Retrospective study links pediatric invasive Salmonella cases to summer clustering and uneven cephalosporin resistance

A single-center retrospective study of 67 children hospitalized with invasive nontyphoidal Salmonella infection found that cases were concentrated among very young children and clustered seasonally. The cohort had a median age of 15 months, with an interquartile range of 10.5 to 27 months, and 70.1% of patients were between six months and two years old. According to the published abstract, 59.7% of cases had disease onset between July and September.

Investigators retrospectively reviewed clinical records for children hospitalized at the institution from 2022 through 2025. Invasive nontyphoidal Salmonella infection was defined as isolation of nontyphoidal Salmonella from blood, bone marrow, synovial fluid or another normally sterile-site specimen. The analysis collected demographic characteristics, clinical manifestations, laboratory findings, serovar identities and antimicrobial susceptibility results. Fever occurred in every patient, and more than half also had gastrointestinal symptoms. Severe focal complications, including osteomyelitis and arthritis, occurred in only a small proportion of cases. The authors described these clinical manifestations as nonspecific, which the abstract says can make early recognition challenging.

Twenty-six serovars were identified. Enteritidis, Muenster and Typhimurium were the predominant serovars, although each represented a small group: eight Enteritidis isolates, eight Muenster isolates and seven Typhimurium isolates. Third-generation cephalosporin resistance occurred in six of eight Muenster isolates and two of seven Typhimurium isolates, while none of the eight Enteritidis isolates showed this resistance. Across the full cohort, reported resistance rates to third-generation cephalosporins ranged from 25.4% to 29.9%. Most isolates remained susceptible to beta-lactam/beta-lactamase inhibitor combinations, carbapenems and tigecycline, whereas susceptibility to levofloxacin was low.

These findings are based on the published abstract of a retrospective cohort from one center and do not establish changes in resistance over time, causal relationships or population-wide rates. The abstract did not report the institution’s location, detailed laboratory findings, outcome data, methods for addressing missing observations or measures of potential selection bias. It also does not provide enough information to determine whether the observed seasonal pattern or serovar-specific resistance reflects wider epidemiology. The report therefore characterizes variation within this hospitalized pediatric cohort without establishing how broadly the patterns apply.

Subject of Research: Clinical features, serovar distribution and antimicrobial susceptibility in children hospitalized with invasive nontyphoidal Salmonella

Article Title: Clinical features and antimicrobial resistance of invasive nontyphoidal Salmonella infections in children: a single-center retrospective study

Article References: Peng, Q., & Lin, Y. (2026). Clinical features and antimicrobial resistance of invasive nontyphoidal Salmonella infections in children: a single-center retrospective study. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14490-1

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DOI: 10.1186/s12879-026-14490-1

Keywords: pediatric invasive Salmonella, nontyphoidal Salmonella, antimicrobial resistance, third-generation cephalosporins, serovar distribution, seasonal onset, retrospective cohort, children, Clinical, features, antimicrobial, resistance