Bacterial profile and antimicrobial resistance patterns among pediatric intensive care unit patients in Ethiopia: a retrospective cohort study, 2020–2025

Abstract Background Antimicrobial resistance (AMR) poses a growing threat in pediatric intensive care units (PICUs), where critically ill children face heightened exposure to invasive procedures and broad-spectrum antibiotics. Despite increasing reports of multidrug-resistant (MDR) pathogens across Ethiopia, data on the bacterial epidemiology of infections and clinically significant resistance patterns among non-neonatal PICU patients remain limited. This study aimed to describe the distribution of bacterial isolates and antimicrobial resistance patterns among pediatric patients admitted to the PICU at Asella Teaching and Referral Hospital (ATRH), Ethiopia, and to perform an exploratory secondary analysis of factors associated with high-risk AMR. Methods A hospital-based retrospective cohort study was conducted using five years of medical and microbiological records (July 2020 – June 2025). Pediatric patients aged 29 days to 14 years with available culture results were included. High-risk AMR was defined as the presence of any of the following phenotypes per WHO classification: multidrug-resistant (MDR), extensively drug-resistant (XDR), pan-drug-resistant (PDR), ESBL-producing organisms, and carbapenem-resistant Enterobacterales (CRE). These categories are not mutually exclusive; an isolate may fulfill more than one criterion simultaneously. Descriptive statistics summarized pathogen distribution and susceptibility patterns. An exploratory binary logistic regression (a = 0.05) was performed as a secondary analysis. Results Among 217 PICU patients reviewed, the crude culture yield was 52.5% ( n = 114); bacteriologically significant cultures, excluding coagulase-negative staphylococci (CoNS) classified as likely contaminants, were identified in 31.3% ( n = 68). Among 112 bacterial isolates, Gram-negative organisms accounted for 54.5% ( n = 61 of 112 isolates across all culture types); Klebsiella species were the most frequent Gram-negative pathogen. AST was performed for 66 clinically significant isolates, one per patient. Among these, 45 (68.2%) demonstrated high-risk AMR phenotypes, including ESBL-producing organisms (19.7%), XDR (15.2%), MDR (13.6%), PDR (13.6%), and CRE (6.1%). Resistance was near-universal for ampicillin (91.3%) and ceftazidime (92.3%); amikacin (83.3% susceptible) and meropenem (85.7% susceptible) retained favorable profiles. In the exploratory regression, prolonged PICU stay (per additional day) was associated with high-risk AMR (AOR 7.59, 95% CI: 1.10–52.60; p = 0.040); however, this estimate is statistically unstable and should not be interpreted as a valid per-day effect. Conclusion This study documents a substantial burden of high-risk AMR (68.2%) and near-universal resistance to beta-lactam antibiotics among PICU patients at ATRH, Ethiopia. The antibiogram data — including preserved susceptibility to amikacin and meropenem — may inform institutional stewardship program development. Prospective multicenter surveillance with standardized microbiological protocols is urgently needed.