Assessment of relationship between nutrition and growth in pediatric hemodialysis patients.

OBJECTIVE: Nutrition and growth are important outcome indicators in pediatric (Ped) hemodialysis (HD) patients. We hypothesized that there is a discrepancy among traditional measures of nutrition, and that adequate nutrition may not reliably predict growth. METHODS: We assessed longitudinal nutrition and growth parameters in 14 Ped HD patients over 1 year. Their age at the end of the study was 15.9 +/- 0.6 years, SEM. RESULTS: For the entire cohort over 1 year, serum albumin (Alb) was 4.3 +/- 0.0 g/dL, and the normalized protein catabolic rate (nPCR) was 1.0 +/- 0.0 (correlation, 0.33; P < .0001). The relationship between Alb and nPCR was significant in only 4/14 (29%). The mean standard deviation and variance were higher for Alb (0.27 +/- 0.03) compared with nPCR (0.18 +/- 0.02). The body mass index percentile (BMI%) was 35.5 +/- 2.9, the percent ideal body weight (%IBW) was 96.2 +/- 1.5, the height-SDS, or standard deviation score (Ht-SDS) was -1.30 +/- 0.11, and the percent weight change (PWC) was +4.9% +/- 1.9%. The highest incidence of reaching our targets for growth was seen for the BMI% (64% of patients) and PWC (79% of patients). The target for Ht-SDS was attained in only 21%. There was a significant negative relationship between Alb and nPCR with BMI%, %IBW, and Ht-SDS, and a significant positive relationship between Alb and nPCR with PWC. CONCLUSION: We conclude that the relationship between Alb and nPCR is weak in individual patients, and that adequate nutrition does not reliably predict growth in Ped HD patients.

Cinacalcet is efficacious in pediatric dialysis patients.

Secondary hyperparathyroidism (high-turnover bone disease, or HTBD) is manifested by elevated parathyroid hormone (PTH) levels. Control of HTBD may be achieved by maintaining low serum phosphorous levels and administering vitamin D therapy, although some patients continue to exhibit high PTH levels. We report the results of the efficacy of the calcimimetic cinacalcet in six hemodialysis (HD) and three peritoneal dialysis (PD) pediatric patients with HTBD, age 14.5 +/- 1.0 (range 7.5-17.5) years. Six patients received 30 mg/day, one required 60 mg/day, and two received 120 mg/day. Treatment with cinacalcet resulted in a 61% decline in intact PTH (iPTH) levels (1,070 +/- 171.5 pretreatment to 417.6 +/- 97.8 posttreatment pg/ml, p = 0.005). Serum alkaline phosphatase also declined (561.8 +/- 169.6 U/L pretreatment to 390.3 +/- 110.3 U/L posttreatment pg/ml). During therapy, serum calcium (p = 0.9) and phosphorous (p = 0.9) levels, calcium-phosphorous product (p = 0.8), systolic blood pressure (BP) (p = 1.0), diastolic BP (p = 0.8), and hemoglobin (p = 0.9) remained unchanged. The dose of oral calcitriol for the three patients on PD while receiving cinacalcet trended downward (0.8 +/- 0.2 pretreatment vs. 0.5 +/- 0.0 microg/day posttreatment pg/ml), as did the dose of paracalcitol for those receiving HD (6.6 +/- 2.3 pretreatment vs. 4.3 +/- 1.7 micrograms/day posttreatment pg/ml). We conclude that short-term treatment with the calcimimetic cinacalcet is efficacious in adolescent dialysis patients.

Successful steroid-sparing treatment of renal limited sarcoidosis with mycophenolate mofetil.

Sarcoidosis is a multi-system disorder characterized by non-caseating epithelioid granulomas in multiple organs. The disease usually presents in young adults and is uncommon in children. Renal involvement can usually occur due to granulomatous interstitial nephritis, but renal failure is uncommon. Corticosteroids are the mainstay of therapy. We present the report of a child with severe renal failure secondary to renal limited sarcoidosis who was successfully treated with corticosteroid induction therapy. Because of the severe side effects of corticosteroids, mycophenolate mofetil was added and corticosteroids were tapered off. The child has been in sustained remission for over a year with mycophenolate mofetil monotherapy.

Hyperphosphatemia due to fosphenytoin in a pediatric ESRD patient.

Fosphenytoin is indicated for the treatment of generalized convulsions and seizures occurring during neurosurgery. Metabolites of fosphenytoin include phenytoin, phosphate, and formaldehyde. The drug monograph recommends caution in administering fosphenytoin to patients in whom phosphate restriction is necessary. Additionally, fosphenytoin has altered pharmacokinetics in end-stage renal disease patients. We report a 17-year old African-American male with end-stage renal disease who developed acute hyperphosphatemia to 3.9 mmol/L (12.1 mg/dL) following the intravenous administration of 1000 mg of fosphenytoin for an idiopathic complex partial seizure. To our knowledge, this is the first report of acute hyperphosphatemia due to fosphenytoin administration. Due to this risk of hyperphosphatemia, we recommend that fosphenytoin should be used with caution in the end-stage renal disease population.