Newly diagnosed w/CKD questions

Hi. I hope you can help. I have a relative who is newly diagnosed w/CKD Stage 3. I want to be able to help her, so I have several questions, if you don’t mind. She didn’t even know she was in Stage 1 & 2, so she’s in a state of shock! Her eGFR is 50 & her potassium is 5.3. Her doctor told her to lower her potassium. She is taking a potassium-sparing ACE inhibitor (lisinopril) which is keeping her blood pressure under control. If she drinks more water and if she works out to the point of sweating, would that help lower her potassium or would that drug still cause her to retain the potassium? Also, she was told that ACE inhibitors help protect the kidneys, so if she was already taking this drug, how did this CKD happen? What if she got the doctor to switch her to a diuretic blood pressure medicine? She knows that she needs to watch her diet now, but is finding that very difficult because many of the fruits & vegetables contain high potassium. She does have a list of low-potassium foods, but that is very limited. How much potassium can she consume daily to still be in the safe zone? If you can answer these questions & give some guidance, she would be very appreciative because her next doctor’s appointment isn’t until 2 more months & she wants to be proactive about keeping this condition under control. Thanks very much for any advice you can provide!

I am sure Dr. Agar will have a very thorough response, but he most likely will need some more specific information such as age, weight, medications, how long she has been on the ACE inh (it can cause elevated crt levels all by itself as well as the potassium issue), other medical conditions, family history of renal disease, US results if done, urinalysis results if done, etc. It is a complex question which in reality requires a very thorough evaluation since renal disease can present in so many different manners. You didn’t state whether she has seen a nephrologist but at stage 3, that might be the best place to start to fully elucidate the underlying condition that is causing the elevated crt levels as well as the potassium issue alone which is from an internists perspective is one of the most difficult detective stories to search out in modern medicine. The issue of lowering potassium with diuretics is a good one to consider but depending on the underlying cause of the renal insufficiency, they can at times worsen the condition. I look forward to reading Dr. Agar’s approach to this issue especially the potassium issue, but I suspect that the amount of data presented so far will limit his response to any specific recommendations for her medical team to consider.

Dear joecool1007

The first thing I would say is that, as Peter Laird has already written, there really is too little information to be able to be too specific … and I must also note that this site is not designed for, nor should I give, specific or direct advice to individuals … that would be neither wise nor appropriate as direct, specific advice needs detailed, on-the-spot clinical information that is only available to the caring physician.

The Internet is not the place to give – nor to receive- detailed and individual advice. Those who try to give or who seek to receive such advice place each other at risk.

Furthermore, this site is primarily designed to help those ON OR APPROACHING DIALYSIS … not those in the earlier stages of CKD.

That said, I will break the site boundaries, just this once, to make some general observations about CKD – some of which may help you.

Firstly, Stage 3 -5 chronic kidney disease (CKD) is common. Yes … to find out that one has stage 3 (or worse) CKD is always confronting, frightening and comes as ‘a shock’ – as you put it. This is usually made worse by the fact that it is commonly discovered almost by accident – kidney disease being, as it is, largely symptomless and discovered ‘en passant’.

However, CKD is much more common than you might think. Though estimates vary, from country to country, CKD3+ affects >1 in 7 adults (Australian data … and US data is even more stark), and most of these do not know they have a problem. Diabetics, smokers, people >50 and indigenous populations are chiefly at risk.

Your post does not state her age, her other medical history (if any), whether she is diabetic (a hunch she is), her family history, her laboratory findings, her urine and imaging details or even the cause of her CKD. As Peter Laird has rightly said, there are so many other bits of data missing and which, no matter how meticulous you are on the Internet, cannot be supplied though this forum.

The first observation is her eGFR of 50. Here, her age is important. Though I imagine she is young (you said she could ‘work out to the point of sweating’ – which implies a measure of youth), older people may have and sustain for years and years a low(ish) eGFR without there being any significant risk or implication of progressive kidney disease. We humans tend to age … it’s a fact of life – and typing these responses often late into the evening at home reminds me of this! … and as we age, we lose renal function and functional ‘flexibility’. Just like you can look at an older person and guess their age from how they look, if we could look inside too, our inside bits and pieces gracefully age too. As that happens, GFR falls … maybe at about 1ml/minute on the average each year – or 10 ml/min each decade. It’s kind of meant to! This decline begins somewhere in the 30-40 year age bracket (on an average) … so by the 70’s and 80’s, many are approaching an eGFR which is certainly ‘Stage 2’ and even ‘Stage 3’ … but without other signs/features of kidney disease evident … c’est la vie. It is unlikely to matter (unless you name is Methuselah!).

Early Stage 3, for the elderly, isn’t usually wrist-slitting territory!

Now, I am assuming your relative is younger. That has different connotations – but this depends on the underlying cause of her renal disease. This is best discussed with her doctor – and if this is not yet a nephrologist, it would be wise to consult one. He/she will be able to ‘context’ the eGFR and its meaning within the total picture.

Importantly, is she a diabetic? Many diabetics with early diabetic nephropathy will have a declining eGFR (usually slowly) and have a condition common especially to diabetes called hyporeninaemic hypoaldosteronism … to pronounce that, try it slowly - hypo…renin…aemic hypo…aldo…steron…ism


This is a fancy name for a common condition in diabetics (and also to a lesser extent in other – often older – people) where low (not high) renin production leads to a low adrenal gland production of a hormone called aldosterone. As aldosterone promotes potassium loss from the kidneys, a low aldosterone level tends to cause the kidneys to hang onto potassium … and the blood potassium rises. This is usually a well tolerated condition and most nephrologists are quite happy to allow the potassium to rise to the high 5s … often with an ACE or ARB … though care needs to used at the lower ranges of eGFR and/or with intercurrent illnesses – especially if these illnesses deplete the blood volume (dehydrate) … like the nausea with vomiting … or the trots!

Back to the potassium level … and at 5.3? … well, I don’t want to sound blasé, but at that minimally elevated potassium level, especially as this is already on an ACE inhibitor (and, by the way, lisinopril is not a potassium-sparing ACE … they don’t exist … as all ACE agents (and ARBs) will tend to elevate the potassium) … I’d not be at all anxious nor worried … nor even getting too carried away (with an eGFR of 50) in advising any special potassium management.

Maybe we Australians are more ‘relaxed’ about potassium, but 5.3 doesn’t, to me, sound any special alarm bells at all.

OK … I would agree, don’t flood with high potassium foods, maybe … but I wouldn’t be counting the potassium intake … I wouldn’t be trying to sweat potassium (a pointless exercise anyway) … I wouldn’t be using a potassium-wasting diuretic (unless her BP, volume status, certain other medications which I do not know about or other clinical data of which I am unaware dictated otherwise) … indeed, I’d be a bit relaxed about it all (especially at an eGFR of 50 and a potassium of 5.3). I’d be telling her to go off and be normal!

OK … don’t have a banana split followed by a star-fruit salad and chased down with chocolate truffles laced with orange and lemon rind and a thirst-quenching citrus smoothie.

In other words … be sensible, not paranoid. In short, she ain’t likely at risk!

Now … all that is said without knowing the individual patient. However, I cannot conceive of a significant situation in a stable, otherwise well, young(ish) woman on an ACE with an eGFR of 50 (presumed stable) where I’d be getting at all toey about a potassium of 5.3 … or even 5.5!

I start to ‘note’ in the upper half of the 5’s … and advise sensible measures … but am prepared to accept, in some patients, a potassium to 6 before I’d be backing back off the ACE or thinking resin therapy to bind the potassium or going ‘bananas’ (pun intended) over strict and stringent diet.

Certainly in the high half of the 5’s, intercurrent illness can be the destabilising factor … but in a stable, well patient, I am happy to stand by what I have said.

As for an ACE (here, lisinopril) to ‘protect’ her kidneys … absolutely!

ACE … drugs that end in ‘pril’ … and ARB … drugs that end in ‘sartan’ … do help protect the kidneys … well, almost all of the time, and in almost all patients. This last statement shows that the clinical situation is important to know, as there are times where the rule doesn’t hold true … but, gee, these aren’t common!

These drugs reduce the internal ‘pressure’ inside the little filters (called glomeruli) of which there is anywhere between 300,000 and 1,500,000 per kidney.

It is the ever-rising internal ‘glomerular’ pressure that parallels the slow progression of CKD that, ultimately, contributes to or even is the major cause of progressive, irreversible glomerular damage.

Lowering the internal pressure in the glomerulus (ACE and ARB are usually spectacularly good at doing this) helps to lessen the damage that rising pressure does … and thus they slow the progression of kidney disease.

But … these drugs, by lowering the internal pressure, lower the ‘squirt factor’ too. The ‘squirt factor”? … well, the filter filters best under pressure. Think of a soak-it hose in the garden … turn the pressure down? … less squirt!

But … that’s another talk and answer altogether!

For now, ACE and ARB (‘prils’ and ‘sartans’) lower the pressure, protect the filter from pressure-caused damage and help to preserve the kidneys longer term.

But, by lowering the pressure, the ‘squirt factor’ is lessened too … and this may knock a few ‘points’ off the eGFR!

GFR depends on the degree of ‘squirt’ across the filter membrane … lower the pressure, lessen the squirt, drop the eGFR.

Normally this is NOT an issue. An eGFR of a few less ml/minute isn’t a problem. It’s like having friends to stay and your hot water service is limited! Turn the pressure down a bit on the tap, and the water will last for everyone. Run it full bore (your 17 yr old son!) and there will be none left for the guests! Yet, turning down the tap a notch or two doesn’t really cause a great deal of trouble … everyone will still get an adequate shower!

So it is with the kidneys … turn down ‘the squirt’ a little … makes very little meaningful difference but it DOES lessen the pressure … so the glomeruli (and the kidneys) last longer … usually much longer!

There … that’s exhausted me!

I hope that explains stuff.

Reassure your relative. All’s not lost!

Be sensible, but not paranoid.

Be normal, not diseased.

Live fully, not cocooned.

But … talk it all over with a nephrologist. A 2 month review (not knowing the cause or clinical details) seems OK to me.

Hope that helps …

Thank you, Dr. Agar, for “breaking the rule” and answering this post. I didn’t know where else to put this. My relative had turned to me for some advice, knowing that my father has CKD and is nearing the point of having dialysis. So, I guess she figured I’m knowledgeable in this area & she doesn’t want to get to that dialysis stage. But, I’m not a doctor, so I didn’t want to give her wrong info. I do appreciate your answer, which I will definitely relay to her. This should calm her fears.

Just for your info, she is in her early 50’s, but looks younger. She walks about a mile daily and eats pretty healthy. Maybe that’s why her potassium is little high – she does eat a lot of those high potassium foods. Her doctor told her to watch her potassium intake & gave her a list of low potassium foods, which she found very restrictive, so I guess that disturbed her. BTW, her doctor is a nephrologist, but she won’t visit with him again until 2 months later, so that’s why she was asking these questions now.

You explained things in a very understandable manner. Maybe others that read this post will be helped as well, so again, I thank you for your response.