Intracranial hemorrhage and vitamin K deficiency in early infancy.

We report late-onset (1/2 to 6 months of age) intracranial hemorrhage related to vitamin K deficiency in 32 breast-fed infants, 31 of whom received no prophylactic vitamin K at birth. Computerized tomography showed mild to severe intracranial hemorrhage. Most (90.6%) had subarachnoid hemorrhage, either alone or in combination with subdural hemorrhage (37.5%), parenchymal hemorrhage (31.3%), or intraventricular hemorrhage (12.5%). In three (9.4%) the infratentorial region was involved.