Hypercalcaemia and Primary hyperparathyroidism in pregnancy
Fareeha Rizvi, Royal London Hospital, Barts Health NHS Trust
We present the case of a 39 year-old lady with primary hyperparathyroidism referred from Lister for further workup at Barts hospital. The corrected calcium at the time of referral was 2.82 and she was largely asymptomatic. She had a background of Coeliac disease, for which she had undergone a recent DEXA scan for this, (which was normal). Was on no regular medications, there was no significant family history and Clinical examination unremarkable.
An Ultrasound of the parathyroids was requested, which showed parathyroid gland enlargement just inferior to the lower pole of the LEFT thyroid lobe measuring up to 15 mm in craniocaudal dimension and approximately 9 x 6 mm in the short axis.
She then underwent a CT neck, which confirmed the presence of a slightly exophytic thyroid nodule in the right lower pole which corresponds to the changes described on the ultrasound. The hypoechoic structure, adjacent to the lower pole of the left lobe of the thyroid was seen on CT and thought to be an anatomically a good location for a parathyroid gland, with no other candidate for parathyroid enlargement seen.
She was referred to the Endocrine Surgical team, to aim for a left lower parathyroidectomy with removal the ipsilateral gland in order to confirm the absence of hyperplasia. However, at the surgical clinic appointment, she reported being 6weeks pregnant, and so a plan to defer her surgery, until later in pregnancy was made.
Our patient then moved to a different town, where she booked her pregnancy and regular follow up with Barts Hospital was unfortunately lost. She was eventually re- referred by her local physicians and was urgently contacted to attend the Barts Endocrine clinic, at which point she was 28 weeks pregnant and was admitted from clinic.
Whilst an in-patient her case was discussed with the local endocrine surgeons, obstetricians and maternal medicine specialists to formulate a plan for the management of her hyperparathyroidism in pregnancy. Her corrected serum calcium remained around 2.9 mmol/L, again, with minimal symptoms related to hypercalcaemia per se.
The obstetric team had multiple concerns, namely the
· Risk of developing pre-eclampsia and arrythmias from the hypercalceamia, which will require close monitoring. If discharged, it was advised that she have twice weekly BP monitoring and urine dipsticks. We will aim for a BP of less than 150/100 mmHg.
· The fetus is at risk of Intra uterine growth restriction and stillbirth – so will require urgent growth scans with dopplers, and the patient should monitor fetal movements.
· Delivery should be under consultant led care at the RLH, with input from neonatology (due to risk of neonatal hypocalceamia).
· If an iatrogenic preterm delivery is planned she will require administration of steroids for fetal lung maturation.
All of the above was discussed with the patient and she wished to proceed to 30-32 weeks of pregnancy, maintaining an oral fluid intake until then, of 4L/day. The aim was to keep the serum Calcium level at <2.8 mmol/L (it was 2.77 on discharge).
The patient managed to maintain an impressive oral fluid intake of around 4-6 Litres/day, but was eventually admitted to the RLH during her 32nd week of pregnancy, under the obstetric and endocrine team, for an elective parathyroidectomy. Her corrected Calcium went from 2.94 (pre operatively) to 2.33 post operatively. She was well post operatively, with only transient symptoms of paraesthesia, related to the fall in the serum calcium.
The histology confirmed a simple parathyroid adenoma, and subsequent serum calcium readings were within the normal range (2.28mmol/L) on discharge.
This was a complex endocrine case, which highlighted how crucial good communication is across various specialities, across two hospital sites. (endocrinology, endocrine surgery, obstetrics and maternal medicine). The patient was continually involved in all decision making, and thus had a favourable and satisfactory outcome.