Plasma carnitine insufficiency and effectiveness of L-carnitine therapy in patients with mitochondrial myopathy.
Plasma carnitine "insufficiency," (plasma esterified carnitine to free carnitine ratio above 0.25) was found in 21 of 48 (43.8%) patients with mitochondrial myopathy, of whom 4 also showed both total and free carnitine deficiencies in plasma. In addition, plasma levels of SCAC and LCAC were higher in patients with mitochondrial myopathy than in controls (P < 0.001 and P < 0.01, respectively). Patients diagnosed as having plasma carnitine insufficiency or deficiency were treated with L-carnitine (50-200 mg/kg per day in four daily doses). Muscle weakness improved in 19 of 20 patients, failure to thrive in 4 of 8, encephalopathy in 1 of 9, and cardiomyopathy in 8 of 8 patients. Plasma carnitine "insufficiency" provides an additional clue to the diagnosis of mitochondrial myopathy and an indication for L-carnitine therapy.
Campos
Y
Y
Centro de Investigación, Hospital 12 de Octubre, Madrid, Spain.
Huertas
R
R
Lorenzo
G
G
Bautista
J
J
Gutiérrez
E
E
Aparicio
M
M
Alesso
L
L
Arenas
J
J
D000293:Adolescent; D000328:Adult; D002331:Carnitine / Q000008:administration & dosage* / Q000097:blood / Q000172:deficiency*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017240:Mitochondrial Myopathies / Q000097:blood* / Q000150:complications / Q000188:drug therapy*; D016896:Treatment Outcome
D002331:Carnitine