Investigators from multiple Australian institutions conducted a prospective cohort study to assess the incidence of vitamin K deficiency bleeding (VKDB) in infants <6 months old. Cases of VKDB were identified through monthly solicitations of pediatricians and other child health specialists participating in the Australian Pediatric Surveillance Unit, who report occurrences of several conditions of interest, including VKDB. Solicitations began in 1993 and continued through 2017. VKDB was defined as spontaneous bruising, bleeding, or intracranial hemorrhage associated with prolonged clotting times that was not due to disseminated intravascular coagulation or an inherited coagulopathy. For each VKDB case reported, pediatricians were asked to provide case demographics, clinical characteristics, lab results, type of vitamin K prophylaxis received (intramuscular [IM], oral, or none), and outcome.
Cases of VKDB were categorized as definite if there was a clinical history consistent with VKDB as well as complete coagulation results. A case was probable if a clinical history was consistent, but coagulation results were incomplete. VKDB cases also were classified by age of onset of bleeding: early within 24 hours of birth, classic between 1 and 7 days, and late between 1 week and 6 months of age. Investigators calculated the annual incidence of VKDB between 1993 and 2017 per 100,000 live births using population estimates published by the Australian Bureau of Statistics.
There were 58 reported cases of VKDB (47 definite and 11 probable) during the study period, corresponding to an annual incidence of 0.84 per 100,000 live births (95% CI, 0.64–1.08). Most cases (72%) were classified as late VKDB. Vitamin K prophylaxis had been given to 43% (N=25), including IM to 14 and oral to 7 cases of VKDB. Among the 33 cases in which no vitamin K prophylaxis was given, 85% (N=28) were due to parental refusal. There was a higher proportion of parental refusal of vitamin K prophylaxis among VKDB cases from 2006–2017 (63%) than 1993–2005 (32%).
Overall, the most common sites of bleeding among cases were cutaneous (45%), gastrointestinal (34%), and intracranial (29%). There were 6 deaths, all from intracranial hemorrhage in infants with late VKDB. In 3 of these cases, parents had refused vitamin K; in the other 3, IM prophylaxis had been given.
The investigators conclude that the overall incidence of VKDB is low, but cases of VKDB due to parental refusal of vitamin K prophylaxis are increasing.
Dr Mintzer has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.
Families refuse birth vitamin K administration for a variety of reported reasons. Factors affecting vitamin K administration decisions include perceived risks, a preference for a more “natural” childbirth experience, potential mistrust in allopathic medical practices, and/or reported unfavorable experiences with...