Coagulation laboratory tests
Factor IX assay

Author: Jeremy Parsons M.D. (see Authors page)

Revised: 13 May 2016, last major update November 2012

Copyright: (c) 2002-2016,, Inc.

PubMed Search: Factor IX assay [title]

Cite this page: Factor IX assay. website. Accessed October 18th, 2018.
Definition / general
  • To detect congenital or acquired factor IX deficiency
  • Congenital factor IX deficiency (hemophilia B) is inherited as a sex - linked recessive in 1 per 30,000 males
  • Acquired factor IX deficiency is seen in liver disease, vitamin K deficiency, Coumadin therapy
  • A linear, dose - dependent, false decrease is caused by bivalirudin, lepirudin, argatroban, and fondaparinux (Arch Pathol Lab Med 2004;128:1142)