IgM antibody response to the hepatitis C virus core protein in intravenous drug users.

To verify whether a solid-phase enzyme immunoassay for serum IgM antibodies to the hepatitis C virus (HCV) core protein (IgM anti-HCVcore) might be proposed as a surrogate test for serum HCV RNA, we studied 86 anti-HCV antibody-positive intravenous drug users. Serum HCV RNA was demonstrated by RT-PCR with primers derived from the 5' non-coding and the core region. IgM anti-HCVcore antibodies were found in 62/86 (72%) subjects; circulating HCV RNA was detected by the 5' noncoding assay in 53/86 samples (62%) and by the core region assay in 35/86 samples (41%). IgM anti-HCVcore reactivity was associated with core HCV RNA seropositivity (p < 0.05) but not with 5' noncoding HCV RNA seropositivity (p = NS). Patients infected by HCV type 1a were more-often positive for IgM anti-HCVcore (p < 0.05) and for core HCV RNA (p = 0.005) than patients infected by other HCV genotypes. IgM anti-HCVcore reactivity was significantly more common in subjects positive for core HCV RNA (p < 0.005) and in subjects aged > 30 years (p < 0.05). In conclusion, the IgM anti-HCVcore assay frequently tests positive in intravenous drug users, particularly when infected by HCV 1a, but is not a surrogate of testing for serum HCV RNA.

High prevalence of infection with hepatitis G virus in patients with hepatic and extrahepatic malignancies.

BACKGROUND/AIMS: The pathogenic role of hepatitis G virus, the recently discovered blood-borne agent, is controversial. Our aim was to ascertain the prevalence of hepatitis G virus infection in hepatic and in extrahepatic malignancies. METHODS: We studied 166 Italian patients (112 male, 54 female, mean age 61.8+/-9.3, mean+/-SD, range 34-85). One hundred and eighteen had cirrhosis, which was complicated by hepatocellular carcinoma in 66 cases. Forty-eight patients had extra-hepatic malignancies. Circulating HGV RNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) of both the nonstructural-3 and 5'noncoding regions of the hepatitis G virus genome. Antibodies to the E2 protein of hepatitis G virus were detected by means of an enzyme-linked immunosorbent assay. RESULTS: Ongoing HGV infection was detected in 30/66 (46%) patients with hepatocellular carcinoma, 12/52 (23%) patients with cirrhosis, and 14/48 (29%) patients with extrahepatic malignancies (p<0.05). Evidence of exposure to hepatitis G virus (detection of either HGV RNA or anti-E2 antibodies) was found in 46% of patients with cirrhosis, 66% of patients with hepatocellular carcinoma, and 39% of patients with extrahepatic malignancies. Serum HGV RNA positivity was associated with a hematocrit value < or = 0.35 and with history of exposure to blood products (p<0.005). CONCLUSIONS: Ongoing hepatitis G virus infection is detected at a very high rate in patients with hepatocellular carcinoma, but is also fairly common in extrahepatic malignancies. Hepatitis G virus infection in these patients is likely to originate from exposure to blood products, and to persist because of deficient immune surveillance.