COMPARATIVE EVALUATION OF MOLECULAR AND CONVENTIONAL DIAGNOSTIC TECHNIQUES FOR TUBERCULOSIS IN PAKISTAN

Abstract

Tuberculosis (TB) remains a major public health challenge in Pakistan, with delayed and inaccurate diagnosis contributing to continued transmission and treatment failure. This study aimed to comparatively evaluate the diagnostic performance of molecular (GeneXpert MTB/RIF) and conventional (Ziehl–Neelsen smear microscopy and culture) techniques for pulmonary and extrapulmonary TB. A total of 350 suspected TB patients from multiple tertiary care centers across Pakistan were enrolled, and specimens were analyzed using all three diagnostic methods. GeneXpert demonstrated significantly higher sensitivity for both pulmonary (88.5%) and extrapulmonary TB (90%) compared to smear microscopy (61.8% and 40%, respectively), while maintaining high specificity (92% and 95%). ZN smear microscopy, though highly specific, showed limited sensitivity, particularly in extrapulmonary cases. Culture served as the reference standard, confirming the accuracy of molecular testing. Additionally, GeneXpert facilitated rapid detection of rifampicin-resistant TB (6.1% of cases), enabling early intervention for multidrug-resistant TB. These findings support the integration of molecular diagnostics with conventional methods to enhance early detection, reduce underdiagnosis, and improve TB management in Pakistan. A tiered diagnostic approach is recommended, particularly in high-burden and resource-limited settings.