TABLE 1

The 3 Patterns of VKDB

PatternaDefinition
EarlyDefined as bleeding caused by vitamin K deficiency in the first 24 h of life, usually because of vitamin K deficiency in the mother. Early VKDB is rare, and it is typically seen in conjunction with maternal use of drugs that interfere with vitamin K metabolism such as anticoagulants (warfarin), anticonvulsants (phenytoin), and antituberculosis drugs (rifampicin and/or isoniazid).10 It is frequently life-threatening because common bleeding sites include the head (cephalohematoma, intracranial, and subgaleal), intrathoracic and/or abdominal cavities, and the gastrointestinal tract.8
ClassicOccurs during the first wk of life, and the most common bleeding sites are gastrointestinal sites, umbilical sites, the skin, nose, and wounds (eg, postcircumcision). Intracranial hemorrhage may occur, but it is rare.8
LateLate VKDB encompasses bleeding that occurs between 8 d and 6 mo,9 with the peak incidence generally occurring between 3 and 8 wk of age.11,12 Late VKDB occurs almost exclusively in breastfed infants.13 Late VKDB can have similar etiology to classic VKDB (low milk intake and low vitamin K content of milk), and it can also be precipitated by fat malabsorption caused by gastrointestinal or hepatobiliary disease, such as biliary atresia.14,15
  • a It is also usual to distinguish between idiopathic and secondary VKDB. Secondary VKDB has a known underlying cause (eg, congenital hepatobiliary or malabsorptive disorders) or results as a consequence of medications given to the mother or infant.8