Drug resistance of pulmonary tuberculosis cases in Ningbo, Zhejiang, 2017

ObjectiveTo evaluate the levels and patterns of drug resistance in initially treated smear-negative pulmonary tuberculosis (TB) patients in Ningbo, and provide scientific evidence for the prevention and control of drug-resistant TB.

MethodsSputum samples of 1 434 initially treated smear-negative pulmonary TB patients enrolled from March to December 2017 were isolated by liquid culture method. Strain identification and drug susceptibility tests were performed for all culture positive samples with proportion method.

ResultsA total of 378 sputum samples from the 1 434 enrolled pulmonary TB patients were culture positive, in which 60 were non-tuberculosis mycobacterium positive. Eight six of 318 pulmonary TB cases were drug-resistant, the overall drug-resistance rate was 27.04%, with the highest resistance rate to isoniazid (17.92%, 57/86), and the lowest drug-resistance rate to rifampicin (5.35%, 17/86). The resistance rate to rifampicin in pulmonary TB patients with cavitation was significantly higher than that in those without cavitation (χ²＝5.319, P＜0.05).

ConclusionThe drug resistance in initially treated smear-negative pulmonary TB cases was relatively severe in Ningbo. Further efforts should be made to expand drug susceptibility test coverage to find drug-resistant patients timely and improve the treatment and management of pulmonary TB cases.