Continuous Renal Replacement Therapy for Acute Decompensation in Inborn Errors of Metabolism: Single-Center, Pediatric Cohort, 2014–2025

OBJECTIVES: To review our use and outcomes of continuous renal replacement therapy (CRRT) for acute metabolic decompensation (hyperammonemia or hyperleucinemia) in infants and children with inborn errors of metabolism (i.e., M), and to identify factors associated with complications and mortality. DESIGN: Retrospective cohort identified using local clinical databases. SETTING: Single-center PICU and neonatal ICU in a tertiary pediatric center in Türkiye. PATIENTS: Thirty-eight children (with 49 CRRT sessions) for urea cycle disorders, organic acidemias, or maple syrup urine disease undergoing treatment between August 2014 and June 2025. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The median (interquartile range, IQR) age at CRRT initiation was 1.4 months (IQR 0.16-33.90); CRRT resulted in substantial metabolite reduction (mean change 87.6% for ammonia and 74.8% for leucine). Younger age was associated with more hemodynamic and metabolic complications. Overall mortality was 11 of 38 (28.9% [95% CI, 17-44.8%]). In the 11 episodes of CRRT that ended in death vs. 38 CRRT episodes with survival to discharge, there was a greater proportion with hypophosphatemia: 6 of 11 vs. 8 of 38, percentage difference 33.4% (95% CI, 2.8-59.6%), p value of equals to 0.03. Last, we failed to identify an association between episodes of CRRT by technique (continuous venovenous hemodiafiltration [CVVHDF] vs. dialysis) and mortality: 6 of 21 vs. 5 of 28, mean difference 10.7% (95% CI, -12.4 to 34.3%), p value of equal to 0.38. CONCLUSIONS: In our single-center 11-year experience of using CRRT for metabolic detoxification in critically ill young infants with inborn errors of metabolism, we have found that substantial reductions in ammonia and leucine can be achieved in severe biochemical derangement, irrespective of whether continuous venovenous hemodialysis or CVVHDF was used. Taken together, for us, these findings reinforce our continued practice of timely CRRT as a critical component of acute metabolic crisis management.