Modified-release recombinant human TSH (MRrhTSH) augments the effect of (131)I therapy in benign multinodular goiter: results from a multicenter international, randomized, placebo-controlled study.

BACKGROUND: Recombinant human TSH (rhTSH) can be used to enhance (131)I therapy for shrinkage of multinodular goiter (MG). OBJECTIVE, DESIGN, AND SETTING: The objective of the study was to compare the efficacy and safety of 0.01 and 0.03 mg modified-release (MR) rhTSH as an adjuvant to (131)I therapy, vs. (131)I alone, in a randomized, placebo-controlled, international, multicenter study. PATIENTS AND INTERVENTION: Ninety-five patients (57.2 ± 9.6 yr old, 85% females, 83% Caucasians) with MG (median size 96.0, range 31.9-242.2 ml) were randomized to receive placebo (group A, n = 32), MRrhTSH 0.01 mg (group B, n = 30), or MRrhTSH 0.03 mg (group C, n = 33) 24 h before a calculated activity of (131)I. MAIN OUTCOME MEASURES: The primary end point was a change in thyroid volume (by computerized tomography scan, at 6 months). Secondary end points were the smallest cross-sectional area of the trachea; thyroid function tests; Thyroid Quality of Life Questionnaire; electrocardiogram; and hyperthyroid symptom scale. RESULTS: Thyroid volume decreased significantly in all groups. The reduction was comparable in groups A and B (23.1 ± 8.8 and 23.3 ± 16.5%, respectively; P = 0.95). In group C, the reduction (32.9 ± 20.7%) was more pronounced than in groups A (P = 0.03) and B. The smallest cross-sectional area of the trachea increased in all groups: 3.8 ± 2.9% in A, 4.8 ± 3.3% in B, and 10.2 ± 33.2% in C, with no significant difference among the groups. Goiter-related symptoms were effectively reduced and there were no major safety concerns. CONCLUSION: In this dose-selection study, 0.03 mg MRrhTSH was the most efficacious dose as an adjuvant to (131)I therapy of MG. It was well tolerated and significantly augmented the effect of (131)I therapy in the short term. Larger studies with long-term follow-up are warranted.

Successful treatment of massive acute thyroid hormone poisoning with iopanoic acid.

We report a toddler with massive thyroid hormone poisoning in whom the addition of iopanoic acid to the treatment regimen (propylthiouracil and propranolol) resulted in a dramatic clinical and biochemical improvement. Iopanoic acid is a safe and effective drug in the treatment of massive thyroid hormone poisoning in children.

Thyroid gland function and pituitary TSH reserve in patients with cystic fibrosis.

In view of the reported enhanced sensitivity to iodide-induced hypothyroidism in patients with cystic fibrosis, studies were carried out to determine the possible mechanism of this abnormality. The intrathyroid organification of iodide, as assessed by the iodide-perchlorate discharge test, was normal in patients with cystic fibrosis, strongly suggesting that an organification defect was not present. The serum TSH response to TRH was not significantly different from the response in normal children and adolescents. Serum T4 concentration was normal whereas that of T3 was decreased in patients with cystic fibrosis, strongly suggesting decreased peripheral conversion of T4 to T3, as commonly occurs in nonthyroid illness. Our findings do not delineate the mechanism whereby patients with cystic fibrosis develop iodide-induced hypothyroidism.