Genexpert MTB/RIF Diagnostic Yield of Mycobacterium tuberculosis and Rifampicin Resistance in Uyo, Nigeria

*Corresponding author: Ekom Ndifreke Edem, Department of Medical Microbiology, University of Uyo Teaching Hospital, Uyo, Nigeria, E-mail: ekomedem@gmail.com Abstract Tuberculosis (TB) is a public health problem worldwide, with the highest mortality and methods used for the laboratory diagnosis of tuberculosis are continually evolving in order to achieve more rapid, less expensive, and accurate results. Though acid-fast staining and culture for mycobacteria remain at the core of any diagnostic algorithm, a 2-hour identification system for Mycobacterium tuberculosis is describe here. This system has significantly increased sensitivity compared to conventional smear microscopy and provides results within a matter of hours compared to weeks for solid culture, which is the current gold standard. This study assessed the diagnostic accuracy of GeneXpert MTB/RIF assay in the diagnosis of TB and MDR-TB in Uyo. Acid fast bacilli test and genexpert assay were used to test one hundred and forty sputum specimens at the TB laboratory, St, Luke’s Hospital, Uyo, Akwa Ibom State. The results showed that GeneXpert had a positivity rate of 22.9% (32/140), which was significantly higher than that AFB smear (19.3%, 27/140). Sputum quantity and type were both significantly associated (p<0.05) with MTB positivity in Xpert MTB/RIF results. Genexpert MTB/RIF detected 1(3.1%) case of rifampicin resistance (also termed MDR-TB) among 32 M. tuberculosis positive samples. In conclusion, the study data provides important hints to formulate an appropriate diagnostic algorithm for pulmonary tuberculosis based on the appearance of sputum samples and also demonstrates that GeneXpert can be used as an initial diagnostic test for tuberculosis detection and rifampicin resistance in patients suspected of having tuberculosis.