A 32-year-old female presented with symptoms of low energy level, weight gain, cold intolerance, increased bowel movements, flaking, and itchy scalp in the year 2014. On examination, she was found to have a palpable goiter. Her family history was significant for thyroid disease affecting her sibling. Neck ultrasound demonstrated diffusely enlarged thyroid with mild heterogeneous echotexture and left hypoechoic solid nodule measuring 0.75 cm []. Thyroid function test (TFT) was within the normal limits (TSH: 3.4 μIU/mL and FT4: 1.1 ng/dL; normal laboratory values of TSH 0.350–4.940 uIU/mL and FT4: 0.7–1.5 ng/dL respectively) however, antithyroid peroxidase (1446.0 IU/ml; reference range 0.0–5.6 IU/ml) and Tg antibodies (95.4 IU/ml; reference range 0.0–4.1 IU/ml) were high. A diagnosis of euthyroid Hashimoto's disease was made, and the patient was followed up on ultrasound and TFT.\nIn the year 2016, the patient presented with irritability and anxiety. Repeat ultrasound showed status quo. However, there was a surge in thyroid antibodies and an increase in TSH levels (7.2 μIU/mL). The clinical impression was consistent with Hashimoto's thyroiditis and the patient was started on low-dose thyroxine, which she tolerated well for 3 years. On yearly follow-up, there was a downtrend in thyroid antibodies, TSH returned to normal range, and findings on ultrasound remained stable.\nIn October 2019, the patient presented with syncopal episode. Evaluation of TFT demonstrated low TSH of 0.003 μIU/mL and raised FT4 of 2.4 ng/dL. The patient was asked to stop thyroxine tablets and to repeat TFTs in 4 weeks. Repeat TSH was <0.002 μIU/mL and FT4 of 2.6 ng/dL. I-123 thyroid uptake and the scan was performed, which demonstrated findings consistent with Graves' disease [] with 24 h uptake of 63.6% (normal range 10%–25%). The patient was subsequently treated with 15.9 mCi of radioiodine (I-131). Follow-up in 6 weeks of radioiodine therapy, the patient was clinically stable.
A 60-year-old lady, presented with tremulousness of hands for 1 month and palpitation with excessive sweating for 3 months. She had a history of weight loss for 6 months, and gradually enlarging neck swelling for 3 years. She was nervous, irritable, and emotionally labile. Her weight was 46 kg, BMI 17, afebrile, pulse rate: 110/min/regular, blood pressure: 140/56 mm of Hg. Her thyroid gland was symmetrically enlarged, firm in consistency, nodular/lobular surface and mildly tender without any bruit. Palms were warm and sweaty with fine tremor in hands. All reflexes were exaggerated. There were no occular manifestations.\nInitial thyroid function tests (TFT) revealed high T3: 3.80 ng/ml (0.80-2.10), T4: 12.40 ug/dl (5.10-12) with a low TSH: 0.20 mU/L (0.70-5). Her TSH receptor antibody (TSAb): 25 U/L (Normal [nl.] <1), anti TPO antibody: 374 IU/ml (nl. <35) and thyroglobulin antibody: 268 IU/ml (nl. <65) were all strongly positive. Complete hemogram and ESR-18 mm/h (nl.-1-25) were normal. Ultrasonogram of thyroid revealed an enlarged gland with hypoechoic parenchyma with fibrous septa.99mTc pertechnetate scan (Tc99m scan) revealed enlarged thyroid gland with diffusely increased uptake of radiocontrast: 17% (nl. 0.4-4%) with some patchy defects in both lower poles. Thyroid FNAC showed sheets of Hurthle cells with abdunce of lymphocytes and sheets of regular follicular cells, indicating HT. She was observed on beta blockers. Repeat TFT, 3 months later showed: T3: 4.20 ng/ml, T4: 14.40 ug/dl, TSH: 0.001 μU. Repeat 99mTc pertechnetate scan was done, which again revealed enlarged thyroid gland with diffusely increased uptake of radiocontrast: 21% (nl. 0.4-4%) with same patchy defects in both lower poles. Antithyroid medication carbimazole was started.