云南省玉溪市甲型副伤寒沙门菌对抗生素的敏感性分析

目的 了解云南省玉溪市甲型副伤寒沙门菌(Salmonella paratyphi A, SPA)对抗生素的敏感性及耐药趋势,为临床医生合理用药、有效治疗患者、清除传染源提供依据。 方法 采用纸片K-B法扩散技术检测玉溪市2005-2011年分离的252株SPA对17种抗生素的敏感性;并采用 Etest测试条进行喹诺酮类(萘啶酸、环丙沙星、左氧氟沙星、诺氟沙星)抗生素最低抑菌浓度(minimum inhibitory concentration,MIC)测定。 结果 分离株对氨苄西林、阿莫西林、头孢噻吩、亚胺培南、奈替米星、复方新诺明、氯霉素7种抗生素均敏感;头孢噻肟的敏感率为99.21%;四环素、氨曲南、左氧氟沙星的敏感率为98.41%;呋喃妥因、诺氟沙星、环丙沙星的敏感率分别为97.62%、95.63%和36.51%;洛美沙星、萘啶酸的敏感率仅为0.79%,所有分离株对利福平耐药;分离株对洛美沙星的中介率逐年下降,耐药率逐年上升;对环丙沙星的中介率不断上升,敏感性不断降低。250株分离株属于萘啶酸抗性(nalidixic acid-resistant,NAR)株,其余2株属于萘啶酸敏感(nalidixic acid-sensitive, NAS)株, NAR株降低了对氟喹诺酮类药物的敏感性,NAR分离株MIC值远远高于NAS株的MIC(χ2=244.063, P结论 第三代头孢菌素可作为玉溪境内治疗甲型副伤寒的首选药物;当地SPA对氟喹诺酮类抗生素耐药性呈上升趋势,合理应用该类药物,对遏制耐药性的进一步发展,具有十分重要的意义。

Drug susceptibility of Salmonella paratyphi A in Yuxi, Yunnan

Objective To investigate the drug susceptibility trend of Salmonella paratyphi A (SPA) in Yuxi, Yunnan province, and provide evidence for the clinical use of antibiotics, patient treatment and eliminating infection source. Methods The K-B disk diffusion method was used to detect the drug susceptibility of 252 SPA isolates collected from 2005 to 2011 to 17 antibiotics. Furthermore, Etest test strip was used to test the minimum inhibitory concentration (MIC) of quinolones, including nalidixic acid, ciprofloxacin, levofloxacin and norfloxacin. Results The isolates were sensitive to ampicillin, amoxicillin, cephalothin, imipenem, netilmicin, sulfamethoxazole/trimethoprim and chloromycetin. The sensitive rate was 99.21% to cefotaxime, 98.41% to tetracycline, aztreonam and levofloxacin, 97.62% to nitrofurantoin, 95.63% to norfloxacin and 36.51% to ciprofloxacin. However, the sensitive rates to lomefloxacin and nalidixic acid were only 0.79%. All SPA isolates were resistant to rifampicin. The isolates’ intermediate rate to lomefloxacin declined with year, whereas the resistance rate increased with year. Moreover, the isolates’ intermediate rate to ciprofloxacin increased, but the sensitive rate decreased with year. Among 252 SPA isolates, 250 isolates were nalidixic acid resistant (NAR), the other 2 isolates were nalidixic acid sensitive (NAS). NAS isolates are more sensitive to the fluoroquinolones than NAR isolates, because the MICs of NAR isolates are much higher than those of NAS isolates (χ2=244.063,PConclusion Third generation cephalosporins could be used as the first choice in the treatment of Paratyphoid fever in Yuxi. The resistance of local SPA stains to fluoroquinolones is in increase, so the rational use of this antibiotic is important to stop the spread of their drug resistance.