Fine structural changes in the liver of methotrexate-treated psoriatics

Ultrastructure of 55 liver biopsies obtained from 52 patients, all but 1 with psoriasis and all but 5 treated with methotrexate (MTX), have been studied. In MTX-treated psoriatics, liver cell nuclei showed reduced electron opacity with frequent cytoplasmic invaginations and glycogen inclusions. In the mitochondria nonspecific changes, such as pleomorphism, gigantism, paracrystalline inclusions, compartmentalization, signs of division and sequestration via autophagosomy were noted. The pericanalicular ectoplasm exhibited widening with accumulation of microfilaments. Detachment of desmosomal plaques between hepatocytes was common. A striking finding was the hyperplasia of fat-storing perisinusoidal (Ito) cells. No definite correlation was found between morphology, duration of disease, treatment as well as cumulative dose of MTX.