Endocrine Abstracts

A 25-year-old pregnant lady presented to the accident and emergency department at 16 weeks gestation with intractable vomiting, weight loss and lethargy. She reported a 2 months history of hyperemesis gravidarum managed in the community prior to admission.

She had no past medical history and her only medication was of a Polish antenatal vitamin containing 400 IU of Vitamin D (D2). Her blood biochemistry revealed a markedly raised corrected calcium at 3.57 mmol/l (2.15–2.55), inappropriately ↑PTH at 17.6 pmol/l (1.6–6.9), ↓Phosphate 0.7 mmol/l (0.87–1.45), ↑Vitamin D 140 nmol/l (50–80). Fractional excretion of Calcium on a 24 h urine collection was 0.03 (>0.01) excluding familial hypocalciuric hypercalcaemia.

She was treated with intravenous normal saline (4 l/day) for 4 days but unfortunately her calcium only marginally decreased to 3.17 nmol/l. She was reviewed by the obstetricians and no foetal complications were detected. An ultrasound of her parathyroid glands revealed a right inferior pole parathyroid adenoma 1.5 by 1 cm. At 20 weeks gestation, she was referred to a specialist endocrine surgeon and underwent a minimally invasive parathyroidectomy with rapid intraoperative PTH measurement. The operation was successful with a postoperative PTH of 3 pmol/l and cCa 2.23 with no complications. Given that she has presented with hyperparathyroidism at such a young age, she will clearly require screening for MEN-1.

The prevalence of primary hyperparathyroidism in the general population is 0.15% and a quarter of these cases occur in women of childbearing age, however there are only an estimated 200 cases reported in the literature thus far. Symptomatic hyperparathyroidism in pregnancy is ideally managed with surgery in the second trimester. Regardless of whether the hyperparathyroidism is managed medically or surgically, the pregnancy is regarded as high risk and a high degree of vigilance is indicated with a clear multidisciplinary approach. Had the ultrasound scan been negative (sensitivity<50%) in this lady with no clear surgical target, the management may have been even more complicated, especially since sestamibi scanning is contraindicated in pregnancy.