ABSTRACT Title: Familial Hypocalciuric Hypercalcaemia in Pregnancy Introduction: Familial hypocalciuric hypercalcaemia (FHH), benign outside of gestation, becomes potentially life threating for a neonate born to an affected mother as it can cause neonatal hypocalcaemia, seizures and tetany1. Thus, it is an important condition to recognise in pregnancy. Case: A 26 year old, Gravida 3, Para2, lady presented for review at 11 weeks gestation, with asymptomatic hypercalcaemia of 2.91mmol/L (2.13-2.63) and parathyroid hormone (PTH) level of 3.6 pmol/L (1.0-6.8). She had a background history of FHH, confirmed by genetic testing and a family history of 8 affected members. During her first pregnancy her calcium levels ranged from 2.9 - 3.09 mmol/L with PTH between 1.1- 2.3pmol/L. She underwent emergency caesarean section due to failure to progress at 41 weeks gestation. She delivered a healthy boy who was normocalcaemic and unaffected on genetic testing. In her second pregnancy, her calcium ranged from 2.92- 2.97 mmol/L, with PTH 1.1-4pmol/L. She underwent elective caesarean at 39 weeks gestation and delivered a healthy girl, whose calcium was 3.08mmol/L (1.75-2.99). Subsequent genetic testing confirmed her inheritance of FHH. This pregnancy she will undergo monitoring of her calcium levels. Upon delivery, the neonate will undergo calcium monitoring and genetic testing. Discussion: FHH is an autosomal dominant condition caused by inactivating mutations of the calcium sensing receptor2. 50% of foetuses will be affected and have asymptomatic hypercalcaemia. Unaffected foetuses risk foetal parathyroid suppression from maternal hypercalcaemia, with complications including seizures described1. References: 1. 1.Cooper, Mark. (2011). Disorders
of calcium metabolism and parathyroid disease.Best Pract Res Clin
Endocrinol Metab. 25(6):975-83. |