Carnitine and carnitine esters in plasma and adipose tissue of chronic uremic patients undergoing hemodialysis.

Carnitine concentrations were measured in the plasma and adipose tissue of seven chronically uremic and hyperlipidemic patients undergoing hemodialysis. Plasma levels of carnitine had dropped by the end of dialysis. The clearance of free carnitine was greater than that of acylcarnitine. Fasting plasma free carnitine, long-chain acylcarnitine, D-beta-hydroxybutyrate and free fatty acid concentrations were normal but short-chain acylcarnitine values were elevated. In adipose tissue, total carnitine concentrations were normal but long-chain acylcarnitine concentrations were increased. These findings may indicate a hypermetabolic state in which the acute removal of carnitine during hemodialysis may lead to a critical shortage of this substance.