Validity of Ziehl-Neelsen and LED Fluorescence Microscopy Technique in the Diagnosis of Mycobacterium Tuberculosis Infection among HIV Patients in Lafia, Nigeria, 2017

Abstract

Tuberculosis (TB) is a public health problem caused by the Mycobacterium tuberculosis complex. An estimated 70% of TB patients living with HIV are from sub-Saharan Africa largely depends on direct smear microscopy light microscopy for TB diagnosis, which has low Sensitivity, especially among HIV patients. Hence, we conducted this study to evaluate the Performance of Auramine O LED Fluorescence microscopy and the Ziehl-Neelsen technique in Tuberculosis among HIV-positive patients. The study was conducted using a cross-sectional design among 107 consecutively selected HIV/AIDS patients with presumptive Tuberculosis attending ART clinic in Dalhatu Araf Specialist Hospital (DASH), Lafia, Nasarawa State. Three samples were collected from each patient in two visits. Each sample was examined using ZN, LED FM, and Gene-Xpert. Data on socio-demographic characteristics was collected from the subject participant. Univariate and bivariate analyses were done using MS Excel and Epi Info. The Sensitivity and Specificity were compared using McNemar’s chi-square. Seventy-three (68%) patients were female, 33 (30.8%) were in the age group 28-32 years, and 61 (56%) were employed. Ziehl-Neelsen and LED fluorescent microscopy respectively yielded 11 (10.3%) and 15 (14.0%) positive results, while Gene-Xpert gave 18 (16.3%). The Sensitivity for direct ZN and LED FM were 61.1% and 83.3 %, respectively (P-value 0.01) with 100% specificity for both methods. LED microscopy has a much higher sensitivity than ZN microscopy and would be a better alternative in the diagnosis of Tuberculosis in high HIV settings where the use and expertise with culture and Gene-Xpert are limited. Keywords: HIV, LED Fluorescence, Sensitivity, Specificity, Ziehl-Neelsen.