title: [Serum levels and urine excretion of L-carnitine in patients with normal and impaired kidney function].
abstract: The influence of age, sex, and renal function on serum levels and urinary excretion of free carnitine was studied in 187 subjects. Sixty-one subjects with normal renal function (creatinine clearance greater than 100 ml/min) showed a serum carnitine level of 72.2 +/- 23.2 mumol/l. The carnitine values of males (76.8 +/- 23.3 mumol/l, n = 39) were higher (p less than 0.05) than those of females (64.0 +/- 21.0 mumol/l, n = 22). Carnitine levels did not correlate with age. Values in patients with normal renal function did not differ from serum carnitine levels in healthy controls (74.7 +/- 17.5 mumol/l, n = 49). The mean urinary carnitine excretion per day was 163.5 mumol (range 63.7-419.6 mumol) in patients with intact renal function. Extreme impairment of glomerular filtration rate (creatinine clearance less than 20 ml/min) resulted in higher carnitine concentrations in serum (108.9 +/- 39.4 mumol/l, n = 18, p less than 0.05), lower carnitine elimination per day (78.5 mumol, range 14.5 - 424.3 mumol, n = 18, p less than 0.05) and a decreased carnitine clearance (0.8 ml/min, range 0.2 - 3.8 ml/min). These data together with earlier results obtained in dialysis patients suggest that carnitine metabolism in renal failure is altered by reduction of both endogenous carnitine biosynthesis and renal carnitine clearance.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002331:Carnitine / Q000378:metabolism*; D003404:Creatinine / Q000378:metabolism; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism*; D007677:Kidney Function Tests; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged
chemical_list: D003404:Creatinine; D002331:Carnitine
vernacular_title: Serumspiegel und Urinausscheidung von L-Carnitin bei Patienten mit normaler und eingeschränkter Nierenfunktion.