Hashimoto's Thyroiditis in HTLV-I Carriers.

We describe two HTLV-I virus carriers who have biopsy-proven Hashimoto's thyroiditis. The first patient, a 64-year-old female, has had goiter and hypothyroidism since the age of 56. The second patient, a 66-year-old male, developed hyperthyroidism and goiter at the age of 44, but at present he is hypothyroid. Both patients are positive for anti-thyroid antibodies and anti-HTLV-I virus antibody. Findings of the thyroid biopsy specimens were consistent with Hashimoto's thyroiditis. These data suggest that Hashimoto's thyroiditis develops in HTLV-I carriers who have no clinical evidence of HAM/TSP.