New Zealand surveillance of neonatal vitamin K deficiency bleeding (VKDB): 1998-2008.

AIM: To undertake surveillance of vitamin K deficiency bleeding (VKDB) from 1998, through the transition to a new single licensed vitamin K preparation in 2001, to 2008.

METHODS: VKDB was listed with other rare conditions on the card sent monthly to registered specialist paediatricians by the New Zealand Paediatric Surveillance Unit with a request to indicate whether or not a case had been seen in the previous month. Those notifying a case were sent a two-page questionnaire. The main outcome measures were incidence of VKDB of early (first day of life), classic (days 2-7) and late-onset (day 8 to 6 months) type; related morbidity and mortality; receipt of vitamin K; and predisposing factors.

RESULTS: Response rate of return of surveillance cards was high, averaging 94.5%. There were 35 notifications of which 23 were valid cases. Seventeen cases met criteria for confirmed VKDB, two for 'probable' and four for 'possible'. There were eight confirmed classic cases with an overall incidence of 1.24 (95% confidence interval 0.54-2.45) per 100,000 births; none had received vitamin K prophylaxis, seven were fully breastfed and all fully recovered. There were nine confirmed late-onset cases with an overall incidence of 1.40 (95% confidence interval 0.64-2.65) per 100,000 births; eight had received no vitamin K, eight were fully breastfed, six had liver disease, four suffered an intracranial haemorrhage and one died.

CONCLUSIONS: In New Zealand, VKDB is virtually confined to fully breastfed infants not given vitamin K at birth. Late-onset cases were frequently associated with liver disease.