Introduction: Chronic treatment with parenteral nutrition (PN) has been associated with renal complications, including hypercalciuria, nephrocalcinosis, glomerular proteinuria and reduced glomerular filtration rate (GFR). Some pediatric studies reported high prevalence of proteinuria and renal complications, but evidence is scarce and mostly short-termed. Thus, our aim was to evaluate renal complications in children with intestinal failure, receiving long term treatment with PN.

Methods: A cross sectional retrospective study was performed (in the period of 5.2017 until 12.2018), using electronic medical records of patients treated in our pediatric intestinal failure clinic for more than 1 year. Data was collected regarding medical background, anthropometric measurements, blood and urine tests and abdominal sonography.

Results: Complete data was available for 15 children (67% males), with median age of 6 years (ranged 1.5 to 15 years). Median duration of PN treatment was 4 years (IQR 1.5-6 years). All patients had normal blood pressure for age and height. Low grade proteinuria was identified in 61% and mild albuminuria in 30% of the cohort. Hypercalciuria was present in 50% and hyperoxaluria in 46% of the patients. Only one patient had nephrocalcinosis as noted on renal sonography. Estimated glomerular filtration rate (eGFR) was normal in all but one patient, who had preexisting renal disease.

Conclusions: Pediatric patients with intestinal failure can present with preserved kidney function after years of PN treatment. Among this age group, eGFR is normal in the absence of preexisting kidney disease. Despite high prevalence of hypercalciuria, nephrocalcinosis is rare. Continued monitoring of renal function, urinary protein excretion and metabolic urine parameters, and examining larger long-term cohorts are essential in order to characterize effects of prolonged PN on different kidney functions in pediatric patients.