Acute Hepatitis E. virus infection in Egypt

Abstract

Hepatitis E virus (HEV) is largely responsible for water borne epidemics in many developing countries. The principle mode of HEV transmission is the fecal oral route in epidemic and sporadic forms with a high case fatality ratio in pregnant women. Serum samples from 50 healthy subjects and from 435 acute viral hepatitis patients, 4-75 years old, were screened for markers of acute viral hepatitis. These included (HB s Ag, anti-HBc (IgM), anti-HDV (IgM), HAV (IgM), anti-HCV (IgG), and anti-HEV (IgG), and (IgM) tests by enzyme-linked immunoassays (EIA). Furthermore isolation of HEV from peripheral blood lymphocytes and from stools belonging to anti-HEV IgG-positive patients was attempted by inoculation of HepG 2 and Vero cell line cultures. The inoculated cell cultures were examined after immunoperoxidase staining for the detection of HEV antigen. Plasma, lymphocytes and stool samples from anti-HEV IgM positive patients were examined for HEV RNA by PCR. Anti-HEV IgG was found in 144/435 (33%) of these acute hepatitis patients. Anti-HEV (IgM) was detected in 8/52 (15.4%) out of 52 chosen from the 144 sera that were anti-HEV IgG positive cases. HEV was isolated in HepG 2 from 32.6% of lymphocyte and from 34.9% of stools from patients positive for anti-HEV (IgG). While it was isolated from 71.4% of lymphocytes and from 100% of stools from patients positive for anti-HEV (IgM). In Vero cell cultures there was no HEV isolation from stools but HEV was isolated from 50% of lymphocytes. HEV RNA was detected by PCR in 85.7% of stools, 62.5% of plasma, and in 37.5% of lymphocyte samples belonging to anti-HEV IgM positive cases. Analysis of these diagnostic tests indicated that virus isolation from peripheral blood lymphocytes and stools by inoculation of HepG 2 cell cultures is more sensitive than virus-RNA detection by PCR