Open AccessTB testing in HIV-positive patients prior to antiretroviral treatment
Author(s) -
Elizabeth Spooner,
Shabashini Reddy,
Siphelele Ntoyanto,
Y Sakadavan,
Tarylee Reddy,
Saajida Mahomed,
Koleka Mlisana,
M Dlamini,
Brodie Daniels,
Nozipho Luthuli,
Noluthando Ngomane,
Photini Kiepiela,
Anna Coutsoudis
Publication year - 2022
Publication title -
the international journal of tuberculosis and lung disease/the international journal of tuberculosis and lung disease. articles traduits en français ...
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.103
H-Index - 110
eISSN - 1815-7920
pISSN - 1027-3719
DOI - 10.5588/ijtld.21.0195
Subject(s) - medicine , lipoarabinomannan , tuberculosis , sputum , point of care testing , human immunodeficiency virus (hiv) , mycobacterium tuberculosis , diagnostic test , antiretroviral treatment , antiretroviral therapy , immunology , pathology , viral load , pediatrics
BACKGROUND: TB diagnosis in patients with HIV is challenging due to the lower sensitivities across tests. Molecular tests are preferred and the Xpert ® MTB/RIF assay has limitations in lower-income settings. We evaluated the performance of loop-mediated isothermal amplification (LAMP) and the lipoarabinomannan (LAM) test in HIV-positive, ART-naïve clinic patients. METHODS: A total of 783 eligible patients were enrolled; three spot sputum samples of 646 patients were tested using TB-LAMP, Xpert, smear microscopy and culture, while 649 patients had TB-LAM testing. Sensitivity, specificity, and negative and positive predictive values were estimated with 95% confidence intervals. RESULTS: Sensitivities for smear microscopy, TB-LAMP and Xpert were respectively 50%, 63% and 74% compared to culture, with specificities of respectively 99.2%, 98.5% and 97.5%. An additional eight were positive on TB-LAM alone. Seventy TB patients (9%) were detected using standard-of-care testing, an additional 27 (3%) were detected using study testing. Treatment was initiated in 57/70 (81%) clinic patients, but only in 56% (57/97) of all those with positive TB tests; 4/8 multidrug-resistant samples were detected using Xpert. CONCLUSION: TB diagnostics continue to miss cases in this high-burden setting. TB-LAMP was more sensitive than smear microscopy, and if followed by culture and drug susceptibility testing as required, can diagnose TB in HIV-positive patients. TB-LAM is a useful add-in test and both tests at the point-of-care would maximise yield.