Introduction: With an estimated global incidence of 9.6 million cases per year Tuberculosis (TB) counts for the one of the most common infectious disease of the world, India being at the top. There are various methods to detect pulmonary tuberculosis having various limitations of each test, the newest in this line is Cartridge Based Nucleic Acid Amplification Test (CBNAAT). Sputum microscopy is the simplest and one of the older one to detect TB but it has many limitations especially in Patients Living With HIV (PLHIV) who have scarce production of sputum, so we aim to compare the efficacy of CBNAAT to Sputum Microscopy in detecting TB in PLHIV.
Materials and Methods: In this observational descriptive study we studied 161 subjects infected with HIV and having various symptoms suggestive of Pulmonary Tuberculosis. We did both CBNAAT, Sputum microscopy and Sputum culture as gold standard test for diagnosis of TB.
Results: The most common clinical features was cough (71.42%) followed by fever (70%) & loss of appetite (64.28%), with most cases (44.99%) had CD4 count below 200 cells/cumm and 13.57% cases had seen more than 500 cells/cumm CD4. The prevalence of sputum culture positive Tuberculosis in our study was 88/140 (62.85%). The sensitivity, specificity, PPV, NPV, PLR, NLR of Sputum microscopy were 21.59%, 78.85% ,63.33% , 37.27%, 1.020, 0.994(0.674-1.437) respectively. The sensitivity, specificity, PPV, NPV, PLR, NLR of CBNAAT were 81.82% (72.16-89.24), 90.38%, 93.51%, 74.60%, 8.509, 0.2011 (0.0823-0.7823) respectively. There was significantly higher test accuracy for CBNAAT compared to Sputum microscopy [0.95 vs 0.72, mean diff 0.23 (0.096-0.37), p<0.001).
Conclusion: We concluded that CBNAAT is a better modality than sputum microscopy for diagnosis of pulmonary tuberculosis in specially HIV infected patients.
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2022: 6.012
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