Liver ultrastructure in psoriatics related to methotrexate therapy. 1. A prospective study of findings in hepatocytes from 24 patients before and after methotrexate treatment.

To show what damage occurs in the hepatocytes of psoriatics receiving Methotrexate (MTX) therapy liver biopsies from 24 psoriatics with severe psoriasis before and after MTX therapy were studied blind by light and electron microscopy. We also aimed to determine the severity of lesions and find possible correlations, and to seek a relationship of these observations with light microscopical and clinical findings. The present study has shown that MTX probably caused damage to the hepatocytes reflected in the membrane whorls (p less than 0.05) and the accumulation of lipid droplets (p less than 0.05). There was an increase (p less than 0.05) in autophagic vacuoles, which mostly contained glycogen and cell sap with residual bodies. These residual bodies were then found in an increased number in the nearby Kupffer cells. Crystals were found in megamitochondria in most patients before and after MTX therapy. Some of these crystals were found free in the cytoplasm. Mitochondria containing crystals were shown in autophagic vacoules, representing possible pathways of their breakdown. Bile canaliculi commonly contained debris but only one patient had evidence of cholestasis. There was no significant change in nuclei, Golgi apparatus, or the endoplasmic reticulum and no statistically significant correlation between the shown changes and the total dose of MTX given.