Endocrine Abstracts

Amiodarone is frequently used in cardiac patients but has side effects which effects the thyroid due to its high iodine content. The use of radioiodine in AIH with low iodine uptake is controversial. In these patients therapeutic choices for refractory cases include either: surgery, antithyroid drugs, or glucocorticosteriods.

What are the treatment choices in elderly patients which can’t be operated on, agranulocytosis is present, or have toxic liver failure after methimazol therapy?

Aim: The aim of study was the evaluation of radioiodine therapy results in AIH patients with low radioactive iodine uptake (RAIU).

Patients and methods: We examined 9 patients with AIH, 1 female (11.1%), and 8 males (88.9%) aged from 63 to 78 years. (x±S.D.: 69.2±5.5 years). The therapy including amiodarone was essential for the underlying heart disorder. Radiotherapy was the necessary medical choice because of: in two cases – agranuloccytosis post antythyroid drugs, additionally in two cases with diabetes mellitus (against glucocorticoid therapy), and five hepatic failure. In all of them, surgical intervention was excluded. The diagnostic procedure included baseline thyroid function test (fT3, fT4 and TSH levels), thyroid autoantibodies (TgAb, TPOAb, TRAb), thyroid ultrasound, thyroid scan, and RAIU. RAIU in all cases was below 10% at 24 h.

Results: Serum values of TSH, TgAb, TPOAb, TRAb were undetectable. Serum fT4, fT3 were as follows: fT4 12.4 to 49 pmol/l (mean: 28.4±13.6); fT3 3.9 to 6.8 pg/ml (mean: 5.7±1.4). Mean thyroidal 5-h and 24-h RAIU values were 5.1±1.0 and 8.2±1.4%, respectively. In every patient, an ablative dose of 131I (22 mCi=814 MBq) was administered.

Conclusion: Iodine therapy can be a useful therapeutic method in every case with low RAIU and in which other treatments (surgery, antytyroid drugs, glucocorticoid) are contraindicated if the dose used is ablative.