Diagnostic Accuracy of Bronchoalveolar LavageGeneExpert in Smear Negative Pulmonary TuberculosisPatients

Abstract

Background: Because of its low bacillary burden, smear-negative pulmonary tuberculosis (TB) presents major diagnosis problems. In such situations, bronchial lavage (BAL) GeneXpert has becomea quick diagnostic tool with possible value. Objectives: Focus ingonits contribution to enhance clinical outcomes and decreaseTB transmission, this study intended to evaluate the diagnostic accuracy of BAL GeneXpert relative to conventional mycobacterial culture. Methods: This cross-sectional validation study used successive sampling, 384 smear-negative pulmonary TBcases. Bronchos copy produced BAL samples were examined using GeneXpert MTB/RIF and mycobacterial culture, the latter actingas the gold standard. Calculated were sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and general accuracy considering all these factors. Receiver operating characteristic (ROC) curve was plotted in which are a under the curve (AUC) was determined. Results: With the sensitivity of 87.9%, specificity of 44.4%, PPV of 90.6%, NPV of 37.5%, and overall accuracy of 81.8% (p < 0.001), Bal GeneXpertshowed AUC of 0.72 and ROC curve showed fair diagnostic ability. Higher diagnosis accuracy (92.9%) was obtained by post-bronchoscope GeneXpert coupled with culture than by GeneXpertby alone. Although BAL GeneXpert has great sensitivity, its limited specificity underlined the need of supplementary diagnostic techniques to lower false-positive findings. Conclusions: BALForsmear-negative pulmonary TB, GeneXpert is a useful diagnostic tool with great dependability and sensitivity in case confirmation. To improve diagnostic accuracy and confidence, nonetheless, itslimited specificity calls for combination with mycobacterial cultureand post-bronchoscope tests. Especially in resource-limited .environments, using GeneXpert in diagnostic algorithms can help to enhance early TB identification and management. Keywords: Bronchoalveolar lavage, Diagnostic accuracy, GeneXpert MTB/RIF, Pulmonary tuberculosis, ROC curve.