腹泻儿童非伤寒沙门菌感染的病原学及耐药性分析

Etiology and drug resistance of non-typhoid Salmonella infection in children with diarrhea

目的探究苏州地区腹泻儿童非伤寒沙门菌(NTS)感染的病原学特征及耐药性变迁。方法回顾性收集2016年至2021年苏州大学附属儿童医院收治的1265例NTS感染相关腹泻患儿的临床数据并进行统计分析。结果本研究共分离得到1265株NTS,平均检出率为11.79%,主要以5岁以下低龄儿童为主,夏季为高发流行季节(20.00%),优势血清群为B群(63.95%)和D群(17.00%),其中以鼠伤寒沙门菌(54.47%)和肠炎沙门菌(15.18%)为主;药敏结果显示,苏州地区腹泻患儿分离得到的NTS对广谱合成类青霉素敏感性较低(耐药率均>70%),而对含酶抑制剂的青霉素复合制剂较为敏感(耐药率均<10%),对三代头孢菌素及其复合制剂、碳青霉烯类抗生素敏感性也较好;不同血清型沙门菌的耐药性也存在差异,D群沙门菌环丙沙星和复方新诺明总体耐药率均低于其他血清群(χ^(2)值分别为20.71、147.24,P<0.05);2020—2021年分离的NTS对三代头孢菌素和氟喹诺酮类药物的耐药率较往年明显下降(χ^(2)值分别为29.02、11.55,P<0.05)。结论NTS是导致苏州地区儿童感染性腹泻的主要病原菌,临床医生应认识到NTS的病原学特征及耐药性改变,帮助早期诊断和合理使用抗菌药物,延缓耐药菌株的产生。

Objective To explore the etiological characteristics and drug resistance of non-typhoid Salmonella(NTS)infection in children with diarrhea in Suzhou.Methods The clinical data of 1265 children with NTS infection and diarrhea who admitted to the Children's Hospital of Soochow University from 2016 to 2021 were retrospectively collected and statistically analyzed.Results A total of 1265 strains of NTS were obtained,with an average detection rate of 11.79%,mainly in children under 5 years old.Summer was the high prevalence season(20.00%),and the dominant serogroups were Group B(63.95%)and Group D(17.00%).Among them,Salmonella typhimurium(54.47%)and Salmonella enteritis(15.18%)were dominant.The results of antimicrobial susceptibility testing showed that NTS isolated from children with diarrhea in Suzhou had low sensitivity to broad-spectrum synthetic penicillin(resistance rate>70%),but were sensitive to penicillin compound preparations containing enzyme inhibitors(resistance rate<10%),and sensitive to three generation cephalosporins and their compound preparations,carbapenems antibiotics.In addition,the antimicrobial susceptibility to the third-generation cephalosporins and their combinations and carbapenems were also performed well.There were differences in drug resistance among different serotypes of Salmonella.Overall drug resistance rates of ciprofloxacin and cotrimoxazole in D group Salmonella were lower than other serogroups(χ^(2)=20.71 and 147.24,respectively,P<0.05).Compared with previous years,the drug resistance rate of third-generation cephalosporins and fluoroquinolones in NTS isolated from 2020-2021 decreased significantly(χ^(2)=29.02 and 11.55,respectively,P<0.05).Conclusion NTS is the main pathogen of infectious diarrhea in children from Suzhou area.Clinicians should recognize the etiological characteristics and drug resistance changes of NTS,which help early diagnosis and appropriate using of antibiotics,and delay the generation of drug-resistant strains.