Lipid storage myopathy in familial hyperlipoproteinemia.

We studied a 23-year-old man with lipid storage myopathy. Five members of his family had hyperlipoproteinemia, and his consanguineous parents had elevated serum creatine kinase levels, although only the father showed clinical evidence of myopathy. The patient's intramuscular carnitine content was slightly reduced, but the reduction was not significant compared with the average value for reported cases with carnitine deficiency. Urinary excretion of carnitine showed good responses to starvation, long-chain fatty acid loading, and corticotropin administration. Therefore, his carnitine metabolism was normal. Administration of corticotropin or carnitine did not bring about any improvement of the symptoms. A connection between lipid storage myopathy and hyperlipoproteinemia was suggested.