Onsite Performance Verification of DETERMINE^(TM) TB LAM Ag:A Rapid Diagnostic Test for Tuberculosis Screening in Urine

摘要

According to WHO, the rates of smear-negative and extra-pulmonary pulmonary tuberculosis are increasing in high prevalence HIV epidemic areas. Delays in diagnosis of tuberculosis can lead to large excess of mortality. It is extremely important to provide a strong diagnosis tool of tuberculosis if we want to reduce mortality due particularly to TB co-infection in HIV infected people in low-income countries such as Togo. This study aims to assess the performance of Determine? TB LAM Antigen, a rapid diagnostic test (RDT) for tuberculosis. It was an evaluation study, conducted at the National Reference Laboratory for Mycobacteria located at the Sylvanus Olympio University Teaching Hospital in Lomé, Togo from 01 July to 15 November 2017. We performed the assessment onto 100 urine specimens collected from 100 subjects (HIV-infected or not). The test allows qualitative detection of the Lipo Arabinno Mannan (LAM) antigen of Mycobacteria in the urine. Bacilloscopy was chosen as gold standard. Overall, the test Determine? TB LAM presented a sensitivity of 31.25% and a specificity of 95%. In contrast, the sensitivity and specificity of the test were respectively 82.35% and 66.67% in the group of HIV-infected subjects. In HIV non-infected subjects, the sensitivity was 17.46% and the specificity was 100%. Determine? TB LAM Antigen test can help detect TB in HIV-infected people unable to expectorate in our settings.