Factor X deficiency in the neonatal period.

An infant with a severe deficiency of factor X presened in the neonatal period with uncontrollable bleeding from heel prick sites, spontaneous bruising, and haematoma. The deficiency was controlled by infusions of dried human factors II, IX, and X concentrate; the half-life of the infused factor X material is only 18 hours. Despite prophylactic weekly infusions of factor X concentrate, the child developed a fatal intracerebral haemorrhage when only 4 months old. Coagulation studies on both parents and the elder sister showed no obvious coagulation abnormality.