Antimicrobial Consumption and Prescribing Patterns in Hospitalized Children During and After the COVID-19 Pandemic.

The COVID-19 pandemic shifted pediatric infection epidemiology from bacterial toward viral predominance as public health measures relaxed. To determine how hospital antibiotic prescribing adapted, antimicrobial consumption was characterized and linked to underlying pathogen type. Antibiotic use was retrospectively analyzed among 567 children admitted with a positive microbiological finding to the pediatric ward of a tertiary hospital in Split, Croatia, during the first quarters of 2021-2024. Consumption was quantified using Days of Therapy (DOT), Length of Therapy (LOT), and Days of Antibiotic Spectrum Coverage (DASC) per 1000 patient-days (PD). Antibiotics were grouped by the WHO Access/Watch/Reserve (AWaRe) classification and linked to discharge diagnosis and pathogen type. The proportion of children receiving antibiotics rose from 60.5% (26/43) in 2021 to 71.4% (130/182) in 2024, with the cohort shifting toward younger infants and virally driven diagnoses. DOT, DASC, and DOT/LOT peaked in 2022 (DOT 2164/1000 PD, DOT/LOT 2.2) before settling near 1400/1000 PD, with mean per-day spectrum (DASC/DOT) declining modestly (7.7 to 6.8). Watch-group antibiotics dominated throughout (~80%), with Access contribution of ~20% and Reserve antibiotic use negligible. Ceftriaxone usage rose fivefold (150 to 755 DOT/1000 PD) to become the leading agent. Ceftriaxone and azithromycin were administered more often to children with viral than bacterial infections (respiratory syncytial virus being most common), whereas vancomycin and meropenem were tied to bacterial isolates. These findings identify a high-yield stewardship target and underscore the value of multi-metric, pathogen-aware surveillance.