Endocrine Abstracts

Beckgrounds and aims: The most common cause of hypoparathyroidism is postoperative, i.e., after thyroid, parathyroid, or radical neck surgery due to neoplasms, and is most often transient, whether continuous or even intermittent. The incidence of permanent hypoparathyroidism ranges from 0.8 to 3.0% in patients after total thyroidectomy. In this case report, we will present a patient with a severe form of postoperative hypoparathyroidism refractory to standard treatment regimens.

Methods: A 49-year-old patient underwent total thyroidectomy due to recurrent hyperthyroidism and diffuse goiter. Postoperatively, she received levothyroxine, cholecalciferol, and calcium carbonate. Two months after the procedure, the patient complained of tingling in her hands, feet, and face and spasms of the esophagus. Since then, lower values have been constantly observed in the findings of total and ionized Ca with immeasurably low PTH. The dose of drugs was gradually increased (cholecalciferol: 25 000 IU once a week; calcitriol: up to 4.5 mg; calcium carbonate: up to 6 g; magnesium citrate: 300–400 mg per day) with frequent applications of calcium gluconate infusion, without improvement. Since rhPTH (l-84) is not available in our country, we started with subcutaneous administration of teriparatide with a gradual increase in the dose up to 3x20 mg per day, but without improvement. After reviewing the literature, we decided to use teriparatide via an insulin pump.

Results: After the introduction of the catheter-less pump, the serum Ca values quickly normalized, and during the following 3 months, they were maintained at reference values with a stable dose of teriparatide (24 mg/24 h). On January 5 2023, the patient switched to a catheter pump, and since then, large oscillations of serum Ca have been monitored again with symptoms of hypocalcemia and the need for constant correction of the teriparatide dose. On April 28 2023, she switches again to a catheter-less pump with stabilization of the general condition and the dose of teriparatide (18 mg/24 h).

Conclusions: Although chronic postoperative hypoparathyroidism rarely occurs, in most cases it is easily resolved with the use of vitamin D and calcium supplements. In a small number of patients, it is necessary to apply replacement therapy with a parathormone analogue. In our case, the patient stabilized only after continuous use of teriparatide via an insulin pump.