Abstract:

Objective To retrospectively analyze the drug resistance to rifampicin and isoniazid in 411 cases of pulmonary tuberculosis (PTB) in Longyan City, Fujian Province, and provide a scientific basis for the prevention and treatment of tuberculosis in local areas. Methods From May 12, 2016 to August 17, 2019, 411 PTB patients who admitted to the outpatient department and hospitalized in the Second Hospital of Longyan City, Fujian Province were collected, including 312 patients with initial treatment and 99 patients with retreatment. Resistance to rifampicin and isoniazid and the mutation sites of related resistance gene were detected in 411 clinical isolates of Mycobacterium tuberculosis using gene chip technology, and the results were compared between patients with initial treatment and retreatment. Data were collated and statistically analyzed using Excel 2003 and SPSS 20.0 software, respectively. Comparison of count data was performed using the χ ² test. P<0.05 was considered statistically significant. Results In 411 PTB patients, the mutation rate of rifampicin and isoniazid at any site of patients with initial treatment was significantly lower than that with retreatment (9.3% (29/312) vs 54.5% (54/99), χ ²=95.483, P<0.05); and the multidrug-resistance rate of patients with initial treatment was obviously lower than that with retreatment (2.9% (9/312) vs 33.3% (33/99), χ ²=75.944, P<0.05). The mutation rate of rifampicin and isoniazid at any site was 20.2% (83/411), among which, the mutation rate of rifampicin resistance gene (ropB) was 5.4% (22/411), including 20 cases with single-site mutations and 2 cases with double-site mutations, and the mutation frequency of 531 (C→T) was the highest (40.9% (9/22)); the mutation rate of isoniazid resistance genes (katG and inhA) was 4.6% (19/411), including 13 cases with katG mutation and 6 cases with inhA mutation, and the mutation frequency of 315 (G→C) was the highest (63.2% (12/19)); the multidrug-resistance rate was 10.2% (42/411), including 40 cases with double-site mutations, 1 case with three-site mutation and 1 case with four-site mutation, and the mutation frequency of 531 (C→T) 315 (G→C) was the highest (47.6% (20/42)). Conclusion The drug resistance of PTB patients in Longyan City is mainly multidrug-resistant. The resistance to two drugs in patients with retreatment is more serious than that in patients with initial treatment, indicates that the situation of prevention and treatment is grim.

Key words: Mycobacterium tuberculosis, Tuberculosis,multidrug-resistant, Isoniazid, Rifampin, Genes,bacterial, Point mutation, Small-area analysis