Age-Stratified Clinical and Microbiological Profiles in Pediatric Infectious Disease Admissions: Implications for Risk Prediction and Antimicrobial Stewardship

<b>Background/Objectives</b>: Pediatric infectious-disease admissions are common but heterogeneous. We characterized clinical, microbiological, and therapeutic patterns and identified high-risk subgroups relevant to antimicrobial stewardship. <b>Methods</b>: In an observational cohort of 136 children stratified by age, we recorded symptoms, diagnoses, culture results, pathogens, antibiotic therapy, and outcomes. A composite risk score integrating age and clinical/microbiological parameters was assessed. <b>Results</b>: Outcomes were generally favorable: intensive care unit (ICU) transfer 8.8% (95% confidence interval [CI]: 4.6-15.1), mortality 0.7% (95% CI: 0.1-3.9), and median length of stay (LOS) 10 days (interquartile range [IQR] 8-12). Pneumonia was the leading diagnosis (44.9%; 95% CI: 36.3-53.6). Among isolates, <i>Escherichia coli</i> (47.1%) and <i>Klebsiella</i> species (spp.) (27.9%) predominated. Pneumonia correlated with prolonged LOS (<i>p</i> = 0.006), and gastroenteritis with ICU transfer (<i>p</i> = 0.038) and longer LOS (<i>p</i> = 0.018). Mixed <i>E. coli</i> + <i>Klebsiella</i> infections were linked to prolonged stay (<i>p</i> = 0.021). The composite score identified a high-risk stratum with higher ICU transfer (<i>p</i> = 0.004) and prolonged stay (<i>p</i> = 0.006). <b>Conclusions</b>: Although overall outcomes were favorable, risk was not uniform. An age-stratified, multifactorial assessment-integrating clinical presentation, microbiology, and a composite score-identified pediatric subgroups with worse prognoses, supporting targeted monitoring and stewardship-aligned, age-aware empiric therapy. External validation is warranted.