Endocrine Abstracts

19 years-old female was diagnosed with thyrotoxicosis for the first time in 2015; Severe hypothyroidism developed after 1 month thiamazole therapy, therefore medication was stopped and the patient was prescribed L-T4 that resulted in improvement of thyroid function tests. L-T4 was finally withdrawn and TSH returned to normal. Since then TSH was constantly monitored and the levels were normal. In 01/2020, the patient was presented with complains about increased heart rate, emotional lability, hand tremors and oligomenorea. Lab tests revealed overt thyrotoxicosis (TSH – 0.001 mIU/ml); Additional studies, performed to clarify the genesis of thyrotoxicosis, revealed increased levels of Anti-Tg antibodies; Antibodies against TSH receptors were negative; the ultrasound of the thyroid revealed the presence of nodules in the gland, in order to clarify the diagnosis, the patient underwent a radioisotope scan of the thyroid gland, which showed decrease in uptake – 0% – consistent with destructive thyroiditis. The patient was diagnosed with transient thyrotoxicosis due to Hashimoto’s thyroiditis (destructive form), which did not require pathogenic treatment, therefore, only symptomatic treatment was prescribed (beta-blocker and hydration). The studies conducted after 2 months (03/2020) were consistent with hypothyroidism (TSH – 9.5 mIU/ml, FT4 – at the lower limit of normal). She was given levothyroxine (initial dose – 25 mg); as the result thyroid hormone levels returned to normal. Since the patient has diagnosed with autoimmune thyroiditis and is being treated with levothyroxine, on the back of this, there were very frequent episodes of Hashitoxicosis (at least 6 episodes in recent years) for which it is necessary to reduce the dose of thyroxine or stop therapy completely, after which marked hypothyroidism develops soon. The patient feels thyrotoxicosis and hypothyroidism subjectively, and symptoms are disturbing for her. In addition, the patient plans pregnancy. Considering the frequent episodes of Hashi-toxicosis, target level of TSH <2.5 mIU/l according to patient’s pregnancy plans and the patient’s will, a shared decision was made for operative treatment – in favor of total thyroidectomy. The patient was recommended to consult a surgeon to plan total thyroidectomy. In addition, the patient has been diagnosed with polycystic ovary syndrome (hyperandrogemenia, hirsutism, oligomenorea); she is on therapy with combined oral contraceptive pills with positive result. Frequent episodes of Hashi-toxicosis with subsequent development of hypothyroidism has negative effect on reproductive system and ovarian function. So, prompt normalization and stabilization of thyroid function tests after surgery and maintaining TSH below 2.5 mIU/ml is planned for pregnancy.