Active tuberculosis case finding and detection of drug resistance among HIV-infected patients: A cross-sectional study in a TB endemic area, Gondar, Northwest Ethiopia

• Type of Material: Article
• Authors: Martha Alemayehu, Gondar University; Baye Gelaw, Gondar University; Ebba Abate, Gondar University; Liya Wassie, Armauer Hansen Research Institute; Yeshambel Belyhun, Gondar University; Shiferaw Bekele, Armauer Hansen Research Institute; Russell Kempker, Emory University; Henry Blumberg, Emory University; Abraham Aseffa, Armauer Hansen Research Institute
• Language: English
• Date: 2014-01-01
• Publisher: Elsevier
• Publication Version: Final Published Version
• Copyright Statement: © 2014 Asian-African Society for Mycobacteriology.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.ijmyco.2014.02.004
• Title of Journal or Parent Work: International Journal of Mycobacteriology
• ISSN: 2212-5531
• Volume: 3
• Issue: 2
• Start Page: 132
• End Page: 138
• Grant/Funding Information: This study was funded by the University of Gondar and Armauer Hansen Research Institute.
• Keywords: HIV; Active case finding; TB; Northwest Ethiopia; Drug resistance
• Research Categories: Health Sciences, General; Biology, Microbiology; Health Sciences, Epidemiology

Abstract

Background: Tuberculosis (TB) patients co-infected with human immunodeficiency virus (HIV) often lack the classic symptoms of pulmonary tuberculosis, making the diagnosis difficult. Current practices in resource-limited settings often indicate that these co-infected patients are diagnosed when they clinically manifest disease symptoms, resulting in a delayed diagnosis and despite continued transmission. The aim of this study is to determine the prevalence of undiagnosed pulmonary tuberculosis cases through active case finding and including multidrug-resistant TB (MDR-TB) among HIV-infected patients. Materials and methods: A total of 250 HIV-infected patients, aged 18years and above were evaluated in a cross-sectional design between February 2012 and November 2012. Socio-demographic and clinical data were collected using a structured questionnaire. Sputum samples were collected from all participants for acid fast bacilli (AFB) direct smear microscopy and Mycobacteria culture. A PCR-based RD9 deletion and genus typing, as well as first-line anti-TB drug susceptibility testing, was performed for all culture-positive isolates. Results: Following active TB case finding, a total of 15/250 (6%) cases were diagnosed as TB cases, of whom 9/250 (3.6%) were detected by both smear microscopy and culture and the remaining 6/250 (2.4%) only by culture. All the 15 isolates were typed through RD9 typing of which 10 were Mycobacterium tuberculosis species; 1 belonged to Mycobacterium genus and 4 isolates were non-tuberculous mycobacteria. The prevalence of undiagnosed pulmonary TB disease among the study participants was 4.4%, which implies the possibility of identifying even more undiagnosed cases through active case finding. A multivariate logistic regression showed a statistically significant association between the presence of pneumonia infection and the occurrence of TB (OR=4.81, 95% CI (1.08-21.43), p=0.04). In addition, all the isolates were sensitive to all first-line anti-TB drugs, except for streptomycin, seen in only one newly diagnosed TB patient, and MDR-TB was not detected. Conclusion: The prevalence of undiagnosed pulmonary TB infection among HIV-infected patients in Gondar was 4.4%. Additionally, the possibility of these undiagnosed TB cases in the community could also pose a risk for the transmission of the disease, particularly among family members. Active screening of known HIV-infected individuals, with at least one TB symptom is recommended, even in persons with opportunistic infections.