Hemodialysis (HD) patients often have low serum concentrations of free
L-carnitine and decreased skeletal muscle stores. As
L-carnitine is an essential cofactor in
fatty acid and energy metabolism, it is possible that abnormal
carnitine metabolism in dialysis patients may be associated with clinical problems such as skeletal
myopathies, intradialytic symptoms, reduced cardiac function, and
anemia. Studies have shown that
L-carnitine supplementation in HD patients improves several complications seen in dialysis patients, including cardiac complications (arrhythmias, reduced output, low cardiothoracic ratio), limitation of exercise capacity, increased intradialytic
hypotension, and muscle symptoms. The most promising results have been noted in the treatment of
erythropoietin-resistant
anemia. Routine administration of
L-carnitine to all dialysis patients is not recommended at this time; however, a therapeutic trial of
L-carnitine can be useful in symptomatic patients with certain clinical features unresponsive to the usual measures. These include intradialytic
muscle cramps and
hypotension,
asthenia,
cardiomyopathy, lowered ejection fraction,
muscle weakness or
myopathy, reduced oxygen consumption, and
anemia requiring large doses of EPO.