Treatment of severe life threatening hypocalcemia with recombinant human teriparatide in patients with postoperative hypoparathyroidism - a case series.

Introduction: Hypocalcaemia is a common postoperative complication, both after the resection of parathyroid adenoma associated with primary hyperparathyroidism and after total thyroidectomy due to thyroid cancer or nodular goitre. For a few years, in patients with postoperative hypoparathyroidism and severe hypocalcaemia, who cannot discontinue intravenous calcium preparations even with the use of high vitamin D doses, attempts have been made to add recombinant human parathormone (rhPTH) to the treatment schedule. In this work, for the first time in Poland, we demonstrate the potential use of teriparatide for the treatment of severe hypocalcaemia based on three different cases of postoperative hypoparathyroidism.

Material And Methods: Case 1. Female (52) with postoperative hypoparathyroidism, after total thyroidectomy and the removal of lower left parathyroid gland due to hyperparathyroidism, several weeks after the surgery still required intravenous calcium infusions because of tetany symptoms. Just one month of teriparatide treatment at 20 μg/0.08 mL given in daily subcutaneous injections proved sufficient to control calcium levels with oral calcium and vitamin D preparations during the next few days until total resolution of hypocalcaemia symptoms and the achievement and maintenance of laboratory normocalcaemia in the following weeks.

Case 2: Female (33) with hypoparathyroidism following total thyroidectomy in 1996 because of papillary thyroid cancer, with congenital tubulopathy associated with renal loss of calcium and magnesium, and the symptoms of tetany recurring since the day of surgery, requiring intravenous calcium administration every 2-3 days. Currently, the patient has been hospitalised because of venous port infection, the only venous access, which made intravenous therapy impossible. Because of the life-threatening condition of the patient, bridging teriparatide treatment was prepared (20 μg/0.08 mL). Complete resolution of clinical symptoms of hypocalcaemia was obtained with teriparatide doses given every 8-12 hours, which made dose reduction possible. Case 3. Female (52) after major oncological surgery because of laryngopharyngeal and cervical oesophageal cancer with the removal of parathyroid glands, fed through PEG, was admitted to hospital with the symptoms of tetany. Despite treatment intensification, the patient experienced a hypocalcaemic crisis during hospitalisation. Teriparatide treatment at 2 × 20 μg/day resulted in the resolution of tetany symptoms, with gradual normalisation of calcium-phosphate balance parameters during the following days.

Conclusions: Based on the analysis of these cases, the conclusion was drawn that the use of recombinant human teriparatide allows for the control of severe hypocalcaemia requiring intravenous infusions of calcium in patients with postoperative hypoparathyroidism. (Endokrynol Pol 2016; 67 (4): 403-412).