DETECTION OF HEPATITIS-C AFTER LIVER-TRANSPLANTATION - 4 SEROLOGIC TESTS COMPARED

To determine the best method for detecting HCV infection in immunosupp ressed patients, stored frozen serum from 101 liver transplant recipie nts was tested for hepatitis C virus. Each sample was tested by four a ssays. HCV RNA was detected by both polymerase chain reaction (PCR) an d branched DNA signal amplification. Antibody to HCV was determined us ing second-generation enzyme-linked immunoassay (EIA) and recombinant immunoblot assay. Forty one transplant recipients met the working defi nition for true positives of HCV infection. Of these ''true positives, '' 98% were positive by HCV RNA PCR assay, 88% by b-DNA signal amplifi cation assay, 88% by anti-HCV EIA, and 63% demonstrated two or more re active bands on recombinant immunoblot. Five of 57 (9%) HCV-antibody n egative recipients had HCV RNA detected by both methods. Of 44 HCV enz yme-linked immunoassay (EIA) repeatedly reactive samples, the recombin ant immunoblot was negative in 2 and indeterminate in 13. HCV RNA was present in 9 of 13 recombinant immunoblot indeterminate sera. Nine EIA repeatedly reactive sera were negative by both tests for HCV RNA. In liver transplant recipients, HCV infection is best determined by measu rement of HCV RNA. Antibody formation may be delayed or suppressed in a minority of patients despite >10(9) equivalents/L (>10(6)/mL) of HCV RNA in serum. Recombinant immunoblots with a single reactive band pat tern often indicate HCV infection in immunosuppressed patients.