予防し得なかった特発性乳児ビタミンK欠乏症の2例

抄録

Two cases of Idiopathic vitamin K deficiency in infancy we experienced recently are reported. The first case was admitted to Kanagawa Children's Medical Center at 62 days of age, because of intracranial hemorrhage due to vitamin K (VK) deficiency. She fell ill in spite of prophylactic administration of oral VK at her birth and 6 days after birth. She exhibited hyperbilirubinemia and elevation of serum transaminase. It was suspected that Cytomegalovirus (CMV) infection was related to her liver dysfunction, because IgM antibody to CMV was increased and CMV was isolated from her urine and breast milk of her mother. The second case was admitted at 31 days of age, and made a diagnosis of subdural hemorrhage and hemothorax due to VK deficiency. He had not received VK administration prophylacticaly, because his Normotest was normal at 6 days of age. He exhibited slight elevation of serum transaminase on admission. However CMV infection could not be elucidated in this case. We think that liver dysfunction plays important role in the onset of VK deficiency in infancy.
The prophylactic administration of VK during the neonatal period has been carried out widely in Japan, and a remarkable decrease of intracranial hemorrhage due to Idiopathic VK deficiency in infancy has been reported. It is important to study the cases that failed to be prevented, for making a plan to prevent VK deficiency in infancy furthermore.