Latent and subclinical tuberculosis in HIV infected patients: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>HIV and tuberculosis (TB) are commonly associated. Identifying latent and asymptomatic tuberculosis infection in HIV-positive patients is important in preventing death and morbidity associated with active TB.</p> <p>Metho...

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Bibliographic Details
Main Authors: Kall Meaghan M, Coyne Katherine M, Garrett Nigel J, Boyd Aileen E, Ashcroft Anthony T, Reeves Iain, Anderson Jane, Bothamley Graham H
Format: Article
Language:English
Published: BMC 2012-05-01
Series:BMC Infectious Diseases
Online Access:http://www.biomedcentral.com/1471-2334/12/107
Description
Summary:<p>Abstract</p> <p>Background</p> <p>HIV and tuberculosis (TB) are commonly associated. Identifying latent and asymptomatic tuberculosis infection in HIV-positive patients is important in preventing death and morbidity associated with active TB.</p> <p>Methods</p> <p>Cross-sectional study of one time use of an interferon-gamma release assay (T-SPOT.<it>TB</it> - immunospot) to detect tuberculosis infection in patients in a UK inner city HIV clinic with a large sub-Saharan population.</p> <p>Results</p> <p>542 patient samples from 520 patients who disclosed their symptoms of TB were tested. Median follow-up was 35 months (range 27-69). More than half (55%) originated from countries with medium or high tuberculosis burden and 57% were women. Antiretroviral therapy was used by 67%; median CD4 count at test was 458 cells/μl. A negative test was found in 452 samples and an indeterminate results in 40 (7.4%) but neither were associated with a low CD4 count. A positive test was found in 10% (50/502) individuals. All patients with positive tests were referred to the TB specialist, 47 (94%) had a chest radiograph and 46 (92%) attended the TB clinic. Two had culture-positive TB and a third individual with features of active TB was treated. 40 started and 38 completed preventive treatment. One patient who completed preventive treatment with isoniazid monotherapy subsequently developed isoniazid-resistant pulmonary tuberculosis. No patient with a negative test has developed TB.</p> <p>Conclusions</p> <p>We found an overall prevalence of latent TB infection of 10% through screening for TB in those with HIV infection and without symptoms, and a further 1% with active disease, a yield greater than typically found in contact tracing. Acceptability of preventive treatment was high with 85% of those with latent TB infection eventually completing their TB chemotherapy regimens. IGRA-based TB screening among HIV-infected individuals was feasible in the clinical setting and assisted with appropriate management (including preventive treatment and therapy for active disease). Follow-up of TB incidence in this group is needed to assess the long-term effects of preventive treatment.</p>
ISSN:1471-2334