Thyroid function and anti-thyroid autoantibodies in untreated children with vertically acquired chronic hepatitis C virus infection

OBJECTIVE: The reported data on thyroid function and anti-thyroid autoantibodies in adults with untreated hepatitis C virus (HCV) infection are controversial. Data are scarce for HCV-infected children, and only in those treated with interferon-alpha (IFN-alpha). We investigated thyroid function and anti-thyroid autoantibodies in a cohort of untreated children with vertically acquired, chronic, HCV infection. DESIGN AND PATIENTS: FT4 and TSH serum levels (measured by immunometric assays) and anti-thyroglobulin (TgA) and anti-thyroperoxidase (TPOA) antibodies (evaluated by fluorescence enzymatic immunoassays) were studied in 36 consecutive HCV-infected children and 150 age- and sex-matched controls. The prevalence of thyroid involvement was also related to family history of autoimmune disease, distribution of HCV genotypes, and duration and activity of HCV infection. RESULTS: Four out of 36 (11.1%) HCV-infected children and 4/150 controls (2.7%) showed subclinical hypothyroidism [P = 0.04; relative risk (RR) 4.56, 95% confidence interval (CI) 1.08-19.21]. None of these had anti-thyroid autoantibodies. Two out of 36 (5.6%) HCV-infected children and 1/150 (0.7%) controls had increased TgA values with normal levels of TSH (P > 0.05). Subclinical hypothyroidism and anti-thyroid autoantibodies were not related to family history of autoimmune disease, duration of infection, HCV viral load, liver function or different HCV genotype distribution, but seemed to be related to the presence of active HCV infection. CONCLUSIONS: Our data suggest a role for HCV infection in the development of nonautoimmune thyroid disease in untreated HCV-infected children, confirming previous studies in adults. Clinicians should be aware of thyroid dysfunction even in untreated children.