Tuberculosis in antiretroviral treatment programs in lower income countries: availability and use of diagnostics and screening.

In resource-constrained settings, tuberculosis (TB) is a common opportunistic infection and cause of death in HIV-infected persons. TB may be present at the start of antiretroviral therapy (ART), but it is often under-diagnosed. We describe approaches to TB diagnosis and screening of TB in ART programs in low- and middle-income countries

Chest radiograph reading and recording system: evaluation in frontline clinicians in Zambia

Background: In Zambia the vast majority of chest radiographs (CXR) are read by clinical officers who have limited training and varied interpretation experience, meaning lower inter-rater reliability and limiting the usefulness of CXR as a diagnostic tool. In 2010–11, the Zambian Prison Service and Ministry of Health established TB and HIV screening programs in six prisons; screening included digital radiography for all participants. Using front-line clinicians we evaluated sensitivity, specificity and inter-rater agreement for digital CXR interpretation using the Chest Radiograph Reading and Recording System (CRRS). Methods: Digital radiographs were selected from HIV-infected and uninfected inmates who participated in a TB and HIV screening program at two Zambian prisons. Two medical officers (MOs) and two clinical officers (COs) independently interpreted all CXRs. We calculated sensitivity and specificity of CXR interpretations compared to culture as the gold standard and evaluated inter-rater reliability using percent agreement and kappa coefficients. Results: 571 CXRs were included in analyses. Sensitivity of the interpretation “any abnormality” ranged from 50–70 % depending on the reader and the patients’ HIV status. In general, MO’s had higher specificities than COs. Kappa coefficients for the ratings of “abnormalities consistent with TB” and “any abnormality” showed good agreement between MOs on HIV-uninfected CXRs and moderate agreement on HIV-infected CXRs whereas the COs demonstrated fair agreement in both categories, regardless of HIV status. Conclusions: Sensitivity, specificity and inter-rater agreement varied substantially between readers with different experience and training, however the medical officers who underwent formal CRRS training had more consistent interpretations.Medicine, Faculty ofNon UBCRadiology, Department ofReviewedFacult

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Characteristics of 47 adult ART programs from lower income countries and 987 adult patients seen during the study period in the programs participating in the study.

<p>ART, antiretroviral treatment; TB, tuberculosis; SMS: Short Message Service.</p>1<p>followed-up at time of survey.</p>2<p>proportion of adults with previous history of TB before starting ART.</p

Program-level characteristics associated with the availability of sputum smear microscopy, culture, chest X-ray, Xpert MTB/RIF, and tuberculin skin testing (TST) in 47 ART programs treating adults in lower income countries.

<p>ART, antiretroviral treatment; TB, tuberculosis; TST, tuberculin skin test.</p><p>Chi square tests were used to calculate <i>P</i> values.</p>1<p>followed-up at time of survey.</p

Availability and use of tuberculosis (TB) diagnostics in HIV-infected individuals, comparing sites with a cost model of free services to the patients and all other sites with full payment, cost sharing or any other cost model.

<p>Analysis was restricted to sites which contributed patient data and to patients from sites with access to the diagnostics.</p><p>Chi square tests were used to calculate <i>P</i> values.</p

Availability and use of tuberculosis (TB) diagnostics in adult TB patients from 47 ART programs in lower income countries.

<p>The analysis was restricted to patients from sites with access to the diagnostic tools.</p><p>Chi square tests were used to calculate <i>P</i> values.</p