Evaluation of antibodies to hepatitis C virus in a long-term prospective study of posttransfusion hepatitis among thalassemic children: comparison between first- and second-generation assay.

During an 8-year prospective study of post-transfusion hepatitis conducted at the Thalassemic Center of Cagliari (Italy), including 135 newly diagnosed thalassemic children on long-term transfusion maintenance, 83 children (61%) developed non-A, non-B hepatitis (NANBH). Resolution of NANBH was observed in 17 (20%) cases, and chronicity in 57 (69%), whereas the remaining 9 (11%) experienced one or two additional bouts of acute NANBH. Of the 83 children with NANBH, 75 (90%) showed anti-hepatitis C virus (HCV) seroconversion when tested by second-generation enzyme-linked immunosorbent assay (ELISA), whereas first-generation ELISA showed anti-HCV in only 59 (71%) cases (p = 0.003). Moreover, the newly developed assay allowed an earlier detection of anti-HCV response in most of the patients who seroconverted by both assays, reducing significantly the mean onset-seroconversion interval (5 +/- 9.4 weeks vs. 14.5 +/- 20.8 weeks, p < 0.05). It was significantly more sensitive for the identification of HCV infection, not only in resolving NANBH, but also in NANBH progressing to chronicity (79 vs. 35%, respectively, p = 0.008; and 93 vs. 79%, p = 0.028). The pattern of antibody response with first-generation assay was characterized by clearance of anti-HCV with time, in most of the patients who recovered, and by persistence of anti-HCV in the majority of those who progressed to chronicity, whereas second-generation ELISA usually showed persistence of anti-HCV over time, regardless to the outcome of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)