Clinical outcomes of continuous kidney replacement therapy in pediatric acute kidney injury: A systematic review

Abstract

Acute kidney injury (AKI) is common in critically ill children and is associated with morbidity and mortality. Continuous kidney replacement therapy (CKRT), historically termed continuous renal replacement therapy (CRRT), is used in severe AKI to manage fluid overload, metabolic disturbances, and hemodynamic instability. This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. PubMed, Europe PMC, Semantic Scholar, OpenAlex, and Google Scholar were searched for English- or Chinese-language studies published from January 2000 to August 10, 2026. Eligible studies included pediatric AKI treated with CKRT/CRRT or separately identifiable CKRT/CRRT subgroups. Two reviewers independently screened studies and extracted data. Observational studies were assessed using the Newcastle-Ottawa Scale, and the randomized crossover study was assessed using crossover Risk of Bias 2. Findings were synthesized narratively. Of 26 publications, 16 contributed primarily CKRT/CRRT-specific evidence and 10 provided contextual, complementary, or overlapping evidence. Mortality varied substantially across studies. Fluid overload was consistently associated with poorer outcomes. Renal recovery varied, with some survivors developing persistent kidney dysfunction, chronic kidney disease, or dialysis dependence. Urine output before or during CKRT discontinuation was associated with successful liberation. Comparative evidence was insufficient to determine whether any CKRT modality was superior. Overall certainty of evidence was low to very low. CKRT/CRRT is used as supportive therapy in critically ill children with severe AKI, particularly when complicated by fluid overload. Prospective multicenter studies are needed to clarify optimal timing, treatment strategies, and long-term kidney outcomes.