GeneXpert MTB-RIF assay as a rapid and effective molecular method for the diagnosis of tuberculosis in Erbil City
Background and objective: Tuberculosis is a major public health problem worldwide, especially in developing countries. The disease poses a massive threat to public health, causing increased morbidity and mortality. Therefore, early detection is essential to reduce the death rate and interrupt transmission. In this study, GeneXpert assay was used for the rapid identification of bacteria, and its sensitivity and specificity were compared with acid fast bacilli staining in both pulmonary and extrapulmonary clinical specimens.
Methods: A total of 115 pulmonary and extrapulmonary samples were collected and diagnosed for tuberculosis detection. Acid fastbacilli, culture, and GeneXpert methods were used for the diagnosis of tuberculosis.
Results: Out of 115 tuberculosis specimens, 70 were acid fast bacilli smear positive, while 97 samples were positive for Mycobacterium tuberculosis by GeneXpert assay. The results indicated a higher sensitivity of GeneXpert assay compared to the acid fastbacillistaining method. The sensitivity of GeneXpert was 91.6%, specificity 50%; positive and negative predictive values were 89.7% and 55.6%, respectively. No significant differences were detected between the Gene Xpert test results and the culture results (P = 0.815), and the total agreement between the tests was 84.3%.
Conclusion: We concluded that the GeneXpert test results is sensitive as culture results for both pulmonary and extrapulmonary specimens. Although culture remains the gold standard for laboratory confirmation of tuberculosis disease, GeneXpert should become standard practice for patients suspected of tuberculosis, and all clinicians and public health tuberculosis programs should have access to molecular testing for tuberculosis to shorten the time of diagnosis.
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