Comparison of GeneXpert assay and Fluorescent Microscopy for the Diagnosis of Pulmonary Tuberculosis in Narowal region

Abstract

GeneXpert is attributed as one of the latest technical means for diagnosing Tuberculosis in very short period of time. Objectives: To evaluate the efficiency of GeneXpert and fluorescent microscopy in the detection of pulmonary tuberculosis (TB); To compare the sensitivity and specificity of GeneXpert and fluorescent microscope in the diagnosis of Mycobacterium tuberculosis Methods: In the present investigation, the diagnostic performance of GeneXpert MTB / RIF for tuberculosis was compared with the performance of light-emitting diode fluorescence microscope in TB samples from Narowal, Pakistan. For this purpose, a total of 299 TB positive specimens were obtained. Among these 54% (n = 160) were categorized to be obtained from male and 46% (n = 139) from female population. Data collected was distributed in 4 age groups; 0-20, 21-40, 41-60, and 61-80, in which the percentage and number of samples were found as 2% (n = 6), 60% (n = 179), 27% (n = 80) and 11% (n = 34), respectively. Results: The parameters including sensitivity and specificity calculated for GeneXpert were 73% and 100%, correspondingly, while the sensitivity and specificity calculated for LED-FM microscope were 43% and 100%, respectively. Conclusions: This indicates that the GeneXpert is more sensitive in detecting MTB in comparison to LED-FM technique. The GeneXpert assay was also found to detect small number of bacillus from samples in comparison to LED-FM method