Sensitivity of direct smear microscopy for the diagnosis of TB in high HIV prevalent population Nnewi, Nigeria

International Conference and Exhibition on Lung Disorders & Therapeutics

July 13-15, 2015 Baltimore, Maryland, USA

Uzoewulu Ngozi G1, Ibeh I N2, Ofiaeli R O1, Umenyonu N3 and Okonkwo R1

Posters-Accepted Abstracts: J Pulm Respir Med

Abstract :

Background: Diagnosis of tuberculosis (TB) amongst HIV patients is a great challenge due to the low density of Acid Fast bacilli (AFB) in their sputum. Objective: The study was conducted to determine the sensitivity of direct smear microscopy (DSM) for TB diagnosis in HIV endemic setting using culture as a gold standard. Method: Sputum specimen of 550 TB suspects were screened microscopically for AFB using Ziehl-Nielsen method at NAUTH Nnewi and positive samples subjected to culture on Lowenstein-Jensen medium with each patient also screened for HIV status. Result: They comprised of 238 (43%) DSM TB positive cases and 312 (57%) DSM TB negative cases. Out of 238 DSM TB positive cases, 180(33%) were culture positive cases with 12(2.1%) culture negative cases, 13 (2.4%) contaminated specimen, 3 (0.5%) NTM and 30(5.5%) lost specimen resulting in 58 (10.5%) specimen which were excluded from analysis respectively. Among the 180 culture positive TB cases 34 (19%) were HIV-positive patients while 146 (81%) were HIV Negative culture positive TB cases, 109 (61%) males as compared to 71 (39%) females within 21-40 years age group mostly affected. Findings from this study showed that the difference in the detection of PTB between these two methods was statistically significant (p=0.0001), identifying high sensitivity case detection rate of DSM as compared to specificity by culture detection more especially in HIV positive persons. Conclusion: To improve TB case detection for effective treatment, we recommend the use of culture as back up to enhance the specificity and accuracy of DSM especially in HIV positive persons.