Transient neonatal hypoparathyroidism in two siblings unmasking maternal normocalcemic hyperparathyroidism

Abstract

Hypoparathyroidism is one of the recognized causes of late-onset neonatal hypocalcemia. Maternal hypercalcemic hyperparathyroidism has been shown to suppress fetal parathyroid glands, causing transient neonatal hypoparathyroidism. We report two siblings (6 years apart) with transient hypoparathyroidism presented with hypocalcemic seizures during the first 2 weeks of life. Subsequent investigation revealed an unrecognized normocalcemic hyperparathyroidism with nephrocalcinosis in the mother. Maternal hyperparathyroidism was caused by two parathyroid adenomas. In conclusion, our report highlights the importance of careful evaluation of neonatal hypoparathyroidism in uncovering an unrecognized, asymptomatic hyperparathyroidism in the mother.

Unusual Presentation of Primary Hyperparathyroidism: A Rare Case Report

“…Neonates usually present with poor feeding, hypotonia, stridor, and irritability and the most striking one, are the convulsions. Cardiac involvement is lethal which may manifest as tachycardia, heart failure, prolonged QT interval, or decreased contractility 7 Hypocalcemic seizures in neonates usually are of late onset, 8 contrary to which our case presented with early onset convulsions. Neonatal convulsions not controlled by conventional anticonvulsants should raise the possibility of a metabolic cause -namely, hypocalcemia secondary to maternal primary hyperparathyroidism.…”

Neonatal Seizure as a Manifestation of Unrecognized Maternal Hyperparathyroidism

“…Two siblings with transient hypoparathyroidism presenting with hypocalcemic seizures during the first 2 weeks of life were reported previously. In these patients, subsequent investigation had revealed an unrecognized normocalcemic hyperparathyroidism with nephrocalcinosis in the mother; the maternal hyperparathyroidism was found to be caused by two parathyroid adenomas (6). Most infants with neonatal hypocalcemia due to maternal hyperparathyroidism require short-term Ca supplementation for 3 to 5 months, at which time the hypoparathyroidism resolves (3,4).…”

Successful Conservative Management of Primary Hyperparathyroidism Diagnosed During Pregnancy

“…Maternal PHP causes suppression of fetal parathyroid glands secondary to an increase in net calcium flux across the placenta to the fetus. Transient suppression of fetal parathyroid function may result in severe neonatal hypocalcemia that leads to seizures (17). Neonatal hypocalcemic tetany, which usually occurs during the first 72 hours, may depend on maternal PHP (18).…”