Interferon therapy for acute posttransfusion non-A, non-B hepatitis: response with respect to anti-hepatitis C virus antibody status.

To assess the effect of interferon therapy on posttransfusion non-A, non-B acute hepatitis, we examined the appearance of serum hepatitis C virus antibody (anti-HCV) and abnormal serum aminotransferase levels after the onset of hepatitis in 12 patients treated with interferon and in 46 patients treated conservatively. Eleven patients were given 3 million units of human fibroblast beta-interferon three times weekly for 4 wk and 1 was given one million units of human lymphoblastoid alpha-interferon daily for 3 months. In the interferon-treated patients, the effect of therapy on hepatic histology was also assessed. Detection of anti-HCV within 6 and 12 months after the onset of hepatitis was less common in interferon-treated patients than in control patients (6/12 vs 35/46 and 5/12 vs 35/46, both p = NS). At 24 months after the onset of hepatitis, anti-HCV levels were significantly lower in interferon-treated patients (0/10, p less than 0.05), but had not changed significantly in control patients (34/46). Abnormal serum aminotransferase levels at 6, 12, and 24 months after the onset of hepatitis were significantly less common in interferon-treated patients than in controls (25% vs 78.3%, p less than 0.005; 25% vs 71.7%, p less than 0.01; and 0% vs 67.4%, p less than 0.001). The percentage of abnormal serum aminotransferase levels at 6, 12, and 24 months after onset of hepatitis was also less in interferon-treated patients than in control patients, both among anti-HCV-positive patients (50% vs 85.7%, p = NS; 50% vs 80%, p = NS; and 0% vs 77.1%, p less than 0.01) and among anti-HCV-negative patients (0% vs 54.5%, p = NS; 0% vs 45.5%, p = NS; and 0% vs 27.3%, p = NS). Immediately after interferon therapy, the histological activity index dropped from 6.0 +/- 4.2 to 4.8 +/- 2.5 in anti-HCV-positive patients (p = NS) and from 4.2 +/- 4.3 to 2.6 +/- 1.7 in anti-HCV-negative patients (p = NS). Biopsy specimens obtained from four patients 12-23 months after interferon therapy revealed normal histology in one anti-HCV-positive patient and two anti-HCV-negative patients, and marked improvement in the other anti-HCV-positive patient. These results indicate that short-term, low-dose interferon therapy may be effective for posttransfusion non-A, non-B acute hepatitis (both anti-HCV-positive and anti-HCV-negative).