Frequency of low carnitine levels in children on dialysis

Abstract

To determine the frequency of low carnitine levels, we measured serum carnitine in pediatric patients on peritoneal dialysis (PD) and hemodialysis (HD). Our prospective cross-sectional study was conducted from September 2004 to March 2005 in a single pediatric center, and included patients under 17 years of age who had been on HD or PD for more than 3 months. Patients with primary carnitine deficiency were excluded. A 4-day food diary was used for carnitine intake quantification. Serum total and free carnitine and acylcarnitine were measured. We compared patients with low and normal carnitine levels using the chi-square test, Mann-Whitney U-test, and Spearman correlation. Of 100 study patients, 70 were on PD, and 61 were male. The median age was 13 years, and the median time on dialysis, 10.5 months. Median serum free carnitine was 32.75 nmol/mL. Carnitine levels were lower than normal in 75 patients and reached the level of deficiency in 29. No difference was found between the dialysis modality types for any fraction of carnitine. No correlation was found between the level of free carnitine and time on dialysis (r = -0.009, p = 0.9) or carnitine intake (r = -0.84, p = 0.4). In conclusion, the frequency ofl ow serum carnitine among pediatric patient on dialysis is high.