Vaccination with Bacille Calmette–Guérin (BCG) is given at birth to protect against tuberculosis (TB) in Pakistan. The country ranks 6th amongst high-burden countries worldwide and has an incidence of 231/100,000 pyopulation. This was a cross-sectional multi-center hospital-based study. TB patients (n = 218) with pulmonary (PTB, n = 120) or extrapulmonary (ETB, 98) were recruited, and the presence of a BCG vaccination scar was documented. Cases were further classified into minimal, moderate and advanced PTB or less severe (L-ETB) or severe disseminated (D-ETB) disease. The association of age, gender and severity of TB infections with BCG vaccination of the individual TB cases was investigated. No difference was found of the BCG vaccination status of PTB and ETB cases, or in relation to age or gender. Patients under 29 years of age comprised the largest group. There were more females with ETB than PTB. The largest group within ETB comprised those with tuberculous lymphadenitis (LNTB, 39%). A significantly greater number of LNTB cases had received BCG vaccinations than had those with pleural (unilateral) TB (p = 0.004), and tuberculous meningitis (p = 0.027) groups. Also, there were more immunized patients with pulmonary as compared with pleural disease (p = 0.001). LNTB represents localized granulomatous disease and the observation of higher vaccination rates in this group suggests that BCG has protected against more severe forms of TB in this high-burden region.

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Cervical lymphadenitis as a result of nontuberculous mycobacteria, otherwise known as scrofula, is a disease occurring almost exclusively in immunocompetent young children. The most frequent mycobacterial species responsible is Mycobacterium avium, but a large number of other species may also be involved. The epidemiology of such disease is revised here, and the impact of different species as causative agents of adenitis is also discussed.

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A large number of potentially pathogenic non-tuberculous mycobacteria (NTM) encountered in the clinical laboratory makes it necessary to identify their species to ensure appropriate treatment. However, labor-intensive conventional methods of speciation are not used in every laboratory, and hence NTM infections are often ignored. Polymerase chain reaction (PCR) restriction analysis (PRA) was applied in this study for early identification and speciation of mycobacterial species on 306 cultures of acid-fast bacilli isolated from patients suspected of suffering from tuberculosis. Mycobacterium tuberculosis was identified in 85.6% of the isolates. The NTM isolated most commonly was Mycobacterium kansasii/gastri group (3.5%), followed by Mycobacterium fortuitum (3.2%). Four of the M. fortuitum were grown from cultures obtained on the same day, but from samples from different patients and were probably laboratory contaminants. Mycobacterium intracellulare and Mycobacterium avium were identified in 2.94% and 2.28% of the isolates, respectively. Three isolates of M. avium and two isolates of M. intracellulare were obtained in repeated cultures from sputum samples of the same patients and were thus pathogenic. A single isolate of Mycobacterium abscessus was obtained from a breast abscess. A rare pathogen Mycobacterium phocaicum was isolated from one patient with epididymitis. However, whether it was the causative agent of epididymitis in this patient remains doubtful. The results of this study highlight the importance of speciation of mycobacteria for appropriate diagnosis and the importance of including molecular assays to augment conventional methods of diagnosis of mycobacterial diseases for rapid identification of NTM so that these potential pathogens are not overlooked in routine diagnostic procedures.

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Increased utilization of cardiovascular implantable electronic devices (CIED) has seen a corresponding rise in related infections. Non-tuberculosis mycobacteria (NTM) are rarely the cause. Treatment involves susceptibilities, antimicrobials, and device removal. This study presents a patient who underwent a biventricular implantable cardioverter defibrillator upgrade with a multi-drug resistant Mycobacterium fortuitum located at the pocket site and a lead infection.

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The present study was an attempt to establish a suitable method for the effective diagnosis of extra-pulmonary tuberculosis in Bangladesh. In this regard, detection of Mycobacterium tuberculosis from 390 different extra-pulmonary specimens was performed by Bright-Field microscopy, light-emitting diode fluorescence microscopy and Lowenstein–Jensen culture methods, followed by an extensive comparison among these methods. M. tuberculosis was detected in 53 cases through the conventional Lowenstein–Jensen culture method; 49 cases were detected under Bright-Field microscope, whereas the light-emitting diode fluorescence microscopy detected 64 cases. Out of 53 culture-positive isolates, 12 were found to be multi-drug resistant. Light-emitting diode fluorescence microscopy was found to be more sensitive and effective than both the Bright-Field microscopy and the Lowenstein–Jensen culture methods. Incidentally, light-emitting diode fluorescence microscopy appeared imperative to detecting the multi-drug resistant tuberculosis.

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Background: Visualized histopathological findings in tissue samples are not specific for tuberculosis while mycobacterial cultures from such specimens have low yields and long turn around times. A rapid, sensitive method is therefore needed for detection of Mycobacterium tuberculosis in paucibacillary tissue samples. Methodology: In this paper, a total of 158 tissue specimens, including 42 culture-positives, were tested for the presence of Mycobacterium tuberculosis by strand displacement amplification of DNA targeting the region of the insertion element IS 6110 and detected by a chemiluminescence based commercial platform (BDProbeTec™ ET System). The amplification results were correlated to histopathology, microscopy and microbiological culture. Results: The strand displacement amplification based assay showed low overall sensitivity (31.5%) but high specificity (97.5%) which varied across various tissue types. Only 35.7% of culture-positive biopsies were positive by the molecular assay. Some discrepancy were attributed to suboptimal performance of the traditional methods. Conclusions: The assay is useful to rule in the disease in common tissue specimens (lung, pleura and lymph node); but less so in other tissue types. The poor sensitivity in tissue specimens necessitates careful interpretation of data generated by the assay in conjunction with a clinical suspicion of tuberculosis for making decision regarding empirical treatment. The complexity of the disease pathology along with the low bacillary load and clumping tendency require selection of more sensitive methods or gene targets.

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This study describes the experience of mammary, testicle and adnexal tuberculosis (TB) diagnosed by histological characteristics in a rural district hospital in Southern Ethiopia over a period of 7 years. During the same period, a total of 5589 TB cases were diagnosed. Fourteen cases of breast TB with a prevalence of 0.25% (95% confidence interval [CI]: 0.14–0.43), 8 cases of testicular TB (prevalence 0.14, [95% CI: 0.06–0.29]) and two ovarian TB (prevalence: 0.035 [95% CI: 0.001–0.15]). The breast, testes and adnexal TB may mimic other conditions. Proper diagnosis is encouraged because the disease is curable with anti-TB drugs.

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Background: Diagnosis of tuberculous pleurisy is difficult and better diagnostic tools are needed. Interferon gamma release assays (IGRAs) are in vitro immunologic diagnostic tests used to identify Mycobacterium TB infections. They cannot differentiate between latent and active infections. As IGRA tests have recently been approved for the differential diagnosis of active TB, the diagnostic accuracy of the latest generation of IGRA were assessed to detect tuberculous pleurisy in this study. Methods: The QuantiFERONTB®-Gold (QFT-G) test was used in pleural fluid from 100 immunocompetent patients (23 patients for the tuberculous group and 77 patients for the non-tuberculous group). Clinical data were recorded. Adenosine deaminase activity (ADA) analysis and TB culture were performed on pleural fluid. Results: The QFT-G in pleural fluid was positive in 10 (43.5%) patients and indeterminate in 13(56.5%) patients in the tuberculous pleurisy group. There was not a single patient with a negative test result in the tuberculous pleurisy group. The ADA levels were detected as 46.2 ± 12.6 in patients with tuberculous pleurisy and18.6 ± 39.8 in patients with non-tuberculous pleurisy. The sensitivity, specificity, positive predictive value and negative predictive value of QFT-G in pleural fluid for tuberculous pleurisy were 43.5%, 54.5%, 30.3% and 100%; and of ADA in pleural fluid (>40IU/ml) for tuberculous pleurisy the results were 82.6%, 96.1%, 90.5% and 92.5% respectively. Conclusion: While the value of the QFT-G test in exclusion of tuberculous pleurisy was found to be higher in this study, its other diagnostic efficiency values were detected to be low. It is recommended that a new cut-off value be established while diagnosing active TB in prospective clinical studies and that it is also essential to do the same for the studies in various regions with high and low prevalence of TB.

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Metacarpal tuberculosis is a rare presentation of the disease; it represents only 1% of all bone sites. The following report documents the case of a 28-year-old female who sought a consultation for a painful right hand following an injury. Radiographs showed a fracture of the distal fifth metacarpal through a lytic lesion. Histology of a biopsy specimen revealed granulomas with caseous necrosis, specific to tuberculosis. The patient experienced a complete recovery with anti-tubercular treatment. This case of an unusual presentation of isolated metacarpal tuberculosis was reported with the intention of highlighting the rarity of this location. It is therefore imperative to bear in mind the possibility of such atypical presentations of tuberculosis when making a rapid and correct diagnosis and prescribing adequate treatment.

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Background: Documentation of structured quality indicators for mycobacteriology laboratories supporting exclusively controlled clinical trials in pulmonary tuberculosis (PTB) is lacking. Objective: To document laboratory indicators for a solid (Lowenstein–Jensen medium) culture system in a mycobacteriology laboratory for a period of 4 years (2007–2010). Methods: The sputum samples, collected from PTB suspects/patients enrolled in clinical trials, were subjected to fluorescence microscopy, culture and drug sensitivity testing (DST). Data was retrospectively collected from TB laboratory registers and computed using pre-formulated Microsoft Office Excel. Laboratory indicators were calculated and analyzed. Results: The number of samples processed in a calendar year varied from 6261 to 10,710. Of the samples processed in a calendar year, specimen contamination (4.8–6.9%), culture positives (78.4–85.1%) among smear positives, smear positives (71.8–79.0%) among culture positive samples, smear negatives among culture negative samples (95.2–96.7%), and average time to report DST results (76–97 days) varied as shown in parentheses. Conclusion: Values of quality indicators in mycobacteriology laboratories supporting exclusively clinical trials of PTB have to be defined and used for meaningful monitoring of laboratories.

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Within the framework of epidemiological surveillance by molecular typing tools conducted in the NRL on multi-resistant strains, the application of spoligotyping on a group of 390 strains consisting of 389 DR-MTB strains and 1 susceptible strain isolated from patients made it possible to detect the presence of 15 strains belonging to the Beijing genotype. All 15 strains were genotyped by MTBDRplus. Among the 15 strains, 11 were typed by RFLP and 9 by MIRU-VNTR. After analysis of the profiles obtained by the software MIRU-VNTRplus, two spoligotypes (st No. 1 and st No. 265) and four RFLP profiles and a complete identity profile by MIRU-VNTR, information collected on patients allowed the research team to detect a family tie among patients of three different families, as well as one nosocomial TB transmission. The percentage of Beijing strains found among the patients in this study was 3.8%; this figure does not reflect the reality because it was calculated from an essay on MDR-TB. To get an idea of the prevalence of Beijing TB strains in this country, a more extensive study is currently being considered.

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Introduction: New drugs against multi-(MDR) and extensively drug (XDR) resistant tuberculosis are urgently needed. While new candidate drugs are being developed, reinvestigation of already approved drugs available for other indications could be of value. The objective of this study is to determine tentative drug susceptibility testing strategies and breakpoints for thioridazine, a well-known and well-tolerated neuroleptic drug, which has been shown to be effective against drug resistant tuberculosis both in vitro and in vivo. Methods: By testing the minimal inhibitory concentration (MIC) on Middlebrook 7H10 media, the wild-type distribution of thioridazine was established for Mycobacterium tuberculosis (n = 51) and this distribution was compared to the MICs of M/XDR strains (n = 67). Results: A tentative epidemiological cut off (ECOFF) of thioridazine at 16 mg/L was suggested. Even though such concentrations are not clinically achievable in serum, thioridazine is concentrated intracellularly and concentrations of only 0.1 mg/L has been shown to kill M. tuberculosis residing inside cells. MICs above the wild-type (MIC>16 mg/L) were found in 4/67 (6%) of the M/XDR strains suggesting that resistance mechanisms against thioridazine may already be present in resistant clinical strains. Conclusions: In view of the difficulties obtaining clinical outcome data for single drugs in the case of tuberculosis since combination therapy is mandatory, the tentative ECOFF may be considered a tentative clinical breakpoint, but the findings should be validated by others. The data from this study strengthens the use of thioridazine as a treatment option for M/XDR tuberculosis, although its proper place in the therapeutic arsenal should ideally be confirmed in clinical trials.

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Presently, clinicians often forget important aspects of fever patterns. This study presents the case of disseminated tuberculosis in a 64-year-old man whose chief complaint was morning fever. He was a kidney transplant patient and presented with productive cough, reverse fever pattern and a nodular pattern in chest radiograph. Clinicians should suspect disseminated tuberculosis in patients who present with reverse fever pattern, especially with compatible radiographic findings.

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