Surveillance of drug-resistance of Mycobacterium tuberculosis in Quzhou, Zhejiang

Objective To understand the drug resistance of clinical isolated Mycobacterium tuberculosis in Quzhou, Zhejiang province, and provide evidence for the prevention and treatment of tuberculosis.Methods The clinical strains isolated in 6 hospitals in Quzhou in 2010 were identified by differential medium culture method. The drug susceptibility of M. tuberculosis strains was detected with proportion method.Results Among 371 clinical isolated M. tuberculosis strains, 292(78.71%) were sensitive to four first line anti TB drugs(isoniazid, rifampicin, streptomycin and ethambutol), and 337(90.84%) were sensitive to two second line anti TB drugs(ofloxacin, and kanamycin). Among 89 drug resistant strains, 51(13.75%) were single drug resistant, 14(3.77%) were poly-resistant, 21(5.66%) were multidrug resistant and 3(0.81%) were extensive drug resistant. The resistant rate to isoniazid, rifampicin, streptomycin, ethambutol, ofloxacin and kanamycin was 15.36%, 7.01%, 11.86%, 3.23%, 7.82% and 2.42% respectively. Among 326 patients receiving initial treatment, the resistant rate to isoniazid, rifampicin, streptomycin, ethambutol, ofloxacin and kanamycina was 10.12%, 2.45%, 8.90%, 1.23%, 3.68% and 1.53% respectively, The non drug resistant and MDR rates were 80.98% and 1.84%. Among 45 patients receiving re-treatment, the resistant rate to isoniazid, rifampicin, streptomycin, ethambutol, ofloxacin and kanamycin was 53.33%, 40.00%, 33.33%, 17.78%, 37.78% and 8.89% respectively, and the non drug resistant and MDR rates were 40.00% and 33.33%.Conclusion The drug resistance of the clinical isolated M. tuberculosis strains in Quzhou was very serious, and the drug resistant rate was higher in the patients receiving retreatment than in the patients receiving initial treatment, to which close attention should be paid. It is necessary to enhance the implementation of DOTS strategy.