Drug resistance characteristics and risk factors in patients with retreated pulmonary tuberculosis: a 5-year retrospective study in Suzhou, China

Objective We conducted a systematic evaluation of TB-infected patient data from January 2020 to December 2024 to statistically analyze retreatment risk factors and drug resistance profiles among culture-positive TB patients in Suzhou. Methods This investigation assessed the incidence of TB retreatment and drug resistance patterns in Suzhou, Jiangsu Province, China. Patients were stratified by diagnosis year, sex, age, and disease status. Using individual case records of pulmonary TB patients, drug resistance screening results, and clinical data of drug-resistant patients (01/01/2020-31/12/2024), we employed the chi-square test for group comparisons and multivariate logistic regression to identify influencing factors. Results From 2020-2024, a total of 10,898 TB patients were enrolled, including 6,820 Mycobacterium tuberculosis culture-positive patients. Among these culture-positive cases, 167 patients required retreatment, yielding an annual incidence of 228 retreatment cases per 10,000 person-years. The incidence of extensively drug-resistant TB (XDR-TB) is 528 per 10,000 person-years. Multivariate logistic regression analysis revealed that anemia, XDR-TB, bronchiectasis, and fatty liver were significantly associated with an increased risk of TB retreatment. Conclusion Bronchiectasis, anemia, fatty liver, hepatitis B, and extensively drug-resistant Mycobacterium tuberculosis increase the risk of tuberculosis retreatment. Comorbid bronchiectasis is specifically associated with an increased risk of rifampicin resistance, streptomycin resistance, and XDR-TB.