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Sticky Blood-Hughes Syndrome Support
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CFX ( chromogenic Factor X) Assay

*I’m including my results on a few draws compared in IV vein value draws, as well as coagucheck Finger prick values.

This , my hematologist, confirms I’m likely now Lupus Anticoagulant Antibody Positive as well. ( likely I’ve “picked up “ the third anti body.)

I was origionaly only positive for aCL and B2GP1, but developed a large DVT about a week after the second set of tests came back positive, so was hospitalized with heparin IV and bridged to oral warfarin for life, so could never be tested for LAC Antibody activity again accurately. This discrepancy is a pretty clear indicator I have also the third Antibody presence , LA.

I’m going to include a second post ( as is often the case with my posts) with another photo on how to interpret the CFX percentage ( adjustment) off of the known Vein value “ traditional INR.

There is great controversy regarding the usefulness of this test. I think the biggest problem is it is not ,” real time.” It’s not real time user friendly.

It’s more useful in showing a trend for long range understanding of your personal disease process.

My personal numbers numbers were lovingly plugged into MAT LAB for me by my scientist daughter.

Straight up shows same day. Some days there is quite a discrepancy- others not so much.

I am a very steady and stable patient with regards to how much greens are in my diet and what time of day I take my warfarin. ( Brand name Coumadin for me.) I take 17mg each night at 9:00pm. I take 1 jr strength aspirin each morning ( here in USA it is 81mg.) at 9:00am.

6 Replies

If you are on warfarin its likely you can have a false positive for LA. Normally they don't test LA if on warfarin because of this. Ive not heard of CFX. x


Yes. It was not a test for LA per se. just a metric to see , in another way, if my vein value INR was actually “ reflective “ of an actual true vein value .

It can be a useful for two purposes.

1. A “ back door way “ to see just how far apart the vein value is off if lupus Anticoagulant Antibody is suspected but warfarin has already been commenced.

This helps determine risk factor for clotting in future for some patients... but only by some statistics. Many publications find anomalies aplenty.

2. For me- and I now believe possibly for others on the forum.. to help determine the value in auto immune suppression. If a patient is actually NOT properly anticoagulated- that makes the topic of suppression quite different. The conversation of risk vs benefit with regards to both clotting / bleeding/ Lower immunity becomes readjusted.

It’s all about education, education, education. Is this test of value? In what circumstances? I’m just not sure yet.


And are you finally feeling relief?


Compared to Thanksgiving time, absolutely!

I’m living my life pretty normally.

I wish I were not having ( approx) migraines about once a week. I think they are sure to INR shifting around too quickly. Too big of swings in too short of a time.

I feel the best if my true INR is above 4.0 - 4.5 and steady there. I think this is about right for the majority of us.

Like the majority of us with LA Antibody... steady is the challenge.

I wish so desperately I would not have instantly failed the LMWH injections regiment and reclotted.

However- I’m very stable with my diet on warfarin- I just always worry about viruses... and medications should I need them. I would prefer the freedom to not worry about getting a cold... and taking an antihistamine! ( just an unthought through example. Off the cuff. You know what I mean.)


I sent you an email did you get it?




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