Summary
Severe hemorrhagic disorder due to congenital factor XIII deficiency is described
in two unrelated Norwegian girls.
Plasma cephalin time was for both patients extraordinarily short during episodes of
bleeding and hematomas. No such hyperactivity reaction was demonstrable in unaffected
condition some months later.
Estimations of blood factor XIII levels revealed a partial defect in the parents of
both children, and also in some other family members, consistent with an autosomal
incompletely recessive inheritance of the defect. Some of the presumptive heterozygotes
had a history of light bleeding phenomenons; whether this was related to their partial
lack of factor XIII is so far uncertain.
