Use of teriparatide for treatment of a 3-year-old child with an activating calcium sensing receptor mutation

Calcium sensing receptor (CaSR) variants are a rare cause of congenital hypoparathyroidism. Current standard treatment consists of calcitriol and calcium supplements, but this regimen increases the risk of kidney complications due to hypercalciuria. Here we present the case of a toddler with an activating CaSR mutation and severe complications of calcium and calcitriol treatment, who exhibited significant clinical improvement after initiation of teriparatide, an injectable PTH analogue. Studies of teriparatide use in children have shown that it is well tolerated and efficacious for the long-term management of hypoparathyroidism. However, few studies have documented its use in toddlers.