Neonatal hypocalcemia due to asymptomatic maternal primary hyperparathyroidism.

Neonatal hypocalcemia resulting from maternal primary hyperparathyroidism (MPH) is usually detected clinically in the first 2 weeks of life. Occasionally, diagnosis of primary hyperparathyroidism in a young asymptomatic mother is made when the infant presents with hypocalcemia. We present an infant with late onset hypocalcemia resulting from a combination of transient hypoparathyroidism due to asymptomatic MPH and vitamin D deficiency.