Antibiotic Resistance Trends and Prescribing Patterns in Pediatric Non-Typhoidal Salmonella Enteritis: A 10-Year Single-Centre Retrospective Study.

Abstract

Background: Non-typhoidal Salmonella (NTS) enteritis is a major cause of infectious diarrhoea in children and increasing antibiotic resistance is limiting treatment effectiveness. There is limited longitudinal data on resistance development and on how well prescribing practices align with resistance patterns in hospitalised children. This study aimed to assess trends in antibiotic resistance, the prevalence of multidrug resistance (MDR), and treatment concordance over a decade from a single Chinese Centre.

Methods: The study included children with microbiologically confirmed NTS enteritis with available antibiotic susceptibility data. Resistance rates for 11 antibiotics were calculated, and temporal trends were analysed using the Cochran-Armitage trend test. MDR was defined as resistance to three or more antibiotic classes. Treatment concordance was assessed by comparing the empiric antibiotic class with in vitro susceptibility results.

Results: Of 486 records reviewed, 422 children were included. Infants under one year included 69.4% of cases. S. Typhimurium was the predominant serotype (58.8%). Ampicillin resistance was highest at 76.3%, followed by ampicillin/sulbactam (61.8%) and co-trimoxazole (34.8%). Ceftriaxone resistance was 28.4%. Ampicillin/sulbactam resistance increased significantly over the decade (44.4% to 65.3%; p = 0.010), while ciprofloxacin resistance declined (44.4% to 4.0%; p = 0.005). MDR was identified in 23.0% of patients, without a significant temporal trend (p = 0.311). Most cases were classified as severe (75.4%), and piperacillin/tazobactam was the most commonly prescribed regimen (49.0%). Overall treatment concordance was 93.7%, with ceftriaxone exhibiting the highest discordance rate (14.9%).

Conclusion: Ampicillin/sulbactam resistance rose markedly, while ciprofloxacin resistance decreased in our cohort. The change may be related to reduced fluoroquinolone prescribing and broader antimicrobial-use policy shifts in our institute, although this cannot be confirmed without institutional prescribing data. One in four children showed MDR isolates. Discordance was highest for ceftriaxone-based regimens, indicating that empiric antibiotic selection should be guided by local institutional susceptibility surveillance rather than a fixed choice of agent. Ongoing monitoring of institutional resistance is vital to support antibiotic stewardship in pediatric NTS enteritis.