Clinical and virologic features of hepatitis C virus infection associated with intravenous immunoglobulin.

Objective: To characterize the clinical features of hepatitis C virus (HCV) infection associated with the administration of intravenous immunoglobulin (IVIG) in patients with varied immunodeficiencies.
Design: Prospective collection of clinical and virologic data in patients determined to have HCV exposure associated with Gammagard.
Setting: Outpatient department of Children's Hospital, Boston.
Patients: Twenty-one patients with evidence of HCV infection were identified during a screening program initiated to detect infection in exposed individuals. They ranged from 5 to 53 years of age; 14 were children under age 18.
Results: Six patients presented with severe clinical hepatitis before detection by screening, 13 were detected by screening only, and 2 were first detected by screening and subsequently developed symptomatic hepatitis. Follow-up is available on 20 patients; 4 without viremia at identification have remained clinically well. Hepatitis and viremia have resolved in 2, 2 additional subjects have developed normal alanine aminotransferase (ALT) values with persistent viremia, and 13 have biochemical and/or virologic evidence of chronic hepatitis. Eight patients (7 children) have undergone liver biopsies; 7 have histologic findings of chronic hepatitis, 5 have mild fibrosis, and 2 have moderate fibrosis. HCV genotypes 1a and 1b were observed with equal frequency in this group.
Conclusions: Some HCV infections associated with IVIG had a more severe, acute course than is ordinarily described. This may be attributable to host factors, such as immunodeficiencies, or virologic factors, such as inoculum or genotype. Although a large percentage (87.5%) of these individuals developed chronic infection, the natural history is not as yet completely defined.