Description of occurrence, serotyping, and antimicrobial resistance of Salmonella in children aged 0-15 years at the Hospital del Niño Dr. José Renán Esquivel, Panama. 2019-2025.

Abstract

Introduction: Salmonellosis is an infectious disease caused by bacteria of the genus Salmonella, with over 2,600 recognized serotypes worldwide. The World Health Organization (WHO) considers it a high-priority pathogen, responsible for approximately 3.4 million cases of invasive non-typhoidal Salmonella (NTS) infection annually, with particular impact on pediatric populations of middle- and low-income countries. In Panama, data on circulating serotypes and antimicrobial resistance in children are scarce.

Objective: To describe the occurrence, serotyping, and antimicrobial resistance of Salmonella in children aged 0-15 years treated at the HNJRE during the period 2019-2025.

Methods: Descriptive, retrospective, and cross-sectional study. Clinical and laboratory records from HNJRE were reviewed. The study universe comprised 92 cases; the final sample included 88 cases. Data were collected from September to December 2025. Sociodemographic variables, clinical diagnosis, biological sample type, serotypes, and antimicrobial resistance profiles were analyzed.

Results: 88.6% of cases were in the 0-4 year age group. Male sex predominated (54.6%). The provinces with the highest occurrence were Panama (51%, n=45) and Panama Oeste (22%, n=19). The most frequent clinical diagnosis was gastroenteritis (46%). The predominant symptoms were fever (51%) and diarrhea (43%). 46% of isolates came from stool samples and 39% from peripheral blood. Salmonella Infantis was the most frequent serotype (14%), followed by Salmonella Enteritidis (10%) and Salmonella Typhimurium (8%). A growing trend in ceftriaxone resistance was observed, reaching 38-39% in 2024-2025. Non-susceptibility to ciprofloxacin increased progressively from 0% (2019) to 44% (2025), predominantly in the intermediate category. Trimethoprim-sulfamethoxazole (TMP-SMX) maintained high susceptibility (≥94%) throughout the period. Carbapenems retained full efficacy.

Conclusions: Children under 4 years of age represent the most vulnerable group. Increasing ceftriaxone resistance and declining ciprofloxacin susceptibility are the most clinically and epidemiologically relevant findings. TMP-SMX remained an effective therapeutic option. Carbapenems preserved their activity throughout the study period.