INCIDENCE OF DYSTHYROIDISM DURING INTERFERON THERAPY IN CHRONIC HEPATITIS-C

Seventy-nine patients (40 males, 39 females) were enrolled in a prospe ctive study of lymphoblastoid interferon-alpha (IFN), 3-5 MU three tim es weekly. They were randomly assigned to receive either 12 months of IFN therapy, or to 6 months of observation followed by 6 months of IFN therapy. The thyroid functional and immunological status was checked every other month during and after treatment. Before treatment, antith yroid antibodies were found in 6 patients (7.5%). Two were hypothyroid and were excluded from the study before starting IFN therapy. Seventy -seven patients received IFN therapy. Of these, thyroid abnormalities appeared in 6 (7.5%). Hyperthyroidism was observed in 3 patients. Two recovered within a few months, but 1 developed subsequent hypothyroidi sm. Hypothyroidism was observed in 2 patients. TSH blood values were p ersistently abnormal, but thyroid antibody levels remained increased a nd fluctuating. Thyroid function usually recovered within a few months ; but 2 patients required hormonal therapy and 1 was treated with carb imazole. In 1 patient, a small thyroid papillary carcinoma was observe d, but no evidence of relationship with the liver disease or with IFN therapy was found. In a patient with chronic hepatitis C, systematic t hyroid assessment should be performed before initiating IFN therapy, i ncluding clinical examination, and measurement of TSH and anti-thyrope roxidase antibodies (TPO Ab). During treatment, a TSH assay every othe r month appears to be necessary and sufficient.