Yong-Yuan Zhang

Serum HCV RNA Levels in Patients with Chronic Hepatitis C Given a Second Course of Interferon alpha-2b Treatment after Relapse following Initial Treatment

10 patients with chronic hepatitis C virus (HCV) infection who previously had responded temporarily to 9 months interferon alpha-2b treatment with normalization of ALT levels during treatment but later relapse were given a second 6-month treatment course. All patients were positive for anti-HCV by a second generation ELISA confirmed by second generation RIBA and positive for HCV RNA in serum before retreatment with interferon. Serum HCV RNA titers and ALT levels were monitored before, during and after treatment. ALT levels fell significantly from mean 1.95 mu kat/l before treatment to mean 0.96 and 0.85 mu kat/l after 4 and 24 weeks treatment, respectively (p < 0.005-p < 0.009). Six patients had normal ALT levels (< 0.07 mu kat/l) at treatment stop. 12 weeks post treatment cessation, however, the mean ALT level, 2.29 mu kat/l, was not significantly changed from the pretreatment level and all patients had raised ALT levels. The mean pretreatment HCV RNA titer in serum 10(5) (range 10(7)-10(3.5)) fell in all patients to mean 10(1.3) (range 10(3)-10(0)) already after 4 weeks treatment and became undetectable at treatment cessation in 5 patients, of whom 4 had normal ALT levels. ALT levels, however, were also normal in 2/5 patients who continued to have detectable HCV RNA titers at treatment cessation. After treatment was stopped HCV RNA titers rose again and 12 weeks post treatment the mean titer was 10(4.7) (range 10(3.5)-10(5.5)).(ABSTRACT TRUNCATED AT 250 WORDS)

At least three hepatitis C virus strains implicated in Swedish and Danish patients with intravenous immunoglobulin-associated hepatitis C

BACKGROUND: Three reported Swedish cases of hepatitis C in patients receiving an intravenous immunoglobulin (Gammagard, Baxter Healthcare, Deerfield, IL) were among the first to bring to light a worldwide outbreak of hepatitis C associated with non‐solvent/detergent (SD)‐treated Gammagard. In February 1994, all implicated batches of Gammagard were recalled and exposed patients traced.

Hepatitis C virus antibodies and hepatitis C virus RNA in Chinese blood donors determined by ELISA, recombinant immunoblot assay and polymerase chain reaction

Antibodies to hepatitis C virus (anti‐HCV) were determined in Chinese blood donors from the city of Wuhan by a second generation ELISA screening test and a confirmatory recombinant immunoblot assay (RIBA II). Two materials of 281 and 222 sera were sampled under similiar conditions in 1989 and 1990, respectively. The first collection of sera was sent to Sweden in lyophilized form, the second directly as fresh unfrozen sera. A high proportion (7.1%) of the lyophilized sera reacted positively in the anti‐HCV screening assay, but only seven (2.5%) were positive by the RIBA confirmatory test. In four of these sera HCV‐RNA could be detected by polymerase chain reaction (PCR) analysis. In the second material of fresh sera six reacted positively in the screening anti‐HCV ELISA, but only one was RIBA positive and four were RIBA indeterminate. None of these sera was positive for HCV‐RNA. Thus, the overall prevalence of anti‐HCV among the 503 Chinese blood donors, as identified by RIBA, was 1.6%, and of HCV‐RNA by PCR 0.8%. The confirmed antibody prevalence is higher than reported from the Western world. Caution about using data from the screening ELISA only, especially if sera have been handled in an unorthodox way, is emphasized.

2‘,3’‐dideoxy‐3‘‐fluoroguanosine inhibits duck hepatitis B virus in vivo

SUMMARY. Duck hepatitis B virus (DHBV) belongs to the same virus family as the human hepatitis B virus (HBV). Domestic ducks infected with DHBV can be used as an animal model for chronic hepatitis B virus infection in therapeutic trials. In this study the antiviral effect of the guanosine analogue 2′,3′‐dideoxy‐3′‐fluoroguanosine (FLG) was tried in vivo on chronically DHBV‐infected ducks. The ducks were either congenitally infected, or inoculated with DHBV immediately post‐hatch. FLG was given as intraperitoneal injections twice daily, at different dosages. Serum DHBV levels were determined by DNA dot‐blot hybridization. A strong inhibition of serum DHBV DNA was observed with FLG doses down to 1 mg kg‐1 day‐1. given for 7 to 10 days. With the corresponding thymidine analogue, 2′,3′‐dideoxy‐3′‐fluorothymidine; however, no inhibition was obtained. This difference may be due to different phosphorylation mechanisms. Independently of FLG dose, serum DHBV DNA returned to pretreatment levels within a few days after cessation of therapy. After a long‐term trial (FLG, 5mg kg‐1 day‐1 for 33 days), the same relapse of DHBV production was seen. Thus, FLG is an efficient inhibitor of DHBV replication, and is a candidate for treatment of HBV infections. However, the effect is transient, and therefore combination with other types of anti‐HBV drugs should be considered.