incidence and drug resistance are rising in some parts of the world such as Africa. The modest gains achieved thus far are threatened by high prevalence of HIV, persisting global poverty, and emergence of highly drug-resistant forms of tuberculosis. Tuberculosis is also a major problem in health-care workers in both low-burden and high-burden settings. Although the ideal preventive agent, an effective vaccine, is still some time away, several new diagnostic technologies have emerged, and two new tuberculosis drugs have been licensed after almost 50 years of no tuberculosis drugs being registered. Efforts towards an effective vaccine have been thwarted by poor understanding of what constitutes protective immunity. Although new interventions and investment in control programmes will enable control, eradication will only be possible through substantial reductions in poverty and overcrowding, political will and stability, and containing co-drivers of tuberculosis, such as HIV, smoking, and diabetes.
This brief is the first of a series of documents based on the Tuberculosis Annual Report 2014. It includes a summary of tuberculosis (TB) statistics, including data on foreign-born TB patients notified and registered in Japan in 2014. For the first time, the number of newly notified cases (all forms of TB) fell below 20,000. In 2014, a total of 19,615 patients were notified, a rate of 15.4 per 100,000 population The number of sputum-smear positive pulmonary. TB patients notified was 7,651, a rate of 6.0 per 100,000 population. The number of patients with latent TB infections increased slightly from 7,147 in 2013 to 7,562 in 2014. The proportion of miliary TB cases has constantly increased over the past 10 years, especially among women aged 80 years and older. The number of foreign-born TB patients continued to increase from 1,064 in 2013 to 1,101 in 2014. In 2014, new foreign-born TB patients aged 20-29 years accounted for 44.1% of all new TB patients in that age group. Among foreign-born TB patients, half were from the Philippines (26.5%) and China (23.5%). However, the number of patients from Vietnam and Nepal is increasing. Among foreign-born TB patients, 28% were regular employees, 26% were students, and 20% were unemployed. The changing trend in the nationality of foreign students entering Japan may at least partially explain the differences in TB burden among foreign-born patients, by country of birth. As we expect to see the proportion of foreign-born TB patients continue to rise, more tailored case identification and treatment support activities are needed.
... Sites Podcasts QR Codes RSS Feeds Social Bookmarking Social Network Sites Text Messaging Twitter Video Games Video Sharing ... possible, and that people whose initial test is negative and who are at high risk for TB ...
Bae, Won; Park, Kyoung Un; Song, Eun Young; Kim, Se Joong; Lee, Yeon Joo; Park, Jong Sun; Cho, Young-Jae; Yoon, Ho Il; Yim, Jae-Joon; Lee, Choon-Taek; Lee, Jae Ho
Currently, there are two types of interferon-gamma release assays (IGRAs) in use for the detection of tuberculosis (TB) infection, the QuantiFERON-TB Gold In-Tube test (GFT-GIT) and T-SPOT.TB. Owing to contradictory reports regarding whether the results of these IGRAs are affected by the age of the patient, we aimed to determine if these two tests have age-related differences in sensitivity. We retrospectively reviewed the medical records of diagnosed TB patients who were tested using either QFT-GIT or T-SPOT.TB from February 2008 to December 2013. The positivity of the two tests was analyzed and compared with true TB infection, which was defined as active TB based on either a positive Mycobacterium culture or a positive TB polymerase chain reaction. The QFT-GIT group included 192 TB patients, and the T-SPOT.TB group included 212 TB patients. Of the patients with pulmonary TB, 76 (39.6%) were in the QFT-GIT group and 143 (67.5%) in the T-SPOT.TB group. The overall sensitivity was 80.2% for QFT-GIT and 91.0% for T.SPOT.TB. The sensitivities of QFT-GIT and T-SPOT.TB according to age group were as follows: <29 years, 93.3% and 96.7%; 30–49 years, 86.5% and 94.7%; 50–69 years, 76.8% and 87.5%; and >70 years, 68.3% and 85.7%, respectively. The trend of age-related changes in sensitivity was significant for both QFT-GIT (p = 0.004) and T.SPOT.TB (p = 0.039). However, only QFT-GIT was significantly related to age in the multivariate analysis. QFT-GIT, but not T-SPOT.TB, was significantly affected by patient age. PMID:27258377
Kumar, Anuradha; Colmenarejo, Gonzalo; Pérez, Esther; Gonzalez, Ruben R.; Torres, Pedro; Calvo, David; Gómez, Ruben M.; Ortega, Fátima; Jiménez, Elena; Gabarro, Raquel C.; Rullás, Joaquín; Ballell, Lluis
Antifolates are widely used to treat several diseases but are not currently used in the first-line treatment of tuberculosis, despite evidence that some of these molecules can target Mycobacterium tuberculosis (Mtb) bacilli in vitro. To identify new antifolate candidates for animal-model efficacy studies of tuberculosis, we paired knowledge and tools developed in academia with the infrastructure and chemistry resources of a large pharmaceutical company. Together we curated a focused library of 2508 potential antifolates, which were then tested for activity against live Mtb. We identified 210 primary hits, confirmed the on-target activity of potent compounds, and now report the identification and characterization of 5 hit compounds, representative of 5 different chemical scaffolds. These antifolates have potent activity against Mtb and represent good starting points for improvement that could lead to in vivo efficacy studies. PMID:26771003
The intricate relationship between tuberculosis (TB) and immune system remains poorly understood. It is generally believed that weakening of the immune response against Mycobacterium tuberculosis leads to reactivation of latent infection into the active pulmonary disease. However, heterogeneous nature of TB and failure of rationally designed vaccines in clinical trials raises serious questions against the simplistic view of TB as an outcome of weakened immunity. In the wake of accumulating human TB data, it is argued here that a hyperactive antimycobacterial immune response is to blame for the pathogenesis of pulmonary TB in immunocompetent adults. Direct and indirect evidence supporting this notion is presented in this article. Revisiting the role of immune system in TB pathogenesis will pave the way for effective anti-TB vaccines.
... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...
... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...
... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...
Tuberculosis is a devastating disease that affects humans and many animal species. In humans, tuberculosis (TB) is mainly caused by Mycobacterium tuberculosis, while most cases in cattle are caused by Mycobacterium bovis. However, Mb can also cause, albeit rarely, human TB. In this issue, Wu et al. ...
Background Plants have long been investigated as a source of antibiotics and other bioactives for the treatment of human disease. New Zealand contains a diverse and unique flora, however, few of its endemic plants have been used to treat tuberculosis. One plant, Laurelia novae-zelandiae, was reportedly used by indigenous Maori for the treatment of tubercular lesions. Methods Laurelia novae-zelandiae and 44 other native plants were tested for direct anti-bacterial activity. Plants were extracted with different solvents and extracts screened for inhibition of the surrogate species, Mycobacterium smegmatis. Active plant samples were then tested for bacteriostatic activity towards M. tuberculosis and other clinically-important species. Results Extracts of six native plants were active against M. smegmatis. Many of these were also inhibitory towards M. tuberculosis including Laurelia novae-zelandiae (Pukatea). M. excelsa (Pohutukawa) was the only plant extract tested that was active against Staphylococcus aureus. Conclusions Our data provide support for the traditional use of Pukatea in treating tuberculosis. In addition, our analyses indicate that other native plant species possess antibiotic activity. PMID:20537175
Paul, Nibedita; Deka, Amrita; Mohanta, Dambarudhar
The present work reports on the effect of Tb³⁺ doping on the luminescence and photocatalytic performance of nano-structured titania derived through a sol-gel route. X-ray diffraction patterns have revealed the existence of anatase phase with and without Tb³⁺ doping and with an improved orientation factor along (004) and (200) planes. Transmission electron microscopy and selective area electron diffraction studies, while exhibiting ample poly-crystallinity feature, have predicted an average particle size of ~9 nm and ~6 nm for the un-doped and 5% Tb³⁺ doped nano-titania samples; respectively. Apart from emissions accompanied by different types of defects, Tb³⁺ related transitions, such as, ⁵D₃ → ⁷F₅, ⁵D₃ → ⁷F₄, and ⁵D₄ → ⁷F₆ were identified in the photoluminescence spectra. Brunauer-Emmett-Teller surface area analysis, as carried out on a Tb³⁺ doped nano-titania system, has demonstrated a more-open hysteretic loop owing to significant difference of N₂ adsorption/desorption rates. The photocatalytic activity of nano-titania, as evaluated from the nature of degradation of methyl orange under UV illumination, exhibited the highest efficiency for a Tb³⁺ doping level of 2.5%. The augmented photocatalytic degradation has also been discussed in the light of a model based on pseudo first-order kinetics.
... Tuberculosis AGENCY: Occupational Safety and Health Administration (OSHA), Department of Labor. ACTION: Notice..., 1997, OSHA published its proposed standard to regulate occupational exposure to tuberculosis (TB) (62... preliminary risk assessment for occupational exposure to tuberculosis. DATES: Comments and data...
Grobler, Liesl; Nagpal, Sukrti; Sudarsanam, Thambu D; Sinclair, David
Background Tuberculosis and malnutrition are linked in a complex relationship. Tuberculosis may cause undernutrition through increased metabolic demands and decreased intake, and nutritional deficiencies may worsen the disease, or delay recovery by depressing important immune functions. At present, there is no evidence-based nutritional guidance for adults and children being treated for tuberculosis. Objectives To assess the effects of oral nutritional supplements in people being treated with antituberculous drug therapy for active tuberculosis. Search methods We searched the Cochrane Infectious Disease Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL; Issue 1, 2016), MEDLINE (from 1946 to 4 February 2016), EMBASE (from 1980 to 4 February 2016), LILACS (from 1982 to 4 February 2016), the metaRegister of Controlled Trials (mRCT), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and the Indian Journal of Tuberculosis up to 4 February 2016, and checked the reference lists of all included studies. Selection criteria Randomized controlled trials that compared any oral nutritional supplement given for at least four weeks with no nutritional intervention, placebo, or dietary advice only for people being treated for active tuberculosis. The primary outcomes of interest were all-cause death, and cure at six and 12 months. Data collection and analysis Two review authors independently selected trials for inclusion, and extracted data and assessed the risk of bias in the included trials. We presented the results as risk ratios (RR) for dichotomous variables, and mean differences (MD) for continuous variables, with 95% confidence intervals (CIs). Where appropriate, we pooled data from trials with similar interventions and outcomes. We assessed the quality of the evidence using the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Main results Thirty-five trials
Bates, Matthew; Marais, Ben J; Zumla, Alimuddin
The 18th WHO Global Tuberculosis Annual Report indicates that there were an estimated 8.6 million incident cases of tuberculosis (TB) in 2012, which included 2.9 million women and 530,000 children. TB caused 1.3 million deaths including 320,000 human immunodeficiency virus (HIV)-infected people; three-quarters of deaths occurred in Africa and Southeast Asia. With one-third of the world's population latently infected with Mycobacterium tuberculosis (Mtb), active TB disease is primarily associated with a break down in immune surveillance. This explains the strong link between active TB disease and other communicable diseases (CDs) or noncommunicable diseases (NCDs) that exert a toll on the immune system. Comorbid NCD risk factors include diabetes, smoking, malnutrition, and chronic lung disease, all of which have increased relentlessly over the past decade in developing countries. The huge overlap between killer infections such as TB, HIV, malaria, and severe viral infections with NCDs, results in a "double burden of disease" in developing countries. The current focus on vertical disease programs fails to recognize comorbidities or to encourage joint management approaches. This review highlights major disease overlaps and discusses the rationale for better integration of tuberculosis care with services for NCDs and other infectious diseases to enhance the overall efficiency of the public health responses.
Uplekar, Mukund; Raviglione, Mario
The 67th World Health Assembly of 2014 adopted the "End TB Strategy" with a vision of making the world free of tuberculosis (TB) and with the goal of ending the global TB epidemic by the year 2035. World Health Organization's "End TB Strategy" captures this holistic response in its four principles and three pillars. The three high-level indicators of the "End TB Strategy" - reductions in TB deaths, reductions in the TB incidence rate and the percentage of TB patients and their households experiencing catastrophic costs - are relevant to all countries.
Motamedifar, Mohammad; Abadi, Ali Reza Hassan; Moghadam, Mahboube Nakhzari
Background Tuberculosis (TB) is the leading cause of mortality among human immunodeficiency virus (HIV) patients and the majority of them occur in developing countries. The aims of the present study were to determine the frequency of HIV/TB co-infection and other probable associated factors. Methods This 10 year retrospective study was conducted on 824 HIV patients in the south-west of Iran. HIV infection was diagnosed by the enzyme linked immunosorbent assay and confirmed by Western blot. TB diagnosis was based on consistency of the clinical manifestations, chest X-ray, and microscopic examination. Drug susceptibility testing was done by the proportional method on Löwenstein-Jensen media. Results Of 824 HIV patients, 59 (7.2%) were identified as TB co-infected and the majority (86.4%) of them were male. Of the overall TB infected patients, 6 cases (10.2%) showed multidrug-resistant with the mean CD4+ lymphocyte count of 163±166 cells/mm3. The main clinical forms of TB were pulmonary (73%). There was a significant (p<0.05) correlation between TB infection and CD4+ lymphocyte counts ≤200 cells/mm3, gender, prison history, addiction history, and highly active anti-retroviral therapy. Conclusion We reported novel information on frequency of HIV/TB co-infection and multidrug resistant-TB outcome among co-infected patients that could facilitate better management of such infections on a global scale. PMID:26175780
Raju, Bindu; Hoshino, Yoshihiko; Belitskaya-Lévy, Ilana; Dawson, Rod; Ress, Stanley; Gold, Jeffrey A.; Condos, Rany; Pine, Richard; Brown, Stuart; Nolan, Anna; Rom, William N.; Weiden, Michael D.
The host response to Mycobacterium tuberculosis includes macrophage activation, inflammation with increased immune effector cells, tissue necrosis and cavity formation, and fibrosis, distortion, and bronchiectasis. To evaluate the molecular basis of the immune response in the lungs of patients with active pulmonary tuberculosis (TB), we used bronchoalveolar lavage to obtain cells at the site of infection. Affymetrix Genechip micro-arrays and cDNA nylon filter microarrays interrogated gene expression in BAL cells from 11 healthy controls and 17 patients with active pulmonary TB. We found altered gene expression for 69 genes in TB versus normal controls that included cell surface markers, cytokines, chemokines, receptors, transcription factors, and complement components. In addition, TB BAL cell gene expression patternssegregated into 2 groups: one suggestive of a T helper type 1 (Th1) cellular immune response with increased STAT-4, IFN-γ receptor, and MIG expression with increased IFN-γ protein levels in BAL fluid; the other group displayed characteristics of Th2 immunity with increased STAT-6, CD81, and IL-10 receptor expression. We were able to demonstrate that a Th2 presentation could change to a Th1 pattern after anti-tuberculous treatment in one TB patient studied serially. These gene expression data support the conclusion that pulmonary TB produces a global change in the BAL cell transcriptome with manifestations of either Th1 or Th2 immunity. PMID:17921069
DiNardo, Andrew R; Guy, Elizabeth
The incidence and death rates from tuberculosis (TB) have declined through concerted efforts in the diagnosis and treatment of active disease. Despite this, 9.6 million new cases and 1.1 million deaths in 2014 are unacceptably high. To decrease the rates of TB further, the huge number of persons with latent TB infection (LTBI) from whom new cases will arise has to be addressed with a sense of priority. Identifying the highest risk groups and providing effective treatment has been shown to decrease active TB. Further research to refine the predictors of reactivation and shorter effective treatments are urgently needed. Implementing intensified case finding, testing and treatment for LTBI will require continued investment in health care capacity at multiple levels.
Malhotra, Shelly; Koeut, Pichenda; Thai, Sopheak; Khun, Kim Eam; Colebunders, Robert; Lynen, Lut
Background While community-based active case finding (ACF) for tuberculosis (TB) holds promise for increasing early case detection among hard-to-reach populations, limited data exist on the acceptability of active screening. We aimed to identify barriers and explore facilitators on the pathway from diagnosis to care among TB patients and health providers. Methods Mixed-methods study. We administered a survey questionnaire to, and performed in-depth interviews with, TB patients identified through ACF from poor urban settlements in Phnom Penh, Cambodia. Additionally, we conducted focus group discussions and in-depth interviews with community and public health providers involved in ACF, respectively. Results Acceptance of home TB screening was strong among key stakeholders due to perceived reductions in access barriers and in direct and indirect patient costs. Privacy and stigma were not an issue. To build trust and facilitate communication, the participation of community representatives alongside health workers was preferred. Most health providers saw ACF as complementary to existing TB services; however, additional workload as a result of ACF was perceived as straining operating capacity at public sector sites. Proximity to a health facility and disease severity were the strongest determinants of prompt care-seeking. The main reasons reported for delays in treatment-seeking were non-acceptance of diagnosis, high indirect costs related to lost income/productivity and transportation expenses, and anticipated side-effects from TB drugs. Conclusions TB patients and health providers considered home-based ACF complementary to facility-based TB screening. Strong engagement with community representatives was believed critical in gaining access to high risk communities. The main barriers to prompt treatment uptake in ACF were refusal of diagnosis, high indirect costs, and anticipated treatment side-effects. A patient-centred approach and community involvement were essential
Babayigit, Cenk; Ozer, Burcin; Inandi, Tacettin; Ozer, Cahit; Duran, Nizami; Gocmen, Orhan
Background Tuberculin skin test (TST) has been used for years as an aid in diagnosing latent tuberculosis infection (LTBI) but it suffers from a number of well-documented performance and logistic problems. Quantiferon-TB Gold In Tube test (QFT-GIT) has been reported to have better sensitivity and specifity than TST. In this study, it was aimed to compare the performance of a commercial IFN-γ release assay (QFT-GIT) with TST in the diagnosis of HCWs at risk for latent TB infection in BCG vaccinated population. Material/Methods Hundred healthy volunteer health care workers were enrolled. All were subjected to TST and QFT-GIT. Results were compared among Health Care Workers (HCWs) groups in terms of profession, workplace, working duration. Results TST is affected by previous BCG vaccinations and number of cases with QFT-GIT positivity is increased in accordance with the TST induration diameter range. QFT-GIT result was negative in 17 of 32 TST positive (≥15 mm) cases and positive in 4 of 61 cases whose TST diameters are between 6–14 mm, that is attritutable to previous BCG vaccination(s). It was negative in all cases with TST diameters between 0–5 mm. HCWs with positive QFT-GIT results were significantly older than the ones with negative results. Furthermore duration of work was significantly longer in QFT-GIT positive than in negative HCWs. Conclusions There was a moderate concordance between QFT-GIT and TST, when TST result was defined as positive with a ≥15 mm diameter of induration. We suggest that QFT-GIT can be used as an alternative to TST for detection of LTBI, especially in groups with high risk of LTBI and in population with routine BCG vaccination program. PMID:24681806
Taylor, Jessica M.; Davidson, Rebecca M.; Strong, Michael
Tuberculosis (TB) continues to be a serious global health problem, resulting in >1.4 million deaths each year. Of increasing concern is the evolution of antibiotic resistant strains of the bacterium that causes TB. Using this real-world scenario, we created a 90-minute activity for high school or undergraduate students to use online…
Gregg, Edward W.; Jonnalagadda, Sasi; Phares, Christina R.; Zhou, Weigong; Painter, John A.
Diabetes is associated with an increased risk for active tuberculosis (TB) disease. We conducted a case–control study and found a significant association between diabetes and TB disease among US-bound refugees. These findings underscore the value of collaborative management of both diseases. PMID:28221111
Baquero-Artigao, F; Mellado Peña, M J; Del Rosal Rabes, T; Noguera Julián, A; Goncé Mellgren, A; de la Calle Fernández-Miranda, M; Navarro Gómez, M L
Tuberculosis (TB) screening in pregnancy using tuberculin skin test (TST) is recommended in case of symptoms of TB disease, close contact with a patient with infectious TB, or high risk of developing active disease. The new interferon gamma release assay (IGRA) tests are recommended in BCG-vaccinated pregnant women with positive TST and no known risk factors for TB, and in those immunocompromised, with clinical suspicion of TB but negative TST. TB diagnosis is difficult due to the non-specific symptoms, the increased frequency of extrapulmonary disease, the delay in radiological examinations, and the high rate of tuberculin anergy. Neonatal TB can be acquired in utero (congenital TB), or through airborne transmission after delivery (postnatal TB). Congenital TB is extremely rare and does not cause fetal malformations. It may be evident at birth, although it usually presents after the second week of life. In newborns with no family history of TB, the disease should be considered in cases of miliary pneumonia, hepatosplenomegaly with focal lesions, or lymphocytic meningitis with hypoglycorrhachia, especially in those born to immigrants from high TB-burden countries. TST is usually negative, and IGRAs have lower sensitivity than in older children. However, the yield of acid-fast smear and culture is higher, mostly in congenital TB. Molecular diagnosis techniques enable early diagnosis and detection of drug resistance mutations. There is a substantial risk of disseminated disease and death.
Torres-Juarez, Flor; Cardenas-Vargas, Albertina; Montoya-Rosales, Alejandra; González-Curiel, Irma; Garcia-Hernandez, Mariana H.; Enciso-Moreno, Jose A.; Hancock, Robert E. W.
Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to a great extent on the innate immune response against mycobacteria. Host defense peptides (HDP) are one of the first barriers to counteract infection. Cathelicidin (LL-37) is an HDP that has many immunomodulatory effects besides its weak antimicrobial activity. Despite advances in the study of the innate immune response in tuberculosis, the immunological role of LL-37 during M. tuberculosis infection has not been clarified. Monocyte-derived macrophages were infected with M. tuberculosis strain H37Rv and then treated with 1, 5, or 15 μg/ml of exogenous LL-37 for 4, 8, and 24 h. Exogenous LL-37 decreased tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) while inducing anti-inflammatory IL-10 and transforming growth factor β (TGF-β) production. Interestingly, the decreased production of anti-inflammatory cytokines did not reduce antimycobacterial activity. These results are consistent with the concept that LL-37 can modulate the expression of cytokines during mycobacterial infection and this activity was independent of the P2X7 receptor. Thus, LL-37 modulates the response of macrophages during infection, controlling the expression of proinflammatory and anti-inflammatory cytokines. PMID:26351280
The problems of diagnosis, treatment and management of tuberculosis associated with HIV infection in Africa are placed in perspective by the former director of the Kenya Medical Research Institute. Tuberculosis (TB) has increased as much as 3-fold in many African countries due to heightened susceptibility of HIV patients. HIV infection may both re-activate latent TB, which virtually all Africans harbor, or increase the likelihood of exogenous infection or re-infection by TB. In most of Africa diagnosis by stained sputum smear is standard: in late AIDS, this method may yield false negatives due to non-pulmonary TB, or pulmonary TB with a negative smear. Chest x-rays are also atypical, since cavitation of the upper zones is not as common, but lobar consolidation and lower zone involvement, and various unusual findings are likely. There is no evidence that mycobacterium avium intracellular has occurred in Africa. Treatment in Africa often centers on long-term thiazina (thiacetazone and isoniazid combined). HIV+ patients are more prone to skin rashes or even lethal epidermal neurolysis as a complication of treatment. Treated patients should be monitored for other symptoms such as diarrhea, recurrent fevers, other chest infections, cerebral space occupying lesions, urinary infections. Many can be treated with broad spectrum antibiotics such as chloramphenicol. Nursing HIV-infected young adults is an expensive and burdensome prospect for overworked and underpaid staff, but curing TB in AIDS patients is possible and worthwhile because of the public health advantages.
Gupte, Akshay; Padmapriyadarsini, Chandrasekaran; Mave, Vidya; Kadam, Dileep; Suryavanshi, Nishi; Shivakumar, Shri Vijay Bala Yogendra; Kohli, Rewa; Gupte, Nikhil; Thiruvengadam, Kannan; Kagal, Anju; Meshram, Sushant; Bharadwaj, Renu; Khadse, Sandhya; Ramachandran, Geetha; Hanna, Luke Elizabeth; Pradhan, Neeta; Gomathy, N S; DeLuca, Andrea; Gupta, Amita; Swaminathan, Soumya
Introduction Tuberculosis disease (TB) remains an important global health threat. An evidence-based response, tailored to local disease epidemiology in high-burden countries, is key to controlling the global TB epidemic. Reliable surrogate biomarkers that predict key active disease and latent TB infection outcomes are vital to advancing clinical research necessary to ‘End TB’. Well executed longitudinal studies strengthening local research capacity for addressing TB research priorities and advancing biomarker discovery are urgently needed. Methods and analysis The Cohort for Tuberculosis Research by the Indo-US Medical Partnership (CTRIUMPH) study conducted in Byramjee Jeejeebhoy Government Medical College (BJGMC), Pune and National Institute for Research in Tuberculosis (NIRT), Chennai, India, will establish and maintain three prospective cohorts: (1) an Active TB Cohort comprising 800 adults with pulmonary TB, 200 adults with extrapulmonary TB and 200 children with TB; (2) a Household Contact Cohort of 3200 adults and children at risk of developing active disease; and (3) a Control Cohort consisting of 300 adults and 200 children with no known exposure to TB. Relevant clinical, sociodemographic and psychosocial data will be collected and a strategic specimen repository established at multiple time points over 24 months of follow-up to measure host and microbial factors associated with (1) TB treatment outcomes; (2) progression from infection to active TB disease; and (3) Mycobacterium tuberculosis transmission among Indian adults and children. We anticipate CTRIUMPH to serve as a research platform necessary to characterise some relevant aspects of the TB epidemic in India, generate evidence to inform local and global TB control strategies and support novel TB biomarker discovery. Ethics and dissemination This study is approved by the Institutional Review Boards of NIRT, BJGMC and Johns Hopkins University, USA. Study results will be disseminated through peer
Chowdhury, Imran Hussain; Ahmed, Albin Mostaque; Choudhuri, Subhadip; Sen, Aditi; Hazra, Avijit; Pal, Nishith Kumar; Bhattacharya, Basudev; Bahar, Bojlul
Active pulmonary tuberculosis (APTB) is associated with a failure of the host immune system to control the invading Mycobacterium tuberculosis (Mtb). The objective of this study was to quantify and assess the role of serum inflammatory cytokines in active pulmonary tuberculosis patients following anti-tuberculosis drug (ATD) therapy. Blood samples were collected from APTB patients and normal healthy subjects (NHS) (total n=204) at baseline and 2, 4 and 6 months post-therapy and the abundance of serum inflammatory cytokines were measured by cytokine specific ELISA. Compared to NHS, APTB patients at baseline had higher levels of serum pro-inflammatory cytokines IL-12p40 (P<0.001), IFN-γ (P<0.001), TNF-α (P<0.01), IL-1β (P<0.001) and IL-6 (P<0.001) and anti-inflammatory cytokines IL-10 (P<0.001) and TGF-β1 (P<0.001) while there was no change in the level of IL-4. In APTB patients, the serum levels of IFN-γ, TNF-α, IL-6 and TGF-β1 directly relate to the bacterial load while the TNF-α, IL-1β, IL-6 and TGF-β1 relate to radiological severity. At baseline, the IL-6 level in NHS and APTB patients differed most and following ATD therapy, this level rapidly decreased and stabilized by 4-month in APTB patients. It is concluded that a subtle reduction in the serum level of IL-6 of the APTB patients following ATD therapy might play a vital role in immune-protection of the host against Mtb infection and hence the serum IL-6 level can be a useful marker to diagnose the effectiveness of therapy in the patients.
Nathavitharana, Ruvandhi R; Bond, Patricia; Dramowski, Angela; Kotze, Koot; Lederer, Philip; Oxley, Ingrid; Peters, Jurgens A; Rossouw, Chanel; van der Westhuizen, Helene-Mari; Willems, Bart; Ting, Tiong Xun; von Delft, Arne; von Delft, Dalene; Duarte, Raquel; Nardell, Edward; Zumla, Alimuddin
Healthcare workers (HCWs) play a central role in global tuberculosis (TB) elimination efforts but their contributions are undermined by occupational TB. HCWs have higher rates of latent and active TB than the general population due to persistent occupational TB exposure, particularly in settings where there is a high prevalence of undiagnosed TB in healthcare facilities and TB infection control (TB-IC) programmes are absent or poorly implemented. Occupational health programmes in high TB burden settings are often weak or non-existent and thus data that record the extent of the increased risk of occupational TB globally are scarce. HCWs represent a limited resource in high TB burden settings and occupational TB can lead to workforce attrition. Stigma plays a role in delayed diagnosis, poor treatment outcomes and impaired well-being in HCWs who develop TB. Ensuring the prioritization and implementation of TB-IC interventions and occupational health programmes, which include robust monitoring and evaluation, is critical to reduce nosocomial TB transmission to patients and HCWs. The provision of preventive therapy for HCWs with latent TB infection (LTBI) can also prevent progression to active TB. Unlike other patient groups, HCWs are in a unique position to serve as agents of change to raise awareness, advocate for necessary resource allocation and implement TB-IC interventions, with appropriate support from dedicated TB-IC officers at the facility and national TB programme level. Students and community health workers (CHWs) must be engaged and involved in these efforts. Nosocomial TB transmission is an urgent public health problem and adopting rights-based approaches can be helpful. However, these efforts cannot succeed without increased political will, supportive legal frameworks and financial investments to support HCWs in efforts to decrease TB transmission.
Streltsova, O S; Krupin, V N; Yunusova, K E; Mamonov, M V
Genitourinary tract is the second most common site where extrapulmonary tuberculosis (TB) occurs. Genitourinary TB is notable for a latent clinical course and difficult diagnosis. The paper presents clinical observations of two patients treated in a urology department of a general public hospital. One of them was diagnosed with tuberculosis of the prostate, MTB+. In the other, TB of the prostate was suspected based on pathologic assessment of the surgical specimen after surgery for prostate cancer.
Corrêa, Michelle Fidelis; Fernandes, João Paulo-dos Santos
Tuberculosis (TB) is an infectious diseases responsible for thousands of deaths worldwide. Due to the use of antimycobacterial drugs, TB prevalence seemed to be controlled, but with the appearance of resistant tuberculosis cases, the concern about the disease had become significant again, as well as the need for new alternatives to TB treatment. Since pyrazinamide (PZA) is part of the firstline agents in TB treatment, several derivatives of this drug were described, besides pyrazinoic acid (POA) derivatives, the active form of PZA. POA has been used mainly to design prodrugs to be activated by mycobacterial esterases, while PZA derivatives should be activated specifically by the nicotinamidase/ pyrazinamidase (PZAse), or other PZAse-independent pathways. The intention of this paper is to discuss the state of art of PZA and POA derivatives and their activity against Mycobacterium tuberculosis and other mycobacteria, besides the therapeutic potential. Focus was given in prodrugs and derivatives directed to mycobacterial enzymes involved in its activation or mechanism of action.
Hardy, A B; Varma, R; Collyns, T; Moffitt, S J; Mullarkey, C; Watson, J P
NICE (National Institute for Health and Clinical Excellence) guidelines for new entrant tuberculosis (TB) screening recommend chest x ray (CXR) for immigrants from countries with TB incidence >40/10(5), and tuberculin skin test (TST) for people with normal CXR from very high TB prevalence countries. A revised screening policy using first-line QuantiFERON-TB Gold (QFT) in high risk immigrants was piloted in 2007. Initially, TST was offered to immigrants from countries with TB incidence 200-339/10(5), and QFT to those from countries with incidence >340/10(5). When increased resources became available, all immigrants from countries with TB incidence >200/10(5) had QFT. Those with positive QFT were invited for CXR. 1336 immigrant were invited for screening, with a 32% attendance rate. 280 patients had QFT, of which 38% were positive, with <2% being indeterminate. Using the NICE approach, the cost of screening these 280 immigrants would be pound 13,346.75 ( pound 47.67 per immigrant) and would identify 83 cases of latent TB infection (LTBI). Using first-line QFT followed by CXR the cost was pound 9781.82 ( pound 34.94 per immigrant) and identified 105 cases of LTBI. The cost to identify one case of LTBI following NICE guidelines would be pound 160.81 and using the present protocol was pound 93.16. For immigrants from high risk countries QFT blood testing followed by CXR is feasible for TB screening, cheaper than screening using the NICE guideline and identifies more cases of LTBI.
Kendall, Emily A.; Fofana, Mariam O.; Dowdy, David W.
Background Multidrug-resistant tuberculosis (MDR-TB) can be acquired through de novo mutation during TB treatment or through transmission from other individuals with active MDR-TB. Understanding the balance between these two mechanisms is essential when allocating resources for MDR-TB. Methods We constructed a dynamic transmission model of an MDR-TB epidemic, allowing for both treatment-related acquisition and person-to-person transmission of resistance. We used national TB notification data to inform Bayesian estimates of the fraction of each country’s 2013 MDR-TB incidence that resulted from MDR transmission rather than treatment-related MDR acquisition. Findings Global estimates of 3·5% MDR-TB prevalence among new TB notifications and 20·5% among retreatment notifications translate into an estimate that resistance transmission rather than acquisition accounts for a median 96% (95% UR: 68–100%) of all incident MDR-TB, and 61% (16–95%) of incident MDR-TB in previously-treated individuals. The estimated percentage of MDR-TB resulting from transmission varied substantially with different countries’ notification data; for example, we estimated this percentage at 48% (30–75%) of MDR-TB in Bangladesh, versus 99% (91–100%) in Uzbekistan. Estimates were most sensitive to estimates of the transmissibility of MDR strains, the probability of acquiring MDR during tuberculosis treatment, and the responsiveness of MDR TB to first-line treatment. Interpretation Notifications of MDR prevalence from most high-burden settings are most consistent with the vast majority of incident MDR-TB resulting from transmission rather than new treatment-related acquisition of resistance. Merely improving the treatment of drug-susceptible TB is unlikely to greatly reduce future MDR-TB incidence. Improved diagnosis and treatment of MDR-TB – including new tests and drug regimens – should be highly prioritized. PMID:26597127
Bento, Carla F; Empadinhas, Nuno; Mendes, Vítor
Tuberculosis (TB), a chronic infectious disease mainly caused by the tubercle bacillus Mycobacterium tuberculosis, is one of the world's deadliest diseases that has afflicted humanity since ancient times. Although the number of people falling ill with TB each year is declining, its incidence in many developing countries is still a major cause of concern. Upon invading host cells by phagocytosis, M. tuberculosis can replicate within infected cells by arresting the maturation of the phagosome whose function is to target the pathogen for elimination. Host cells have mechanisms of controlling this evasion by inducing autophagy, an elaborate cellular process that targets bacteria for progressive elimination, decreasing bacterial loads within infected cells. In addition, autophagy activation also aids in the control of inflammation, contributing to a more efficient innate immune response against M. tuberculosis. Several innovative TB therapies have been envisaged based on autophagy manipulation, with some of them revealing high potential for future clinical trials and eventual implementation in healthcare systems. Thus, this review highlights the recent advances on the innate immune response regulation by autophagy upon M. tuberculosis infection and the promising new autophagy-based therapies for TB.
Bento, Carla F.; Empadinhas, Nuno
Tuberculosis (TB), a chronic infectious disease mainly caused by the tubercle bacillus Mycobacterium tuberculosis, is one of the world's deadliest diseases that has afflicted humanity since ancient times. Although the number of people falling ill with TB each year is declining, its incidence in many developing countries is still a major cause of concern. Upon invading host cells by phagocytosis, M. tuberculosis can replicate within infected cells by arresting the maturation of the phagosome whose function is to target the pathogen for elimination. Host cells have mechanisms of controlling this evasion by inducing autophagy, an elaborate cellular process that targets bacteria for progressive elimination, decreasing bacterial loads within infected cells. In addition, autophagy activation also aids in the control of inflammation, contributing to a more efficient innate immune response against M. tuberculosis. Several innovative TB therapies have been envisaged based on autophagy manipulation, with some of them revealing high potential for future clinical trials and eventual implementation in healthcare systems. Thus, this review highlights the recent advances on the innate immune response regulation by autophagy upon M. tuberculosis infection and the promising new autophagy-based therapies for TB. PMID:25607549
Tuberculosis (TB) is a deadly infectious disease. Pulmonary TB cases have decreased; yet, extrapulmonary cases such as genitourinary TB have not (Centers for Disease Control and Prevention, 2005). Health care awareness of the clinical features of genitourinary TB is necessary to effectively treat patients with this disease.
Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena
The Portuguese Society of Rheumatology (SPR) and the Portuguese Society of Pulmonology (SPP) have developed guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (AT) in patients with inflammatory joint diseases (IJD), namely rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, treated with tumour necrosis factor alpha (TNF-alpha) antagonists. Due to the high risk of tuberculosis (TB) in patients with IJD, LTBI and AT screening should be performed as soon as possible, ideally at the moment of IJD diagnosis. Even if TB screening was performed at the beginning of the disease, the evaluation should be repeated before starting anti-TNF-alpha therapy. When TB (LTBI orAT) treatment is indicated, it should be performed before the beginning of anti-TNF-alpha therapy. If the IJD activity requires urgent anti-TNF-alpha therapy, these drugs can be started after two months of antituberculosis therapy in AT cases, or after one month in LTBI cases. Chest X-ray is mandatory for all patients. If abnormal, e.g. Gohn complex, the patient should be treated as LTBI; residual lesions require the exclusion of AT and patients with history of untreated or incomplete TB treatment should be treated as LTBI. In cases of suspected active lesions, AT diagnosis should be confirmed and adequate therapy initiated. Tuberculin skin test (TST), with two units of RT23, should be performed in all patients. If induration is less than 5 mm, the test should be repeated after 1 to 2 weeks, on the opposite forearm, and should be considered negative if the result is again inferior to 5 mm. Positive TST implicates LTBI treatment. IfTST is performed in immunosupressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNFalpha therapy, even in the presence of a negative test.
Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena
The Portuguese Society of Rheumatology and the Portuguese Society of Pulmonology have updated the guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (ATB) in patients with inflammatory joint diseases (IJD) that are candidates to therapy with tumour necrosis factor alpha (TNFalpha) antagonists. In order to reduce the risk of tuberculosis (TB) reactivation and the incidence of new infections, TB screening is recommended to be done as soon as possible, ideally at the moment of IJD diagnosis, and patient assessment repeated before starting anti-TNFalpha therapy. Treatment for ATB and LTBI must be done under the care of a TB specialist. When TB treatment is indicated, it should be completed prior to starting anti-TNFalpha therapy. If the IJD activity justifies the need for immediate treatment, anti-TNFalpha therapy can be started two months after antituberculous therapy has been initiated, in the case of ATB, and one month after in the case of LTBI. Chest X-ray is mandatory for all patients. If Gohn s complex is present, the patient should be treated for LTBI; healed lesions require the exclusion of ATB. In cases of suspected active lesions ATB should be excluded/confirmed and adequate therapy initiated. Tuberculin skin test, with two units of RT23, should be performed in all patients. If the induration is <5 mm, the test should be repeated within 1 to 2 weeks, on the opposite forearm, and will be considered negative only if the result is again <5 mm. Positive TST implicates LTBI treatment, unless previous proper treatment was provided. If TST is performed in immunossuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNFalpha therapy, even in the presence of a negative test, after risk/benefit assessment.
Recommendations for the diagnosis and treatment of latent and active tuberculosis in inflammatory joint diseases candidates for therapy with tumor necrosis factor alpha inhibitors - March 2008 update.
The Portuguese Society of Rheumatology and the Portuguese Society of Pulmonology have updated the guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (ATB) in patients with inflammatory joint diseases (IJD) that are candidates to therapy with tumour necrosis factor alpha (TNFα) antagonists. In order to reduce the risk of tuberculosis (TB) reactivation and the incidence of new infections, TB screening is recommended to be done as soon as possible, ideally at the moment of IJD diagnosis, and patient assessment repeated before starting anti-TNFα therapy. Treatment for ATB and LTBI must be done under the care of a TB specialist. When TB treatment is indicated, it should be completed prior to starting anti-TNFα therapy. If the IJD activity justifies the need for immediate treatment, anti-TNFα therapy can be started two months after antituberculous therapy has been initiated, in the case of ATB, and one month after in the case of LTBI. Chest X-ray is mandatory for all patients. If Gohn's complex is present, the patient should be treated for LTBI; healed lesions require the exclusion of ATB. In cases of suspected active lesions, ATB should be excluded/confirmed and adequate therapy initiated. Tuberculin skin test, with two units of RT23, should be performed in all patients. If the induration is <5 mm, the test should be repeated within 1 to 2 weeks, on the opposite forearm, and will be considered negative only if the result is again <5 mm. Positive TST implicates LTBI treatment, unless previous proper treatment was provided. If TST is performed in immunossuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNF-α therapy, even in the presence of a negative test, after risk / benefit assessment. Rev Port Pneumol 2007; XIV (2): 271-283.
Rivas-Santiago, Bruno; Cervantes-Villagrana, Alberto R
It is estimated that there are approximately eight million new cases of active tuberculosis (TB) worldwide annually. There is only 1 vaccine available for prevention: bacillus Calmette-Guérin (BCG). This has variable efficacy and is only protective for certain extrapulmonary TB cases in children, therefore new strategies for the creation of novel vaccines have emerged. One of the promising approaches is the DNA vaccine, used as a direct vaccination or as a prime-boost vaccine. This review describes the experimental data obtained during the design of DNA vaccines for TB.
Kumar, Mani Kant; Kumar, Prashant; Singh, Anjali
Despite over 2.3 million (26% of global burden) cases of tuberculosis (TB) in India the accurate diagnosis of childhood TB remains a major challenge. Children with TB usually have paucibacillary disease and contribute little to disease transmission within the community. Consequently the treatment of children with TB is often not considered a priority by TB control programmes. Adequate and timely assessment of TB infection in childhood could diminish epidemiological burden as underdiagnosed pediatric patients can eventually evolve in to an active state and have the potential to disseminate the etiological agent Mycobacterium tuberculosis, notably increasing this worldwide public health problem. In this review we discuss the most important recent advances in the diagnosis of childhood TB: (1) Symptom-based approaches, (2) novel immune-based approaches, including in vitro interferon-γ IGRA release assays IGRA tests; and (3) bacteriological and molecular methods that are more rapid and/or less expensive than conventional culture techniques for TB diagnosis and/or drug-resistance testing. Recent advances have improved our ability to diagnose latent infection and active TB in children, nevertheless establishing a diagnosis of either latent infection or active disease in HIV-infected children remains a major challenge. PMID:26283820
Background Tuberculosis (TB) in migrants is an ongoing challenge in several low TB incidence countries since a large proportion of TB in these countries occurs in migrants from high incidence countries. To meet these challenges, several countries utilize TB screening programs. The programs attempt to identify and treat those with active and/or infectious stages of the disease. In addition, screening is used to identify and manage those with latent or inactive disease after arrival. Between nations, considerable variation exists in the methods used in migration-associated TB screening. The present study aimed to compare the TB immigration medical examination requirements in selected countries of high immigration and low TB incidence rates. Methods Descriptive study of immigration TB screening programs Results 16 out of 18 eligible countries responded to the written standardized survey and phone interview. Comparisons in specific areas of TB immigration screening programs included authorities responsible for TB screening, the primary objectives of the TB screening program, the yield of detection of active TB disease, screening details and aspects of follow up for inactive pulmonary TB. No two countries had the same approach to TB screening among migrants. Important differences, common practices, common problems, evidence or lack of evidence for program specifics were noted. Conclusions In spite of common goals, there is great diversity in the processes and practices designed to mitigate the impact of migration-associated TB among nations that screen migrants for the disease. The long-term goal in decreasing migration-related introduction of TB from high to low incidence countries remains diminishing the prevalence of the disease in those high incidence locations. In the meantime, existing or planned migration screening programs for TB can be made more efficient and evidenced based. Cooperation among countries doing research in the areas outlined in this study should
Ahn, Jae-Woo; Kim, Kyung-Jin
Tuberculosis is a worldwide epidemic disease caused by Mycobacterium tuberculosis, with an estimated one-third of the human population currently affected. Treatment of this disease with aminoglycoside antibiotics has become less effective owing to antibiotic resistance. Recent determination of the crystal structure of the M. tuberculosis Rv3168 protein suggests a structure similar to that of Enterococcus faecalis APH(3')-IIIa, and that this protein may be an aminoglycoside phosphotransferase. To determine whether Rv3168 confers antibiotic resistance against kanamycin, we performed dose-response antibiotic resistance experiments using kanamycin. Expression of the Rv3168 protein in Escherichia coli conferred antibiotic resistance against 100 μM kanamycin, a concentration that effected cell growth arrest in the parental E. coli strain and an E. coli strain expressing the Rv3168(D249A) mutant, in which the catalytic Asp249 residue was mutated to alanine. Furthermore, we detected phosphotransferase activity of Rv3168 against kanamycin as a substrate. Moreover, docking simulation of kanamycin into the Rv3168 structure suggests that kanamycin fits well into the substrate binding pocket of the protein, and that the phosphorylation-hydroxyl-group of kanamycin was located at a position similar to that in E. faecalis APH(3')-IIIa. On the basis of these results, we suggest that the Rv3168 mediates kanamycin resistance in M. tuberculosis, likely through phosphotransferase targeting of kanamycin.
Phillips, Bonnie L; Mehra, Smriti; Ahsan, Muhammad H; Selman, Moises; Khader, Shabaana A; Kaushal, Deepak
Mycobacterium tuberculosis (MTB) is a highly successful pathogen because of its ability to persist in human lungs for long periods of time. MTB modulates several aspects of the host immune response. Lymphocyte-activation gene 3 (LAG3) is a protein with a high affinity for the CD4 receptor and is expressed mainly by regulatory T cells with immunomodulatory functions. To understand the function of LAG3 during MTB infection, a nonhuman primate model of tuberculosis, which recapitulates key aspects of natural human infection in rhesus macaques (Macaca mulatta), was used. We show that the expression of LAG3 is highly induced in the lungs and particularly in the granulomatous lesions of macaques experimentally infected with MTB. Furthermore, we show that LAG3 expression is not induced in the lungs and lung granulomas of animals exhibiting latent tuberculosis infection. However, simian immunodeficiency virus-induced reactivation of latent tuberculosis infection results in an increased expression of LAG3 in the lungs. This response is not observed in nonhuman primates infected with non-MTB bacterial pathogens, nor with simian immunodeficiency virus alone. Our data show that LAG3 was expressed primarily on CD4(+) T cells, presumably by regulatory T cells but also by natural killer cells. The expression of LAG3 coincides with high bacterial burdens and changes in the host type 1 helper T-cell response.
Moses, Mark W.; Zwerling, Alice; Cattamanchi, Adithya; Denkinger, Claudia M.; Banaei, Niaz; Kik, Sandra V.; Metcalfe, John; Pai, Madhukar; Dowdy, David
Healthcare workers (HCWs) in low-incidence settings are often serially tested for latent TB infection (LTBI) with the QuantiFERON-TB Gold In-Tube (QFT) assay, which exhibits frequent conversions and reversions. The clinical impact of such variability on serial testing remains unknown. We used a microsimulation Markov model that accounts for major sources of variability to project diagnostic outcomes in a simulated North American HCW cohort. Serial testing using a single QFT with the recommended conversion cutoff (IFN-g > 0.35 IU/mL) resulted in 24.6% (95% uncertainty range, UR: 23.8–25.5) of the entire population testing false-positive over ten years. Raising the cutoff to >1.0 IU/mL or confirming initial positive results with a (presumed independent) second test reduced this false-positive percentage to 2.3% (95%UR: 2.0–2.6%) or 4.1% (95%UR: 3.7–4.5%), but also reduced the proportion of true incident infections detected within the first year of infection from 76.5% (95%UR: 66.3–84.6%) to 54.8% (95%UR: 44.6–64.5%) or 61.5% (95%UR: 51.6–70.9%), respectively. Serial QFT testing of HCWs in North America may result in tremendous over-diagnosis and over-treatment of LTBI, with nearly thirty false-positives for every true infection diagnosed. Using higher cutoffs for conversion or confirmatory tests (for initial positives) can mitigate these effects, but will also diagnose fewer true infections. PMID:27469388
Moses, Mark W; Zwerling, Alice; Cattamanchi, Adithya; Denkinger, Claudia M; Banaei, Niaz; Kik, Sandra V; Metcalfe, John; Pai, Madhukar; Dowdy, David
Healthcare workers (HCWs) in low-incidence settings are often serially tested for latent TB infection (LTBI) with the QuantiFERON-TB Gold In-Tube (QFT) assay, which exhibits frequent conversions and reversions. The clinical impact of such variability on serial testing remains unknown. We used a microsimulation Markov model that accounts for major sources of variability to project diagnostic outcomes in a simulated North American HCW cohort. Serial testing using a single QFT with the recommended conversion cutoff (IFN-g > 0.35 IU/mL) resulted in 24.6% (95% uncertainty range, UR: 23.8-25.5) of the entire population testing false-positive over ten years. Raising the cutoff to >1.0 IU/mL or confirming initial positive results with a (presumed independent) second test reduced this false-positive percentage to 2.3% (95%UR: 2.0-2.6%) or 4.1% (95%UR: 3.7-4.5%), but also reduced the proportion of true incident infections detected within the first year of infection from 76.5% (95%UR: 66.3-84.6%) to 54.8% (95%UR: 44.6-64.5%) or 61.5% (95%UR: 51.6-70.9%), respectively. Serial QFT testing of HCWs in North America may result in tremendous over-diagnosis and over-treatment of LTBI, with nearly thirty false-positives for every true infection diagnosed. Using higher cutoffs for conversion or confirmatory tests (for initial positives) can mitigate these effects, but will also diagnose fewer true infections.
KATSUDA, NOBUYUKI; HIROSAWA, TOMOYA; REYER, JOSHUA A; HAMAJIMA, NOBUYUKI
ABSTRACT Public health centers (PHCs, hokenjo in Japanese) are local government authorities responsible for public health in Japan. PHCs have an important role in tuberculosis (TB) control. Typically, their responsibilities include 1) the recommendation to admit infectious TB patients to an isolation ward, 2) health checkups with chest X-ray of those in a close contact with infectious TB patients, and 3) public subsidy of medical expenses for TB treatments. Facing the emergence of multi-drug resistant tuberculosis (MDR-TB), the national TB control program was drastically changed; the Japanese version of the Directly Observed Treatment in Short-course (DOTS) strategy was started in 2005. New roles were added to PHCs’ responsibilities; 1) active screening of latent TB infection by interferon gamma release assays for those in a close contact with infectious TB patients, 2) community DOTS to promote treatment adherence to outpatients, 3) cohort analysis of outcomes of TB treatment, and 4) national MDR-TB surveillance. These roles are important in preventing MDR-TB and eliminating TB in Japan. PMID:25797967
On October 29, 2012, Hurricane Sandy struck the U.S. northeast and mid-Atlantic seaboard; the effects of the storm extended to southeastern and midwestern states and to eastern Canada. At the time, 1,899 residents in the most affected areas were undergoing treatment for tuberculosis (TB) disease or infection. To ascertain the operational abilities of state and local TB programs during and after the storm and to determine whether lessons learned from a previous hurricane were effective in ensuring continuity of TB patient care, CDC interviewed staff members at all of the affected state and city TB control programs, including those in areas with power outages and flooded streets, tunnels, and subway lines. The interviews determined that continuity of care for TB patients in programs affected by Hurricane Sandy was better preserved than it had been during and after Hurricane Katrina in August 2005. This improvement might be attributed to 1) preparedness measures learned from Hurricane Katrina (e.g., preparing line lists of patients, providing patients with as-needed medications, and making back-up copies of patient records in advance of the storm) and 2) less widespread displacement of persons after Hurricane Sandy than occurred after Hurricane Katrina. Maintaining readiness among clinicians and TB control programs to respond to natural disasters remains essential to protecting public health and preserving TB patients' continuity of care.
Liang, Yan; Wang, Ying; Li, Hang; Yang, Yourong; Liu, Jianyang; Yu, Ting; Wu, Xueqiong
The study explored the use of IP-10, MCP-1, and IFN-γ as biomarkers to improve the diagnoses of active pulmonary tuberculosis and tuberculous pleurisy. We enrolled 267 individuals, including 134 TB patients, 93 patients with non-tuberculous pulmonary diseases, and 40 healthy controls. Whole bloods were stimulated in vitro with rCFP-10/ESAT-6 protein antigen of Mycobacterium tuberculosis. The levels of IFN-γ, IP-10, and MCP-1 in cultured supernatants of whole bloods were detected by a chemiluminescence immunoassay. A receiver operating characteristic (ROC) curve was drawn to determine the cutoff value for diagnosing TB and to evaluate the diagnostic efficacies of the IFN-γ, IP-10, and MCP-1 for TB. The antigen-specific release of each cytokine, IFN-γ, IP-10, and MCP-1, was significantly higher in the TB groups than in either the non-tuberculous pulmonary disease group (p < 0.001) or the healthy control group (p < 0.001). The ROC curves indicated cutoff values for IFN-γ, IP-10, and MCP-1 at 147.8, 160.4, and 496.4 pg/mL, respectively. The sensitivity, specificity, PPV, NPV, and diagnostic efficiency for IFN-γ were 85.8%, 70.7%, 74.7%, 83.2%, and 78.3%, respectively; for IP-10 were 72.4%, 75.9%, 75.2%, 73.2%, and 74.2%, respectively; and for MCP-1 were 90.3%, 97.0%, 96.8%, 90.8%, and 93.6%, respectively. IFN-γ combined MCP-1 improved the sensitivity to 97.8% compared with IFN-γ (p < 0.001). Our findings indicate high sensitivity and specificity of MCP-1 as novel biomarkers for the diagnosis of active pulmonary tuberculosis and tuberculous pleurisy.
... Tuberculosis Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC). Background and Brief... prevention and control of HIV infection, viral hepatitis, sexually transmitted diseases (STDs), and tuberculosis (TB), as well as for community-based HIV prevention activities, syphilis, and TB...
Jacobson, Karen R
This issue provides a clinical overview of tuberculosis, focusing on screening, prevention, diagnosis, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.
Getahun, Haileyesus; Matteelli, Alberto; Abubakar, Ibrahim; Aziz, Mohamed Abdel; Baddeley, Annabel; Barreira, Draurio; Den Boon, Saskia; Borroto Gutierrez, Susana Marta; Bruchfeld, Judith; Burhan, Erlina; Cavalcante, Solange; Cedillos, Rolando; Chaisson, Richard; Chee, Cynthia Bin-Eng; Chesire, Lucy; Corbett, Elizabeth; Dara, Masoud; Denholm, Justin; de Vries, Gerard; Falzon, Dennis; Ford, Nathan; Gale-Rowe, Margaret; Gilpin, Chris; Girardi, Enrico; Go, Un-Yeong; Govindasamy, Darshini; D Grant, Alison; Grzemska, Malgorzata; Harris, Ross; Horsburgh, C Robert; Ismayilov, Asker; Jaramillo, Ernesto; Kik, Sandra; Kranzer, Katharina; Lienhardt, Christian; LoBue, Philip; Lönnroth, Knut; Marks, Guy; Menzies, Dick; Migliori, Giovanni Battista; Mosca, Davide; Mukadi, Ya Diul; Mwinga, Alwyn; Nelson, Lisa; Nishikiori, Nobuyuki; Oordt-Speets, Anouk; Rangaka, Molebogeng Xheedha; Reis, Andreas; Rotz, Lisa; Sandgren, Andreas; Sañé Schepisi, Monica; Schünemann, Holger J; Sharma, Surender Kumar; Sotgiu, Giovanni; Stagg, Helen R; Sterling, Timothy R; Tayeb, Tamara; Uplekar, Mukund; van der Werf, Marieke J; Vandevelde, Wim; van Kessel, Femke; van't Hoog, Anna; Varma, Jay K; Vezhnina, Natalia; Voniatis, Constantia; Vonk Noordegraaf-Schouten, Marije; Weil, Diana; Weyer, Karin; Wilkinson, Robert John; Yoshiyama, Takashi; Zellweger, Jean Pierre; Raviglione, Mario
Latent tuberculosis infection (LTBI) is characterised by the presence of immune responses to previously acquired Mycobacterium tuberculosis infection without clinical evidence of active tuberculosis (TB). Here we report evidence-based guidelines from the World Health Organization for a public health approach to the management of LTBI in high risk individuals in countries with high or middle upper income and TB incidence of <100 per 100 000 per year. The guidelines strongly recommend systematic testing and treatment of LTBI in people living with HIV, adult and child contacts of pulmonary TB cases, patients initiating anti-tumour necrosis factor treatment, patients receiving dialysis, patients preparing for organ or haematological transplantation, and patients with silicosis. In prisoners, healthcare workers, immigrants from high TB burden countries, homeless persons and illicit drug users, systematic testing and treatment of LTBI is conditionally recommended, according to TB epidemiology and resource availability. Either commercial interferon-gamma release assays or Mantoux tuberculin skin testing could be used to test for LTBI. Chest radiography should be performed before LTBI treatment to rule out active TB disease. Recommended treatment regimens for LTBI include: 6 or 9 month isoniazid; 12 week rifapentine plus isoniazid; 3-4 month isoniazid plus rifampicin; or 3-4 month rifampicin alone.
Matteelli, Alberto; Abubakar, Ibrahim; Aziz, Mohamed Abdel; Baddeley, Annabel; Barreira, Draurio; Den Boon, Saskia; Borroto Gutierrez, Susana Marta; Bruchfeld, Judith; Burhan, Erlina; Cavalcante, Solange; Cedillos, Rolando; Chaisson, Richard; Chee, Cynthia Bin-Eng; Chesire, Lucy; Corbett, Elizabeth; Dara, Masoud; Denholm, Justin; de Vries, Gerard; Falzon, Dennis; Ford, Nathan; Gale-Rowe, Margaret; Gilpin, Chris; Girardi, Enrico; Go, Un-Yeong; Govindasamy, Darshini; D. Grant, Alison; Grzemska, Malgorzata; Harris, Ross; Horsburgh Jr, C. Robert; Ismayilov, Asker; Jaramillo, Ernesto; Kik, Sandra; Kranzer, Katharina; Lienhardt, Christian; LoBue, Philip; Lönnroth, Knut; Marks, Guy; Menzies, Dick; Migliori, Giovanni Battista; Mosca, Davide; Mukadi, Ya Diul; Mwinga, Alwyn; Nelson, Lisa; Nishikiori, Nobuyuki; Oordt-Speets, Anouk; Rangaka, Molebogeng Xheedha; Reis, Andreas; Rotz, Lisa; Sandgren, Andreas; Sañé Schepisi, Monica; Schünemann, Holger J.; Sharma, Surender Kumar; Sotgiu, Giovanni; Stagg, Helen R.; Sterling, Timothy R.; Tayeb, Tamara; Uplekar, Mukund; van der Werf, Marieke J.; Vandevelde, Wim; van Kessel, Femke; van't Hoog, Anna; Varma, Jay K.; Vezhnina, Natalia; Voniatis, Constantia; Vonk Noordegraaf-Schouten, Marije; Weil, Diana; Weyer, Karin; Wilkinson, Robert John; Yoshiyama, Takashi; Zellweger, Jean Pierre; Raviglione, Mario
Latent tuberculosis infection (LTBI) is characterised by the presence of immune responses to previously acquired Mycobacterium tuberculosis infection without clinical evidence of active tuberculosis (TB). Here we report evidence-based guidelines from the World Health Organization for a public health approach to the management of LTBI in high risk individuals in countries with high or middle upper income and TB incidence of <100 per 100 000 per year. The guidelines strongly recommend systematic testing and treatment of LTBI in people living with HIV, adult and child contacts of pulmonary TB cases, patients initiating anti-tumour necrosis factor treatment, patients receiving dialysis, patients preparing for organ or haematological transplantation, and patients with silicosis. In prisoners, healthcare workers, immigrants from high TB burden countries, homeless persons and illicit drug users, systematic testing and treatment of LTBI is conditionally recommended, according to TB epidemiology and resource availability. Either commercial interferon-gamma release assays or Mantoux tuberculin skin testing could be used to test for LTBI. Chest radiography should be performed before LTBI treatment to rule out active TB disease. Recommended treatment regimens for LTBI include: 6 or 9 month isoniazid; 12 week rifapentine plus isoniazid; 3–4 month isoniazid plus rifampicin; or 3–4 month rifampicin alone. PMID:26405286
Choi, Sunhwa; Jung, Eunok
A mathematical control model for the transmission dynamics of tuberculosis (TB) in South Korea is developed on the basis of the reported active-TB and relapse-TB incidence data. In this work, optimal control theory is used to propose optimal TB prevention and control strategy and rearrange the government TB budget for the best TB elimination plan. The impact of distancing, case finding, and/or case holding controls are investigated when the number of infected and infectious individuals are minimized, while the intervention costs are kept low. The implementation of optimal control measures shows that the distancing control, such as isolation of infectious people, early TB patient detection, and educational program/campaign for healthy control, is the most effective control factor for the prevention of TB transmission in South Korea.
Pareek, Manish; Greenaway, Christina; Noori, Teymur; Munoz, Jose; Zenner, Dominik
Tuberculosis (TB) causes significant morbidity and mortality in high-income countries with foreign-born individuals bearing a disproportionate burden of the overall TB case burden in these countries. In this review of tuberculosis and migration we discuss the impact of migration on the epidemiology of TB in low burden countries, describe the various screening strategies to address this issue, review the yield and cost-effectiveness of these programs and describe the gaps in knowledge as well as possible future solutions.The reasons for the TB burden in the migrant population are likely to be the reactivation of remotely-acquired latent tuberculosis infection (LTBI) following migration from low/intermediate-income high TB burden settings to high-income, low TB burden countries.TB control in high-income countries has historically focused on the early identification and treatment of active TB with accompanying contact-tracing. In the face of the TB case-load in migrant populations, however, there is ongoing discussion about how best to identify TB in migrant populations. In general, countries have generally focused on two methods: identification of active TB (either at/post-arrival or increasingly pre-arrival in countries of origin) and secondly, conditionally supported by WHO guidance, through identifying LTBI in migrants from high TB burden countries. Although health-economic analyses have shown that TB control in high income settings would benefit from providing targeted LTBI screening and treatment to certain migrants from high TB burden countries, implementation issues and barriers such as sub-optimal treatment completion will need to be addressed to ensure program efficacy.
Chaidir, Lidya; Sengstake, Sarah; de Beer, Jessica; Oktavian, Antonius; Krismawati, Hana; Muhapril, Erfin; Kusumadewi, Inri; Annisa, Jessi; Anthony, Richard; van Soolingen, Dick; Achmad, Tri Hanggono; Marzuki, Sangkot; Alisjahbana, Bachti; van Crevel, Reinout
Mycobacterium tuberculosis genotype distribution is different between West and Central Indonesia, but there are no data on the most Eastern part, Papua. We aimed to identify the predominant genotypes of M. tuberculosis responsible for tuberculosis in coastal Papua, their transmission, and the association with patient characteristics. A total of 199 M. tuberculosis isolates were collected. Spoligotyping was applied to describe the population structure of M. tuberculosis, lineage identification was performed using a combination of lineage-specific markers, and genotypic clusters were identified using a combination of 24-locus-MIRU-VNTR and spoligotyping. A high degree of genetic diversity was observed among isolates based on their spoligopatterns. Strains from modern lineage 4 made up almost half of strains (46.9%), being more abundant than the ancient lineage 1 (33.7%), and modern lineage 2 (19.4%). Thirty-five percent of strains belonged to genotypic clusters, especially strains in the Beijing genotype. Previous TB treatment and mutations associated with drug resistance were more common in patients infected with strains of the Beijing genotype. Papua shows a different distribution of M. tuberculosis genotypes compared to other parts of Indonesia. Clustering and drug resistance of modern strains recently introduced to Papua may contribute to the high tuberculosis burden in this region.
Gorospe, Luis; Ayala-Carbonero, Ana María; Rodríguez-Díaz, Ricardo; García Latorre, Raquel; Muñoz-Molina, Gemma María; Cabañero-Sánchez, Alberto
A 62-year-old woman presented to our hospital with an anterior chest wall swelling. Computed tomography (CT) and magnetic resonance imaging showed findings consistent with an infectious arthritis of the manubriosternal joint, and CT images also demonstrated multiple centrilobular nodules in both lungs, suggesting an infectious bronchiolitis. A CT-guided fine needle aspiration of a presternal mass yielded growth of Mycobacterium tuberculosis. Bronchoalveolar lavage confirmed an active pulmonary tuberculosis. Septic arthritis of the manubriosternal joint is exceedingly rare.
Sanaie, A.; Nasrat, A.; Seddiq, M. K.; Mahmoodi, S. D.; Stevens, R. H.; Creswell, J.
Background In Afghanistan, improving TB case detection remains challenging. In 2014, only half of the estimated incident TB cases were notified, and notifications have decreased since peaking in 2007. Active case finding has been increasingly considered to improve TB case notifications. While access to health services has improved in Afghanistan, it remains poor and many people seeking health services won’t receive proper care. Methods From October 2011 through December 2012 we conducted three separate case finding strategies in six provinces of Afghanistan and measured impact on TB case notification. Systematically screening cough among attendees at 47 health facilities, active household contact investigation of smear-positive index TB patients, and active screening at 15 camps for internally displaced people were conducted. We collected both intervention yield and official quarterly notification data. Additional TB notifications were calculated by comparing numbers of cases notified during the intervention with those notified before the intervention, then adjusting for secular trends in notification. Results We screened 2,022,127 people for TB symptoms during the intervention, tested 59,838 with smear microscopy and detected 5,046 people with smear-positive TB. Most cases (81.7%, 4,125) were identified in health facilities while nearly 20% were found through active case finding. A 56% increase in smear-positive TB notifications was observed between the baseline and intervention periods among the 47 health facilities, where cases detected by all three strategies were notified. Discussion While most people with TB are likely to be identified through health facility screening, there are many people who remain without a proper diagnosis if outreach is not attempted. This is especially true in places like Afghanistan where access to general services is poor. Targeted active case finding can improve the number of people who are detected and treated for TB and can
Since after the first streptomycin 1944 trials, anti-tuberculous chemotherapy research has been focused upon establishing drug combination regimens capable of overcoming drug resistance and amenable to ambulatory treatment in resource strapped countries. The first milestone being the 1959 Madras trial comparing home and sanatorium treatment in South India. Subsequently, the MRC trials led Fox and Mitchison to indicate rifampicin, isoniazid and pyrazinamide as the first line drugs for short course, 6 month, regimens and the 1982 Hong Kong Chest Service trials established intermittent therapy as the ambulatory treatment standard for directly observed therapy (DOT). The rising of the HIV epidemic at the beginning of the 1980s has refuelled tuberculosis spread in Africa and Asia and contributed to the expansion of drug-resistant tuberculosis worldwide making the development of new drugs and drug regimens for ambulatory treatment a top priority. Led by biotechnological advances, molecular biology has been brought into TB laboratory diagnosis for the highly sensitive and specific rapid identification of Mycobacterium tuberculosis in biological samples. The field of immunological diagnosis of TB infection, dominated since the early 1900s by the intradermal tuberculin reaction has been put back in motion by the discovery of M. tuberculosis-specific proteins and peptides, now employed in blood tests of high sensitivity and specificity for the diagnosis of latent TB which may help with the identification of contacts at higher risk of active disease and the eradication of epidemic cases.
Zhao, Ning; Spencer, John; Schmitt, Margaret A; Fisk, John D
Tuberculosis is the leading cause of death from infectious disease worldwide. The low sensitivity, extended processing time, and high expense of current diagnostics are major challenges to the detection and treatment of tuberculosis. Mycobacterium tuberculosis ornithine transcarbamylase (Mtb OTC, Rv1656) has been identified in the urine of patients with active TB infection and is a promising target for point-of-care diagnostics. Specific binding proteins with low nanomolar affinities for Mtb OTC were selected from a phage display library built upon a hyperthermostable Sso7d scaffold. Phage particles displaying Sso7d variants were utilized to generate a sandwich ELISA-based assay for Mtb OTC. The assay response is linear between 2 ng/mL and 125 ng/mL recombinant Mtb OTC and has a limit of detection of 400 pg/mL recombinant Mtb OTC. The assay employing a phage-based detection reagent is comparable to commercially-available antibody-based biosensors. Importantly, the assay maintains functionality at both neutral and basic pH in presence of salt and urea over the range of concentrations typical for human urine. Phage-based diagnostic systems may feature improved physical stability and cost of production relative to traditional antibody-based reagents, without sacrificing specificity and sensitivity.
Gray, Kara; Wood, Nicholas; Gunasekera, Hasantha; Sheikh, Mohammad; Hazelton, Briony; Barzi, Federica; Isaacs, David
Vitamin D deficiency and tuberculosis (TB) are associated in adults, but data in children are scarce. We screened refugee children routinely for vitamin D status and TB. Vitamin D values were significantly lower in latent TB (n = 81) and TB infection (n = 11) than in children without TB (n = 236). We conclude that refugee children with TB have reduced vitamin D levels.
Andronikou, Savvas; Wieselthaler, Nicky
Tuberculosis (TB) can affect any organ in the body. Children are a high-risk group for contracting the disease and pose a constant challenge to clinicians with regard to making a definitive diagnosis. Radiologists are playing a more active role in diagnosing TB, and armed with more accurate diagnostic investigations such as CT and MRI, they must face the cost implications as well as technical limitations. This review aims to guide the reader through the modern imaging techniques useful for diagnosing TB of the thorax, central nervous system and abdomen in children. The more specific features of each modality in the particular anatomical regions are highlighted.
Bourgeois, Annie-Claude; Zulz, Tammy; Soborg, Bolette; Koch, Anders
Background Tuberculosis is highly prevalent in many Arctic areas. Members of the International Circumpolar Surveillance Tuberculosis (ICS-TB) Working Group collaborate to increase knowledge about tuberculosis in Arctic regions. Objective To establish baseline knowledge of tuberculosis surveillance systems used by ICS-TB member jurisdictions. Design Three questionnaires were developed to reflect the different surveillance levels (local, regional and national); all 3 were forwarded to the official representative of each of the 15 ICS-TB member jurisdictions in 2013. Respondents self-identified the level of surveillance conducted in their region and completed the applicable questionnaire. Information collected included surveillance system objectives, case definitions, data collection methodology, storage and dissemination. Results Thirteen ICS-TB jurisdictions [Canada (Labrador, Northwest Territories, Nunavik, Nunavut, Yukon), Finland, Greenland, Norway, Sweden, Russian Federation (Arkhangelsk, Khanty-Mansiysk Autonomous Okrug, Yakutia (Sakha Republic), United States (Alaska)] voluntarily completed the survey – representing 2 local, 7 regional and 4 national levels. Tuberculosis reporting is mandatory in all jurisdictions, and case definitions are comparable across regions. The common objectives across systems are to detect outbreaks, and inform the evaluation/planning of public health programmes and policies. All jurisdictions collect data on confirmed active tuberculosis cases and treatment outcomes; 11 collect contact tracing results. Faxing of standardized case reporting forms is the most common reporting method. Similar core data elements are collected; 8 regions report genotyping results. Data are stored using customized programmes (n=7) and commercial software (n=6). Nine jurisdictions provide monthly, bi-annual or annual reports to principally government and/or scientific/medical audiences. Conclusion This review successfully establishes baseline knowledge
Bourgeois, Annie-Claude; Zulz, Tammy; Soborg, Bolette; Koch, Anders; On Behalf Of The International Circumpolar Surveillance-Tuberculosis Working Group
Background Tuberculosis is highly prevalent in many Arctic areas. Members of the International Circumpolar Surveillance Tuberculosis (ICS-TB) Working Group collaborate to increase knowledge about tuberculosis in Arctic regions. Objective To establish baseline knowledge of tuberculosis surveillance systems used by ICS-TB member jurisdictions. Design Three questionnaires were developed to reflect the different surveillance levels (local, regional and national); all 3 were forwarded to the official representative of each of the 15 ICS-TB member jurisdictions in 2013. Respondents self-identified the level of surveillance conducted in their region and completed the applicable questionnaire. Information collected included surveillance system objectives, case definitions, data collection methodology, storage and dissemination. Results Thirteen ICS-TB jurisdictions [Canada (Labrador, Northwest Territories, Nunavik, Nunavut, Yukon), Finland, Greenland, Norway, Sweden, Russian Federation (Arkhangelsk, Khanty-Mansiysk Autonomous Okrug, Yakutia (Sakha Republic), United States (Alaska)] voluntarily completed the survey - representing 2 local, 7 regional and 4 national levels. Tuberculosis reporting is mandatory in all jurisdictions, and case definitions are comparable across regions. The common objectives across systems are to detect outbreaks, and inform the evaluation/planning of public health programmes and policies. All jurisdictions collect data on confirmed active tuberculosis cases and treatment outcomes; 11 collect contact tracing results. Faxing of standardized case reporting forms is the most common reporting method. Similar core data elements are collected; 8 regions report genotyping results. Data are stored using customized programmes (n=7) and commercial software (n=6). Nine jurisdictions provide monthly, bi-annual or annual reports to principally government and/or scientific/medical audiences. Conclusion This review successfully establishes baseline knowledge on
Kinoshita, Takeru; Yamazaki, Masaaki; Kawazoe, Hiroshi; Hosono, Hideo
Long lasting phosphorescence (LLP) and photostimulated luminescence (PSL) were found in reduced calcium aluminate glasses activated with Tb3+ ions. The LLP from Tb3+ was observed by illuminating the Tb3+ 4f→5d charge transfer band with ultraviolet (UV) 254 nm light, while the PSL was seen by stimulating the UV-illuminated glasses with 633 nm light. The decay curve of the LLP was fitted with a second-order kinetic for the initial period (0
Perley, Casey C.; Frahm, Marc; Click, Eva M.; Dobos, Karen M.; Ferrari, Guido; Stout, Jason E.; Frothingham, Richard
Background Vaccine-induced human antibodies to surface components of Haemophilus influenzae and Streptococcus pneumonia are correlated with protection. Monoclonal antibodies to surface components of Mycobacterium tuberculosis are also protective in animal models. We have characterized human antibodies that bind to the surface of live M. tuberculosis. Methods Plasma from humans with latent tuberculosis (TB) infection (n = 23), active TB disease (n = 40), and uninfected controls (n = 9) were assayed by ELISA for reactivity to the live M. tuberculosis surface and to inactivated M. tuberculosis fractions (whole cell lysate, lipoarabinomannan, cell wall, and secreted proteins). Results When compared to uninfected controls, patients with active TB disease had higher antibody titers to the surface of live M. tuberculosis (Δ = 0.72 log10), whole cell lysate (Δ = 0.82 log10), and secreted proteins (Δ = 0.62 log10), though there was substantial overlap between the two groups. Individuals with active disease had higher relative IgG avidity (Δ = 1.4 to 2.6) to all inactivated fractions. Surprisingly, the relative IgG avidity to the live M. tuberculosis surface was lower in the active disease group than in uninfected controls (Δ = –1.53, p = 0.004). Patients with active disease had higher IgG than IgM titers for all inactivated fractions (ratios, 2.8 to 10.1), but equal IgG and IgM titers to the live M. tuberculosis surface (ratio, 1.1). Higher antibody titers to the M. tuberculosis surface were observed in active disease patients who were BCG-vaccinated (Δ = 0.55 log10, p = 0.008), foreign-born (Δ = 0.61 log10, p = 0.004), or HIV-seronegative (Δ = 0.60 log10, p = 0.04). Higher relative IgG avidity scores to the M. tuberculosis surface were also observed in active disease patients who were BCG-vaccinated (Δ = 1.12, p<0.001) and foreign-born (Δ = 0.87, p = 0.01). Conclusions/Significance Humans
Chapman, Helena J; Armas Pérez, Luisa
The fourth Tuberculosis (TB) Symposium, held during the Cuba Salud 2015 International Convention, highlighted advancements in research on TB and Mycobacterium tuberculosis (Mtb) by interdisciplinary teams from academic and federal institutions in Cuba, Colombia, Mexico, and the Dominican Republic. Delegates focused on the targets presented in the World Health Organization End TB Strategy for 2016-2035 and elaborated on four primary themes: 1) attention to vulnerable populations such as immunocompromised individuals, health care workers, and residents of long-term institutions such as prisons and nursing homes; 2) identification of active and latent TB cases through contact investigations; 3) spread and control of drug-resistant Mtb strains; and 4) advancements in the development of novel vaccines or "booster" immunizations. This international TB forum served as a platform for experts in diverse disciplines in these Latin American countries to discuss challenges faced by TB research and control programs, proposing novel research initiatives and promoting collaborative teamwork strategies for TB elimination. In solidarity, collaborative efforts in TB control require identification of symptomatic individuals, rapid diagnostic testing for TB, drug susceptibility assays on Mtb strains, and management that provide universal and gratuitous access to directly observed short-course therapy.
Lee, Ing-Kit; Yang, Wen-Chou; Liu, Jien-Wei
Twenty-nine adults (mean age, 59.9 +/- 13.5 years) with scrotal tuberculosis (TB) were retrospectively analyzed. The mean interval from emergence of symptoms suggestive of scrotal TB to diagnosis established was 142.44 +/- 227.66 days. Scrotal TB was initially suspected in only five (17.2%) patients, and infection caused by bacteria other than Mycobacterium tuberculosis (55.2%) was the leading presumptive diagnosis. Of 28 patients with chest radiographs available, 7 (25%) disclosed active pulmonary TB, and 9 (32.1%) showed a TB scar. All patients received anti-TB chemotherapy; 20 (69%) additionally underwent surgery. Pathologic examination of resected tissue at therapeutic surgery, biopsy, or polymerase chain reaction assay of urine led to rapid diagnosis of scrotal TB. Although evidence of scrotal TB was easily obtainable, the lack of alertness made clinicians avert from the appropriate diagnostic approaches and rendered a delayed diagnosis. Our report underscores the urgent need for improving clinicians' awareness of scrotal TB.
Riben, P D; Epstein, J B; Mathias, R G
The number of new cases--or incidence--of tuberculosis is increasing in nearly every region of the world. A number of forces have resulted in the increased incidence of TB in developed countries, including the HIV epidemic, homelessness, and emigration from highly endemic regions. Although the number of new cases in Canada is relatively constant, the TB experience in the United States serves as a reminder that this situation could change rapidly. The appearance of multidrug-resistant tuberculosis has added to the urgency of situation. The basic methods of preventing TB transmission include preventing the release of the organism into the air, removing the organism from the air, and preventing the inhalation of the organism. Identifying and appropriately treating every person with active tuberculosis is an extremely important component of the control strategy; adequate ventilation, filtering air, and ultraviolet germicidal irradiation are methods used to remove the organism from the air; and masks and other personal protective devices, such as high-efficiency particulate air filters (HEPA), have been suggested as a means of preventing inhalation of the organism. In addition, identifying new TB infections and using chemoprophylaxis often prevents infection from progressing to active disease. Given the route by which tuberculosis is transmitted, it is necessary for both dentists and allied dental personnel to be aware of the risks they may face in day-to-day practice, and the means by which they can protect themselves and their patients.
Matteelli, Alberto; Sulis, Giorgia; Capone, Susanna; D'Ambrosio, Lia; Migliori, Giovanni Battista; Getahun, Haileyesus
Latent tuberculosis infection (LTBI) affects one third to one fourth of the human population and is the reservoir for a significant proportion of emerging active tuberculosis (TB) cases, especially in low incidence countries. The World Health Organization launched in 2015 the END-TB strategy that aims at TB elimination and promotes, for the first time ever, the management of LTBI. The preventive package, basically consisting of testing and treatment for LTBI in groups at high risk of reactivation, is a mainstay of the first pillar of the strategy, alongside prompt diagnosis and early treatment of both drug-susceptible and drug-resistant TB disease. Testing and treatment for LTBI should be pursued with a programmatic perspective. This implies strong political commitment, adequate funding and an effective monitoring and evaluation system. People living with HIV and children under five years of age who are household contact of a contagious TB cases are primarily targeted in all epidemiological setting. In high resource and low incidence setting, additional at risk populations should also be the target for systematic LTBI testing and treatment. Research is urgently needed to develop diagnostic tests with higher predictive value to identify individuals that progress from infection to disease. Similarly, shorter and safer treatment regimens are needed to make the trade-off between potential benefits and harms more favourable for an increasing proportion of infected individuals.
Hatherell, Hollie-Ann; Didelot, Xavier; Pollock, Sue L.; Tang, Patrick; Crisan, Anamaria; Johnston, James C.; Colijn, Caroline
We report an updated method for inferring the time at which an infectious disease was transmitted between persons from a time-labelled pathogen genome phylogeny. We applied the method to 48 Mycobacterium tuberculosis genomes as part of a real-time public health outbreak investigation, demonstrating that although active tuberculosis (TB) cases were diagnosed through 2013, no transmission events took place beyond mid-2012. Subsequent cases were the result of progression from latent TB infection to active disease, and not recent transmission. This evolutionary genomic approach was used to declare the outbreak over in January 2015. PMID:28348853