Molecular characterisation of Mycobacterium Tuberculosis, clinical isolates obtained in the Khomas region, Windhoek, Namibia

Abstract

According to the Namibia National Tuberculosis Control Programme (NTCP) report of 2008, Namibia has one of the highest TB infection rates in the world with a case notification rate of 748/100,000. Rapid, specific and sensitive diagnosis of Mycobacterium tuberculosis (MTB) is needed for correct TB patient management. One of the aims of this study was thus to compare direct microscopy with two rapid molecular diagnostic tools (viz. GeneXpert MTB/RIF and Hain Genotype® MTBDR plus assay) for the identification of MTB from samples collected from the Khomas Region, Windhoek, Namibia. Only patients with positive TB sputum collected at the clinics and health facilities in the Khomas Region, Windhoek were eligible for the study. Three hundred and eighty-four samples were confirmed acid-fast positive by utilising the auramine staining method. The rifampicin (RIF) resistance profile detected by both molecular techniques was then compared for characterisation of the samples as drug resistant. Lastly, participants completed a survey, which included questions related to demographic and epidemiological data. Demographic data included patient age, gender, region of residence and history of treatment. The data was collected using a structured questionnaire and was captured in an Excel spreadsheet. It was then imported into Statistical Package for Social Sciences (SPSS) Version 25 for data analysis. A memorandum of understanding was also signed with the Namibia Institute of Pathology (NIP) to obtain permission to use their samples and the equipment at their site.