Abstract

Introduction: Multi-drug resistant tuberculosis is twice more prevalent in HIV/TB co-infected patients. Diagnosis of pulmonary TB among HIV-infected individuals remains a challenge and the need for easy to perform and accurate tests is imperative. The objective of our study was to assess feasibility and effectiveness of the assay in reducing the median time to diagnosis of TB in HIV-infected individuals.

Methods: After approval from the institutional ethics committee, a prospective study was conducted in a tertiary care hospital in Mumbai. Microscopy, culture and Xpert®MTB/RIF assay were performed on specimens collected from 224 HIV positive adults suspected of TB. Overall diagnostic yield and sensitivity were calculated with culture as reference standard. The results were statistically analysed using the Chi-square test.

Results: Microscopy, culture and Xpert®MTB/RIF assay were positive in 16(7.1%), 36(16.07%) and 34(15.17%) cases respectively. Xpert®MTB/RIF assay was effective in giving an additional yield of 8.04% (18/34) over microscopy. Overall sensitivity of the assay was 77.78% (28/36) and specificity was 96.81%(182/188). Rifampicin resistance was detected in 11 out of 34 cases (32.35%) by Xpert®MTB/RIF assay. Median time to detection of TB by Xpert®MTB/RIF assay was 0days, compared to 1day for microscopy and 30days for solid culture.

Conclusions: Xpert®MTB/RIF assay was effective in diagnosis of TB in a significantly high number of HIV-infected individuals who were sputum smear-negative and significantly reduced the median time to diagnosis of TB. The minimal expertise required for performing the assay makes it feasible to implement Xpert®MTB/RIF assay as a routine diagnostic test in a high throughput microbiology laboratory.

Keywords: Tuberculosis; Xpert®MTB/RIF Assay; Median Time; HIV; Effectiveness

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Citation

Citation: Prapti Gilada., et al. “Feasibility and Effectiveness of Xpert^®MTB/RIF Assay in Reducing the Median Time to Diagnosis of Tuberculosis in HIV Infected Patients". Acta Scientific Microbiology 3.2 (2020): 96-103.

Copyright

Copyright: © 2020 Prapti Gilada., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.