Major adverse kidney events (MAKE), a composite of death, dialysis dependence, and persistent kidney dysfunction, are important outcomes in critically ill children receiving continuous renal replacement therapy (CRRT). However, multicenter data on MAKE after pediatric CRRT remain limited. We aimed to determine the incidence of MAKE 6 months after pediatric intensive care unit (PICU) discharge and identify associated factors.

We conducted a multicenter observational study using data from the Japanese Pediatric CRRT Registry (jpCRRT registry). Patients aged <16 years who underwent CRRT for acute illness in participating PICUs between January 2023 and May 2026 were included. Patients receiving chronic maintenance dialysis were excluded. The primary outcome was MAKE 6 months after PICU discharge, defined as death, dialysis dependence, or persistent kidney dysfunction. Candidate variables included patient characteristics, illness severity, pre-CRRT support, CRRT indications, urine output, laboratory data before CRRT, time to CRRT initiation, and initial CRRT factors. Variables were selected using LASSO regression, with clinically important variables based on previous studies forced into the model. Selected variables were then evaluated using multivariable logistic regression.

A total of 129 patients were analyzed. The median age was 13 months (IQR, 0–68); 82 patients (63.6%) were male, and 41 (31.8%) had congenital heart disease. The median pediatric Sequential Organ Failure Assessment score was 9 (IQR, 5–12). Extracorporeal membrane oxygenation was used in 50 patients (38.8%), and mechanical ventilation in 113 (87.6%). MAKE occurred in 54 patients (41.9%), including death in 35 (27.1%), dialysis dependence in 5 (3.9%), and persistent kidney dysfunction in 14 (10.9%). In the multivariable model, higher pre-CRRT vasoactive-inotropic score was associated with MAKE (OR, 1.05 per 1-point increase; 95% CI, 1.01–1.09), whereas higher urine output during the 24 hours before CRRT was associated with lower odds of MAKE (OR, 0.91 per 10 mL/kg/day increase; 95% CI, 0.84–0.99).

In the jpCRRT registry, MAKE 6 months after PICU discharge occurred in approximately 40% of children receiving CRRT. Pre-CRRT urine output and vasoactive-inotropic support were associated with MAKE. These readily available factors may identify children who require kidney-focused follow-up after PICU discharge.