摘要
目的调查浙江儿童幽门螺杆菌(Hp)甲硝唑(MTZ)耐药状况及最低抑菌浓度(MIC)分布变化趋势;评估 E-test 法测定 MIC 的适用性;了解儿童体内 Hp 对 MTZ 体外耐药形成的倾向性。方法比较2002年10月至2003年11月44株与2004年12月至2005年7月83株 Hp 临床分离株的耐药率及 MIC 分布;E-test 法和琼脂稀释法同时测定55株 Hp 临床分离株对 MTZ 的 MIC;选用测定MIC 时空白对照培养基(不含 MTZ)上生长的甲硝唑敏感菌株(MTZ^S)共11株,行 MTZ 体外诱导。结果两组耐药率分别为31.8%和51.8%(x^2=4.64,P<0.05),MIC 值范围分别是<0.125～128mg/L 和0.25～>256 mg/L,MIC_(50)、MIC_(90)值分别为0.5 mg/L、128 mg/L 和16 mg/L、128 mg/L。对 Hp的 MTZ 耐药性与药敏感性判断,E-test 法对琼脂稀释法灵敏度73.08%,特异度100%,符合率87.27%,相关性好(x^2=32.38,P<0.001);两方法所有55株对应 MIC 值中28株有2~2～2~6个数量级以上差别。11株 MTZ^S 经7～9(7.2±0.6)代诱导达16倍 MIC;经8～10代诱导,诱导获得性耐药率100%,其中10株获得稳定的高度耐药(2株256 mg/L,8株>256 mg/L),1株获得64 mg/L 稳定的中度耐药。结论本地区儿童体内 Hp 对 MTZ 的耐药率呈升高趋势。因敏感性欠佳,E-test 法判断 Hp对 MTZ 敏感时需加做琼脂稀释法以降低耐药株漏诊率。儿童体内 Hp 对 MTZ体外诱导易于形成耐药。
Objective To investigate the prevalence of resistance of Helicobacter pylori （H. pylori） to metronidazole （MTZ） and the distribution change of minimal inhibitory concentrations （MICs） in H. pylori from local children, evaluate the applicability of E-test for MIC determination, and display the propensity of acquired-resistance to MTZ after induction of resistance in vitro. Methods One group of 44 H. pylori isolates obtained from Oct. 2002 to Nov. 2003 and another 83 H. pylori isolates obtained from Dec. 2004 to Jul. 2005 from the local children who underwent gastroscopy in the Children＇s Hospital affiliated to Zhejiang University Medical School and were diagnosed as H. pylori-associated gastritis or peptic ulcer were studied. Susceptibility was tested by agar dilution method or E-test method. In 11 randomly selected metronidazole-sensitive isolates （ MTZ^S ）, resistance was induced in vitro with MTZ. Results The resistance rate was 31.8% （14/44） in the 44-islates obtained from Oct. 2002 to Nov. 2003 and 51.8% （43/83） （χ^2 =4.64,P〈0.05） in 83-isolates obtained from Dec. 2004 to Jul. 2005, respectively. The distribution of MICs were 〈 0. 125-128 mg/L and 0. 25- 〉 256 mg/L, in which, the MIC50 was 0. 5 mg/L and 16 mg/L, the MIC90 was 128 mg/L, respectively. Comparing to agar dilution method which is recommended by National Committee for Clinical Laboratory Standards （NCCLS） for MIC, E-test was significantly associated with agar dilution method （ χ^2 = 32. 38, P 〈 0. 001 ）. The sensitivity, specificity, agreement rate of E-test were 73.08%, 100%, 87.27%, respectively, while there were factors of 2^2 to 2^6 difference in MICs between the results obtained by E-test and agar dilution. For all the 11 MTZ^S isolates inducted resistance in vitro with MTZ, 16 MICs were achieved through 7-9 （7.2±0.6） passages of induction in vitro, and 100% acquired-resistance to MTZ through 8-10 generations; as a result, 10 of 11 MTZ^S isolates achieved stable high-level resistance （256
出处
《中华儿科杂志》
CAS
CSCD
北大核心
2007年第10期765-768,共4页
Chinese Journal of Pediatrics
基金
浙江省卫生厅医药卫生重点项目基金(2003ZD009)
关键词
螺杆菌
幽门
微生物敏感性实验
甲硝唑
抗药性
细菌
儿童
Helicobacter pylori
Microbial sensitivity tests
Metronidazole
Drug resistance, bacterial
Child
