Data from: Tuberculosis in people newly diagnosed with HIV at a large HIV care and treatment center in Northwest Cameroon: burden, comparative screening and diagnostic yields, and patient outcomes

Background Diagnosis of tuberculosis in people living with HIV is
challenging due to non-specific clinical presentations and inadequately
sensitive diagnostic tests. The WHO recommends screening using a clinical
algorithm followed by rapid diagnosis using the Xpert MTB/RIF assay, and
more information is needed to evaluate these recommendations in different
settings. Methods From August 2012 to September 2013, consecutive adults
newly diagnosed with HIV in Bamenda, Cameroon, were screened for TB
regardless of symptoms by smear microscopy and culture; the Xpert MTB/RIF
assay was performed retrospectively. Time to treatment and patient
outcomes were obtained from routine registers. Results Among 1,149 people
enrolled, 940 (82%) produced sputum for lab testing; of these, 68% were
women, the median age was 35 years (IQR, 28-42 years), the median CD4
count was 291cells/µL (IQR, 116-496 cells/µL), and 86% had one or more of
current cough, fever, night sweats, or weight loss. In total, 131 people
(14%, 95% CI, 12-16%) had sputum culture-positive TB. The WHO symptom
screening algorithm had a sensitivity of 92% (95%CI, 86-96%) and
specificity of 15% (95%CI, 12-17%) in this population. Compared to TB
culture, the sensitivity of direct smear microscopy was 25% (95% CI,
18-34%), and the sensitivity of Xpert was 68% (95% CI, 58-76); the
sensitivity of both was higher for people reporting more symptoms. Only
one of 69 people with smear-negative/culture-positive TB was started on TB
treatment prior to culture positivity. Of 71 people with
bacteriologically-confirmed TB and known outcome after 6 months, 13 (17%)
had died, including 11 people with smear-negative TB and 6 people with
both smear and Xpert-negative TB. Conclusions Use of the most sensitive
rapid diagnostic test available is critical in people newly diagnosed with
HIV in this setting to maximize the detection of
bacteriologically-confirmed TB. However, this intervention is not
sufficient alone and should be combined with more comprehensive clinical
diagnosis of TB to improve outcomes.