Vitamin K prophylaxis and late vitamin K deficiency bleeding in infants: fifth nationwide survey in Japan.

Background: In 1980, the first nationwide survey on late vitamin K deficiency bleeding (VKDB) in infants was conducted in Japan, and it was followed by the second, third and fourth nationwide surveys in 1985, 1988 and 1991, respectively. The fifth nationwide survey was designed to ascertain the epidemiology of late VKDB between January 1999 and December 2004.

Patients And Methods: Questionnaires were sent to 2161 hospitals in Japan that employed members of the Japan Pediatric Society in March 2005. Responses were received from 1373 hospitals, for a response rate of 63.5%.

Results: The total number of reported cases was 71, including 21 idiopathic type and 16 secondary type. The incidence of late VKDB was estimated to be 1.9 cases per 100,000 births (95% confidence interval: 1.2-3.0) during this survey period. In 34 cases, the presence or absence of any underlying disease was not clarified. A total of 67/71 infants were entirely breast-fed. Intracranial hemorrhaging was observed in 26 (63.4%) out of 41 infants whose bleeding sites were described in the questionnaires. In 63 cases (88.7%) of late VKDB found in the present survey, however, vitamin K had been given at least once either during or after the neonatal period.

Conclusions: A reevaluation of the current prophylaxis strategy for late VKDB in infants is necessary.