Factor VIIa in patients with C1-inhibitor deficiency

E. W. Nielsen, J. Morrissey, J. O. Olsen, B. Osterud

Research output: Contribution to journalArticlepeer-review


In hereditary angioedema (HAE), normal C1-inhibitor (C1-INH) is low and the contact system activated. Recently, the findings of a tissue factor mutant selectively deficient in promoting the conversion of FVII to FVIIa, but with retained cofactor for FVIIa, made it possible to examine reliably the pre-existing content of FVIIa in HAE patients. This was of interest as FXIIa (mainly inhibited by C1-INH) is able to activate FVII directly. FVIIa in 21 remission HAE patients were within normal limits but nearly doubled as compared to their 23 normal siblings (p = 0.0017). Cold promoted activation of FVII (CPA) (common clot assay) was displayed in plasma of all 5 untreated patients (C1-INH function < 35%), but not in plasma of 2 patients treated prophylactically with danazol (C1-INH function about 40%). These results suggest that there is a minute, yet significant activation of FVII in patients with C1-INH deficiency.

Original languageEnglish (US)
Pages (from-to)1103-1106
Number of pages4
JournalThrombosis and Haemostasis
Issue number4
StatePublished - 1995
Externally publishedYes

ASJC Scopus subject areas

  • Hematology


Dive into the research topics of 'Factor VIIa in patients with C1-inhibitor deficiency'. Together they form a unique fingerprint.

Cite this