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Kidney function test

Sambaqui profile image
30 Replies

Like a great number of us on the site, I take a daily anti-coagulant. Next week I have a blood test for kidney and liver function and am curious to know more about how I might understand the results. Can anyone tell me how to read the figures that come back - what signifies healthy functioning or otherwise? My GP is likely (and hopefully) to say "normal" but I would like to have a bit more detail. Thanks, if you can help.

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Sambaqui
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30 Replies
BobD profile image
BobDVolunteer

I always think it best to accept "normal" rather than question as normal is a moving target. As we get older kidney funtion usually drops so if one is so determined to understand the actual numbers then you need to see a trend over time rather than one result. That is my understanding anyway.

Sambaqui profile image
Sambaqui in reply to BobD

Thanks for your reassurance, Bob. I had to remind my GP that it had been well over a year since I had a kidney test and this made me a bit insecure as to whether I was being monitored at all. "Normal" always seems such a vague way to describe bits of our body, though I guess "abnormal" would not be welcome.

BobD profile image
BobDVolunteer in reply to Sambaqui

Forgot to say, top marks for calling it an anticoagulant and not -----thinners.

Adasian profile image
Adasian in reply to Sambaqui

I have Hashimoto thyroiditis. In one of my tests my T4 was just a little high but my T3 had dropped from what was normal for me. My GP wanted to lower my thyroid meds but I was concerned at the time as I was experiencing tiredness and fatigue. I also asked for a Reverse T3 test which naturopathic doctors believe is an indicator as to why this is happening but not GPS. You can Goggle it for symptoms. Turned out however, after wearing a heart monitor they discovered that it was AFIB. Anyway she sent me to a Thyroid specialist who Kept me on the same dose of meds for a year.

My doctor just lowered it, as she wanted to do from the beginning and it has been over 4 months and I feel fine. Wonder if that triggered my persistent Afib which I have though? Good to stay on top of your meds .

brit1 profile image
brit1 in reply to Adasian

my first af was triggered by a stupid dr overdosing my thyroid meds for my low thyroid which sent me into hyPERthyroid and AF 11yrs ago. Now I have to keep a close eye on my thyroid tests every 6mths

Auriculaire profile image
Auriculaire in reply to BobD

I accepted "normal" from my GP for a thyroid test I had in 1993. After 7 more years of suffering the debilitating symptoms of hypothyroidism ( including a stone and a half of weight that I have never been able to shift despite at the time eating healthily and taking lots of exercise) I was diagnosed after a hospital blood test. When later I asked to see the results of the earlier blood test and having done a bit of research on the thyroid I found it was not in fact normal. The TSH was just over the top of the normal range but the free T4 was well below. This latter figure SHOULD have been a red flag to my GP necessitating more testing at 6 month intervals. I would never accept "normal" now but would want to see the figures. Luckily here in France your blood test results are always sent to you the next day and if there is anything that is out of the "normal" range you can see it for yourself and ask the doctor about it . I have routine blood tests going back to 2002 ( kidney and liver function included) so I know what is normal for me. It could well be that with age some things have declined a bit but that too can be seen. Unfortunately hypothyroidism is another condition that many GPs know little about.

Adasian profile image
Adasian in reply to Auriculaire

Agree! Thanks

Finvola profile image
Finvola

When my printouts come back, each component figure is listed with the normal range in brackets and anything outside this is highlighted and if not satisfactory, is referred for a doctor’s scrutiny.

I know where you are coming from, I’m curious too and always have a look to try and understand.

Sambaqui profile image
Sambaqui in reply to Finvola

I shall ask for a print-out of results and, hopefully, now have some sense of what the figures refer to. Thanks, Finvola. Why do people say "curiosity killed the cat" when it's often the only thing that saves us?

Auriculaire profile image
Auriculaire in reply to Sambaqui

One of the many sayings that is meant to keep people in their place and not questioning authority . "Too clever by half" is another. Interestingly there seems to be no French equivalent of the latter.

Cat04 profile image
Cat04 in reply to Finvola

I ask for a print out too, I like to know where I stand and then compare results with subsequent test results to see which way I'm going!

Sambaqui profile image
Sambaqui

Thanks for your response, HappyJo, and the link that helps me understand "normal". Like you, I don't like hearing generalisations without having some idea of what it is being spoken about. Also, there have been more than one occasion when medical results or follow-ups have got lost in the system or expected tests have not materialised, all of which makes me inclined to want to keep an eye on things. So I think it's right to ask questions and try to understand, while trying not to pester my GP too much.

baba profile image
baba

Always ask for a copy of your results with ranges. Keep your own records and observe trends. If anything is out of range ask for an explanation.

I have been told "normal" when my thyroid function was NOT normal.

Sambaqui profile image
Sambaqui in reply to baba

Yes, baba, it's good to know others also feel the need to have the information. Normal is not always reality. Thanks.

MarkS profile image
MarkS

The kidney function test is measured by "egfr" (estimated glomerular filtration rate) which if above 60 is normal, 30-60 impaired and <30 significantly impaired/end stage renal failure. The egfr reading is reduced when you have AF, and is also reduced if you exercise a lot (higher creatanine due to muscle breakdown). Before my ablation 10 years ago, it was 55-58. Since my ablation it has increased to 65-70. It is only an estimate but a useful indicator if more tests are required.

Sambaqui profile image
Sambaqui in reply to MarkS

Thanks very much, Mark. That's really clear. Just what what I wanted to know.

MydogBrandy profile image
MydogBrandy in reply to MarkS

Hi my Colin had one of his kidneys out last year because of cancer and has just had a blood test ...done in the garden because he is shielding...they said it had increased from 198 to 201 these seem awfully different to you figures are they measuring something else then? Any suggestions gratefully received

MarkS profile image
MarkS in reply to MydogBrandy

It's possible it could be creatinine, usually a max of 115. Otherwise a cancer measurement?

MydogBrandy profile image
MydogBrandy in reply to MarkS

Thanks for your quick reply. I don’t know . Because we are shielding his appointment is cancelled. He should have had a scan. The scan he has takes about 6 hours because they have to put fluid into him first via a drip. They have told Colin now that he must tell the nurse that they must not put the blue dye in next time!!! You just put your trust in them but one wonders why it wasn’t put on his notes NOT to use the blue dye. I am obviously worried but as we can’t go anywhere the mind goes crazy.

Colin also has some cancer spots on his head which need removing but this has also been put back because of the virus😥

secondtry profile image
secondtry

Agree with Bob, the trend is the important thing and it is never to late to start recording your annual tests. I suggest you request the actual result not just e.g. >90 as the only way to monitor trends.

Sambaqui profile image
Sambaqui in reply to secondtry

I shall do so. Thank you.

Palpman profile image
Palpman

Twice now my GP has glanced over my test results and said all is ok.

Now that I have access to my tests on the NHS app things look very different.

My bilirubin is so much higher than normal.

My CRP is indicating that my body tissue is more inflamed with tumors than it has normal tissue.

My blood viscosity is so high it must be like syrup.

Why she never mentioned these is beyond me as the aim was to look for reasons for breathlessness and arrhythmias. These tests are 9 months old.

Sambaqui profile image
Sambaqui in reply to Palpman

I do not know of the NHS app. Does this show readings of all and any tests carried out by the NHS? And is it available to anyone?

Palpman profile image
Palpman in reply to Sambaqui

Download it from playstore and register. Have your passport or other ID on hand.

The test results may not show up if your sutgery has not enabled it. I had it enabled with the "contact my surgery" button but this seems to have been removed temporarily.

Alternatively contact your surgery receptionist to enable it.

Sambaqui profile image
Sambaqui in reply to Palpman

Thanks very much, Palpman. I shall check it out!

Auriculaire profile image
Auriculaire in reply to Palpman

Probably she does not want to spend the surgery's budget investigating why you have these abnormal blood results. My GP explained to me that ESR ( another inflammation marker ) does rise steadily with age and the normal range is a reflection of values for younger people. But a very high CPR should really be further investigated.

Palpman profile image
Palpman in reply to Auriculaire

My CRP is 121 while the maximum should be under 5.

This is not due to age.

Auriculaire profile image
Auriculaire in reply to Palpman

No ,I think that should be investigated.

Mister_K profile image
Mister_K

Go here:

labtestsonline.org/tests/bl...

The site will explain all you need to know... Mainly your BUN and creatinine results are the starting point to assess kidney function. Make sure you also get a urinalysis. If kidney function comes back suspicious, you can also request a CCL (creatinine clearance) and CT scan. Some anti-coagulants are actually eliminated by the liver. If you're taking warfarin, for example, check your liver function as well.

MarthaJ profile image
MarthaJ

Hi, personally I never just accept 'normal' but ask for copies of any blood test results so I can check for myself and if necessary query them with GP or do further research. Past experience has shown that GPs do make mistakes and sometimes gloss over 'near-normal' results so I think we have a responsibility to ourselves to double check. More specifically I find I have to ask for repeat tests for kidney function as they are not offered on a regular basis. When I was first put onto medication for BP, the consultant said I should have regular blood tests to monitor the kidneys but GP at the time said simply 'I don't do that'. After years of being told kidney function was normal I was suddenly telephoned last year by a new GP to tell me I had stage 3 chronic kidney disease but it was 'nothing to worry about' and also, when I asked, that there was nothing I needed to change in terms of lifestyle, diet etc, although I had not been asked about either! Since then I have requested repeat tests as I don't want to be relying on a single annual test to monitor this.

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