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Background: A delay is evident between the development of new policies on TB diagnostics and their implementation at country level. The Stop TB Partnership would benefit from information from national TB program (NTP) managers on progress towards implementation of new recommendations as well as the opportunities and challenges encountered in the process. Methods and Findings: To solicit information on the introduction of new TB diagnostics at country level, questionnaires were sent out to NTP managers of high-burden TB countries and a subset of managers was interviewed. The results indicate that about 50% of high-burden TB countries are using the TB diagnostic tools newly recommended by the World Health Organization (WHO). Most NTP managers reported that new diagnostics would only be implemented when officially endorsed by the WHO. All countries have plans to adopt newly endorsed diagnostics at reference laboratory level, while approaches to optimize smear microscopy at lower levels of the health service are given less attention. NTP managers reported diverse challenges to the implementation of new diagnostics. Conclusions: More information on the obstacles and advantages of introducing new diagnostic tools should be provided to NTP managers to ensure the rational adoption of new diagnostics. A single recommendation covering the introduction of a package of diagnostic tools might be preferable to NTP managers and facilitate implementation in high-burden TB countries. [ABSTRACT FROM AUTHOR]

The microscopical diagnosis of infectious diseases is an essential medical laboratory service in resource-poor countries. We conducted an external quality assessment (EQA) of peripheral laboratories in southern Ethiopia using a panel of 20 ready-prepared sputum and blood smears containing either no pathogens or locally common pathogens. Microscopists also undertook a colour discrimination test (Farnsworth–Munsell 100 hue test). Twenty microscopists from 10 health centres participated. Their microscopy results were compared with that of the EQA controllers. Their Kappa indices of agreement ranged from 0.1 to 0.89 (mean ± SD: 0.58 ± 0.21). Kappa values were analysed according to microscopists’ colour discrimination ability. The Kappa indices for the correct reading of diagnostic smears were associated with the colour vision ability of the technicians. Our results suggest that routine quality improvement activities may not achieve their desired effect if the colour discrimination abilities of technicians are not considered. [ABSTRACT FROM AUTHOR]

Objective. To describe the yield of smear-microscopy and radiological findings by male and female patients with symptoms of tuberculosis in Abuja, Nigeria. Methods. Patients ≥15 years old with cough for >3 weeks submitted 3 sputum samples for smear microscopy. One specimen was cultured using MGIT-960. All patients had lung X-rays and screened for HIV. Results. were more likely to be smear-positive than females (262/774 [34%] and 137/547 [25%],P < .01), but similar proportions of males and females were culture-positive (437/691 [63%] and 294/495 [59%], P = .09). 317/626 (50.6%) males and 249/419 (59.4%) females were HIV-positive (P < .005). Among culture-positives patients, HIV-infected males were less likely to have positive smears than HIV-negative males (49.2% versus 66%, P = .001). Among females, smear positivity did not vary with HIV (46.4% for HIV-positive and 52.9% for HIV-negative, P = .38). Of 274 culture-confirmed TB cases, 226 (82.5%) had cavities, and 271 (99%) had ≥1 lung areas affected. HIV-positive males were more likely to have lung cavities than HIV-positive females (85% versus 69%, P < .04) and to have ≥3 lung areas affected (P = .03). Conclusion. Differences in the yield of smear-microscopy, culture and X-rays on presentation are due to several factors including HIV coinfection and gender. [ABSTRACT FROM AUTHOR]

Summary: In low-income and middle-income countries, direct (unconcentrated) sputum smear microscopy is the primary method for diagnosing pulmonary tuberculosis. The method is fast, inexpensive, and specific for Mycobacterium tuberculosis in high incidence areas. The main limitations of direct microscopy are its relatively low sensitivity, especially in individuals co-infected with HIV, and variable quality of the test in programme conditions. Thus, there is a need to identify methods to improve the sensitivity of microscopy. Physical and chemical sputum processing methods, including centrifugation, sedimentation, and bleach, have been studied and found to show promise. We did a systematic review to assess the ability of different processing methods to improve the sensitivity of microscopy. By searching many sources, we identified 83 studies. Overall, by comparison with direct smears, the results suggested that centrifugation with any of several chemical methods (including bleach) is more sensitive, that overnight sedimentation preceded by chemical processing is more sensitive, and that specificity is similar. There were insufficient data to determine the value of sputum processing methods in patients with HIV infection. Operational studies are needed to determine whether the increased sensitivity provided by processing methods is sufficient to offset their increased cost, complexity, and potential biohazards, and to examine their feasibility. [Copyright &y& Elsevier]

Summary: Most of the world''s tuberculosis cases occur in low-income and middle-income countries, where sputum microscopy with a conventional light microscope is the primary method for diagnosing pulmonary tuberculosis. A major shortcoming of conventional microscopy is its relatively low sensitivity compared with culture, especially in patients co-infected with HIV. In high-income countries, fluorescence microscopy rather than conventional microscopy is the standard diagnostic method. Fluorescence microscopy is credited with increased sensitivity and lower work effort, but there is concern that specificity may be lower. We did a systematic review to summarise the accuracy of fluorescence microscopy compared with conventional microscopy. By searching many databases and contacting experts, we identified 45 relevant studies. Sensitivity, specificity, and incremental yield were the outcomes of interest. The results suggest that, overall, fluorescence microscopy is more sensitive than conventional microscopy, and has similar specificity. There is insufficient evidence to determine the value of fluorescence microscopy in HIV-infected individuals. The results of this review provide a point of reference, quantifying the potential benefit of fluorescence microscopy, with which the increased cost and technical complexity of the method can be compared to determine the possible value of the method under programme conditions. [Copyright &y& Elsevier]