ROLE OF CBNAAT IN RAPID DETECTION OF MYCOBACTERIUM TUBERCULOSIS IN PLHIV IN A HIGHLY PREVALENT STATE

Abstract

D. Pragati Rao1, K. Lakshmi Sowjanya2

Tuberculosis can occur at any stage of HIV disease and it presents differently according to level of immunosuppression. Patients are paucibacillary, involve hilar and mediastinal lymph nodes, lack cavitation and are smear negative. Sputum culture takes 4-8 weeks for mycobacteria to grow, hence a newly launched cartridge based nucleic acid amplification test by WHO offers a promising solution to these challenges in detecting presumptive pulmonary tuberculosis.
AIM OF STUDY
Comparing efficacy of fluorescent microscopy and CBNAAT for diagnosing pulmonary tuberculosis in PLHIV and detecting Rifampicin resistance.
MATERIAL AND METHODS
This study included all HIV infected patients suspected to have tuberculosis, including drug-resistant tuberculosis, coming to our district tuberculosis centre. The patients were enrolled and provided Xpert MTB/RIF. Simultaneously, smear for AFB was done in same patients.
RESULTS
The study was done for 2 months from February to march 2016. Out of 231 HIV positive patients, 59 cases (25.54%) had tuberculosis. Sputum smear for AFB negative and GeneXpert positive were 45(76.27%). 8(13.55%) cases were Rifampicin resistance and 51 (86.44%) were sensitive out of all tuberculosis patients.
CONCLUSION
This study demonstrates the limitations of conventional sputum microscopy. CBNAAT detects more tuberculosis cases in lesser time. Rifampicin resistance is also detected. Hence drug-resistant tuberculosis can be screened. Early treatment of tuberculosis can be addressed with Xpert MTB/RIF testing.

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