Published ahead of print on September 10, 2009 Am. J. Respir. Crit. Care Med. 2009, doi:10.1164/rccm.200806-846OC
Submitted on June 6, 2008 HIV Infection does not Affect Active Case Finding of Tuberculosis in South African Gold MinersJames J Lewis1*,1 Aurum Institute for Health Research, Johannesburg, South Africa; London School of Hygiene and Tropical Medicine, London, United Kingdom, 2 Aurum Institute for Health Research, Johannesburg, South Africa, 3 London School of Hygiene and Tropical Medicine, London, United Kingdom * To whom correspondence should be addressed. E-mail: james.lewis{at}lshtm.ac.uk.
Setting: Occupational health centre of a gold mining company in South Africa, where miners undergo annual radiological screening for tuberculosis. Objective: To evaluate methods for active case detection of tuberculosis. Design: A sequential sample of miners attending annual medical examination were screened for tuberculosis using a symptom questionnaire, chest radiograph and two sputum specimens for microscopy and culture. Results: There were 1,955 miners included in this study; all male, median age 41 (range: 20, 61) years. Presence of at least one of a trio of symptoms (new or worsening cough, night sweats or weight loss) had similar sensitivity (29.4%) to either chest X-ray (25.5%) or sputum smear (25.5%). These sensitivities did not differ by HIV status. Presence of one or more elements of the symptom trio and/or new radiological abnormality substantially increased sensitivity to 49.0%. Specificity of the symptom trio was higher in HIV-uninfected (91.8%) than in HIV-infected persons (88.2%; p-value=0.018). Specificity of chest radiography and smear were similar (98.7% and 99.0%, respectively) and did not differ by HIV status (both p-values>0.8). Conclusion: In a population of gold miners who undergo regular radiological screening, the addition of chest radiography to symptom screening substantially improved the sensitivity and positive predictive value. HIV infection did not alter the sensitivity of the screening tool. Key words: Tuberculosis HIV infection case-finding
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