Identification of Mycobacterium tuberculosis and Rifampin Resistance in Pulmonary and Extra-pulmonary Clinical Specimens Using the Gene Xpert MTB/RIF Assay

Background and objectives: Tuberculosis (TB) is a serious public health problem and a significant diagnostic and therapeutic challenge worldwide. Molecular diagnostic techniques are crucial parts of the World Health Organization’s new tuberculosis control strategy. This study aims to identify Mycobacterium tuberculosis and rifampin resistance in pulmonary and extra-pulmonary clinical specimens using the Gene Xpert MTB/RIF assay. Methods: The study was carried out on 220 specimens from pulmonary and extra-pulmonary TB patients that were sent to the Kavosh Laboratory in Gorgan (Iran) during 2018-20. The Gene Xpert MTB / RIF method was applied to detect M. tuberculosis and rifampin resistance. Results: Of 220 specimens, 15 (6.81%) were found to be positive, four (26.6%) of which were related to pulmonary and 11(73.3%) to extra-pulmonary specimens. None of the positive samples was resitant to rifampin according to assay. Conclusion: Our findings demonstrate that the Gene Xpert MTB/RIF is able to accurately detect M. tuberculosis in pulmonary and extra-pulmonary specimens. The accurate and early diagnosis of TB infection allows timely therapeutic intervention, which is beneficial not only for the patient but also for possible contacts.