[Acute hepatitis C--an unresolved issue]

The problem encountered on collecting a large number of cases of acute hepatitis C (AH-C) cases are the reduction in the incidence of new infections, clinically mild or completely asymptomatic disease, and absence of specific diagnostic tests to identify acute HCV infection and to distinguish it from acute exacerbation of chronic hepatitis C (CH-C).

The aim of this paper is to give an overview of 108 patients with AH-C hospitalized at Viral Hepatitis Unit, University Hospital of Infectious Diseases, during a 13-years period. Anti-HCV testing was started in 1990 and detection of HCV-RNA by PCR method in 1995. By epidemiologic data, we were able to distinguish patients with acute posttransfusion hepatitis C (PTH-C) from those with other risk factors. All patients were followed-up at the Outpatient Clinic for Viral Hepatitis in order to diagnose those who would develop persistent HCV infection and CH-C. Thirty-eight patients with acute PTH-C, were followed-up from 1991 till the end of 2003, 82% of them until 1994, because proper anti-HCV blood donors testing started in 1994 in Croatia. All of the patients with acute PTH-C had jaundice.

The development of chronic hepatitis C occurred in 86% of untreated patients with acute PTH-C and 50% of patients treated with recombinant interferon-alfa (3 MU s.c. t.i.w.) monotherapy during six months. The chronic course of disease was recorded in 40% of patients with AH-C and other exposure risk factors. A patient with AH-C after needle-stick injury (HCV genotype 1b) was treated by recombinant interferon-alfa monotherapy (10 MU s.c. once daily) during 3 months without effect, then was switched to combination therapy with recombinant interferon-alfa (5 MU s.c. t.i.w.) + ribavirin 1200 mg daily for 12 months. Another patient with accidental blood exposure refused specific therapy. In the former patient, the treatment with high daily doses of interferon had no led to viral clearance, and virologic response was achieved after 6 months of combination therapy. In the untreated patient, spontaneous viral clearance occurred after 12 months.

There is convincing evidence from published studies that interferon monotherapy reduces the rate of AH-C progression to KH-C. Despite this evidence, there still are many issues that remain to be solved. What is unclear is whom to treat, when to start therapy, and what doses and duration of treatment to use? Maybe 12 months of standard combined therapy (recombinant interferon alfa 5 MU s.c. t.i.w. + ribavirin 800-1200 mg daily) in patients with AH-C genotype 1b is warranted. Evaluation of the efficacy of peginterferon monotherapy or in combination with ribavirin, and comparison of different doses and duration of treatment are needed.