From Heather DeVries, Indiana University. Hello George! We have a physician requesting a factor V antigen assay. I have not been able to find it anywhere. Do you know if there is an assay for this? If so, who performs it? Thanks! Heather.
Hi, Heather. I checked the usual specialty reference labs and the companies who make niche products, and find no reference to a factor V antigen assay. Given your experience, I’m certain you’ve already checked with the physician to ensure she doesn’t mean the factor V Leiden mutation assay. This ordering issue seems to arise daily in large hemostasis laboratories. Meanwhile, perhaps one of our participants knows of a source for a factor V immunoassay.
Added April 24, 2016: Ali Sadeghi-Khomami, PhD, lead scientist at Precision BioLogic Inc., has located a factor V antigen assay produce by Hypen BioMed and marketed in North America by Aniara. Below see a comment by Dr. Emmanuel Favaloro describing the relative value (or lack thereof) of the factor V antigen test.