Endocrine Abstracts

A 24-year-old lady was diagnosed with thyrotoxicosis following an emergency admission, with a normal laparotomy, for right iliac fosa pain. She was commenced on carbimazole. After self discontinuation of carbimazole she was re-referred, by her GP, with poorly controlled thyrotoxicosis and typical features of weight loss, anxiety, oligomenorrhoea and tremor. Her FT4 on re referral was 60 pmol/l, suppressed TSH and raised TPO antibodies. She then had an unplanned pregnancy which resulted in a termination.

A total thyroidectomy was performed due to aggressiveness of the disease. Post-operatively she developed profound and resistant hypocalcaemia and hypomagnesaemia requiring management with pharmacological doses of vitamin D, calcium and magnesium supplements indicating that she had developed permanent hypoparathyroidism. She was given replacement doses of thyroxine, 150 mcg daily which initially seemed adequate. During the course of controlling the post-operative hypocalcaemia and hypothyroidism she became pregnant again which was unplanned.

The pregnancy was complicated by worsening biochemical hypothyroidism in spite of reported compliance with medication and increasing doses of thyroxine and triiodothyronine. The calcium levels remained stable. Throughout the pregnancy her TSH levels were >50 miu/l. She finally needed a thyroxine dose of 600 mcg and triiodothyronine 20 mcg twice daily to maintain a TSH <5.0 miu/l.

Foetal growth was normal on scan but dopplers showed a high resistance at 36 weeks. She was admitted for observation and induced at 38 weeks. TRAB antibodies during the 3rd trimester were raised. There was no evidence of foetal tachycardia and the baby’s thyroid function was normal after delivery.

Since delivery the baby continues to develop normally.

This case highlights the importance of educating patients in relation to the risk of thyroid disease in pregnancy.