Endocrine Abstracts

Inappropriately low circulating PTH levels following thyroid surgery, is the most common cause of iatrogenic hypocalcaemia. Standard treatment of hypoparathyroidism has comprised vitamin D analogue and calcium supplementation. However some patients remain hypocalcaemic despite use of maximal titrated and tolerated therapy. Teriparatide is recombinant formulation of endogenous PTH, containing 34 amino acid sequence which is identical to the N-terminal portion of this hormone. We report a case of severe hypocalcaemia secondary to hypoparathyroidism treated successfully with teriparatide. A 65 year old female was admitted to King’s College Hospital in September 2016 with right upper limb weakness and numbness. She reported nausea, vomiting and diarrhoea. Her past medical history included total thyroidectomy for goitre with subsequent hypothyroidism and iatrogenic hypoparathyroidism. Medications included intramuscular ergocalceferol 600 000 units monthly, calcit 2 gm bd and alfacalcidol 9 mcg total. Biochemistry revealed a corrected calcium 1.67 mmol/l and magnesium 0.69 mmol/l. ECG demonstrated sinus rhythm with a normal QTc interval. She received intravenous calcium infusions with significant symptomatic improvement. Over the course of the subsequent 18 months, despite escalating doses of calcium and vitamin D supplementation, she presented to hospital trusts on multiple occasions with recurrent, symptomatic, severe hypocalcaemia. Requirements escalated to weekly IV calcium infusions. An individual funding request (IFR) was submitted for teriparatide which was initiated in March 2018. Serum calcium normalised 7 weeks after drug initiation in conjunction with alfacalcidol 4 mcg morning and 3 mcg evening with cholecalciferol 6400 units once daily. Since commencing teriparatide, administration of intravenous calcium has not been required.

Conclusion: Teriparatide therapy is not routinely recommended for the management of hypocalcaemia secondary to hypoparathyroidism but should be considered for cases resistant to high dose calcium and vitamin D supplementation. Avoidance of frequent hospital admissions is both cost effective and improves patient quality of life.