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Category: Volume 08 Issue 01 January 2020
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Title: Diagnostic Accuracy of Gene Xpert vs Acid Fast Smear in HIV Patients Suspected for Tuberculosis

Authors: Dr Minni Meka, Dr Jagmohan S V, Dr Raveesha A, Dr Niveditha S

 DOI: https://dx.doi.org/10.18535/jmscr/v8i1.15

Abstract

The risk of developing tuberculosis (TB) is found to be 20 times greater in people living with Human immunodeficiency virus (HIV) than among those without HIV infection.

Objective: To evaluate the accuracy of Gene Xpert for detection of MTB in HIV patient suspected for tuberculosis and comparing with conventional acid fast smear examination.

Methodology: The study was conducted in Medicine OPD and Pulmonology OPD of R L Jalappa Hospital, Tamaka, and Kolar. ART center and RNTCP center, SNR Government Hospital.

Study Design: Cross sectional study.

Study Period: 1 year.

Sample Size: 225 subjects

Results: Smear microscopy has Sensitivity 45.03%, Specificity 100%, NPV 11.76% and PPV 100% for pulmonary specimens, Smear microscopy has Sensitivity 16.67%, Specificity 100%, NPV 44.44% and PPV 100% for extra pulmonary specimens. Overall Smear microscopy has Sensitivity 43.35%, Specificity 100%, NPV 16.06% and PPV 100%.Gene Xpert has Sensitivity 87.43%, Specificity 92.86%, NPV 35.14% and PPV 99.40% for pulmonary specimens, Gene Xpert has Sensitivity 83.33%, Specificity 100%, NPV 80% and PPV 100% for extra pulmonary specimens. Overall Smear microscopy has Sensitivity 87.19%, Specificity 95.45%, NPV 44.68% and PPV 99.44%.

Conclusion: The Gene Xpert MTB is a rapid, sensitive and a reliable diagnostic test for TB than smear microscopy in both pulmonary as well as extra pulmonary TB.The results of this study indicate that the implementation of the Gene Xpert (MTB/RIF) assay could dramatically improve the rapid diagnosis of extra pulmonary tuberculosis as well in HIV infected patients.

Keywords:  Smear Microscopy, Xpert MTB, HIV, Pulmonary Tuberculosis, Extra Pulmonary Tuberculosis.

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Corresponding Author

Dr Jagmohan S V

Assc. Professor, Dept. of Pulmonology