Background: Autoimmune thyroid disease and thyroid dysfunction are common in adults receiving interferon (IFN)-based treatment for chronic hepatitis C (CHC). Few data are available in children with CHC. This study is aimed to evaluate the appearance and timing of thyroid dysfunction and antithyroid autoimmunity in children with CHC treated with pegylated IFN-α-2b and ribavirin (RBV).
Methods: Sixty-one otherwise healthy children with CHC, 3-17 years of age, infected perinatally and treatment naïve, receiving therapy with pegylated IFN-α-2b and RBV and 183 age- and sex-matched controls were included in a multicenter, prospective, case-control study. Thyroid-stimulating hormone, free thyroxine, antithyroglobulin antibodies and antithyroid peroxidase antibodies were assessed before, during and 24 weeks after the end of treatment.
Results: From baseline to the end of treatment, subclinical hypothyroidism and autoimmune thyroiditis were diagnosed in 17 of 61 (27.94%) and in 4 of 61 (6.6%) of the children treated, respectively, and in 5 of 183 (2.7%) and in none of the controls (P < 0.0001, relative risk: 10.2, 95% confidence interval: 3.9-26.5; P = 0.03, relative risk: 26.8, 95% confidence interval: 1.5-489.1, respectively). Twenty-four weeks after the end of treatment, subclinical hypothyroidism persisted in only 4 of 61 (6.6%). Autoimmune thyroiditis persisted in 3 of 4 (75%) of the cases.
Conclusions: Subclinical hypothyroidism is common in children with CHC receiving treatment with pegylated IFN-α-2b and RBV, but in most cases is transient. Autoimmune thyroiditis, which is less common, generally persists after treatment completion. Thyroid function should be carefully monitored in patients presenting with antithyroid autoantibodies and thyroid dysfunction during and after pegylated IFN-α-based treatment.