LIVER INVOLVEMENT IN EPIDEMIC HEMORRHAGIC-FEVER - IN-SITU HYBRIDIZATION, IMMUNOHISTOCHEMICAL AND PATHOLOGICAL-STUDIES

In the present study, liver biopsy specimens from 37 patients with epi demic haemorrhagic fever (EHF) were investigated by using light and el ectron microscopy, immunohistochemistry fur the EHF virus envelope pro tein G2 and ill situ hybridization (ISH) for EHF viral RNA. Immunostai ning and in situ hybridization were both positive, and a few of the ae tiological agents, the EHF virus (EHFV) particles, were found individu ally within the dilated Golgi cisternae and vesicles, and the dilated rough endoplasmic reticulum of the hepatocyte. The pathological altera tions of the liver cells infected with EHFV were: hepatocellular degen eration, cytoplasmic vacuolation, and spotty necrosis; moreover, zonal necrosis was present and adjacent to the narrowed and occluded sinuso ids. In degenerated and spotty necrotic cells, the positive signals fr om of ISH for EHFV RNA and those from immunostaining for the virus pro tein were both stronger than those in the zonal liver cell necrosis ar ea. The results showed that hepatocellular degeneration and spotty nec rosis might be directly related to the Virus and its duplication insid e the liver cells, while the zonal necrosis was ischaemic and thought to be caused by microcirculation dysfunction.