Faculty Bibliography

The euthyroid autonomous nodule of the thyroid may escape diagnosis if only the usual criterion of less than 50% suppression of radioactive iodine uptake, (RAIU) after administration of liothyronine sodium is employed. This was the case in four patients who had thyrotoxic response to suppressive therapy, which had been given as a result of the improper conclusion that a nodule was hyperplastic, after the RAIU had fallen. We studied 95 patients with a solitary functioning nodule and found ten euthyroid persons (11 tests) in whom scintiscans showed persistent function in the nodule in spite of suppression of the RAIU by more than 50%. A thyrotropin-releasing hormone test demonstrated lack of thyroid-stimulating hormone responsiveness after administration of liothyronine, proving adequacy of the suppressive dose. Diagnosis of an autonomous nodule should not be excluded unless a scintiscan reveals that its function, in distinction to the rest of the gland, is curtailed by adequate suppression.

Platelet IgG levels, count, and function and easy bruising or bleeding were studied in 25 patients with Graves' disease and 12 with Hashimoto's thyroiditis (normal value for platelet IgG 10.7 +/- 4.5 ng [SD]/10(6) platelets). Eight of 22 patients with Graves' disease and normal platelet counts had elevated platelet IgG averaging 38 +/- 4.0 ng (SEM) (range, 24 to 60). Four of 10 patients with Hashimoto's thyroiditis and normal platelet counts ahd elevated platelet IgG averaging 45 +/- 7.2 ng (range, 27 to 66). Five patients with thrombocytopenia had platelet counts averaging 53000 +/- 12000/microL (SEM) and elevated platelet IgG averaging 154 +/- 40 ng (range, 27 to 300). Twelve of 15 patients with a history of easy bruising or bleeding had elevated platelet IgG compared to five of 22 without easy bruising (p < 0.001). Four of six with elevated platelet IgG had one or more abnormal in-vitro platelet aggregation measurements (particularly with epinephrine) compared to none of six with normal platelet IgG levels (p = 0.03). We conclude that elevated platelet IgG is associated with easy bruising and thrombocytopenia in about half of patients with Graves' disease or Hashimoto's thyroiditis

We assessed the cancer-predictive value of a nonoperative, two-stage prospective selection of solitary, cold, solid thyroid nodules that can be employed by the primary clinician. One hundred eighteen patients completed the protocol, all without adverse effect. The first stage identified for direct surgery 30 patients with a history of exposure to irradiation during youth, age under 20 years, recent growth of a hard nodule or lymphadenopathy, revealing 15 cancers and ten adenomas. In the second stage, the remaining 83 patients were given liothyronine for three months. Twenty-six nodules were excised because they failed to shrink 50% in diameter, disclosing five cancers and 19 adenomas. There were no cancers among 14 nodules excised for other reasons. Selection for surgery on the basis of clinical evaluation and risk factors alone can identify most of the cancers and lack of response to suppression a few more.