Parathyroid gland hemorrhage in perinatally lethal osteogenesis imperfecta.

In four neonates with perinatally lethal osteogenesis imperfecta (OI) who survived for more than 9 days after birth, vascular congestion and acute hemorrhage were found in 10 of 11 parathyroid glands; in one neonate, all four parathyroid glands, including the only gland without acute hemorrhage, contained abundant deposits of stainable iron. One neonate had hypocalcemia, and one had both hyperphosphatemia and hypocalcemia. In four neonates with OI who died within 72 minutes of birth, all 10 parathyroid glands demonstrated were free of hemorrhage and hemosiderin deposition. Only minor foci of acute hemorrhage were seen in three of 170 glands in 113 comparison neonates and infants. We conclude that parathyroid gland hemorrhage is common in perinatally lethal OI with survival beyond the immediate period of birth, and is otherwise rare. We speculate that parathyroid hemorrhage may be related to difficulty in maintaining postnatal calcium homeostasis in the absence of adequate calcium reserves in bone. Acute parathyroid gland hemorrhage causes fluctuations in serum calcium levels that have on occasion proved fatal, and parathyroid hemorrhage may be a proximate cause of death in some neonates with OI.