title: Interferon-induced thyroiditis during treatment  of chronic hepatitis C.
abstract: Thyroid function disorders affect between 5% and 15% of patients treated with IFNα and RBV for chronic hepatitis C. Women and patients with thyroid peroxidase antibodies (TPOAb) found before the treatment are at risk of developing the disorders (46.1% vs. 5.4%). The spectrum of IFNα-induced thyroiditis (IIT) includes two groups. Disorders with an autoimmune background are: presence of thyroid autoantibodies without clinical disease, Hashimoto's disease and Graves' disease. The second group comprises diseases caused by the  direct toxic effect of IFNα on the thyroid gland, i.e. destructive thyroiditis and non-autoimmune hypothyroidism. Thyroid diseases are  not an absolute contraindication for IFNα and RBV therapy. In patients diagnosed with thyroid dysfunction, before the antiviral therapy it is necessary to achieve euthyreosis. Thyroid function disorders may occur at any moment of the therapy. The earliest have been observed in the 4th week of treatment, and the latest 12 months after its termination. During the therapy, in order to diagnose IIT early, it is recommended to determine TSH level every 2-3 months depending on the presence of TPOAb before the treatment. The diagnosis and treatment of thyroid function disorders should be conducted in co-operation with an endocrinologist.
authors.affiliation: Department of Infectious Diseases and Hepatology, L. Rydygier Collegium Medicum in Bydgoszcz, ul. Św. Floriana 12, Bydgoszcz, Poland. d.kozielewicz@wsoz.pl
authors.forename: Dorota
authors.initials: D
authors.lastname: Kozielewicz
authors.forename: Waldemar
authors.initials: W
authors.lastname: Halota
mesh_terms: D000367:Age Factors; D000465:Algorithms; D013956:Antithyroid Agents / Q000627:therapeutic use; D000998:Antiviral Agents / Q000009:adverse effects*; D001323:Autoantibodies / Q000187:drug effects / Q000276:immunology; D003937:Diagnosis, Differential; D004347:Drug Interactions; D005260:Female; D006111:Graves Disease / Q000139:chemically induced* / Q000188:drug therapy / Q000276:immunology; D050031:Hashimoto Disease / Q000139:chemically induced* / Q000188:drug therapy / Q000276:immunology; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; D006801:Humans; D016898:Interferon-alpha / Q000009:adverse effects*; D008297:Male; D012254:Ribavirin / Q000009:adverse effects; D012307:Risk Factors; D012737:Sex Factors; D013961:Thyroid Gland / Q000187:drug effects / Q000276:immunology; D013966:Thyroiditis / Q000139:chemically induced* / Q000188:drug therapy / Q000276:immunology
chemical_list: D013956:Antithyroid Agents; D000998:Antiviral Agents; D001323:Autoantibodies; D016898:Interferon-alpha; D012254:Ribavirin