An 18-year-old female presented to acute services with polydipsia and lower back pain. Routine blood tests revealed hypercalcaemia 3.67 mmol/l with significantly raised parathyroid hormone levels 2986 ng/l (1065), alkaline phosphatase (ALP) 3330 IU/l (30130), and low vitamin D 10.3 nmol/l (50220). A CT scan revealed a 3.5 cm parathyroid adenoma and very osteopenic bones with multiple lucencies in keeping with primary hyperparathyoidism. The parathyroid subtraction scan Tc/MIBI reported a large area of activity in the lower left lobe of the thyroid gland corresponding with the CT findings.
The patient subsequently underwent parathyroidectomy for a 3.5 cm parathyroid adenoma weighing 15 g with histology showing chief cell adenoma. The patients calcium dropped within 24 h post surgery and she became symptomatic with Chvosteks sign positive, carpopedal spasms, perioral numbness, and paraesthesia. Calcium was1.87 mmol/l and despite treatment dropped to 1.63 mmol/l, phosphate 0.6 mmol/l, and magnesium 0.5 mmol/l.
She required prolonged high dose i.v. calcium and magnesium infusions with oral phosphate, high doses of oral calcium and activated vitamin D supplementation for hungry bone syndrome which continued for over a month. This case highlights a particularly severe case of primary hyperparathyroidism with rarely seen radiological features and development of rare post-operative complications. Despite acknowledgement of the risk, development of hungry bone syndrome was not avoided and the patient spent a significant number of days as an inpatient. This case describes in detail the large amounts of calcium and magnesium replacement regimes required (including i.v. regimes for over a month) that have not previously been documented in literature. It also discusses the potential risk factors for development of hungry bone syndrome.