Severe hypercalcemia and hypercalcemic crisis during pregnancy constitute a clinical problem affecting both mother and child. Treatment involves rehydration and timing of surgery as well as the consideration of a potential postoperative hypoparathyroidism for the mother as well as for the child. Preeclampsia and HELLP-syndrome are potentially life-threatening scenarios in late pregnancy involving severe hypertension and multi-organ failure.

We report a 38-year-old primipara with no previously known hypercalcemia coming to the obstetric department in gestation week 33+1 with signs of preeclampsia (BP 185 mmHg, anemia and low platelets). A caeserian section was planned. A concomitant severe hypercalcemia (3.20 mmol/L) with elevated PTH (13 nmol/L) was noted and a possible upcoming hypercalcemic crisis was feared.

A dilemma occurred as aggressive rehydration and calcium-lowering medication was partially contraindicated due to the preeclampsia and on-going pregnancy. The patient also showed signs of a HELLP-syndrome with rising liver parameters. A subacute caesarian section was performed. An ultrasound revealed a parathyroid adenoma which was removed by a focused procedure. Postoperative magnesium was administrated as preeclampsia prophylaxis and the blood pressure was controlled with vasopressors. The patient recovered and lab parameters normalized including the calcium level. The recovery was uneventful, and the patient had a normal BP and normal calcium levels at follow-up. The child did well without having any signs of hypoparathyroidism. Postoperative gene-analysis was negative for hereditary disease.

Hypercalcemic crisis in combination with preeclampsia and HELLP-syndrome during pregnancy is a rare and serious condition that demands multidisciplinary co-work.