为了解复旦大学附属金山医院近年来明显增多的非伤寒沙门菌(nontyphoidal Salmonella，NTS)感染儿童病例的临床特点及病原体特征，本研究回顾性分析了2018年1月—2021年12月该院NTS感染患儿的临床特征、血清型分布及耐药情况，并比较新型冠状病毒感染(简称新冠)疫情出现前后的差异。2018—2021年该院腹泻患儿中NTS的平均分离率为18.1%(110/609)，其中2020—2021年(新冠疫情开始后)的分离率(21.3%，57/268)明显高于2018—2019年(15.5%，53/341)(P＝0.04)。NTS感染病例主要集中在6 个月～< 3 岁年龄段(80.0%，88/110)，多发于每年的5—10月(84.5%，93/110)。临床症状常见发热(70.9%)和肉眼血便(22.7%)；均接受第3代头孢菌素类抗生素治疗，疗程一般为5～7 d，所有患儿均临床痊愈。共检出21种血清型，其中鼠伤寒沙门菌单相变种最常见(29.1%，32/110)，其次是鼠伤寒沙门菌(26.4%，29/110)。药敏试验结果显示，NTS对头孢曲松的耐药率为21.8%，对阿奇霉素和环丙沙星的耐药率较低(分别为8.2%和6.4%)；29.1%的菌株为多重耐药株，2.7%的菌株对所检测抗菌药物均耐药。NTS已成为上海金山及其周边地区儿童急性肠炎的重要病原体，且感染率呈上升趋势，很可能与鼠伤寒沙门菌及其单相变种感染增多有关，对目前临床常用的第3代头孢菌素类抗生素的耐药率较高，因此有必要持续监测NTS的流行特征及其对抗菌药物耐药性的变化。

To explore the clinical features and pathogenic characterization of the obviously increasing paediatric cases caused by nontyphoidal Salmonella (NTS) in recent years, the present study retrospectively analyzed the clinical features, distribution of serovars, and antimicrobial resistance of NTS in the infected children in Jinshan Hospital of Fudan University between January 2018 and December 2021. The difference in these features between before and after the Corona Virus Disease 2019 (COVID-19) epidemic was also analyzed. The average isolation rate of NTS in paediatric diarrhea cases was 18.1% (110/609), with the rate significantly higher in 2020-2021 (after the beginning of COVID-19) (21.3%，57/268) than in 2018-2019 (15.5%, 53/341, P＝ 0.04). NTS-infected cases were more frequent in the age group of 6 months to 3 years old (80.0%, 88/110), peaking from May to October (84.5%, 93/110). The common clinical symptoms included fever (70.9%) and blood-in-stool (22.7%). The children with NTS infections were administrated with the third-generation cephalosporins, and the therapy mostly lasted for five to seven days. All the cases recovered. The NTS isolates represented 21 serovars, with monophasic variant of S. Typhimurium the commonest (29.1%, 32/110), followed by S. Typhimurium (26.4%, 29/110). Antimicrobial susceptibility testing showed that the resistance rate of NTS isolates to ceftriaxone was 21.8%, while the resistance rates to azithromycin and ciprofloxacin were both very low (8.2% and 6.4%, respectively). 29.1% of the NTS isolates were multidrug-resistant, while 2.7% were resistant to all the tested antibiotics. NTS has become an important pathogen responsible for bacterial inflammatory diarrhea in the children residing in and around Jinshan District of Shanghai. The prevalence of NTS infections is increasing, which is probably associated with the increase of infections caused by S. Typhimurium and its monophasic variant. These NTS isolates show a high resistance rate to the third-generation cephalosporins which are often used in the clinical practice. Therefore, it is necessary to warrant continual surveillance on the changes of epidemiological features and antimicrobial resistance of NTS.