Inrange Coagucheck wrong readings

[Kev667]

Hi all,

For the past couple of years my Coagucheck and venous readings are pretty much the same. I have venous tests every 3 weeks.

Today venous is 7.3 and Coagucheck (done 3 times ) is 3.2.

Have been using this batch for last 2 venous tests and has been accurate up to now.

Rang Roche but they just took my details saying someone may be in-touch

Has anyone experienced this before and can give advice ?

Have ordered new test strips but I won’t have them for several days as Dr is slow at prescriptions. Hospital has advised skipping 2 doses and doing venous in 4 days.

thanks

Kevin

[panda60]

Been self checking from 2008 with no problems but I had covid 2020 and my INR was very unstable and then turned out my machine was giving incorrect readings. So can’t use it at present.

Do you have your machine checked to see if readings correlate with clinic one? Mine always is. Never had any issues with test strips though apart from my CCG stopping prescribing.

[Hidden]

Maybe venous result is inaccurate?.....i would get another venous test done i think. My Coaguchek is 'calibrated' against venous results annually. If within 0.5 of each other that's ok apparently. Last year the first calibration test was 0.8 different so i sent the slide to Roche who ran tests and all ok.....

BBC

[Jumper99 in reply to Hidden]

Roche may have said that there’s nothing wrong with the strip but with a variance that high you can’t rely on the machines reading. Have you tried doing another calibration? Also a year between calibrations seems a long time, my Anticoag clinic insist on 6 months. It’s no trouble to do a check for me, I just add in an INR check when I go for other blood tests. It’s really important to check especially if you are LA positive.

[Kev667 in reply to Hidden]

thanks all for your advice. I took Mullio’s advice and had another venous test today at clinic. To recap yesterday my venous test was 7.3 and today 2.1 ! Seems to me my coagucheck was accurate all along and I think the lab made an error . I doubt I can drop 5.2points in 26hrs. Nurse couldn’t comment on whether she thought the lab made a mistake. Now I’m on the low inr side. Coagucheck also reads 2.1 today so pleased it appears to be accurate.

Thanks all very much for advice

[Kev667 in reply to Hidden]

thanks all for your advice. I took Mullio’s advice and had another venous test today at clinic. To recap yesterday my venous test was 7.3 and today 2.1 ! Seems to me my coagucheck was accurate all along and I think the lab made an error . I doubt I can drop 5.2points in 26hrs. Nurse couldn’t comment on whether she thought the lab made a mistake. Now I’m on the low inr side. Coagucheck also reads 2.1 today so pleased it appears to be accurate.Thanks all very much for advice

[Greenmil3]

Kevin

Your lucky I had to come off self resting afterv5 years as my finger prick tests had absolutely no relevance to venous. My suggestion would be to get the new strips do 5-6 comparative readings and see how you go. Fingers crossed it all comes out the same and you can continue us self testing

[snorkle272]

Roche had a problem with faulty results from bad test strips about 6 years ago. It took a lot of customer complaints and more than six months before Roche finally admitted the problem was with the test strips. Eventually the strips were pulled from the shelves, and if you returned your faulty test strips they were replaced. I don’t know where you live but I would check to see if there has been a recall on your numbered batch of strips. Good luck.

[Jumper99]

Are you triple positive? If not, have they continued to do aps tests to make sure? My haematologist has just rechecked all my tests as I was dual positive and he wanted to see if I had become triple positive. If you are triple positive you normally can’t rely on a home test. If you are LA positive you might have problems, APS Support UK says you need special rules like calibrating every 3 months I think, if you are LA positive.

[Kev667 in reply to Jumper99]

hi thanks for advice. I’m just LA. My Coagucheck is calibrated and always pretty accurate within 0.2 points.

I retested at clinic today and it’s 2.1 same as cogucheck.

I’m guessing yesterdays venous of 7.3 was an error at the lab and my Coagucheck was correct all along.

Doubt I can drop 5.2 points in 26hrs

Thanks

Kevin

[Ray46 in reply to Kev667]

Just out of interest, did you skip 2 doses as they advised?

[Kev667 in reply to Ray46]

only the one dose I skipped that evening . Both Roche and nurse said an error must have been made at the lab. Roche initially asked for my machine and strips back to test but rang me to say not necessary now. Had 2 venous tests since and within range and cogucheck is accurate. Nurse told me lab sometimes makes errors thankfully not often.

[MaryF Administrator]

A virus, or some new change in diet can all affect readings so important to check the difference between the machine and blood draw asap and to chase up your GP for your prescription, which I know is a drag, as they all seem pretty overworked currently. I hope things do settle down, and it was just a blip, let us know how you get on. MaryF

[Ageingfemale]

I’m LA positive and have kept a record of venous and self test results. Mine are always 0.8-1.0 difference so I count the self test as just a guide and have a venous every week or 2 weeks if low.