Thyroid evaluation in patients with hepatitis C infection: correlation to CTLA-4 gene polymorphisms

Abstract

Hepatitis caused by virus C (HCV) correlates to thyroid diseases not only because of interferon-alpha (IFNa) treatment, but also due to common association to thyroid autoimmunity. Finding elevated incidence of thyroid peroxidase antibodies in patients with HCV denotes a genetic susceptibility to autoimmune disorder. CTLA-4 gene is enrolled in preservation of immune tolerance and polymorphisms in this gene are known to be associated to thyroid autoimmune disease, especially Graves’ disease. Thyrotoxicosis related to IFNa has misdiagnosis between destructive thyrotoxicosis and Graves’ disease. Color-doppler ultrasonography might help in distinguish both and therefore start the right treatment. Considering CTLA-4 polymorphisms as genetic markers of thyroid disease in HCV patients, this project aims to characterize prospectively clinical aspects of thyroid disorders in patients infected with HCV before, during and after IFNa treatment associated or not to ribavirin and correlate the presence of thyroid disorder in these patients to CTLA-4 polymorphisms. (AU)