Serum or urine test results for CKD? - Early CKD Support

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Serum or urine test results for CKD?


How can you judge progress with CKD if there appears to be conflict between serum and urine test results?

My mum has CKD stage 3 and had a cancerous kidney removed 3 years ago. Whilst her serum eGFR and creatinine results since then have been slowly improving (eGFR reached 61 ml/min 9 months ago and creatinine now down to 98 umol/l), urine tests a few days ago indicate the opposite. For example, her urine microalbumin has steadily risen to 43.3 ug/ml so is classified as abnormal.

Ive researched a few websites and they all indicate that both serum and urine results should be considered in combination eg: " combination of specific tests now called the Kidney Profile. When performed together, these tests—a urine sample for albumin-to-creatinine ratio (ACR) and a blood test for estimated glomerular filtration rate (eGFR)" But how is that possible if they indicate opposites?

She will ask her nephrologist when she sees him in ~2 weeks but hopefully you intelligent people can explain via knowledge and/or experience. Also she is not confident about her nephrologist, partly because he didnt raised urine results with her last year (abnormal/out of range then) and because he seems more focused on her cholestrol levels than her kidney results (my separate post yesterday in Kidney Disease section)

28 Replies

It is wise to ask the nephrologist about the differing in results. If the eGFR and Urine Albumin not given at same time, it might be possible reason why difference.

userotc in reply to orangecity41

Thanks. She will indeed ask nephrologist despite lack of confidence in him.

The latest eGFR was measured approx 2-3 weeks before the urine albumin. I can't imagine that's a significant time difference to explain the difference.

But, more important/relevant are the trends over the past 3y. We examine plots over time (on Patient Access) and serum results have gradually improved over that time period whilst the urine results have gradually worsened.

orangecity41 in reply to userotc

Link to information on eGFR, ACR and BUN tests.

userotc in reply to orangecity41

Thanks for the link but I dont understand if/how this explains the anomaly between my mum's serum and urine test results? Please clarify, if so.

In case Ive been unclear, Ive quantified the changes in last 3years (since soon after her nephrectomy) below for the parameters you linked and my understanding of progress that the data indicate:

sCr: ~25% reduction down to 98 umol/L (N= 40-95). Positive progress

eGFR: ~50% increase up to 53 ml/min (N >60). Positive progress

Blood Urea: steady at ~12 mmol/L (N= 2.5 - 7.8) No decline. NB Not shown as BUN

ACR: ~3000% increase to 8.97 mg/mmol (N= 0 - 3.5) Negative progress

orangecity41 in reply to userotc

Sorry I am unable to clarify. We are not able to diagnose on this forum either. Best you get her Doctor to explain the reason for the test results.

userotc in reply to orangecity41

Sorry I wasnt expecting a diagnosis but any relevant experiences so that mum can consider in preparation of her nephrologist appointment. Ive researched quite a bit in past couple of days and there are some potential reasons for the discrepancy between serum and urine results so she can consider those, in advance.

Bet117 in reply to userotc

Good afternoon, userotc,

I can understand your concern for Mum and confusion by her kidney disease and test results.

Be it in the UK or US, the patient's doctor/ consultant should be the first line of communication when there are questions and doubts. Consultants are professionals who are trained and qualified to explain lab results and set a plan to treat each individual patient.

To put your mind at ease and go forward, I would ring up and make an appointment to see the GP or Consultant who ordered these labs and go in to see him/ her.

I would print out a copy of Mum's labs and check off any results which flag high or low next to the printed lab ranges. Write down any questions and concerns that both you and Mum may have. I note things on the lab sheets and also bring a small notebook with me to keep a record of Blood Pressure, weight etc. as well as discussion during the appointment.

I would also discuss what health plan; including diet, medications etc. they recommend for Mum's particular case.

If you and Mum lack confidence in that particular consultant, look into making an appointment with another you are comfortable with. You and Mum might want to discuss your feelings with her GP and ask for help and a referral to someone else.

The folks here are delighted to support you as you go through this journey with Mum, but recommend that the doctor/ consultant be the one to explain her condition and tests.

Ring the consultant possibly the GP and go in.


userotc in reply to Bet117

Thanks Bet.

Particularly in light of covid restrictions (which may limit appointment attendees), we want to ensure mum is well prepared before seeing her nephrologist - as I mentioned earlier, she has an appointment soon. Certainly if my dad can also attend, she will have support and he would prepare thoroughly and have relevant test results, trends etc with him. I will ensure that.

We already have some relevant intelligence via online research but personal, anecdotal experiences wouldve been a bonus.

Unfortunately the support of her nephrologist has been underwhelming to-date (no diet advice etc) - so much so that she is considering changing, if possible.

Bet117 in reply to userotc

Hi userotc,

I think that having your Dad accompany Mum to the appointment, if possible, is a fabulous idea. I know that here the covid has yielded restrictions as to family attending as well, I would ring up and check; stressing that it would be in Mum's best interest to have Dad there to hear what is said. If she is elderly, even more.I would stress that at this point.

Remember to buy a notebook to note vitals taken, discussion and to note questions.

Rather than base questions and discussion on information that you have read on the internet, base your questions on the labs that are in front of you. I can't stress enough to you to check off any labs which you see as flags and any that you want the consultant to explain. It is their job and the taxes are paying them good money to do so. Diet is critical with kidney patients, so I would stress to your parents that it is important to bring it up at the appointment. Many do not bring it up, so you ask. You can also ring up her GP and ask his/ her opinion as well.

My friend from the UK was given food suggestions by both her GP and consultant as I don't believe a dietician was available. Most importantly, labs and medications are explained, and a treatment plan is set.

If this consultant is not willing to listen to Mum, participate in a discussion and answer questions in terms which are easy to understand, then I most certainly would ask her GP to recommend someone else.

Parents are special people; you are a wonderful son to do as you are for Mum. This will get straightened out, it takes time.

Please reach out and do let me know what the outcome is.

Warm thoughts ..


userotc in reply to Bet117

Many thanks Bet for your warm comments and advice.

For your update, my Mum yesterday requested by email that the appointment is now scheduled as a videoconference (or similar) on the basis that she is growing concerned about covid and to ensure Dad's participation.

This also has the benefit that her test results can be easily downloaded during the conference, for discussion. Similarly a Diet Plan that I have proposed, for discussion etc. She thinks it may even help improve communication (her nephrologist is not English) and reduce his previous emphasis on statins! So hopefully it will be agreed.

I will try to keep you posted.

Bet117 in reply to userotc

Hi userotc,

Gosh, no thanks ever needed!

Actually, a video conference may work well for you at this time as you can all be on the computer or cell phone and hear what the consultant has to say.

If you have a patient portal and can print out a copy of your labs as I suggested, do so. I know that you have Mum's labs as you initially posted them. Check off labs in question and note any questions prior to the appointment. Make sure that she doesn't sign off without all of her questions answered.

Have the consultant explain Mum's creatinine, GFR and BUN levels to her. Additionally, her protein, albumin, albumin to creatine ratio as to see if she is spilling protein into her urine. I would also review electrolytes such as sodium, potassium, and phosphorous which are important to kidney patients. Have her ask about her iron levels, calcium, vitamin D and also complete blood count. All important. Ask her glucose level as diabetes, high blood pressure and elevated cholesterol are also common with kidney patients, which is why statin drugs have been discussed.

As far as diet, best to check with Mum's doctor as each person is different .Generally kidney patients eat a low sodium ( 1500- 2000mg per day) low protein diet which is based on chicken, fish, eggs and no red meat. If her doctor feels that her labs are good, beans and hummus are also good protein. Avoid processed foods, bacon, cold cuts and hot dogs as they are high in sodium. A diet rich in fresh and fresh frozen vegetables such as cauliflower, onion, peppers. Parsnips, cabbage is great. Steam, grill or roast with spices and a tad of olive oil. Salad is also good with vegetables, but eliminate tomato unless the doctor says so as it along with potatoes are high in potassium. Eat light wheat bread, pasta, oatmeal or cream of wheat porridge and watch dairy consumption. Avoid dark colas, NASID pain medications such as Advil or Motrin and Aspirin and drink lots of water.

Remember that each person is different and your Mum's doctor should be her first line of communication. Monitoring labs are very important. At 64, she is far from old! Just remember that this is a process which takes time to put in place. Your goal is to prevent progression.

Below are a couple of interesting links which may be of help.

Do keep in touch and let me know how you are all doing. Stay safe.


userotc in reply to Bet117

Hi Bet.

Thanks for the detail. I suspect the test of the value of mum's nephrologist is if/how he reacts to her latest test results. Using your words, she has been "spilling protein into her urine" for the past year. He didnt even comment on urine results at last year's consultation when, for example, her urine albumin:creatinine ration was over-range (4.68 mg/mmol) so let's see what he says now it is 8.97 with albumin having increased (to figure quoted in earlier post) and creatinine decreasing. I suspect he may request 24h tests at least (though her GP may after requesting urine repeats).

Maybe the urine changes are not as bad as many with CKD (?) or maybe he is only interested in serum data which are holding up. But our focus now is to improve them both asap via even stricter diet and wellbeing. Hopefully the urine results will start to improve before the retest before she sees the nephrologist on 6/11.

PS I am concerned that her current nephrologist specialises in transplants!

userotc in reply to Bet117

By the way, mum is a sprightly 64!!

serum creatinine testing is a joke. I have literally had two blood tests taken by two labs 15 minutes apart and gotten massively different results. The first indicated I had normal creatine, the second 15 minutes later indicated I have stage 3 CKD.

userotc in reply to MattKansas

But what is better?

There can also be errors with urine due to UTIs (mum has her share), diet etc. And no damage is reported from her annual CT scans.

My understanding from research is that medics rely on serum results mainly.

MattKansas in reply to userotc

They have better tests, specifically serum Cystatin-C. Cystatin-C is not as effected by things like muscle mass, diet, exercise, etc. I'm not sure why they are still using creatinine at all, my guess is it is cheaper.

Hopefully I can add something to your concerns since I too had my cancerous kidney removed, in 2017. First of all your mother is doing outstanding. Using the standards or measurement we use in the USA, your mothers Creatinine level is about 1.1. mg/dl. (you measure is at 98 umol/l. Now the normal range for a person with TWO kidneys is up to 1.21. Some labs use a different scale and normal can be reported as less than 1.5. In either case your mother is well within normal range. MOST people with one kidney get much higher "normal" ranges of between 1.7 and 1.9. This happens mostly in a bit older people because the remaining kidney does not respond to the additional "workload". Whereas in younger people he remaining kidney filters can expand as much as 50% and compensate for the removed kidney. Bottom line your mother's kidney is doing GREAT regarding creatinine. I have been consistently between 1.6 and 1.7 Creatinine and my doctors are totally satisfied with that. Look at this link and you will see it highlighted in yellow that normal creatinine levels for one kidney are 1.8 to 1.9. So be very happy with your mothers results.

Now lets talk about her egfr. You say she is stage 3. But don't get all caught up in the egfr stuff. This formula is highly criticized especially at lower stages. Think of it. In a blood test the normal range is below 60. Yet this same person is labelled as Stage 3??? Again think of it, a normal Creatinine like your mother is "1.5" or below, Creatinine is a key ingredient in the determination of egfr, yet your mother with normal Creatinine is called diseased and at stage 3?? I see 5 different doctors. Kidney, heart, cancer, primary care, urologist. They ALL, even the kidney doctor, say don't pay much attention the egfr stuff. The key things to follow are that you have a consistent Creatinine level over time, and no protein in the urine. That is NOT to say that egfr is worthless. But keep in mind what stage 3 means. MODERATE kidney illness. Well what do you expect from a person with one kidney?? EGFR does NOT take into consideration practical factors such as the fact your mother only has one kidney. What medications she may be taking that effect Creatinine levels, her physical condition (the same formula is used on a person who is weak and ill at a particular age, as one that is healthy and energetic at that same age), and other illnesses (such as diabetes, or cancer).

You Mom is doing great. A person with one kidney it TYPICALLY, lets say normally, never going to be in the "above 60" category, unless a youth or young adult. Just monitor Creatinine. And look for consistency.

Now the microalbumin levels. It is measured differently in your country than here in the United States (different units of measurement). You used ug/ml. Now your mothers is slightly above "normal". Yes kidney problems can be a cause, but as you say your mothers Creatinine level is fine. But there are many other factors that can cause increased albumin. Blood in urine due to a urinary tract infection, or kidney stone, etc. Recent exercise before the test. Different medications. The best practice is to take a second test and see if things are more in the normal range. You are assuming that the only cause can be kidney related. Not the case. Especially if her other kidney measurements are constant and in fact improved.

PLEASE remember you are charting and comparing to ranges that do NOT NOT NOT take into account that a person has one kidney. one kidney is NOT normal. If it were normal we wouldn't have two in the first place.

userotc in reply to RickHow

Hi Rick. Thanks for your reassuring comments and I'm sure you understand if Im over-concerned about mum. Just a couple of points:

1. In your 2nd para, you say it's key to have no protein in the urine. Are you referring to albumin or total protein or either/both?

You know her microalbumin is abnormal. Her total protein is now 0.09g/l but no Normal range is given nor abnormal alert so does that mean OK according to medics? It was actually higher 9 years ago at 0.11 (no alert) - she was classed as CKD 3a then, with 2 kidneys.

2. Re microalbumin false positives caused by blood in urine etc, I have certainly read that on the internet and mum has indeed always had some blood in her urine. But I've also read a report from Brazil which indicates urine markers can precede serum for kidney disease. Hence my concern there.

Also could/would urine creatinine reduce with false positives? The reducing trend for mum's in the past 3y is the exact inverse of her increasing microalbumin over that period.

Anyhow a retest is arranged for next week.

Apologies if I'm over-analysing but I'm quite new to CKD issues.

Thanks again.

Where to begin? :).

First I think you and I have been talking a little bit about different testing. All my numbers refer to testing of Creatinine in the BLOOD test, not a test of Urine Creatinine. When I speak of protein (which is what I was talking about), I was speaking of protein in urine. That is one of the keys my doctors monitor (protein, not albumin). Creatinine (in blood) remaining stable, and no PROTEIN in urine, are the top factors (not the only) they use to monitor my kidney function. Now when I say no protein I am referring to the urine measurement that , as you say, is simply reported as NEGATIVE (no number given). Everyone has some degree of protein in their urine, but with CKD it is key to have the measurement be reported as NEGATIVE (which means really, normal, just trace amounts found).

So where does this leave you. Well frankly you sound exactly like me from the time my kidney was removed, and for about the first year of being labelled "CKD". I read every article, every post, every study. I plotted and charted every aspect of my blood and urine tests over time, even tracking levels of items that I did not understand such as lymphocytes, etc. Then I reached the realization that while a base understanding of CKD, items measured, is a must, that you really are doing nothing except causing yourself undo stress. That if for example, I go for a blood test today, and my blood Creatinine is way too high, or this item or that item is way out of range, that it is what it is. That all my plotting and reading and worry, did nothing to prevent it. That I just wasted hours and hours and hours of worry, reading, charting, depressing myself, and it made no difference. That those valuable hours could have been spent on making my life (no matter how long or short it will be) happy. That in most cases (other than common sense diet, exercise, etc., etc., ) there is no magic pill, or short, or medicine, that is going to change my "ckd". I try instead to think of more encouraging things such as only about 1 in 50 people enter end stage renal disease, that are currently at a moderate level of kidney disease. That in actuality most people with "ckd" actually die from cardiovascular events than from kidney failure.

Now regarding your mother. You have tracked and found something that bothers you (the different courses of your mothers creatinine versus microalbumin levels). Worthy of a question to your doctor. But let say (and hope not) this is some kind of reflection of her "cdk" (which personally I doubt given that her creatinine levels are improving), it is not an emergency situation. Because unless it is caused by perhaps her medication, or a sign of onset of some level of diabetes (which affects microalbumin levels), or kidney stone, etc., there is nothing a doctor can give you to change it.

My advice. Stop reading every article you can get your hands on (such as some obscure study done by a doctor in Brazil). On the internet you can find a study to contradict any conclusion made by another study. The fact is all these studies, none of them has found a way to stop "ckd", cure "ckd", or made any breakthrough treatments. Knowledge is power, but too much knowledge about something you have limited control over, provides you no benefit.

Next appointment just ask the doctor why is one going down and one going up, and more than likely he/she will give you that blank doctor stare.

Last word of advice. When my kidney was removed due to a large tumor in the center of the kidney, it was cancerous. It was totally encapsulated. There was not surrounding cancer in the nodes. All the doctors said I had less than a 3% change that the cancer would return. Some said less than 1% chance. Well about one year later it was found that the cancer had returned. It had eaten away huge amounts of two vertebrae in my spine. I had a large tumor in my right femur near the hip, two other tumors in my pelvis, one more tumor in my 3rd rib.

All discovered by a coincidental CT scan. I had no pain, no knowledge this was happening in my body. I underwent 3 different rounds of radiation (10 days each), a hip replacement to remove the tumor, a spine operation to have rods put into my spine because there was almost nothing left of the two vertebrae. There is no chemotherapy for metastatic kidney cancer. I get IV immunotherapy every 3 weeks, but this generally only works for a very few months. the bottom line of my story? All the days and nights of worrying, plotting, reading, about my protein being one tenth of a point being too high or lower, or my Creatinine one time being above my normal, etc., etc., made no difference in my life. Here I am over 3 years after I was labelled as "ckd" because I had a kidney removed, and my kidney function is about the same as it was then (sometimes better, sometimes worse). Don't be too obsessed about it all, because in the end, you have only limited control anyway. Be sure to have your mother tested (scanned) at least every 6 months, for cancer coming back.

userotc in reply to RickHow

I shouldve added at the end of my 2nd paragraph that my analysing of serum v urine effectively gives a reason to deflect further proposals for statins at present.

Thanks Rick. Sorry for what you've been through, mum now scanned annually.

To be honest, my main reasons for analysing is to know more so we can respond intellegently to what her nephrologist & GP say. So far its been keep doing what you're doing (which you seem to agree with as ref serum results) and take statins. Mum doesn't want statins so that becomes the main reason for knowing more.

We will have questions ready for the imminent consultation and hope to be able to ask and get replies.

Take care.

RickHow in reply to userotc

I have taken statins for approximately the past 8 or 9 years. There is much debate on the effect on people with "ckd". I take them because my cholesterol levels were high and not controlled by dietary changes. I take 80 mg (highest dose) of Atorvastatin. I'm taking them mostly to reduce the risk of cardiovascular problems. You see, the majority of deaths for people with CKD does not occur from renal failure. Rather it is from cardiovascular events. So to me the choice is simple. Without taking a statin I am risking cardio problems due to elevated cholesterol in my cardio system which is in trouble due to high bp. (and this causes problems for a kidney). So, the question is to not take them and it may (and I stress may) be a little better for the kidney, and then have cardio problems, OR to take them and help my cardio system (the leading cause of death of people with CKD) but potentially (but not proven) harm the kidney somewhat. AND taking a statin does help to reduce protein in the urine.

We've researched quite a bit on statins and, let's just say, the jury is out with many reputable sites disputing their benefits for CVD.

My dad tried them for 9mths then decided to stop. He also noticed a doubling of his billirubin which even the GP later admitted was probably caused by the statins. When he mentioned that to mum's nephrologist who was vehemently proposing statins for her, the nephrologist said "yes they can damage the liver"! So I understand why mum has refused them to-date.

Sorry you were unable to control cholestrol naturally. In replying to a separate post I sent on the Kidney Disease section of HU, a CKD patient said she'd managed to reduce hers by ~33% (from ~9 to 6) with improved diet. Mum will seek to do something similar (latest fig 7.4).

We realise mum's medics are likely proposing statins because of CVD risk. In response, she requested further, relevant investigations eg LDL particle test. Thus far the reply is silence!.

Ideally we will discover the reason why mum's cholestrol has increased - CKD being 1 option - rather than suppress it's level.

RickHow in reply to userotc

I think you probably read this article (I send you the link). About cholesterol and relationship with CKD. Every person on this website must make their own personal decision about what to do, what to take, what to eat, etc. I draw your attention mostly to the closing paragraphs of the article.

My decision is that the benefits of taking the statin far outweigh the "negative" effects. As you say possible harm to liver is a side effect. But it is VERY rare. And it is easily monitored with blood testing (which I receive every 3 weeks) so first sign of harm it could be stopped. Luckily so far, there has been no ill side effects, of any type, over the years I have taken the drug. The famed Mayo clinic has posted a page on "should I take statins or not". Perhaps you have seen it. But I send you the link. I tried dietary changes first. But the lowering of my cholesterol was minimal. Both my gp and cardiologist insisted I take it. One other point. My triglycerides were extremely high. Very. Statin had no effect. I tried diet, exercise. nothing worked. Then I got a new cardiologist. He believes most firmly in the less medications the better. So he said, just purchase over the counter Niacin tablets. Take an average dose. I did. Within a month my triglycerides dropped tremendously. First time in my life that not only were they in the normal range, but in the lower portion of normal. But he too insisted on the statin. Best of luck in your decisions and mother's health.

oceansplash in reply to RickHow

Hi, Rick. Thanks for the great info! Do you have any thoughts on how to reduce heavy proteinuria?

Thanks Rick. I have seen those links before along with many others stating the opposite (but I dont think there's much point exchanging further links). Hence why I referred to disputed benefits of statins for CVD in my previous post.

However, I think we have some common ground eg from the daVita link you sent: "keeping track of your cholesterol levels and eating certain foods may help treat or prevent inflammation". Both of us want to reduce any inflammation - and hence cholestrol - although I think we differ insofar as I believe that the cholestrol signals a problem that needs to be addressed rather than causes it.

Thanks for your wishes and best of luck with your own treatments and health.

Thanks for the great conversation with Rick. Didn't address my "Heavy" proteinuria, but very good advice especially because I'm super stressed all the time over this stuff. One kidney, stage 3, heavy proteinuria.

Glad you enjoyed it! Not sure what protein level you mean with "heavy" but mum's latest total is 0.09g/l with albumin 43.3ug/ml.Nephro unconcerned at those levels despite increasing trend in past 3y or so. But we are seeking to reduce or at least stabilise.

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