Protein catabolism in pediatric patients on chronic peritoneal dialysis

Abstract

Energy deficiency and protein catabolism affect the growth of children with chronic kidney disease (CKD). Current protein recommendations are based on the Dietary Reference Intakes (DRI 2005) and nitrogen balance studies in children undergoing chronic peritoneal dialysis (CPD), including nitrogen losses in dialysate fluid, urine, and feces.

Objective: To estimate protein requirements in children on CPD by measuring total protein catabolism (tPC) plus growth requirements and comparing them with international recommendations, and analyze the clinical intervention based on individualized protein adjustments according to tPC values to achieve a growth nitrogen balance.

Patients and Method: Retrospective and analytical study. We reviewed clinical records of pediatric patients on CPD, treated at a referral hospital in Santiago, Chile, between 2017 and 2024. tPC values plus growth requirements were compared with the Kidney Disease Outcomes Quality Initiative (KDOQI) 2009 guidelines. Key biochemical parameters as treatment targets in this condition and length- or height-for-age Z-score were assessed at baseline and after 12 months of follow-up, adjusted for protein intake.

Results: A total of 48 tPC measurements were recorded in 12 patients. The median age at initiation of CPD was 8 years and 2 months. The main etiologies were glomerulopathies and structural anomalies. The calculated protein requirements significantly exceeded the established recommendations, except for the 14-15 year old group, which had a statistically significantly lower value. Biochemical parameters remained stable, and height progressed adequately.

Conclusion: Individual estimation of protein requirements based on total protein catabolism was higher than international recommendations. This approach allowed maintenance of growth without metabolic compromise.