Analysis of the detection efficacy of Xpert MTB/RIF, Lowenstein–Jensen medium culture, and fluorescence smear microscopy methods for Mycobacterium tuberculosis diagnosis

Objectives: Tuberculosis (TB) remains a major global health threat, necessitating accurate, rapid, and cost-effective diagnostic methods to improve early detection and control of the disease. The traditional methods for detecting Mycobacterium tuberculosis (MTB) in clinical testing are fluorescence smear microscopy (FSM) and LowensteinJensen medium culture (LJMC) methods. With the development of molecular diagnostics, the Xpert MTB/rifampicin assay (Xpert) has become increasingly used. This study compared Xpert with traditional FSM and LJMC using sputum specimens to study the application value in the diagnosis of TB. Methods: A total of 342 examination reports were included. Sputum samples from all study subjects were tested using FSM, LJMC, and Xpert methods. Results: The Xpert method showed a significantly higher positive rate than FSM, and a slightly higher rate than LJMC. Conclusion: Among all sputum samples from suspected or confirmed TB patients, Xpert detected all cases that were positive by FSM, while both Xpert and LJMC missed positives found by each other. FSM also detected a small number of positives not detected by LJMC. Overall, Xpert had the highest positive detection rate, and FSM the lowest. Although FSM is the fastest and least expensive (costing only one-seventh of Xpert), it demonstrated the lowest sensitivity, with its positive rate being roughly half that of Xpert or LJMC.