[Neonatal hyperparathyroidism secondary to unknown maternal hypoparathyroidism]

Vitamin D or its analogue (calcitriol) is an effective treatment for hypoparathyroidism during pregnancy. Normal babies are delivered and very few cases of associated neonatal hyperparathyroidism are reported.

We report the case of a baby born to a mother suffering unknown hypoparathyroidism. He was delivered prematurely by cesarean section for birth asphyxia. His mother had had recurrent bouts of impetigo herpetiformis for several months. Severe demineralization associated with decreased plasma calcium level were observed at birth. The PTH level was very high (955 ng/mL) in the baby and very low in the mother, leading to the diagnosis. The baby was given intravenous calcium gluconate, oral 1 alpha-hydroxyvitamin D and mechanical ventilation. Normal plasma calcium level was reached on day 2. PTH level improved by one month of age. Because of impaired respiratory mechanics and bronchopulmonary dysplasia, the baby was kept on ventilation for 58 days. By 20 months of age, he was in good health despite a small height for his age.

In such cases 1 alpha-hydroxyvitamin D seems to be very effective but plasma and urinary calcium levels need careful monitoring.