Enteral nutrition and the risk of nephrolithiasis in complex pediatric patients.

PURPOSE: Medically complex, non-ambulatory children can often suffer from nephrolithiasis. The purpose of this study is to determine risk factors which are predictive for recurrent stone formation in this patient population. MATERIAL AND METHODS: A retrospective cohort study was performed on non-ambulatory patients with cerebral palsy and/or severe developmental delay presenting to a high-volume Pediatric Stone Center from 2015 to 2019. Two 24-hour urine collections were performed as a baseline prior to pharmacotherapeutic and/or dietary intervention. Healthy stone-forming children served as a control group. RESULTS: 28 non-ambulatory subjects and 38 healthy controls were evaluated. The study group had a higher rate of bilateral nephrolithiasis but a similar history of previous surgical procedures. 89% of the non-ambulatory children were fed via a gastrostomy. The median calcium excretion was the same in both groups (3.0 mg/kg/day). The median 24-hour excretion of oxalate was significantly increased in the study group (54 vs 31 mg/1.73 m2/day, p = 0.0001). Urinary citrate and phosphorus excretions, and the supersaturations of calcium oxalate and calcium phosphate were similar between study subjects and controls. Calcium oxalate stones were noted in 57% of those with known stone composition in the study group. Enteral feeding formulas were primarily based on soy protein, a known high oxalate food. CONCLUSIONS: Urinary oxalate excretion is significantly increased in a cohort of medically complex, non-ambulatory stone-forming children. Urinary calcium excretion was not elevated between study subjects and healthy controls. Further analysis is needed to assess if dietary intervention to limit oxalate excretion results in decreased stone formation.

Does a Multidisciplinary Pediatric Stone Center Improve Outcomes?

INTRODUCTION: Urolithiasis is becoming more prevalent in children in the United States. A multidisciplinary pediatric stone center was initiated in 2014 to address this growing public health issue. The purpose of this manuscript is to assess the development of the stone center and its clinical outcomes. METHODS: A retrospective cohort study was performed to assess clinical outcomes. Inclusion criteria included patients younger than 21 years of age with more than 6 months of followup. Data abstracted from the medical record included patient demographics, medications, imaging, metabolic evaluations, surgical procedures, and emergency department visits. The number of surgical procedures, emergency department visits, and computerized tomography scans were compared before and after the first visit to the stone center. RESULTS: A total of 353 patients were evaluated in the stone center during the study period, 264 (98 male, 166 female) of whom met inclusion criteria. The mean age was 14.5 years, and the mean followup was 1.1 years. Of all patients 60% had a metabolic abnormality. Prior to the first visit 104 patients underwent surgery. Surgical procedures decreased from 39% to 17% during the year before and at any time after the first visit (p <0.0001). Emergency department visits per year decreased from 1.4 to 0.6 before and after the first visit (p <0.0001). Computerized tomography scan use decreased from 32% to 24% (p=0.3). CONCLUSIONS: A multidisciplinary stone center can be a feasible option to coordinate care and improve clinical outcomes. In our series the number of surgical procedures and emergency department visits decreased after enrollment.