Recurrent Graves’ hyperthyroidism after prolonged radioiodine-induced hypothyroidism

Background: Radioactive iodine (RAI) is the most cost effective therapy for Graves’ disease (GD). Patients with GD who have become hypothyroid after therapeutic RAI, rarely develop recurrence of disease. Herein we describe a case of recurrence of thyrotoxicosis after 2 years of hypothyroidism. Methods: We present the clinical features, laboratory findings, imaging and management of an unusual case of recurrent hyperthyroidism. Results: A 48-year-old male presented to the emergency room with a 2-day history of palpitation, chest discomfort and 30 pounds of weight loss. Examination was remarkable for rapid and irregular pulse, diffuse thyromegaly and brisk deep tendon reflexes but no eye changes or tremors. Laboratory tests showed thyroid-stimulating hormone (TSH) of <0.004 (0.3–5.6 mIU/ml), free thyroxine (FT4) 4.96 (0.9–1.8 ng/dl), free triiodothyronine (FT3) >20 (1.8–4.7 pg/ml), total thyroxine >800 (80–200 ng/dl). Electrocardiogram showed atrial fibrillation with rapid ventricular response. RAI uptake and scan showed a homogenous gland with 54% uptake in 6 h and 45% in 24 h. He was treated with propranolol and propylthiouracil with some clinical improvement. He subsequently underwent RAI therapy and developed hypothyroidism after 8 weeks. Hypothyroidism was treated with levothyroxine. At 2 years after RAI ablation, he again developed symptoms of hyperthyroidism and had suppressed TSH. The levothyroxine dose was stopped, 3 weeks after discontinuing levothyroxine, he remained hyperthyroid with TSH of 0.008 and FT4 of 1.62 and FT3 of 4.8. RAI uptake demonstrated 17% uptake at 24 h. Conclusion: Recurrent hyperthyroidism in GD is uncommon after development of post-ablative hypothyroidism. Our case illustrates the need for continued surveillance.

Long-Term Follow-Up of a Child with Autoimmune Thyroiditis and Recurrent Hyperthyroidism in the Absence of TSH Receptor Antibodies

Hashitoxicosis is an initial, transient, hyperthyroid phase that rarely affects patients with Hashimoto thyroiditis. We present here an unusual case of a child with Hashimoto thyroiditis and recurrent hyperthyroidism. A 4 yr 6/12 old male was diagnosed by us with autoimmune subclinical hypothyroidism (normal free T4, slightly elevated TSH, and elevated TG antibody titer). Two years and 6/12 later he experienced increased appetite and poor weight gain; a laboratory evaluation revealed suppressed TSH, elevated free T4, and normal TSI titer. In addition, an I123thyroid uptake was borderline-low. A month later, the free T4 had normalized. After remaining asymptomatic for 3 years, the patient presented again with increased appetite, and he was found with low TSH and high free T4. Within the following 3 months, his free T4 and TSH normalized. At his most recent evaluation, his TSH was normal and the free T4 was borderline-high; the TG antibody titer was still elevated and the TSI titer was negative. To our knowledge, this is the first patient reported with Hashimoto thyroiditis and recurrent hyperthyroidism. This case exemplifies the variability of the manifestations and natural history of Hashimoto thyroiditis and supports the need for a long-term evaluation of patients with autoimmune thyroid disease.

Surgical treatment of Graves’ disease: Subtotal thyroidectomy might still be the preferred option

Objective. The aim of this prospective study was to report our results after thyroidectomy for Graves’ disease. In addition, the relationship between the thyroid remnant and postoperative thyroid function was studied. Material and methods. Forty-nine consecutive patients were operated on for Graves’ disease. The indications for surgery were persistent or recurrent hyperthyroidism after medical treatment in 34 patients (69.4%), mechanical symptoms due to a large goiter in 7 (14.3%), increased ophthalmopathy in 7 (14.3%), and allergy to antithyroid medications in 1 patient (2.0%). Total thyroidectomy (TT) was performed in 28 and subtotal thyroidectomy (STT) in 21 patients. Followup lasted 24 to 70 months. Results. There was no statistically significant difference in the rate of postoperative complications comparing TT and STT. The patients who underwent TT had no recurrence during a mean follow-up of 47 months. After STT, with the mean weight of the thyroid remnant 3.0±1.0 g, there was no relapse of Graves’ disease during a mean follow-up of 52 months. After STT, postoperative hypothyroidism developed in 14 patients (66.7%); 7 patients (33.3%) remained euthyroid during follow-up. Comparison of the euthyroid patients and the hypothyroid patients revealed no difference in the weight of the remnant (3.3 g vs. 2.8 g), but a statistically significant difference occurred in the weight of the resected gland (61.0 g vs. 94.4 g, P=0.026) and in the proportion of the remnant (5.6% vs. 3.3%, P=0.030). Conclusions. Both TT and STT are safe procedures regarding postoperative complication rate. STT with the thyroid remnant of about 3 g allows to permanently cure hyperthyroidism ensuring the euthyroid state in a significant proportion of patients. Postoperative thyroid function after STT is best predicted by the proportion of the remnant.