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.

Normally I wouldn't copy and paste like this, but I've been doing a little "light reading" lately and what I'm reading is absolutely absurd!!

Let's take example #1 for instance:

You are welcome to your opinion about the accuracy of the machines but I have not seen any study or data that indicates it is less accurate than a lab test? I think it is just the opposite and more accurate than many lab tests. For the lab test you have the draw, the handling, the storage, the transportation, a time lag that can be up to several days before the test is really done and all of these can contribute to a wrong result from the test.
Different tests (reagents at least) are used in different labs. With the machine, the blood is always fresh, everything is automatic and there is almost no chance for an inaccurate test. In addition you don't get collapsed veins or someone jabbing you and moving the needle around trying to find a vein. Add in the ease of not needing to even leave the room, getting the results in minutes, available at any time day or night and even on holidays and I can understand why someone might want to use a machine. The machines in Doctors offices and some labs are the same machine used at home.
BTW, I would suggest anyone who gets a strange reading, high or low, from a lab (or a machine) should have the test repeated as labs do make mistakes and we need to be certain ours are right before we make any drastic changes. This is much easier to do if you have a machine.

Now if we break this down a bit and look at the facts. The companies that make these home testing machines put disclaimers in their package inserts about APS patients and possible inaccuracies. No data? There's data from the company who make the machines.

True that when the blood is tested with the machine it's fresh. There are no handling issues and yeah, it's a lot more convenient. However...is convenience worth the risks that possibly having a WRONG reading will cause?

What happens when an APS patient's INR is too high? They could have a bleed...which, although may not be life threatening, could be very dangerous. What happens when an INR patient's INR is too low? They could have a clot. Maybe it will be "just" a DVT....hmm, but couldn't a DVT lead to a PE...and couldn't the clot be a stroke instead of a DVT?

So convenience basically is worth the risks of an inaccurate test and a possible bleed/clot?

I guess it is for some people.

Another example to consider:

I will say that I was told by others with APS that it is dangerous for us to use. I saw the success that so many in the UK are having, so I asked my hemo (after I found a good one that speaks frankly with me). He said that if you have the intelligence to calibrate the machine and you can learn through your doctors guidance to understand how to make simple adjustments and know when there is an emergency... He believes the machines are very helpful. He said that given the patient more control over his/her healthcare is beneficial in many ways. When I asked specifically about the things I read about APS patients, he said it was "nosense"
and maybe a "scare tactic of someone that likes drama" (His words, not mine). He explained that if you get a false high reading on the home machine, you are going to get a false high at the lab.

So...if a patient has the intelligence to calibrate the machine then they should be all set? Well, with simple adjustments and such. So what would be the reason that an office or clinic's machine would give a false reading? Perhaps the nurse or whoever in the medical field working in the office/clinic wasn't "intelligent" enough to calibrate and adjust the machine so the reading wouldn't be inaccurate. I'd certainly trust a nurse more than myself...and don't we have a story about someone who's CLINIC reading was off with the finger stick machine?

And remember we're not only talking about false HIGH readings, but also false LOW readings. Personally, the low ones would scare me more than a too high reading.

On to my third example:

I would never recomend one of these machines to a person who was permanantly positive for LA as the machine would just not worg for 33% of them (the other 66.6% would still be OK, but the constant worry of a possibility of a false high would be too much to bear. For the vast masjority of patients these machines are helping them in their daily control of the disease and helping them keep complete records to share with others on what effects their day to day INR levels.

APS antibodies tend to wax and wane. Basically, you may be positive for the LA one month and not be the next...or maybe you've have 15 tests and been positive for it once...this does happen in APS patients.

33% with a positive LA may have inaccurate readings. Let's break this down a bit. If you have a positive LA and you get your INR drawn 90 times with a finger stick machine, 30 of those have the potential of being inaccurate. Do you know when those 30 times are going to happen? Can you guess or determine when by how you're feeling on any given day? Should you have to guess at all?

Would you buy a computer that worked 66% of the time? How about a car? Would you want your electricity or heat to only work 66% of the time?

Would you pick a doctor who misdiagnosed people 33% of the time?

I don't know...to me, the proof is in black and white. The data is in black and white. Maybe there's not an official "study" but there is literature out there.

Educate yourself before you buy into this INR machine business. Convenience isn't always the "best" way.

Let's also consider this: the word "may" is used a lot in these types of posts. Basically, it's used to cover the poster's ass. And yes I know, I use it too...but think about it:

• Stool softeners "may" cause diarrhea.
• Condoms "may" stop the transmission of STDs.
  

Don't take MY word for it...after all, I'm just someone who's using "scare tactics" to stir up "drama"....when actually, I'm only doing that 66% of the time. *insert eyeroll here*

Ahh....another machine not working.

i also have aps, history of one stroke, with recurrant clots while on coumadin.
i had the protime, and when checked against the lab, was found to be faulty.
i was told by the company that it may be inaccurate for people with the lupus anticoagulant.
be careful, and once in a while check it against the lab. the differences i had were alarming.
the company apologized, said i shouldnt use it, and refunded my money. that was in 01.

Originally posted on Healthboards:
http://www.healthboards.com/boards/archive/index.php/t-352980.html

Every few months or so the topic of home INR machines is brought up and as of late, debated, on APS support forums and e-lists.

It appears as though certain groups are pushing people to get the machines and even promoting the purchase of the machines (as if they were getting a kick back from them?). And then there are other groups who are adamantly against the machines.

These machines have put into their literature that there are "limitations" when it comes to APS patients. They mention those who have a positive Lupus Anticoagulant, however, listed here we have a personal story from someone who has a negative LA and actually has Seronegative APS or SNAPS and she had problems with her home machine.

Did you know that there can be other factors that can also affect the readings? Anemia is one thing, and also Lovenox/Heparin use within 24 hours of the reading can cause it to be off.

If you needed a carseat for your child and there were only two to choose from…would you buy the one that had listed certain "limitations" or would you go for the one that was deemed "safe"? Maybe not a good comparison, but the warnings are in black and white. Who can question that?

If you get your INR from your home machine and have to "add or subtract a point" because you KNOW it's off…what does that tell you?? What if it's off by 2 or 3 points and you only added 1? So then a 2.2 reading…+ 1 pt would be 3.2…but it's off 2, so your TRUE INR is actually 1.2??? Do you know what can happen to some people when their INR drops that low?? Clots…Strokes…PE's…

Is the convenience of having the machine at home worth risking your life over?

I am urging you to educate yourself. Call the companies, ask the questions. If your doctor is pushing this machine, do they get money for each machine sold? Same with an organization that may be pushing it…are THEY getting money for each machine sold? Talk to people who use the machines. Ask them how often they do comparisons with a vein draw. Read the stories of people who have had problems. 1 in 10 is one too many if you ask me.

Educate yourself. Make an educated decision, not a knee jerk, convenience decision. The "limitations" are in black and white. If you have APS…YOU are the limitation.

This is also referring to the finger stick machines at the clinics or dr offices. One of the stories was from a dr's machine and not a home machine.

It's your life, your decision. Is the convenience of not going to the clinic worth your health and possibly your life? How convenient will it be for yourself, your family, friends and loved ones if you're dead?

These are excerpts taken from a thread in the APS Friends and Support forum located at www.apsforum.com.

How about the finger stick in the hospital lab? I like it because I know my INR right away. But if the elbow stick is more accurate.... The only time I had both a finger stick and the elbow stick, the numbers were the same.

I had the chance to get a little evidence on my own. I had a blood draw from the doctor's, and asked them to do a pt/inr, then I went straight to the hospital where I have a standing order. and got a finger stick. the finger stick was 1.9, the venopuncture was 2.3. Venopuncture from now on.

I'm going to tell the people at my hospital that APS people shouldn't get fingersticks. I think we all should tell our doctors, phlebotomists, vampire people, etc. that venous is the only way for us APS folks. They don't necessarily read the literature, and APS is such a new diagnosis that they haven't learned this in school, and it hasen't hit the continuing medical education courses. So we 'special ones' surround us with people who do know that. lrb

http://www.apsforum.com/forum25/10469.html
(registration required)

I gave the finger prick test a try, too. Came back as 4.1, so they said "great, let's leave your dosage alone." I told the dr that I was not confident in that result because my body was telling me that my INR was below 3. I asked to be sent to the hospital for a stat venous draw. They humored me and I had the stat draw within 10 min. It came back 2.3. No more finger stick for me! The dr called the company (INRatio) and the company said it wasn't accurate for a lot of people with APS. Now, the dr is trying to find out which of her patients have APS, so she can check all of them as well.