Hepatic ultrastructural changes and liver dysfunction in amyotrophic lateral sclerosis.

Ultrastructural changes of hepatocytes were studied in liver biopsy specimens obtained from 21 patients with amyotrophic lateral sclerosis (ALS). In all specimens, one or more of the following abnormal findings were made: bizarre giant mitochondria; intramitochondrial paracrystalline inclusions; disorganization of the lamellar structure of rough endoplasmic reticulum; increased numbers of smooth endoplasmic reticulum; and/or parasinusoidal fibrosis. Above all, paracrystalline inclusions appeared to be a highly specific finding in ALS. In light of the above pathologic findings, we evaluated the liver function tests of 37 patients (including the above-mentioned 21 patients) with ALS, and found a high incidence of mild liver dysfunction. In spite of its subtleness, these ultrastructural changes of hepatocytes were consistently found in such patients, and offer further insight into the intrahepatic metabolic abnormalities in ALS.