Background: Diagnosis of tuberculosis is a challenge on its own, more so in HIV-infected individuals. The Xpert MTB/RIF assay has recently replaced sputum microscopy as the investigation of choice in People living with HIV (PLHIV). The present study aims to compare two methods for the diagnosis of TB in PLHIV: Microscopy, and Xpert MTB/RIF. and to compare with CD4 count

Objective of the Study

1. To compare between efficacy of CBNAAT and sputum microscopy in detection of pulmonary tuberculosis in HIV patients.
2. To detect the prevalence of rifampicin resistance and MDR TB in HIV patients

Methods: Study was conducted on HIV patients consulted at hospitals attached to Bangalore medical college and research institute, during the period of November 1st 2018 to August 30th 2020 were taken for study, considering the inclusion and exclusion criteria. Detailed clinical history, examination and investigations viz, sputum microscopy ,CBNAAT,CD4 count was done for every patients.

Results: After analysis of the data it was found that CBNAAT was more effective in detecting tuberculosis in PLHIV, when compared to conventional sputum microscopy. Sensitivity of CBNAAT was positively correlated with low CD4 count. The prevalence of rifampicin resistance was 11%

Conclusion: In conclusion, when used as a routine screening test among people living with HIV, rapid screening using the Xpert MTB/RIF assay substantially increased case detection, supporting replacement of microscopy as the initial diagnostic tool. The assay also greatly decreased the time to diagnosis of tuberculosis and aids in early identification of Rifampicin-resistant tuberculosis.

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Dr Saicharan G Chitrak

Junior Resident, Department of Internal Medicine, Bangalore Medical College and Research Institute, Bangalore, India