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Find video protocols related to scientific articles indexed in Pubmed.
Rapid diagnosis of pediatric mycobacterial lymphadenitis using fine needle aspiration biopsy.
Pediatr. Infect. Dis. J.
PUBLISHED: 11-01-2014
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Diagnosis of tuberculosis in children is challenging and fine needle aspiration biopsy (FNAB) is used worldwide in the diagnosis of palpable masses including peripheral lymphadenopathy. Recent studies of the use of nucleic acid amplification such as the Xpert MTB/RIF test on FNAB in adult patients have shown considerable promise. Xpert MTB/RIF allows for the rapid diagnosis of Mycobacterium tuberculosis and identification of rifampicin susceptibility. Studies to date have been predominantly performed in adults. This study aims to determine the accuracy of Xpert MTB/RIF for the detection of M. tuberculosis complex in FNAB from children with clinically suspected mycobacterial lymphadenitis.
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The spread of carbapenemase-producing bacteria in Africa: a systematic review.
J. Antimicrob. Chemother.
PUBLISHED: 09-28-2014
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Carbapenems are the last line of defence against ever more prevalent MDR Gram-negative bacteria, but their efficacy is threatened worldwide by bacteria that produce carbapenemase enzymes. The epidemiology of bacteria producing carbapenemases has been described in considerable detail in Europe, North America and Asia; however, little is known about their spread and clinical relevance in Africa.
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Urine lipoarabinomannan testing for diagnosis of pulmonary tuberculosis in children: a prospective study.
Lancet Glob Health
PUBLISHED: 05-13-2014
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Urine tests for mycobacterial lipoarabinomannan might be useful for point-of-care diagnosis of tuberculosis in adults with advanced HIV infection, but have not been assessed in children. We assessed the accuracy of urine lipoarabinomannan testing for the diagnosis of pulmonary tuberculosis in HIV-positive and HIV-negative children.
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Mixed Mycobacterium tuberculosis complex infections and false-negative results for rifampin resistance by GeneXpert MTB/RIF are associated with poor clinical outcomes.
J. Clin. Microbiol.
PUBLISHED: 04-30-2014
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The Xpert MTB/RIF (Xpert) assay is becoming a principal screening tool for diagnosing rifampin-resistant Mycobacterium tuberculosis complex (MTBC) infection. However, little is known about the performance of the Xpert assay in infections with both drug-sensitive and drug-resistant strains (mixed MTBC infections). We assessed the performance of the Xpert assay for detecting rifampin resistance using phenotypic drug sensitivity testing (DST) as the reference standard in 370 patients with microbiologically proven pulmonary tuberculosis. Mixed MTBC infections were identified genetically through 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. Logistic regression was used to identify the factors associated with poor (defined as treatment failure, default, and death from any cause) or good (defined as cure or successful treatment completion) clinical outcomes. The analytic sensitivity of the Xpert assay for detecting rifampin resistance was assessed in vitro by testing cultures containing different ratios of drug-sensitive and drug-resistant organisms. Rifampin resistance was detected by the Xpert assay in 52 (14.1%) and by phenotypic DST in 55 (14.9%) patients. Mixed MTBC infections were identified in 37 (10.0%) patients. The Xpert assay was 92.7% (95% confidence interval [CI], 82.4% to 97.9%) sensitive for detecting rifampin resistance and 99.7% (95% CI, 98.3% to 99.9%) specific. When restricted to patients with mixed MTBC infections, Xpert sensitivity was 80.0% (95% CI, 56.3 to 94.3%). False-negative Xpert results (adjusted odds ratio [aOR], 6.6; 95% CI,1.2 to 48.2) and mixed MTBC infections (aOR, 6.5; 95% CI, 2.1 to 20.5) were strongly associated with poor clinical outcome. The Xpert assay failed to detect rifampin resistance in vitro when <90% of the organisms in the sample were rifampin resistant. Our study indicates that the Xpert assay has an increased false-negative rate for detecting rifampin resistance with mixed MTBC infections. In hyperendemic settings where mixed infections are common, the Xpert results might need further confirmation.
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Diagnostic accuracy of a rapid urine lipoarabinomannan test for tuberculosis in HIV-infected adults.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 03-29-2014
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In settings of high HIV prevalence, tuberculosis control and patient management are hindered by lack of accurate, rapid tuberculosis diagnostic tests that can be performed at point-of-care. The Determine TB LAM Ag (TB LAM) test is a lateral flow immunochromatographic test for detection of mycobacterial lipoarabinomannan (LAM) in urine. Our objective was to determine sensitivity and specificity of the TB LAM test for tuberculosis diagnosis.
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Diagnostic accuracy of Xpert MTB/RIF for extrapulmonary tuberculosis specimens: establishing a laboratory testing algorithm for South Africa.
J. Clin. Microbiol.
PUBLISHED: 03-12-2014
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South Africa implemented Xpert MTB/RIF as the initial diagnostic test for pulmonary tuberculosis (TB). Xpert MTB/RIF's accuracy for diagnosing extrapulmonary tuberculosis (EPTB) was investigated. EPTB specimens (n = 7,916) from hospitalized patients received over a 6-month period at a high-throughput TB referral laboratory in Johannesburg were investigated. Large-volume specimens were centrifuged, tissue biopsy specimens homogenized, and all specimens checked for growth of contaminating bacteria on blood agar. Contaminated samples received NALC-NaOH (N-acetyl-l-cysteine-sodium hydroxide) decontamination prior to liquid culture. Residual specimens (volumes > 1 ml) after inoculation of culture (n = 1,175) were tested using the Xpert MTB/RIF sputum protocol. Using culture as the reference, Xpert MTB/RIF's overall sensitivity was 59% (95% confidence interval [95% CI], 53% to 65%) and specificity was 92% (CI, 90% to 94%), with the highest sensitivities of 91% (95% CI, 78% to 97%) for pus, 80% (95% CI, 56% to 94%) for lymph node aspirates, and 51% (95% CI, 44% to 58%) for fluids (ascitic, 59%; pleural, 47%). A difference in sensitivities was noticed between specimens classified as having a thick (87% [95% CI, 76% to 94%]) versus clear (watery) (48% [95% CI, 36% to 61%]) appearance. This was unchanged with traces of blood (52% [95% CI, 44% to 60%]) or precentrifugation (57% [95% CI, 28% to 82%]) among clear specimens. Xpert MTB/RIF generated an additional 124 specimen results that were contaminated by Mycobacterial Growth Indicator Tubes (MGIT; 10.5%) and diagnosed rifampin (RIF) resistance earlier (9.6% [25/260]). Xpert MTB/RIF's performance on EPTB specimens provides very promising results and should be considered for incorporation into national TB guidelines. Xpert MTB/RIF is less affected by contaminating bacteria and reduces laboratory labor and diagnostic delay compared to traditional methods.
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GeneXpert MTB/RIF version G4 for identification of rifampin-resistant tuberculosis in a programmatic setting.
J. Clin. Microbiol.
PUBLISHED: 01-31-2014
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A recent Cochrane review estimated GeneXpert MTB/RIF specificity for rifampin resistance as 98% (95% confidence interval [CI], 97 to 99), based on results from earlier test versions. The measured positive predictive value of the new generation test from programmatic implementation in Cape Town, South Africa, was 99.5% (95% CI, 98.5 to 100), confirming excellent specificity.
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Using Xpert MTB/RIF.
Curr Respir Med Rev
PUBLISHED: 07-12-2013
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Xpert MTB/RIF is an automated real-time polymerase chain reaction test for simultaneous detection of tuberculosis and rifampicin resistance. Xpert MTB/RIF has demonstrated excellent accuracy in clinical evaluation studies, but has reduced sensitivity for detection of smear-negative tuberculosis. Since sample processing and detection are largely automated, Xpert MTB/RIF is potentially suitable for implementation in resource-limited settings. There are, however, a number of practical constraints to the use of Xpert at the point-of-care. Xpert remains a relatively costly test, and clear demonstration of cost-effectiveness will be needed to support efforts to scale up testing in high burden countries.
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Determine TB-LAM lateral flow urine antigen assay for HIV-associated tuberculosis: recommendations on the design and reporting of clinical studies.
BMC Infect. Dis.
PUBLISHED: 07-11-2013
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Detection of the Mycobacterium tuberculosis cell wall antigen lipoarabinomannan (LAM) in urine permits diagnoses of tuberculosis (TB) to be made in HIV-infected patients with advanced immunodeficiency. This can be achieved at the point-of-care within just 30 minutes using the Determine TB-LAM, which is a commercially available, lateral-flow urine strip test assay. The assay has been shown to have useful diagnostic accuracy in patients enrolling in antiretroviral treatment services or in HIV-infected patients requiring admission to hospital medical wards in sub-Saharan Africa. Such patients have high mortality risk and have most to gain from rapid diagnosis of TB and immediate initiation of treatment. However, few studies using this assay have yet been reported and many questions remain concerning the correct use of the assay, interpretation of results, the role of the assay as an add-on test within existing diagnostic algorithms and the types of further studies needed. In this paper we address a series of questions with the aim of informing the design, conduct and interpretation of future studies. Specifically, we clarify which clinical populations are most likely to derive benefit from use of this assay and how patients enrolled in such studies might best be characterised. We describe the importance of employing a rigorous microbiological diagnostic reference standard in studies of diagnostic accuracy and discuss issues surrounding the specificity of the assay in different geographical areas and potential cross-reactivity with non-tuberculous mycobacteria and other organisms. We highlight the importance of careful procedures for urine collection and storage and the critical issue of how to read and interpret the test strips. Finally, we consider how the assay could be used in combination with other assays and outline the types of studies that are required to build the evidence base concerning its use.
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Incremental value of T-SPOT.TB for diagnosis of active pulmonary tuberculosis in children in a high-burden setting: a multivariable analysis.
Thorax
PUBLISHED: 05-14-2013
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Interferon ? release assays (IGRAs) are increasingly used for tuberculosis (TB) infection, but their incremental value beyond patient demographics, clinical signs and conventional tests for active disease has not been evaluated in children.
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A comparison of the efficiency of five different commercial DNA extraction kits for extraction of DNA from faecal samples.
J. Microbiol. Methods
PUBLISHED: 05-08-2013
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Differences in the composition of the gut microbiota have been associated with a range of diseases using culture-independent methods. Reliable extraction of nucleic acid is a key step in identifying the composition of the faecal microbiota. Five widely used commercial deoxyribonucleic acid (DNA) extraction kits (QIAsymphony® Virus/Bacteria Midi Kit (kit QS), ZR Fecal DNA MiniPrep™ (kit Z), QIAamp® DNA Stool Mini Kit (kit QA), Ultraclean® Fecal DNA Isolation Kit (kit U) and PowerSoil® DNA Isolation Kit (kit P)) were evaluated, using human faecal samples. Yield, purity and integrity of total genomic DNA were compared spectrophotometrically and using gel electrophoresis. Three bacteria, commonly found in human faeces were quantified using real time polymerase chain reaction (qPCR) and total bacterial diversity was studied using denaturing gradient gel electrophoresis (DGGE) as well as terminal restriction fragment length polymorphism (T-RFLP). The measurements of DNA yield and purity exhibited variations between the five kits tested in this study. Automated kit QS exhibited the best quality and highest quantity of DNA. All kits were shown to be reproducible with CV values?0.46 for DNA extraction. qPCR results showed that all kits were uniformly efficient for extracting DNA from the selected target bacteria. DGGE and T-RFLP produced the highest diversity scores for DNA extracted using kit Z (H=2.30 and 1.27) and kit QS (H=2.16 and 0.94), which also extracted the highest DNA yields compared to the other kits assessed.
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Xpert MTB/RIF testing of stool samples for the diagnosis of pulmonary tuberculosis in children.
Clin. Infect. Dis.
PUBLISHED: 04-11-2013
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In a pilot accuracy study, stool Xpert testing from 115 children with suspected pulmonary tuberculosis (PTB) detected 8/17 (47%) culture-confirmed tuberculosis cases, including 4/5 (80%) HIV-infected and 4/12 (33%) HIV-uninfected children. Sputum Xpert detected 11/17 (65%) cases. Stool holds promise for PTB diagnosis in HIV-infected children.
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Impact of a novel molecular TB diagnostic system in patients at high risk of TB mortality in rural South Africa (Uchwepheshe): study protocol for a cluster randomised trial.
Trials
PUBLISHED: 02-22-2013
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Tuberculosis control in sub-Saharan Africa has long been hampered by poor diagnostics and weak health systems. New molecular diagnostics, such as the Xpert® MTB/RIF assay, have the potential to improve patient outcomes. We present a cluster randomised trial designed to evaluate whether the positioning of this diagnostic system within the health system has an impact on important patient-level outcomes.
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Outbreak of multi-drug resistant Pseudomonas aeruginosa bloodstream infection in the haematology unit of a South African Academic Hospital.
PLoS ONE
PUBLISHED: 01-08-2013
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To describe an outbreak of multi-resistant Pseudomonas aeruginosa bloodstream infections (MRPA-BSI) that occurred in the haematology ward of a tertiary academic hospital in Cape Town, South Africa, and determine risk factors for acquisition of MRPA-BSI.
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Detection of Streptococcus pneumoniae from Different Types of Nasopharyngeal Swabs in Children.
PLoS ONE
PUBLISHED: 01-01-2013
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A better understanding of the epidemiology of nasopharyngeal carriage of Streptococcus pneumoniae is important to assess the impact of vaccination and the pathogenesis of pneumococcal disease. We compared the recovery of S. pneumoniae from nylon flocked, Dacron and rayon swabs.
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Advances in the diagnosis of pulmonary tuberculosis in HIV-infected and HIV-uninfected children.
J. Infect. Dis.
PUBLISHED: 10-15-2011
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The identification of improved diagnostic tests for tuberculosis has been identified as a global research priority. Over the past decade, there has been renewed interest in the development and validation of novel diagnostic tools for pulmonary tuberculosis that are applicable to resource-poor settings. These techniques are aimed primarily at improving detection of the organism or a specific host immune response. Although most studies have focused on determining the accuracy of novel tests in adults, it is likely they will also have the capacity to significantly improve the diagnosis of childhood tuberculosis. Improving the quality of clinical samples obtained from children with suspected tuberculosis remains an important research priority while awaiting validation of novel diagnostic tests. This review will focus on a number of recent developments for the diagnosis of tuberculosis, with a specific emphasis on the application of these new tests to children in settings where tuberculosis is endemic.
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Xpert® MTB/RIF assay: development, evaluation and implementation of a new rapid molecular diagnostic for tuberculosis and rifampicin resistance.
Future Microbiol
PUBLISHED: 10-01-2011
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Global TB control efforts have been severely hampered by the lack of diagnostic tests that are accurate, simple to use and can be applied at the point of clinical care. This has been further compounded by the widespread inability to test for drug resistance. The Xpert(®) MTB/RIF assay is a rapid molecular assay that can be used close to the point of care by operators with minimal technical expertise, enabling diagnosis of TB and simultaneous assessment of rifampicin resistance to be completed within 2 h. Moreover, this can be accomplished using unprocessed sputum samples as well as clinical specimens from extrapulmonary sites. We review in detail the development of this assay, its evaluation within the laboratory, its utility among adult and pediatric TB suspects, its use as a screening tool for HIV-associated TB and studies of its implementation at the district and sub-district levels in resource-limited settings. Following endorsement by the WHO in 2010, we consider the next steps in the implementation of the assay and its potential impact in high burden settings.
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Xpert MTB/RIF for rapid diagnosis of tuberculous lymphadenitis from fine-needle-aspiration biopsy specimens.
J. Clin. Microbiol.
PUBLISHED: 08-31-2011
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This study demonstrates the excellent diagnostic accuracy of the Xpert MTB/RIF test in patients with tuberculous lymphadenitis. The test sensitivity and specificity were 96.7% (95% confidence interval [CI], 86.6 to 100%) and 88.9% (95% CI, 69.6 to 100%), respectively, and it correctly identified 6/6 (100%) of the cytology smear-negative/culture-positive cases and 1 of 2 (50%) rifampin-resistant cases.
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A multisite assessment of the quantitative capabilities of the Xpert MTB/RIF assay.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 08-13-2011
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The Xpert MTB/RIF is an automated molecular test for Mycobacterium tuberculosis that estimates bacterial burden by measuring the threshold-cycle (Ct) of its M. tuberculosis-specific real-time polymerase chain reaction. Bacterial burden is an important biomarker for disease severity, infection control risk, and response to therapy.
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Accuracy of the Xpert MTB/RIF test for the diagnosis of pulmonary tuberculosis in children admitted to hospital in Cape Town, South Africa: a descriptive study.
Lancet Infect Dis
PUBLISHED: 07-19-2011
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WHO recommends that Xpert MTB/RIF replaces smear microscopy for initial diagnosis of suspected HIV-associated tuberculosis or multidrug-resistant pulmonary tuberculosis, but no data exist for its use in children. We aimed to assess the accuracy of the test for the diagnosis of pulmonary tuberculosis in children in an area with high tuberculosis and HIV prevalences.
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Feasibility, diagnostic accuracy, and effectiveness of decentralised use of the Xpert MTB/RIF test for diagnosis of tuberculosis and multidrug resistance: a multicentre implementation study.
Lancet
PUBLISHED: 04-18-2011
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The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA, USA) can detect tuberculosis and its multidrug-resistant form with very high sensitivity and specificity in controlled studies, but no performance data exist from district and subdistrict health facilities in tuberculosis-endemic countries. We aimed to assess operational feasibility, accuracy, and effectiveness of implementation in such settings.
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Rapid diagnosis of tuberculosis with the Xpert MTB/RIF assay in high burden countries: a cost-effectiveness analysis.
PLoS Med.
PUBLISHED: 04-07-2011
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Xpert MTB/RIF (Xpert) is a promising new rapid diagnostic technology for tuberculosis (TB) that has characteristics that suggest large-scale roll-out. However, because the test is expensive, there are concerns among TB program managers and policy makers regarding its affordability for low- and middle-income settings.
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Screening for HIV-associated tuberculosis and rifampicin resistance before antiretroviral therapy using the Xpert MTB/RIF assay: a prospective study.
PLoS Med.
PUBLISHED: 02-15-2011
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The World Health Organization has endorsed the Xpert MTB/RIF assay for investigation of patients suspected of having tuberculosis (TB). However, its utility for routine TB screening and detection of rifampicin resistance among HIV-infected patients with advanced immunodeficiency enrolling in antiretroviral therapy (ART) services is unknown.
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New specimens and laboratory diagnostics for childhood pulmonary TB: progress and prospects.
Paediatr Respir Rev
PUBLISHED: 10-16-2010
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Childhood pulmonary TB (PTB) is under diagnosed, in part due to difficulties in obtaining microbiological confirmation. However, given the poor specificity of clinical diagnosis, microbiological confirmation and drug susceptibility testing is important in guiding appropriate therapy especially in the context of drug resistant TB. Confirmation is often possible, even in infants and young children, if adequate specimens are collected. Culture yield varies with the severity of illness, specimen type and culture method. Induced sputum is recognised as a safe procedure with a high diagnostic yield. Advances include optimised protocols for smear microscopy and modified culture techniques, such as the Microscopic Observation Drug Susceptibility Assay. Detection of Mycobacterium tuberculosis nucleic acid in respiratory specimens has high specificity but relatively poor sensitivity, particularly for smear negative disease. The recent development of an integrated specimen processing and real-time PCR testing platform for M. tuberculosis and rifampicin resistance is an important advance that requires evaluation in childhood TB.
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Rapid molecular detection of tuberculosis and rifampin resistance.
N. Engl. J. Med.
PUBLISHED: 09-10-2010
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Global control of tuberculosis is hampered by slow, insensitive diagnostic methods, particularly for the detection of drug-resistant forms and in patients with human immunodeficiency virus infection. Early detection is essential to reduce the death rate and interrupt transmission, but the complexity and infrastructure needs of sensitive methods limit their accessibility and effect.
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Strains of Mycobacterium tuberculosis from western Maharashtra, India, exhibit a high degree of diversity and strain-specific associations with drug resistance, cavitary disease, and treatment failure.
J. Clin. Microbiol.
PUBLISHED: 08-18-2010
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We performed spoligotyping of Mycobacterium tuberculosis isolates from 833 systematically sampled pulmonary tuberculosis (TB) patients in urban Mumbai, India (723 patients), and adjacent rural areas in western India (110 patients). The urban cohort consisted of two groups of patients, new cases (646 patients) and first-time treatment failures (77 patients), while only new cases were recruited in the rural areas. The isolates from urban new cases showed 71% clustering, with 168 Manu1, 62 CAS, 22 Beijing, and 30 EAI-5 isolates. The isolates from first-time treatment failures were 69% clustered, with 14 Manu1, 8 CAS, 8 Beijing, and 6 EAI-5 isolates. The proportion of Beijing strains was higher in this group than in urban new cases (odds ratio [OR], 3.29; 95% confidence limit [95% CL], 1.29 to 8.14; P = 0.003). The isolates from rural new cases showed 69% clustering, with 38 Manu1, 7 CAS, and 1 EAI-5 isolate. Beijing was absent in the rural cohort. Manu1 was found to be more common in the rural cohort (OR, 0.67; 95% CL, 0.42 to 1.05; P = 0.06). In total, 71% of isolates were clustered into 58 spoligotypes with 4 predominant strains, Manu1 (26%), CAS (9%), EAI-5 (4%), and Beijing (4%), along with 246 unique spoligotypes. In the isolates from urban new cases, we found Beijing to be associated with multidrug resistance (MDR) (OR, 3.40; 95% CL, 1.20 to 9.62; P = 0.02). CAS was found to be associated with pansensitivity (OR, 1.83; 95% CL, 1.03 to 3.24; P = 0.03) and cavities as seen on chest radiographs (OR, 2.72; 95% CL, 1.34 to 5.53; P = 0.006). We recorded 239 new spoligotypes yet unreported in the global databases, suggesting that the local TB strains exhibit a high degree of diversity.
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Reversion and conversion of Mycobacterium tuberculosis IFN-gamma ELISpot results during anti-tuberculous treatment in HIV-infected children.
BMC Infect. Dis.
PUBLISHED: 05-27-2010
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Recent interest has focused on the potential use of serial interferon gamma (IFN-gamma) release assay (IGRA) measurements to assess the response to anti-tuberculous (TB) treatment. The kinetics of IFN-gamma responses to Mycobacterium tuberculosis (MTB) antigens in HIV-infected children during treatment have not however been previously investigated.
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Diagnosis of pulmonary tuberculosis in children: new advances.
Expert Rev Anti Infect Ther
PUBLISHED: 03-03-2010
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The global burden of childhood pulmonary TB has been underappreciated, in part due to difficulties in obtaining microbiological confirmation of disease. Most HIV-uninfected children can be diagnosed using a combination of clinical and epidemiological features, tuberculin skin testing and chest radiography, as represented in different scoring systems. However, accurate microbiologic diagnosis has become increasingly important for timely use of effective treatment. Mycobacterial culture confirms the diagnosis of TB and provides drug susceptibility data but is not available in most areas with a high TB prevalence. Moreover, culture has poor sensitivity in children who usually have paucibacillary disease. The HIV epidemic has made definitive diagnosis even more challenging due to nonspecific clinical and radiological signs. In high HIV-prevalence areas, scoring systems have been especially variable, lacking sensitivity and specificity. Newer methods for diagnosis are aimed either at detecting the organism or a specific host immune response. Methods for organism detection have focused on collection of better samples, improved culture techniques, molecular methods or antigen detection. Recent advances include the use of sputum induction for obtaining a more reliable specimen, faster and more sensitive culture methods, and rapid detection of the organism and drug resistance based on nucleic acid amplification. Improved methods for detecting a specific host response have largely focused on the use of IFN-g release assays. Even with newer methods, accurately diagnosing childhood TB may be challenging. Greater efforts to obtain a microbiologic diagnosis should be made in children, even in primary care settings. Further research to develop a more accurate, cost-effective and simple diagnostic test for childhood TB is urgently needed.
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MVA-85A, a novel candidate booster vaccine for the prevention of tuberculosis in children and adults.
Curr. Opin. Mol. Ther.
PUBLISHED: 02-09-2010
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MVA-85A, in development by Oxford-Emergent Tuberculosis Consortium Ltd and the EU-funded research program TB-VAC, is a live attenuated viral vaccine expressing the immunodominant tuberculosis (TB) antigen 85A, and is intended for use in a heterologous prime-boost strategy to prevent TB. MVA-85A is highly immunogenic in both animals and humans, eliciting strong polyfunctional CD4+ T-cell responses when administered as a boost following BCG vaccination or when administered to individuals previously exposed to TB. Animal studies have demonstrated trends toward reduced pathology and bacillary burden for animals vaccinated with BCG prime followed by MVA-85A boost compared with BCG alone; however, these positive effects appear to be modest, and interpretation is limited by the small number of animals tested. The vaccine has an excellent safety profile in BCG-naïve, previously BCG-vaccinated and TB-exposed adults, as well as in BCG-vaccinated adolescents and children. At the time of publication, MVA-85A was in a more advanced stage of clinical development than other novel TB vaccine candidates, with a large-scale, proof-of-concept phase IIb clinical trial underway for the determination of safety, immunogenicity and prevention of TB in infants.
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Cardiac arrest following cannabis use: a case report.
Cases J
PUBLISHED: 10-12-2009
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Cannabis, or Marijuana, remains one of the most universally used recreational drugs. Over the last four decades, its popularity has risen considerably as it became easily accessible and relatively affordable. Peak use is amongst the young aged 18 to 25 years, although these figures are now shifting towards earlier teens. A strongly installed culture still regards cannabis a harmless drug, yet as more reports have shown there are considerable adverse cardiovascular events linked with its use.
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Detection of tuberculosis in HIV-infected children using an enzyme-linked immunospot assay.
AIDS
PUBLISHED: 03-17-2009
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To evaluate an enzyme-linked immunospot assay (ELISPOT) for the diagnosis of tuberculosis (TB) in HIV-infected children with suspected TB and to compare the performance of ELISPOT with the tuberculin skin test (TST).
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High levels of multidrug resistant tuberculosis in new and treatment-failure patients from the Revised National Tuberculosis Control Programme in an urban metropolis (Mumbai) in Western India.
BMC Public Health
PUBLISHED: 03-06-2009
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India, China and Russia account for more than 62% of multidrug resistant tuberculosis (MDRTB) globally. Within India, locations like urban metropolitan Mumbai with its burgeoning population and high incidence of TB are suspected to be a focus for MDRTB. However apart from sporadic surveys at watched sites in the country, there has been no systematic attempt by the Revised National Tuberculosis Control Programme (RNTCP) of India to determine the extent of MDRTB in Mumbai that could feed into national estimates. Drug susceptibility testing (DST) is not routinely performed as a part of programme policy and public health laboratory infrastructure, is limited and poorly equipped to cope with large scale testing.
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Rapid genotypic assays to identify drug-resistant Mycobacterium tuberculosis in South Africa.
J. Antimicrob. Chemother.
PUBLISHED: 01-24-2009
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Molecular assays to detect drug resistance in Mycobacterium tuberculosis are more rapid than standard drug susceptibility testing. To evaluate the efficacy of such assays in this setting, the GenoType MTBDRplus assay (HAIN Lifescience) and multiplex allele-specific PCR assays were carried out.
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Comparison of T-SPOT.TB assay and tuberculin skin test for the evaluation of young children at high risk for tuberculosis in a community setting.
Pediatrics
PUBLISHED: 01-02-2009
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We wished to compare the sensitivity of an enzyme-linked immunospot assay (T-SPOT.TB; Oxford Immunotec, Oxford, United Kingdom) and the tuberculin skin test for the detection of tuberculosis infection in very young children being evaluated for active tuberculosis in a rural community setting.
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Modern lineages of Mycobacterium tuberculosis exhibit lineage-specific patterns of growth and cytokine induction in human monocyte-derived macrophages.
PLoS ONE
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Strains of Mycobacterium tuberculosis vary in virulence. Strains that have caused outbreaks in the United States and United Kingdom have been shown to subvert the innate immune response as a potential immune evasion mechanism. There is, however, little information available as to whether these patterns of immune subversion are features of individual strains or characteristic of broad clonal lineages of M. tuberculosis.
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Rapid molecular diagnosis of pulmonary tuberculosis in children using nasopharyngeal specimens.
Clin. Infect. Dis.
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A rapid diagnosis of pediatric pulmonary tuberculosis (PTB) using Xpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) automated testing on induced sputum (IS) is possible, but the capacity for performing IS is limited. The diagnosis using a nasopharyngeal aspirate (NPA), which can be non-invasively obtained, is desirable.
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Advances in childhood tuberculosis - contributions from the University of Cape Town.
S. Afr. Med. J.
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Childhood tuberculosis (TB) is common in high TB burden countries, contributing a substantial proportion to the TB caseload. The HIV epidemic has had a large impact on the incidence, diagnosis and management of childhood TB.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.