Acute veno-occlusive disease of the liver: fine structure in Jamaican children

ABSTRACT

Electron microscopic observations in humans veno-occlusive disease (VOD) of the liver are presented for the first time . Marked endothelial damage was seen in the sinusoids and subterminal and terminal hepatic veins, accompanied by extravasation of erthrocytes into Disse's space and naked hepatocytes showing a reduction in microvilli. Endothelial damage was seen in all zones of the liver. At the level of terminal hepatic veins, the closed structure of these vessels, absence of fenestrations, existence of a basement membrane, and the presence of collagen and connective tissue cells in the wall provide resistance to erthrocytes and cellular debris tracking up Disse's space. These factors tend to result in narrowing of the lumen where the sinusoid enters the vein. Parenchymal cell alterations, at the time of the biopsies, included dilation of bile canaliculi, abundant glycogen, and nuclear invaginations.(AU)