Author: Mark Mascolini
09 February 2010
Intensified tuberculosis case finding—the usual screening tool for people with HIV, at risk of HIV, or living in close groups—yielded the highest proportion of new diagnoses in antiretroviral therapy (ART) and HIV voluntary counseling and testing (VCT) programs, according to results of a systematic review. Sputum exam detected additional cases of TB in study populations.
Researchers analyzed studies of intensified TB case finding published from January 1994 through April 2009 in high-risk populations. In the 78 identified studies, rates of newly diagnosed TB varied substantially between target populations:
• Population-based surveys: 0.7%
• Contact-tracing studies: 2.2%
• Mines: 2.3%
• Prevention of mother-to-child transmission programs: 2.3%
• Prisons: 2.5%
• Medical and antiretroviral treatment clinics: 8.2%
• Voluntary counseling and testing services: 8.5%
For every 100-case greater national TB rate, intensified case finding identified an additional 1 case per 100 screened people (P = 0.03). Microbiological sputum exam of all people without previous TB symptoms yielded an additional 4 new diagnoses per 100 people screened (P = 0.05).
The studies analyzed did not provide data on use of serial screening, treatment outcomes in people diagnosed with active TB, or cost-effectiveness.
The authors call for “concerted action . . . to develop intensified case finding as an important method for control of tuberculosis.”
Source: Katharina Kranzer, Rein M.G.J. Houben, Judith R. Glynn, Linda-Gail Bekker, Robin Wood, Stephen D. Lawn. Yield of HIV-associated tuberculosis during intensified case finding in resource-limited settings: a systematic review and meta-analysis. Lancet Infectious Diseases. 2010; 10: 93-102.
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