ABSTRACT: The renal tubular Fanconi syndrome of children with nephropathic cystinosis causes plasma and musle carnitine depletion. L-Carnitine replacement therapy for up to 18 mo has previously been shown to normalize plasma but not muscle carnitine levels. We treated six cystinosis patients, aged 1 to 4 y, with a mean dosage of 92 mg L-carnitine/kg/d given every 6 h for an average of 62 mo. Despite fractional excretions of free carnitine ranging from 55 to 108%, plasma-free and total carnitine concentrations were maintained at or above normal levels. At the end of the carnitine replacement period, the six children had muscle-free carnitine values ranging from 16.0 to 28.0 nmol/mg noncollagen protein compared with values of 3.0 to 11.4 for cystinosis children not supplemented with carnitine [normal, 22.7 ± 5.0 (SD) nmol/mg protein). Total muscle carnitine values were also normalized by L-carnitine replacement. The monthly increase in total body creatinine production, a measure of muscle mass, was higher (p = 0.036) in children with normal plasma free carnitine concentrations (3.4 ± 0.9 mg/d) than in children with low plasma free carnitine (2.3 ± 0.7 mg/d). No serious side effects, such as severe diarrhea, were observed. We conclude that oral L-carnitine replacement can normalize muscle carnitine content in children with cystinosis.
About this article
Cite this article
Gahl, W., Bernardini, I., Dalakas, M. et al. Muscle Carnitine Repletion by Long-Term Carnitine Supplementation in Nephropathic Cystinosis. Pediatr Res 34, 115–119 (1993). https://doi.org/10.1203/00006450-199308000-00001
Orphanet Journal of Rare Diseases (2016)
Pediatric Nephrology (2011)
Pediatric Nephrology (2006)