Management of PTHrP-mediated hypercalcaemia presenting with pseudoangiomatous stromal hyperplasia (PASH) in pregnancy

Hypercalcaemia in pregnancy presents with altered mental status, constipation, fatigue and nausea. Hypercalcaemia mediated by parathyroid hormone-related protein (PTHrP) secondary to benign breast findings in pregnancy is extremely rare. Since this first documented case in 1988 by Van Heerden et al, there have been three other patients diagnosed with this condition. It has an unknown prevalence and incidence in pregnancy. This case series describes the case reports of four patients with hypercalcaemia mediated by PTHrP secondary to mammary hyperplasia in the setting of pregnancy. All four patients presented with symptoms of hypercalcaemia and were treated with medical management before undergoing surgical management. This case report and review of similar cases was written to establish an algorithm that healthcare workers can use to help direct conversations among the multidisciplinary team that these patients require.