Prevalence, risk factors and outcomes of sepsis-associated acute kidney injury in pediatric patients

Sepsis-associated acute kidney injury (SA-AKI) is a common and serious complication in critically ill children and is associated with increased mortality and healthcare utilization. Early identification of high-risk patients may improve outcomes. This study aimed to determine the prevalence, risk factors, and clinical outcomes of SA-AKI in pediatric patients with sepsis and to identify independent predictors of severe disease. A single-center retrospective cohort study was conducted at Ramathibodi Hospital between January 2018 and April 2022. Children aged > 1 month to < 20 years diagnosed with sepsis were included. AKI was defined according to the KDIGO criteria, and AKI occurring in patients with sepsis was classified as SA-AKI. Patients were categorized into sepsis without acute kidney injury (non-AKI) and sepsis-associated acute kidney injury (SA-AKI) groups. Multivariable logistic regression was performed to determine independent predictors of severe SA-AKI (stage 3), reported as adjusted odds ratios (AOR) with 95% confidence intervals (CI). Among 201 children with sepsis, 81 (40.3%) developed SA-AKI, including 26 (12.9%) with stage 3 disease. Patients with SA-AKI had significantly higher 30-day mortality (33.3% vs. 5.8%, p < 0.001), higher in-hospital mortality (35.8% vs. 7.5%, p < 0.001), longer PICU length of stay (median 3 vs. 1 day, p < 0.001), and greater need for continuous renal replacement therapy (7.4% vs. 0.8%, p = 0.018). Severe SA-AKI was independently associated with percentage fluid overload within 72 h (AOR 1.10, 95% CI 1.01–1.20, p = 0.031) and renal angina index (RAI) score ≥ 8 (AOR 22.39, 95% CI 3.04-164.86, p = 0.002). In this middle-income Southeast Asian tertiary PICU cohort, SA-AKI affected nearly half of pediatric sepsis patients and was strongly associated with increased mortality and critical care resource utilization. Higher fluid overload and RAI score ≥ 8 were independent predictors of severe SA-AKI. Early assessment of fluid balance and renal angina index may improve risk stratification and facilitate timely intervention to prevent progression to severe kidney injury.