title: Thromboembolism and bleeding tendency in congenital factor XII deficiency--a study on 74 subjects from 14 Swiss families.
abstract: In order to assess the clinical implications of hereditary F XII deficiency, all available members of Swiss families with F XII deficiency were investigated. Based on the F XII:C values and the family pedigree, the 74 subjects, aged 8-82 years, were classified as homozygotes/double heterozygotes for F XII deficiency (n = 18), as obligatory (n = 20) or possibly (n = 25) heterozygotes, respectively, and as normals (n = 11). None of the 18 subjects with F XII:C less than 0.01 U/ml and only one possibly heterozygous woman had an abnormal bleeding tendency, confirming the notion that Hageman trait generally does not result in a hemorrhagic diathesis. Two of the 18 subjects with severe F XII deficiency had suffered from venous thromboembolic disease at age less than 40 years. One heterozygous woman had a leg ulcer probably due to venous thrombosis. Thus, whereas homozygous F XII deficiency may be associated with an increased risk for venous thromboembolic disease, partial F XII deficiency is not, by itself, a strong risk factor for thrombosis. Whereas 17 of the 18 subjects with F XII:C less than 0.01 U/ml had no detectable F XII:Ag, one cross reacting material-positive F XII deficient subject (F XII:Ag = 0.11 U/ml) was identified. The dysfunctional F XII, present in this subject's plasma and tentatively called F XII Bern, is the fourth abnormal F XII molecule identified so far.
authors.affiliation: Central Hematology Laboratory, Inselspital, University of Bern, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Lämmle
authors.forename: W A
authors.initials: WA
authors.lastname: Wuillemin
authors.forename: I
authors.initials: I
authors.lastname: Huber
authors.forename: M
authors.initials: M
authors.lastname: Krauskopf
authors.forename: C
authors.initials: C
authors.lastname: Zürcher
authors.forename: R
authors.initials: R
authors.lastname: Pflugshaupt
authors.forename: M
authors.initials: M
authors.lastname: Furlan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001681:Biological Assay; D002648:Child; D005175:Factor XII Deficiency / Q000150:complications / Q000151:congenital* / Q000235:genetics; D005260:Female; D006470:Hemorrhage / Q000209:etiology*; D006801:Humans; D015151:Immunoblotting; D005779:Immunodiffusion; D008297:Male; D008875:Middle Aged; D013557:Switzerland; D013923:Thromboembolism / Q000209:etiology*