INR Self testing for triple + patients

[Px123]

Hi All,

I am triple + aps, well controlled on warfarin and HCQ. INR pretty stable between 2-3. My only past symptom was a sizeable dvt two years ago which prompted the diagnosis. I have been testing 2x month through venous puncture but lately that is pretty painful. I am considering starting self testing at home through Coagucheck but have read it’s not reliable for triple positive patients. Would love any input on your experiences with the reliability of self testing. Thanks much! Be well.

[Ray46]

It is not reliable for some APS patients whether triple positive or not (I have heard that being LA+ve is the worst for making it unreliable).

The only way to find out if it is reliable for you is to test it, which means getting venous and fingerprick tests done at the same time for comparison, and doing that over a period of time to check that any offset/difference is not too large and is stable. I think I was on comparison testing for 3-4 months before being given the OK to use fingerprick testing.

I still have a review and comparison test at least every six months, and if fingerprick results go suddenly high without explanation I still have to get a venous to check what is going on, but my veins and elbows are a lot happier.

But, end of the day, you need to talk to whoever provides your anti-coagulation service - this isn't something you can do (at least not safely) without them.

[Bobbydoodle]

I’ve never heard this before. I just have the finger prick test at the clinic. I didn’t realise it wasn’t reliable for APS.

I’m in the UK where are you based?

[Px123 in reply to Bobbydoodle]

Only for triple positive APS, from what I have read and my docs have said. I’m in the US.

[Bobbydoodle in reply to Px123]

Thanks. I’m triple positive but must be different in the UK as that’s never been mentioned to me.

[Jianna35]

I'm not triple positive but my INR is way out with finger prick compared to venous sample. My warfarin dose goes between 7 and 16 and is completely unstable. Just reduced from 15.5 to 14.5 after INR shot up now it has gone up even more...lol. It was the opposite at the beginning of the year took months to get it within range and ended up hospitalised because I became sensitive to Fragmin. Get venous test along with finger prick and see how they compare, is my advice.

[Px123]

Good advice. Thanks to all. Going to urge docs to green light the side by side for a while.

[MaryF Administrator]

Hiya whether triple positive or not, the side by test is usually recommended to see how they compare over time, as you are aware testing can be crucial like this due to the INR being unstable at times in some people. If your GP/consultants is supporting you with this extra layer of testing, do let us know what they say and how it is going. MaryF

[MickyPitt]

The problem is that many if not all of the test strips for the home machines use lupus anticoagulant as the reagent on the test strip. So if you have lupus anticoagulant in your blood, it cannot produce a reliable INR (the numbers are very high positive and not valid). That’s why triple positive patients can’t usually use home machines.

[Px123 in reply to MickyPitt]

Thank you for that explanation. No one has told me that! Really appreciate it.

[KellyInTexas Administrator in reply to Px123]

That’s it exactly. I’m one of the ones who can’t use…

Also- must test at the same time. Take your coagucheck in with you to lab, or at least in waiting room.

Also- make sure test strips stay temperature stable. ( and not exposed to sunlight.)

[Lure2]

When I read this I wonder one thing: do you have a Specialist of autoimmun illnesses who works with such patients and who is knowledable of APS. Why I ask is that most Specialists usually find a higher INR for triplepositive patients incl Lupus Anticoagulant are needed to avoid further clots, TIAs, DVTs and PEs etc. There are also microembolies and microclots and those are difficult very often to show on a normal Scan of today.

When you had your DVT 2 years ago were you already on Warfarin at that moment or any other anticoagulation drug? As I guess you were not as you write you were not diagnosed with APS then.

I live in Sweden and I am tripplepositive with high titres all the time and I need an INR of around 4.0 to loose symptoms.

[Px123 in reply to Lure2]

I have docs through John’s Hopkins. my heme consults with a lupus specialist but since I do not have any other symptoms, I do not see the specialist directly. So the docs keep my INR between 2 and 3. I was not on warfarin when I had my dvt so had no idea I was aps triple +. I think docs are just taking a conservative approach bc I am lucky to not have other symptoms currently. I’m on HCQ as well as a prophylaxis.