title: Role of hepatitis E virus antigen in confirming active viral replication in patients with acute viral hepatitis E infection.
abstract: BACKGROUND
  Demonstration of active viral replication is important in serologically confirmed cases of hepatitis E virus (HEV) infection to assess prognosis. Detection of HEV RNA by reverse transcriptase polymerase chain reaction (rtPCR) is the gold standard for demonstration of active viremia.
  
  
  OBJECTIVE
  The present study was designed to compare the diagnostic utility of HEV antigen (Ag) with HEV IgM and HEV rtPCR in detecting the active viral replication.
  
  
  METHODS
  Blood samples from 156 probable cases of acute viral hepatitis (AVH) were collected. Screening for hepatitis B surface antigen (HBsAg), antibody to hepatitis C virus (anti HCV), IgM antibody to hepatitis A virus (HAV IgM) was done on the Architect platform (Abbott Laboratories, IL, USA). HEV IgM ELISA (Wantai Biological, Beijing, China), HEV-Ag ELISA (Wantai Biological, Beijing, China) and HEV rtPCR were done on all the samples.
  
  
  RESULTS
  Out of 156 AVH cases in 56 (35.8%) a diagnosis of HEV was confirmed. Positivity being; anti-HEV IgM 44/56, HEV RNA 20/56, and HEV antigen 17/56 in established cases. Male to female ratio was 3:1. The median age was 40 (range 14-71) years. HEV Ag showed a good concordance with HEV RNA (k=0.635, p<0.001). However HEV IgM did not show any concordance with HEV RNA (k=0.14).
  
  
  CONCLUSIONS
  HEV antigen assay can be used as an additional diagnostic marker to confirm active viral replication in serologically positive samples.
authors: Department of Virology, Institute of Liver & Biliary Sciences (ILBS), Vasant Kunj, New Delhi 110070, India. Electronic address: ektagaurisha@gmail.com.
authors: Ekta
authors: E
authors: Gupta
authors: Priyanka
authors: P
authors: Pandey
authors: Shivani
authors: S
authors: Pandey
authors: Manoj Kumar
authors: MK
authors: Sharma
authors: Shiv Kumar
authors: SK
authors: Sarin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000956:Antigens, Viral / Q000096:biosynthesis / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006508:Hepatitis Antibodies / Q000097:blood; D016751:Hepatitis E / Q000175:diagnosis* / Q000821:virology; D016752:Hepatitis E virus / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007159:Immunologic Tests / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014779:Virus Replication; D055815:Young Adult
chemical_list: D000956:Antigens, Viral; D006508:Hepatitis Antibodies; D007075:Immunoglobulin M; D012367:RNA, Viral
keywords: Acute viral hepatitis; Anti-HEV IgM; HEV RNA; HEV antigen