Different INR readings from Finger pick and lab.

I had a pin sized cut that I must have washed the scab of when washed my hands it bleed for a good 25 minuets, it is litterally smaller then the tip of a pen I did Home INR at 11 it red 4.3 I got my lab results from blood draw INR test that was drawn @ 9:55 it that result was 3.39??? I have all three APS blood disorders plus three additional clotting disorders. Neither result is typical for me with that much bleeding especially from a 4 day old tiny tiny scratch. Which reading is closest to correct? I usually head to lab for my blood draw right after I take Home test (on days I’m going to double check) but couldn’t get both done I a more timely matter. Generally for me to have a bleed like that the INR is higher then either test. Can they both be wrong? Getting frustrated as neither warrant such bleeding? I generally believe the lab or Home but they are always off, as expected. Previously I had Home INR of 5 lab said 4.3. Another time Home test said 3.9 lab test said 3.8. It seems the only consistentcy is that I used same machine at home for all Home tests (coagucheck xs) and went to same lab? Starting to feel I can’t trust Reuther. I know supposed to check both several times and then learn what to add or subtract from Home test but there is nothing clear n my results that I can use? Anybody else having this problem? Any suggestions as which one to believe? Thank you for it time!

30 Replies

  • You may be one of the few that is La positive and yours is affecting your result? Maybe the Home testing is not for you?

    Are you keeping your strips sealed and at room temperature until ready for use? Are you washing and drying your Hands thoroughly before finger pricking?

    Maybe you are not doing something right as per the instructions. I would review your instructions on use and be sure you are doing each step correctly.

    It may just be a simple mistake on your part.

    Review, review, review. Best of luck, Cindy in NJ

  • I cant comment on your INR as I am not on warfarin (clexane) but I can say about bleeding - some days, when I have a small cut it will bleed and bleed, it seems the smaller the cut, the more it bleeds. I sometimes get bleeds from my injection site too. Have been told to put ice on, as this thickens the blood and aids clotting.

    The thing for me, if its a larger cut I always clot straight away so I know its the type of cut and not my levels of blood thinners.

  • Hi Soul-Rebel,

    First of all it this lab "approved" (important to send the reading for evaluation very quick after the draw etc) ?

    It is the vein-test that counts!

    I hope you write all your testsresults down so you can compare. I am triplepositive with LA and high titres also and a big difference between lab-result and fingerprick-test at my CoaguChek XS-machine.

    I have done the doubletests several times before I could be able to rely on the result and know how to do with the numbers.

    When I have a very high INR on my machine the difference is greater compared with the vein-draw at the hospital-lab. If the INR is low one day the difference is not so dramatic.

    If the INR is is too low I also take a LMWHeparin(Fragmin)-shot that day.

    I have to test very often (every second day to) be able to know I am without symptoms and not too low or too high!

    Good Luck!

    Kerstin in Stockholm

  • Lure2

    I am not sure what approval the lab needs but I know when I go in the morning they don’t run it until the afternoon. It’s how they always have done it. U go for a.m. blood draw and call after 3 for results. I have asked multiple times if the red top tube has a chemical to deter clotting and they always say no. But I don’t understand how it can sit all morning without clotting if there is no antagonist in there! I to have all three APS clotttinf issues as well as protein s & c and some genetic clotting issue. I just don’t get y the readings are so far off and off in an inconsistent way! Higher or lower anywhere from .1 to 1.0. So should I make special request for them to run the blood draw right away? What accreditation does the lab need? I live in ROSWELL NM with a population of about 50,000. So not a lot of choices here. Let me know.

    I thank u for always responding to my, often dumb but necessary, questions. 🙂

  • Hi Soul-Rebel,

    Thank you but your questions are not dumb, on the contrary! These things are really difficult to find out and understand!

    I am sorry but I can not follow what you describe about your lab. I am in Stockholm as you know with other routines.

    I just know that the lab must send the bloodtest away fast and I can have my result a couple of hours later in the afternoon when I get home. This is the hospital-lab at my own hospital I speak of.

    I very seldom do doubletests now as I have done so many so I know how to reduce my machine-No down to the right value (which is the vein-value) as I know the DIFFERENCE at a special No is always THE SAME with a little discrepence of perhaps 0,1 - 0,2.

    Hope you could follow me.


  • I would love to be able to know what to add or subtract from Home machines but all comparisons have been completely different each time I am still cluless except when my machine is high I can deduct up to 1.00 Or when it’s low I can deduct 0.1. The differences I am getting are not consistent or even very close. So I guess I just keep double testing and hope to at some point find a happy medium # to add or subtract. What is odd is even the lab draw often does not match my symptoms. I am symptomatic if to high or to low. So I just going to have to stick with my gut until I can find some mathematical system to use to adjust my readings. As my differences btwn lab & home are not even near consultant at this point. I’m sure my lupus anti is acting up which throws things off. I will keep at it until I find a reasonable # to go with.

    Thank you for everything. Also, I have a saying I use to justify my inquiring mind: the only stupid questions are the ones u don’t ask. So I just ask! Have a great day.

  • When I was going to the lab at the hospital they drew into a blue top tube with anticoagulant in it I believe, maybe this is the problem? Have them draw into that tube maybe and see what happens. Curious now. Cindy in NJ😁I will call them on Monday to be sure

  • Yes. I’m having this problem. It’s horrible. I’m anywhere from .2 to .8 of an entire point discrepancy with the fingerbprick value always higher. It seems to be getting worse with time.

    I have a standing order at our local hospital for what I call Vein value draws, or IV draws. When I get a new bearch in a always double check strips. I take coagucheck xs with me to lab so I only have a five min difference between tests.

    I had my treating neurologist appointment yesterday. He said there is always a 30% difference in Coumadin values within the body. Apparently it’s just a very labile business, and that’s not even an APS patient!

    I’ve learned to just go for a draw depending on how I feel. ( but there is a lag. I can be low one day but not be symptomatic with migraine until the next day... morning- then clot two days after that. The larger clots. )

    Here was my neurologist’s solution:

    He ordered a Heparin lock and a 7 day daily INR study. He wants a week snap shot. ( Heparin lock because I’m scarring so badly in vein.)

    I tried to explain it might be a good week, there’s no guarantee it’s an accurate “snapshot.”

    He said, “ got a better idea? We gotta do SOMETHING!”

    ( this is because I’m having continuing small strokes to eyes ).

  • Hi Kelly,

    Have I understood it right: You take a Heparin-shot during 7 days and no Warfarin during that week and a Coagu-Chek XS-test also every day.

    Heparin-amount compared with your usual Warfarin-amount?


  • Sorry, I just saw this. No, you did understand right. “Heparin lock”

    He should have ordered in a PICC line. He made a mistake- he’s trying to save my vein from “ blowing “ from too many sticks 7?days in a row. I have a lot of scar tissue. He wasn’t to do a “ double test” for 7 straight days.

  • This is my experience also. I'm triple positive and la. When I first got the machine I would bring it to the lab twice a week and have the finger test and vein draw within moments of each other. They were always way off, more than 1.0 off, and we're sometimes high and sometimes low. So in the end I didn't keep the machine since it didn't work well for my particular situation.

    I hope someone is working on perfecting the machine so it works for everybody.

    Could your puncture have been quite deep? Small on the outside but deeper on the inside? For me, punctures do seem to bleed more profusely.

  • Hi Tofino,

    So you did not get the same differences at all?

    When the INR is very high the difference is bigger and when the INR is not so high the difference is smaller. If yo do this several times you will notice that the difference is always the same as to the high or low INR.

    How do you manage your triple-positive when you do not selftest? LMWHeparin?


  • I know others have had this, and compare the readings from hospital and device each time to see if there are similar readings each time, including the points of difference, is there always such a difference between home, and clinic etc. Also some people are not suited to self testing, I would have a meeting with your main clinician and keep a diary of readings and dates, for both to see if a pattern emerges. MaryF

  • That's right, Kerstin, I did not get consistent differences. Unfortunately, the self test doesn't work for everyone, but I am glad that it works well for you. Anything to make our lives a bit easier and safer is great!

  • Tofino,

    It does not work for me either but with the backup from Doctors and coagulationclinic I manage if I do it often enough and with consistency as to eating and writing everything down each day. Also I have Fragmins-shots to take when the INR is too low.

    Sorry that you could not carry on with it as it makes our lives at least safier.


  • My situation is pretty similar to Kerstin, high target INR and self-test and self dose every other day with heparin if I fall below 3.0.

    I did have some problems a while back with the difference in numbers being way greater than before, 0.8 or more I think, and I did all sorts of cross checks with my machine, the surgery machine and lab all at the same time. The lab and surgery machine were within 0.1 and I was still further out with my machine. Spoke to Roche and my then consultant had a word with previous one and St T's and we looked at Ribaoxobam (or whatever its called). Thankfully things settled down because I was not a suitable candidate for the new drug, (my profile didn't match any of the current studies) and frankly I didn't want to come off warfarin.

    There are so many things that can affect a result and we decided that 'it was just one of those things' - has since been cross checked many times and as my new haemo said on the last one 'bang on' even though I expect a difference of 0.1 or 0.2 as quite acceptable.

    It is a little worrying at first, and such occasions need to be looked at - but hopefully there may be something getting in the way that you identify and then all can return to nornal.

  • How are things going?

  • Soso. I have an episode today, that’s what we call a certified thing that happens to me. I will be doing whatever and suddenly I get EXTREMELY dizzy and have but a few seconds before I fall. I voice texted my daughter I had my can and hand on table but was not able to keep hold of cane and felt as though the table moved back from me( it didn’t move it is very heavy) anyway my daughter ran from her room to help me but couldn’t get to me in time & I feel when she was just inches away from me! So I felll onto the ceramic tile hit pretty hard but as usual I did NOT let me head hit. Yeah, I’m gunna be filing that tomorrow! I hope things are going better for u!

  • Glad you’re ok, things are better, did you get my email?

  • Yes. Thank u. I also have or had an ASD and a PFO (2 types of holes in my heat) that I had surgically sealed In June of 2011. Turns out the implant that seals the holes has been causing some trouble in some people. I was looking up my newer symptoms and found that they have issued some major warnings on the implants causing curosion of heart tissue and scarring that can make major health problems and if is found it’s a very dangerous condition that requires surgery. I haven’t had mine checked since October of 2011. But unfortunately I have all the symptoms so I’m tryn to get into c a cardiologist to have some tests run. Of course the symptoms could be a different type of stroke so who knows. I try this week to get into dr see what they find. I will let I know when I find out if it’s the heart or the blood causing the problems. The symptoms from yesterday’s episode are some of the main symptoms but could also be a stroke. The fun never ends!!! Lol

    Have a great day!

  • Pray you’ll get to the problem of this, meanwhile move slowly and keep in the presence of others. Do you have an alarm of some sort in case you need an ambulance, etc?

  • I have a sound bomb it on a chain I wear around my neck it’s cute little blue thing and when I med. help I pull it and it makes a loud irritating sound like a smoke alarm but louder. It lets anyone in the house know I need assistance. It’s cool it has a clip so I could wear it on a belt loop or something but chain around my neck works best for me. It doesn’t call ambulance just anyone that is within hearing distance so they can come help me.

  • Hi again,

    So you think that eventually it is the heart-issue that makes you fall?

    Have you tested your INR after a fall? Was it high or low compared to the other tests?

    Take care!


  • My INR was 3.39 on Halloween and no I did not test again after I fell. I don’t know about the heart thing. I just know when I was searching the symptoms I found that they have been having trouble with the closure devises and my symptoms match. Still waiting to get in to cardiologist to get the echocardiogram done to see if we can see an erosion or holes between the chambers of the heart.

    I will make some calls tomorrow and see if I can get into a dr. To get tested. Could just be TIA’s or something unrelated. U know how so many symtoms overlap each other with different health issues. All I know is I am just getting worse I can’t get stabilized. No matter what i do and it’s getting to be a rather frustrating!

    Thank you for asking.

  • Rechecking the INR after a fall is probably a good idea. I will try that!

  • The sooner you are evaluated by your doctor the better, you certainly don’t want to have a stroke.....

  • I hope the lab you use is certified. Also you should have more strips than 12 every 3 months (was it so?). You need to test more often than once a week probably.

    I did a lot of doubletests when I started selftesting. My Hematologist and lab helped me with this. It is very important to write everything down as to this illness. Also our memory is not the best so ...... I do not remember how old you are. I am 73 and divorced and live alone and my daughters are grownup with their own families so I can not shout when I feel bad. We phone every day though.


  • I know when I was checking they kept a tight rein on how many strips I used. Added to the frustration for me... worrying not to mess up because may have been using the last strip and next batch had not arrived yet. It would be helpful in the US if we could buy them somewhere in a pinch. Unfortunately you can only get from the supplier through the mail 🙄

  • I am very furtunate to live in this country I have found out. If my Hematologist and Specialist find it is important for me to selftest very often they let me have the amount of strips I want. They can of course follow my tests and writing how I carry on with my INR and Warfarin and also shots. They agree that I have to do tests very often at home. I think they trust me also. Feels good really.

    I have told them I am on this site so they understand that I know what I am speaking of perhaps.

    Best wishes from Kerstin in Stockholm

  • I agree, you are!

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