广州地区急性腹泻患儿粪便中多重耐药及高毒力肺炎克雷伯菌分布检测

目的 了解广州地区急性腹泻患儿粪便中肺炎克雷伯菌的携带情况，以及其中具有多重耐药性和高毒力的肺炎克雷伯菌菌株的分布情况。方法 2015年5~9月，采集广州市某医院门诊腹泻患儿的粪便样本，分离鉴定肺炎克雷伯菌并进行药敏试验，同时筛检产超广谱β-内酰胺酶（extended-spectrum β-lactamases，ESBLs）菌株。采用聚合酶链式反应（polymerase chain reaction，PCR）实验检测产ESBLs菌株中具有耐药基因bla_TEM、bla_SHV和bla_CTX-M的菌株分布情况；用PCR实验检测所有分离菌株中六种常见高毒力荚膜血清型的分布情况。结果 在87份腹泻患儿粪便样本中，肺炎克雷伯菌检出率为66.7%。分离株对青霉素类抗菌药物、第一代头孢菌素和呋喃妥因的耐药率较高；而对二、三、四代头孢类抗菌素、喹诺酮类、氨基糖苷类抗生素耐药性较低，且未检出耐碳青霉烯肺炎克雷伯菌；产ESBLs肺炎克雷伯菌检出率为12.1%（7/58），其中检出4株bla_CTX-M和2株bla_TEM基因型菌株，未检出含bla_SHV基因型菌株；所有分离株的多重耐药率为27.6%。共检出高毒力肺炎克雷伯菌K2、K20、K54型各1株，未检出K1、K5及K57型。结论 腹泻患儿粪便中肺炎克雷伯菌分离率较高，多重耐药性菌株比例较高，而且存在具有多重耐药同时高毒力的菌株，应引起重视。

The prevalence,multidrug resistance and hypervirulence of klebsiella pneumoniae in feces from children with a cute diarrhea in Guangzhou

Objective The aim of this study was to understand the prevalence,multidrug resistance and hypervirulence of Klebsiella pneumoniae (KP) in feces from children with acute diarrhea in Guangzhou City.Methods Fresh fecal samples from children with acute diarrhea were collected between May and September in 2015.Colonies of KP were isolated and identified.Antimicrobial susceptibility of KP isolates was conducted.Screening and phenotypic confirmatory tests for extended-spectrum β-lactamases(ESBLs) in KP were conducted for ESBLs-producing isolates.To investigate the prevalence of ESBL type of KP,three resistance genes including blaTEM,blaSHV and blaCTX-M among ESBLs-producing isolates were detected by using polymerase chain reaction (PCR).Six common capsular serotypes of hypervirulent KP (hvKP) among all KP isolates were screened by using PCR.Results A total of 87 fecal specimens were collected from out-patient children with acute diarrhea.The prevalence of KP was 66.7％.There were high resistance rates of KP isolates to penicillins,first-generation cephalosporins and nitrofurantoin,while the resistance rates to quinolones,aminoglycosides,second-,third-,and fourth-generation cephalosporins were lower.Carbapenem resistant KP was not detected in this study.The prevalence of ESBLs-producing isolates was 12.1％ (7/58).Among all ESBLs-producing isolates,4 isolates were TEM and 2 isolates were CTX-M types.However,no SHV type isolates were identified.The proportion of multidrug resistance was 27.6％ (16/58).In addition,three hvKP isolates were detected,of which the capsular serotypes were proved to be K2,K20 and K54,respectively.The type of K1,K5 and K57 isolates were not detected.Conclusions There was high prevalence rate of KP isolated from children with acute diarrhea.The serious multidrug resistance of KP and the hvKP with multidrug resistance should be taken into consideration.