title: Quantification of serum HCV core antigen by a fluorescent enzyme immunoassay in liver transplant recipients with recurrent hepatitis C--clinical and virologic implications.
abstract: BACKGROUND
  Monitoring hepatitis C viremia may be useful in the management of liver transplant patients with recurrent hepatitis C virus (HCV) infection. The clinical utility of a newly described fluorescent enzyme immunoassay for the detection of serum HCV core antigen was evaluated.
  
  
  METHODS
  Serum samples prospectively collected from 57/63 consecutive patients transplanted for HCV-related end-stage liver disease were assayed for both serum HCV core antigen by fluorescent enzyme immunoassay and HCV RNA level using a branched chain DNA signal amplification assay. HCV genotype was determined by restriction fragment length polymorphism analysis based on 5' untranslated region. One- and 2-year annual protocol liver biopsies from these patients were graded for inflammation, fibrosis, and cholestasis
  
  
  RESULTS
  Serum HCV core antigen and HCV RNA were detected in a similar proportion of samples (256/ 281 vs. 260/281, P=NS), and there was an excellent correlation between assays (r2=0.905, P<0.0001) independent of HCV genotype. A conversion equation between HCV core antigen and HCV RNA was constructed to estimate the HCV core antigen to RNA ratio to be around 231 to 1. Mean serum HCV core antigen levels peaked initially at 3 months posttransplant but there was significant interpatient variation as to when peak levels occurred. A high serum HCV core antigen level in the first 6 months was associated with histological deterioration in terms of bridging fibrosis, cirrhosis, severe cholestasis, or retransplantation by 2-year follow-up.
  
  
  CONCLUSIONS
  Determination of serum HCV core antigen level reflects HCV viremia and may have clinical implications in liver transplant patients with HCV recurrence.
authors.affiliation: Section of Hepatobiliary Diseases, Division of Gastroenterology, Hepatology and Nutrition, University of Florida College of Medicine, Gainesville, USA.
authors.forename: R C
authors.initials: RC
authors.lastname: Dickson
authors.forename: M
authors.initials: M
authors.lastname: Mizokami
authors.forename: E
authors.initials: E
authors.lastname: Orito
authors.forename: K P
authors.initials: KP
authors.lastname: Qian
authors.forename: J Y
authors.initials: JY
authors.lastname: Lau
mesh_terms: D000328:Adult; D005455:Fluorescent Antibody Technique; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000175:diagnosis* / Q000601:surgery*; D018936:Hepatitis C Antigens / Q000097:blood; D006801:Humans; D016031:Liver Transplantation; D011183:Postoperative Complications / Q000175:diagnosis; D012367:RNA, Viral / Q000097:blood; D012008:Recurrence; D013997:Time Factors; D014758:Viral Core Proteins / Q000097:blood*; D014766:Viremia / Q000175:diagnosis
chemical_list: D018936:Hepatitis C Antigens; D012367:RNA, Viral; D014758:Viral Core Proteins; C069130:nucleocapsid protein, Hepatitis C virus