Endocrine Abstracts

A 25 year old lady initially presented with symptoms of palpitation, irregular menses and unintentional weight loss. She was a non-smoker with no current pregnancy plans or family history of thyroid disease. On examination, she was tachycardic and had a moderate diffuse goitre but no signs of thyroid ophthalmopathy. She was biochemically hyperthyroid (TSH <0.01 mIU/l, fT4 30.0 pmol/l, fT3 >30.7 pmol/l). Carbimazole 30 mg daily was started for likely Graves’ disease, after standard advice on agranulocytosis and rash and the need for contraception. Definitive therapy with radioactive iodine and surgery were discussed and patient information leaflets provided. A clinic review was booked for her decision on definitive therapy and the TSH receptor antibody result. However, she re-presented in ED 4 weeks later with a 5-day history of sore throat, fever and rash. On examination, she was tachycardic and had a widespread erythematous rash. An urgent FBC showed new and profound neutropaenia (0.12x10⁹/l). TFTs showed ongoing hyperthyroidism (TSH <0.01 mIU/l, T4 15.0 pmol/l, T3 6.9 pmol/l). Her TSH receptor antibodies were elevated at 80 IU/l. She was diagnosed with carbimazole-induced agranulocytosis and rash and underlying Graves’ disease. Carbimazole was stopped immediately. Propranolol was increased from 40 to 80 mg twice daily. An urgent clinic review was booked for consideration of definitive treatment. In clinic 1 week later, her palpitations had improved. TFTs however showed worsened hyperthyroidism (TSH <0.01 mIU/l, fT4 33.8 pmol/l, fT3 >30.7 pmol/l). Her neutrophil count had improved (0.58 x10⁹/l). She was counselled about urgent definitive therapy with either radioactive iodine or surgery. She opted for radioactive iodine but did not attend the appointment. After repeatedly changing her mind about radioactive iodine, she eventually declined to proceed. When she came to clinic 6 weeks later, her TFTs showed ongoing hyperthyroidism (TSH <0.01 mIU/l, fT4 30.0 pmol/l, fT3 >30.7 pmol/l). A semi-urgent total thyroidectomy was recommended. She received pre-operative preparation with potassium iodate 65 mg twice daily for 2 weeks. She then underwent a total thyroidectomy. There were no intraoperative complications. Post-operatively, her calcium and PTH levels remained within the normal range but she developed voice hoarseness. Fibreoptic nasendoscopy showed no evidence of vocal cord palsy. The voice hoarseness resolved promptly. Histology showed moderate diffuse hyperplasia, consistent with partially-treated Graves’ disease and no evidence of neoplasia. Euthyroidism was restored after starting lifelong levothyroxine replacement post-operatively.