Abstract:

Objective: To evaluate the reliability of rifampicin-resistance (RR) detected by different diagnostics as a predictor for multidrug-resistant tuberculosis (MDR-TB). Methods: A retrospective study was performed by searching the Hospital Information System of Henan Chest Hospital. A total of 130 TB patients who had performed MassARRAY assay for drug resistance detection from July 2021 to November 2022 were enrolled. Of these patients, their GeneXpert MTB/RIF assay (Xpert) and phenotypic drug susceptibility testing (pDST) results were collected for comparative analysis. Results: Among the 130 enrolled patients, 37 (28.46%) were reported as RR by MassARRAY, 38 (37.25%) of 102 patients with Xpert-positive result were categorized as RR patients, 22 (45.83%) of the 48 patients who underwent pDST after a positive culture were categorized as RR. Among patients with RR detected in MassARRAY, the proportion of MDR diagnosed by MassARRAY and pDST was 83.78% (31/37) and 90.48% (19/21), respectively. Among RR patients detected by Xpert, the proportion of MDR diagnosed by MassARRAY and pDST was 73.68% (28/38) and 76.00% (19/25), respectively. In patients with RR detected by pDST, the proportion of MDR diagnosed by MassARRAY and pDST was 90.91% (20/22) and 95.23% (20/21), respectively. Among RR patients diagnosed both by MassARRAY and Xpert, 88.89% (24/27) and 88.89% (16/18) were diagnosed as MDR by MassARRAY or pDST, respectively. Among RR patients detected by any method of MassARRAY or Xpert, 72.92% (35/48) and 75.00% (21/28) were reported as MDR by MassARRAY or pDST, respectively. Conclusion: The RR diagnosed by different diagnostics is a reliable indicator of MDR-TB, but the predictive reliability is related to the accuracy of RR diagnosis.

Key words: Rifampicin, Drug resistance, Tuberculosis, resistant to multiple drugs, Evaluation studies