[Symposium: Current evaluation of diagnostic methods on viral hepatitis type C and consequent clinical features]

In this symposium, the speakers have discussed the progress of the current diagnostic methods available for the diagnosis of viral hepatitis type C, and the accuracy and reproducibility at hand now, or which should be attained in the near future. Since the first appearance of ELISA (Ortho) and RIA (Dainabot) kit, the screening of infected blood with HCV from donors has been very successful. Posttransfusion hepatitis following infected blood transfusion has clearly decreased. The carrier rate of HCV in the Ehime prefecture is reported to be 1.85% in males and 1.25% in females. Diagnostic methods of the second generation such as ELISA and RIBA using C200 and C22 (core) protein as antigens yield 92.6 to 100% positive results in a diagnosis of NANB hepatitis following anti-hemophilic sera injection or hemodialysis. Detection of HCV RNA by RT-PCR procedure promised accurate diagnosis. Using such diagnostic methods, the majority of the patients with NANB chronic hepatitis were diagnosed as having CH type C. IgM anti-C 100-3 antibody was not useful for early diagnosis of patients infected with HCV, but the titer was useful for determining the therapeutic response of patients on INF therapy. The route of infection was concluded to be mostly horizontal rather than vertical (maternal-child), though a few cases were present suggestive of maternal transmission. Interferon therapy against patients with CH type C was effective in CAH 2A, but only a poor response was observed in patients with CAH 2B.