Endocrine Abstracts

Case history: 36 years old, 14 weeks pregnant lady was referred to endocrinology department by GP urgently with corrected Calcium CCa of 2.97 mmol/l and normal parathyroid hormone (PTH). Her symptoms were urinary frequency and nausea. She had 3 previous miscarriages and 2 normal births. She was on folic acid and vitamin D supplements. There was family history of type 2 diabetes and B12 deficiency. Her 6 family members had normal calcium levels.

Investigations: She had high CCa (2.64–2.97 mmol/l) with normal PTH (3.2–5.2 pmol/l) and low phosphate (0.66–0.93 mmol/l). Her vitamin D, renal function and electrolytes including Mg were normal. Her urinary calcium was 1.24 mmol/l in 24 hours.

Results and treatment: Calcium Creatinine Clearance Ratio of 0.0044 was in favour of Familial Hypocalciuric Hypercalcemia but on other hand negative family history made it difficult to diagnose without further investigation. She had her genetic screening for FHH and her case was discussed with genetic lab to prioritise her test and get results in 1–2 weeks (usually takes 8 weeks). Nuclear medicine team at Oxford advised not to do SETSTAMIBI in pregnancy rather consider MRI scan. Opinion was sought from endocrinologists at Hammersmith Hospital about starting her on cinacalcet in order to reduce hypercalcemia related risk in pregnancy and decision was made not to give it as there was no outcome study on its effect in pregnancy. She was seen by ENT, Obstetrician and obstetric anaesthetist so she could have timely parathyroidectomy in case of negative genetic tests. Her genetic screening was heterozygous positive for CASR which gave her a diagnosis of FHH type 1. She was monitored during rest of her pregnancy which remained uneventful. She delivered normally in May 18 and her daughter’s calcium levels post birth remained normal at 2.4 mmol/l. Patient was continually involved in decision making throughout the management of her hypercalcemia in pregnancy.

Conclusions and points for discussion: Hypercalcaemia during pregnancy is not very common and can result in foetal morbidity and miscarriages. If it is due to primary hyperparathyroidism, guidelines suggest parathyroidectomy if CCa is >2.75 mmol/l which is considerably lower than usual cut off of 3 mmol/l in non-pregnant patients. If surgery is needed the best time is the second trimester as general anaesthesia is safer. When a pregnant patient is diagnosed with hypercalcaemia all the efforts should be done to make the right diagnosis as quickly as possible and plan the management properly.