Antiphospholipid Antibody Syndrome (APS) - SAY NO to Home INR and Finger Stick Machines!!

Did a little more light reading. Have more to add as far as this topic goes.

What keeps being brought up is this positive Lupus Anticoagulant. The companies who manufacture the top couple or few INR testing machines have a disclaimer in their package inserts about possible inaccuracies in readings with APS patients who have a positive LA. The links are on the side and I believe they say something about a false high reading. And I've already discussed the whole 1/3 or 33% issue.

I found the following little blurb interesting:

The first document is from Roche, and it does not say in all cases, and it does not even infer that it means all cases. This is a matter of interpretation. It does say:

The presence of anti-phospholipid antibodies (APAs) such as Lupus antibodies
(LA) can potentially lead to prolonged clotting times, i.e., elevated INR values. A comparison to an APA-insensitive laboratory method is recommended if the presence of APAs is known or suspected.

Yes it says a laboratory comparrison is needed when the presence of LA is is known or suspected. As LA activity is transient, that could be just once in three years of tests, as it has been with my tests.

Do you, as an APS patient, know when your LA is positive? Does a little light go off somewhere to indicate that your LA is positive today and your INR test may be off? Are you SURE? 100% no questions SURE that your LA is positive on xx day?

Would you be willing to bet your life on it?

If you go by what that blurb above says then you are. So you're telling me you know the EXACT date or let's say time of year, when your LA is positive and are going to be expecting a false reading from your beloved machine.

If you don't...how did you know that your INR was off in that ONE test in 3 years? Do you get a vein draw comparison EVERY time? No? Then you can't REALLY, honestly say that your INR was correct...can you?

You're putting a lot of faith in a little machine that the manufacturers warn is not completely accurate for APS patients.

What about those people who don't have a positive LA....what would then make their tests be off? Something to ponder.

Next statement:

The exact wording is:

Studies indicate interferences may occur in patients with antiphospholipid antibodies or antiphospholipid syndrome.

- Sanfelippo MJ, Sennet J, McMahon EJ, 2000. Falsely elevated INRs in warfarin-treated patients with the lupus anticoagulant. WMJ. Jun; 99(3):62-4, 43.
- Rosborough TK, Shepherd MF, 2004. Unreliability of international normalized ratio for monitoring warfarin therapy in patients with lupus anticoagulant. Pharmacotherapy Jul; 24(7):838-42.
- Perry SL, Samsa GP, Ortel TL, 2005. Point-of-care testing of the international normalized ratio in patients with antiphospholipid antibodies.
Thromb Haemost. Dec; 94(6):1196-202.

The important word there is' may'. If I said the world MAY end tomorrow, would you think it was going to as a matter of fact? No, you would probably assume that anything MAY happen but you doubt if the world will end.

I'm going to focus on the last paragraph, but didn't want to take it out of context. The important word is "may". That I agree with. But...and you knew a but was coming...I have this to say. If I knew the would "may" end, I would at least be prepared for it to end. I'd spend the day with loved ones, eat my favorite foods, get really drunk, try something I'd always wanted to do but never did...etc. If I knew that 33% of the time my car may not start, I'd be sure I had roadside just in case. I'd want to be prepared. If I knew that the school my children were supposed to go to "may" have asbestos, I would probably find a new school.

People who buy these machines are going by recommendations from the medical community (who are probably getting some sort of kickbacks), from organizations (who are also probably getting kickbacks) and individuals who use the machines (and I'm not convinced some of them aren't ALSO getting kickbacks). They may or may not be buying them blindly, without knowing that 33% of the time they may have an inaccurate reading with a positive LA. They might not have done the research necessary to get the full picture. Not just the rosy painting that the many people who successfully use these machines paint for them...how wonderful it is to have the freedom to check your INR from home and not have to have the inconvenience of going to the lab and waiting for the vein draw. They may not know that these machines are known to have inaccuracies in some APS patients.

On to the third statement:

I know I have, and many others who have the sence and knowledge to understand the possiblity of a false high then there can be no problem. As for those who cannot use the machine at all, Roche (the only manufacturer I mention) will offer a full money back warranty if it is agreed prior to purchase. You can't be fairer than that for those few who cannot use the machine at all.

Why can there not be a problem? Just because you know there can be a false high? Do you know WHEN the false high is coming? Why make it a guessing game. For the convenience?

Also...be SURE to ask if the company you're getting your machine from WILL in FACT take it back and refund your money. They may only have a 90 day return policy and say that you find your false readings on day 127. Then you may be stuck with a worthless machine.

My goal is to educate. Know the facts before you buy. Don't buy into the hype. What works for others may not work for you.

I'll leave you with a different kind of quote. From a different source, obviously. (not my words)

I had the same technical data, my hemo's office gave it to me. I think one of the reasons that he switched to that brand from ProTime because it's the machine with the highest accuracy rate (2/3) for APS patients. To me, the bottom line is that even if it works flawlessly for me, or anyone else with APS, it's still wrong in 1/3 of APS patients, and that's just not a good enough success rate. As I said to my hemo, 2/3 is only a good ratio if you're not in the 1/3 that's left over!

And one more...(not my words)

Finger sticks for APS do not work. I have had too many wrong readings that could have put me at risk for a bleed or a clot. I finally got educated and found that the self test machines, and finger sticks are not accurate MOST of the time. It is not worth risking my health because a lab or doctor refuses to monitor my INR the CORRECT way. If they don't want to do my care properly, I would transfer my business elsewhere, no if, ands, or buts!

If you didn't know anything about these machines but how wonderful they are and how convenient they are, then you wouldn't know the risk you may face of false readings. You wouldn't know your life may be at risk because if the reading is a false low and your true INR is much higher then you face a bleed. On the flipside, if your reading is a false high and your true INR is low then you could be facing a clot...and it may not be a DVT, but it may be a PE or stroke that may result in your death.