AMYLOID GOITER - RADIOLOGICAL STUDY IN A CASE PRESENTING HYPOTHYROIDISM

We report herein a case of amyloid goiter associated with rheumatoid a rthritis in which hypothyroidism was observed. A SZ-year-old housewife who had suffeed from rheumatoid arthritis for 15 years was referred t o our hospital because of general fatigue. On admission, a large goite r was observed. Laboratory data showed primary hypothyroidism. Renal b iopsy and gastric mucosa biopsy showed amyloid deposition of AA-type, Thyroid biopsy showed massive amyloid involvement. Although the findin gs of iodine-123 scintigraphy, technetium-99m pertechnetate scintigrap hy, computed tomography and magnetic resonance image studies were simi lar to those for goiter associated with chronic thyroiditis, tallium-2 01 chloride scintigraphy gave a differing result, demonstrating absent uptake at 3 hours in this case. Replcement therapy with levothyroxine relieved the symptoms. This case was unusual in that amyloid goiter p resented clinically as hypothyroidism. Absence of tallium-201 chloride uptake at 3 hours may be a diagnostic specificity for amyloid goiter in differentiating its hypothyroidism from that caused by chronic thyr oiditis.