A histopathological study of the liver lesion in paraquat poisoning

An analysis of twenty autopsy cases with emphasis on bile duct injury

Abstract

A histopathological study of the liver lesion in paraquat poisoning was performed on twenty autopsy cases of paraquat poisoning light microscopically. Seventeen cases showed hepatocytic injury, which was the lesion previously reported by many authors.
Eight cases revealed bile duct injury, which consisted of epithelial changes showing hydropic degeneration and necrosis. In mild injury, the epithelium showed hydropic degeneration. The injury was observed in the extrahepatic bile duct and in gallbladder as well as in the intrahepatic bile ducts which have larger caliber than the small interlobular bile ducts. According to the increasing of the injury, necrotic epithelium gradually increased, and not only those areas mentioned above but also bile ductules were injuried. The severity of the injury increased gradually from the bile ductules or small interlobular bile ducts to a intrahepatic large bile duct. The injury of the same degree was seen in the bile ducts which have larger caliber than the large bile duct and in gallbladder. In severe injury, cholestasis occurred in the interlobular and septal bile ducts. It is considered that the cholestasis was the result of epithelial necrosis in the ducts and stenosis of their lumen by debris.
Nine cases showed centrolobular cholestasis. The cause of the cholestasis was not clearly understood in this study.