Case-by-case decisions on when to test
The decision on whether to evaluate for a bleeding disorder may be made case by case.
If there is no obvious known trauma or intracranial hemorrhage (ICH), particularly subdural hematoma (SDH) in a nonmobile child, abuse should be suspected, the authors write.
They acknowledge that children can have ICH, such as a small SDH or an epidural hematoma, under the point of impact from a short fall.
“However,” the authors write, “short falls rarely result in significant brain injury.”
Conditions may affect screening tests
Screening tests for bleeding disorders can be falsely positive or falsely negative, the authors caution in the technical report, led by Shannon Carpenter, MD, MS, with the department of pediatrics, University of Missouri–Kansas City.
- If coagulation laboratory test specimens sit in a hot metal box all day, for instance, factor levels may be falsely low, the authors explain.
- Conversely, factors such as VWF and factor VIII are acute-phase reactants and factor levels will be deceptively high if blood specimens are taken in a stressful time.
- Patients who have a traumatic brain injury often show temporary coagulopathy that does not signal a congenital disorder.
Vitamin K deficiency
The technical report explains that if an infant, typically younger than 6 months, presents with bleeding/bruising that raises flags for abuse and has a long PT, clinicians should confirm vitamin K was provided at birth and/or testing for vitamin K deficiency should be performed.
Not all states require vitamin K to be administered at birth and some parents refuse it. Deficiency can lead to bleeding in the skin or from mucosal surfaces from circumcision, generalized ecchymoses, and large intramuscular hemorrhages or ICH.
When infants don’t get vitamin K at birth, vitamin K deficiency bleeding (VKDB) is seen most often in the first days of life, the technical report states. It can also occur 1-3 months after birth.
“Late VKDB occurs from the first month to 3 months after birth,” the authors write. “This deficiency is more prevalent in breast-fed babies, because human milk contains less vitamin K than does cow milk.”
Overall, the authors write, extensive lab tests are usually not necessary, given the rarity of most bleeding disorders and specific clinical factors that decrease the odds that a bleeding disorder caused the child’s findings.
Dr. Joos said the decisions described in this paper are the kind that can keep pediatricians up at night.
“Any kind of guidance is helpful in these difficult cases,” he said. “These are scenarios that can often happen in the middle of the night, and you’re often struggling with evidence or past experience that can help you make some of these decisions.”
Authors of the reports and Dr. Joos declared no relevant financial relationships.