Prevalence of Tuberculosis Using Xpert MTB/RIF Assay in a Tertiary Hospital Northwest Nigeria

Abstract

Background: A major impediment in the management and control of tuberculosis is the time frame required for accurate diagnosis. Routine microscopy has low sensitivity while culture, which is the gold standard, has a longer turnaround time and biosafety challenges. The Xpert MTb/Rif (Cepheid), on the other hand, is a newer molecular technology aimed at rapidly improving the diagnosis of tuberculosis (Tb), by being used as the initial test in individuals suspected of having multidrug-resistant Tb or HIV associated Tb. The assay is able to amplify the DNA in mycobacterium and detect genetic mutations associated with resistance to the drug rifampicin within two hours. This study aimed to determine the prevalence of tuberculosis in a tertiary hospital in Northwestern Nigeria using Xpert MTb/Rif assay.
Methodology: This was a retrospective laboratory based study conducted at the Ahmadu Bello University Teaching Hospital, Zaria, Nigeria, from July 2015 to July 2017 on one thousand and forty seven (1047) body fluid specimen submitted at the medical microbiology laboratory for processing using the Xpert MTB/Rif assay. Data was recorded and analysed using Microsoft Excel and SPSS version 20.0. Descriptive statistics was done and results represented in charts and tables.
Results: Of the one thousand and forty seven (1047) patients' specimens tested using Xpert MTB/RIF, 94(9%) were positive for Mycobacterium tuberculosis. 19 (20.2%) had HIV/TB co-infection while 4/ (4.3%) had rifampicin resistant tuberculosis.
Conclusion: The prevalence of tuberculosis and Rifampicin resistant tuberculosis as obtained from this study were 9.4% and 4.3% respectively. Xpert MTB/RIF assay is a valuable alternative for diagnosis of drug sensitive and MDR-TB which will enhance early detection and prevent transmission at all levels of health care.