Endocrine Abstracts

Section 1: Case history: A 39-year-old Asian lady at 18 weeks of gestation, after in vitro fertilisation pregnancy, was found to have an adjusted calcium level of 3.08 (range 2.20-2.60 mmol/l) on routine blood tests. She was asymptomatic. Her Parathyroid hormone (PTH) was 14.1 (1.1-6.9pmol/l) and 25 hydroxy vitamin D 16 (15-174 nmol/l). She had insulin treated diabetes following an episode of pancreatitis for which no cause was identified. She was treated as an inpatient with intravenous fluids and furosemide which improved the calcium to 2.67; however, calcium would increase to >3 after cessation of IV fluids.

Section 2: Investigations: 24-hour urinary calcium and creatinine excretion results are inconclusive in pregnancy. A genetic analysis Hyperparathyroidism gene panel excluded Familial hypocalciuric hypercalcaemia (FHH). USS parathyroid did not identify an adenoma. Following multi-disciplinary team discussion, a CT neck scan was performed, and it did not localise an adenoma.

Section 3: Results and treatment: A clinical diagnosis of primary hyperparathyroidism (PHPT) was then made. Patient was reviewed by Obstetricians and Endocrine surgeons. In view of persistent hypercalcaemia, she was initiated on Cinacalcet 30mg twice daily which maintained her calcium level between 2.69 and 3.21. She had a parathyroidectomy at 31 weeks of gestation where a right inferior parathyroid adenoma was removed. Post-operative calcium level was 2.58 and PTH 3. She had a caesarean section at 36 weeks and successfully delivered a baby girl. The new-born”s calcium and PTH were normal, however; phosphate was high. Phosphate levels were monitored and normalised after 2 weeks. Cinacalcet has been reported to be associated with neonatal hyperphosphatemia.

Section 4: Conclusions and points for discussion: Hypercalcaemia in pregnancy is uncommon but has potential maternal and foetal complications, making a compelling argument for routine antenatal and calcium screening. The use of high-dose Cinacalcet in pregnancy as in this case, can help to manage resistant hypercalcaemia. This case highlights the beneficial role of joint management and timely surgical interventions for severe primary hyperparathyroidism in pregnancy to ensure the best possible maternal and foetal outcomes.