Managing feline kidney disease: The 2026 Consensus Guidelines

In the September open access episode of Chattering With iCatCare, sponsored by Elanco, Yaiza Gómez-Mejías is joined by feline specialists Natalie Finch and Sam Taylor to introduce the new consensus guidelines on feline chronic kidney disease. Reflecting on a decade of progress, the conversation explores how our approach to diagnosis, risk factors, and long-term care has evolved.

They discuss why standard SDMA cutoffs can be misleading in older patients, the crucial distinction between two commonly confused renal stone conditions, and how certain renal diets might unexpectedly trigger hypercalcaemia. Natalie and Sam also highlight novel therapeutic options for CKD anaemia, explore the gut microbiome's role in uraemic toxin buildup, and share why moving from reactive care to proactive screening transforms patient outcomes.

For further reading material please visit:

2026 iCatCare consensus guidelines on the diagnosis and management of chronic kidney disease in cats

MyElanco - Elanco Resources for Veterinary Professionals

IRIS Kidney Disease Guidelines & Staging System

Host:

Yaiza Gómez-Mejías, LdaVet MANZCVS (Medicine of Cats), RCVS CertAP (Feline Medicine), iCatCare Veterinary Community Co-ordinator

Speakers:
Natalie Finch, BVSc, PhD, DipECVIM-CA, FRCVS, European Veterinary Specialist in Small Animal Internal Medicine, RCVS Specialist in Feline Medicine

Samantha Taylor, BVetMed(Hons), CertSAM, DipECVIM-CA, FRCVS, Veterinary Specialist Consultant and Veterinary Specialist Lead at iCatCare

Creators and Guests

Host

Yaiza Gomez-Mejias

Veterinary Community Co-ordinator @ International Cat Care

What is Chattering with iCatCare?

Welcome to Chattering With iCatCare, the official monthly podcast of International Cat Care, hosted by Yaiza Gomez-Mejias (Veterinary Community Co-ordinator). Each month, we chatter about cats and cat-friendly practices with industry experts and contributors to The Journal of Feline Medicine and Surgery. If you would like access to our members episodes become an iCatCare Veterinary Society Member and get in touch.

Yaiza Gomez Mejias: This episode is brought to you by ELANCO. Welcome back to Chattering With iCatCare. I'm Yaiza Gomez, iCatCare Veterinary Community Coordinator, and today I have the privilege to interview Sam Taylor and Natalie Finch about the new guidelines on feline chronic kidney disease. The aim today is not reviewing all the content, but simply introduce the guidelines so you can then read them if you feel interested. So thank you very much Natalie and Sam for joining us today, and it has been 10 years since the last consensus. In general terms, how has the clinical approach to feline chronic kidney disease changed between then and now?

Natalie Finch: Thank you for doing this interview with me. I'm absolutely delighted to be here and to be here with Sam. So to answer your question, I'm gonna talk about the most recent things in diagnosis and etiologies and risk factors, and then also management.

So in terms of diagnosis then, I think what hasn't changed is our use of creatinine. So it is our most widely used and established surrogate marker of GFR. We know lots about how to use it, we've got lots of information on it. But what has evolved perhaps is our understanding of the benefits of the repeated measurements of creatinine. So using a cat where it serves as its own baseline to look for progressive increase in creatinine concentration that might alert us to the possibility of either progressive disease or the development of azotemic chronic kidney disease.

10 years ago we did have SDMA available and at that time, the initial studies were suggesting that SDMA had a greater detection for decreased renal function than creatinine, but we've had lots more studies since that time, and so now we know that actually the correlations between SDMA and GFR and creatinine and GFR are probably similar.

SDMA is less affected by muscle mass than creatinine and so it can be beneficial when we're using it in those cats with chronic kidney disease that may have lost muscle mass, those underweight cats. So perhaps we want to consider SDMA in our interpretation of our renal profile more in those cats, but we do also know now is that it is affected by other non-renal factors. And most importantly for our older cat population and that's gonna be hyperthyroidism. So we need to interpret it with proportion in a cat where we may think that there's underlying hypothyroidism. And now we've also got increasing evidence that perhaps the standard commercial assay cutoff, the 14 micrograms per deciliter, may not be appropriate for the older cat population either and perhaps we should be using a higher diagnostic cutoff of 18 micrograms per deciliter in our older cats.

But in terms of etiologies and risk factors for chronic kidney disease in cats then, we've got increasing evidence, both in humans and wild and domestic cats, because we know that wild cats too also get a lot of tubular interstitial nephritis and chronic kidney disease.

We've got increasing evidence that dietary phosphate is playing a role in the development and progression of chronic kidney disease, and that's because the high dietary phosphate which we might see in some diets will mean that there's more phosphate within the renal tubules and that phosphate in the renal tubules is causing cellular stress and nephron death and the interstitial fibrosis and inflammation.
We now have a better understanding of nephrolithiasis in feline chronic kidney disease. So we can see incidental nephroliths in lots of cats with chronic kidney disease, and that doesn't seem to be associated with progression of chronic kidney disease, where the problem is if they move to cause a urethral obstruction and that urethral obstruction can cause renal injury.

So where we've got a  nephrolith, so a lith, a stone within the kidneys, within the renal pelvis, that if we see that incidentally, that's probably not an issue for a cat with chronic kidney disease. It's if it moves and blocks in the ureter that we're going to see renal injury. And I think at this point also, I just want to discuss the difference between nephrolithiasis and  nephrocalcinosis because these terms are becoming increasingly common.

So nephrolithiasis is the, is a stone, a lith that we're seeing within the kidney, whereas  nephrocalcinosis, that's the deposition of calcium within the renal parenchyma. And we know that hypercalcemic cats are much more likely to develop  nephrocalcinosis, and that may be a risk factor for progression in cats with chronic kidney disease as well.

And then finally, there's a few really important management changes or things that we recognise now that is really important for management of cats with chronic kidney disease. So chronic kidney disease, mineral bone disorder. This is the biochemical changes, the soft tissue changes, the bone changes that we see in patients with chronic kidney disease.

We see it in all species with chronic kidney disease and the pathophysiology is quite complex, but it's been really well described in the guidelines. So if that is something that you are interested in, we've got lots of detail and also some really great visual diagrams to help with understanding of that.

And the reason it's important to recognise in our clinical patients is because we know it contributes to progression of chronic kidney disease, and if we recognise it then the primary management is going to be around phosphate restriction and trying to achieve the phosphate concentrations for the iris target for that stage.

We will also have FGF23, which is available now as a commercially available marker, and that's helpful in determining whether or not that phosphate restriction is required for cats that may be an early stage disease and where they don't have phosphate above the iris target, we need to know is phosphate restriction going to be beneficial?

And so iris have made some recommendations for cutoff, which we've described in the guidelines for when actually measuring FGF23 to guide us about whether or not we need further phosphate restriction, whether that's going to be helpful. Another thing in the management of chronic kidney disease that's becoming a really hot topic is the diet induced hypercalcemia.

So this is different from cats that are hypercalcemic at diagnosis. These are cats that we recognise when we feed them a standard renal diet that they will develop hypercalcemia, and we think this is related to the calcium phosphate ratio of the diet. The standard renal diets will have a higher calcium phosphate ratio because they're more restricted in phosphate.

And so that higher calcium phosphate ratio, we think, is leading to more increased absorption of calcium through the gastrointestinal tract, and that's contributing to the development of hypercalcemia. And so actually, if we can feed them a diet that has a lower calcium phosphate ratio, they're going to absorb less calcium and then they will hopefully resolve that hypercalcemia.

And indeed, actually in the studies where they've looked at feeding, transitioning from what we would call a standard renal diet to then an early renal diet, those cats that have developed hypercalcemia, that hypercalcemia will resolve when they're fed an early renal diet with a lower calcium phosphate ratio.
I think anaemia is becoming increasingly important. We know that anaemic cats with A PCV less than 27% will have a reduced quality of life, and previously we've only really had access to things like darbepoetin and recombinant human erythropoietin. Which we know have been really significantly associated with the production of anti erythropoietin antibodies, particularly for recombinant human erythropoietin.
But now we've got the HIF inhibitors and these HIF inhibitors work by essentially mimicking hypoxia in the body so that there is stimulation of erythropoietin production. And we've now got several studies where our cats with chronic kidney disease have been given molidustat and they've demonstrated a significant increase in their PCV.

And we've included protocols in the guidelines about dosages, how to monitor the cats when you're giving this medication. And then the final thing I wanted to talk about is the gut microbiome. I think that's really important for so many diseases in cats and we know that cats with chronic kidney disease will have faecal dysbiosis, and that's probably a contributing factor to uremic toxin accumulation.

Things like in indoxyl sulphate and peak crest or sulphate. And the uremic toxin buildup is important because it's associated with progressive chronic kidney disease, and we want to doing everything that we can to preserve renal function and stop progressive chronic kidney disease in our cat. So by maintaining a healthy gut microbiome, by potentially giving probiotics and prebiotics, hopefully we can reduce that.
And another consideration in that is monitoring defecation in cats. So cats with chronic kidney disease may be more prone to becoming constipated and so that can exacerbate this buildup of uremic toxins because we've got faeces sitting within the colon for longer. So monitoring hydration status, defecation in the cats, giving laxatives and making sure they're staying well hydrated if we're concerned about constipation.

Yaiza Gomez Mejias: Wow. Thank you so much. I think it's brilliant. Would you like to add something, Sam?

Samantha Taylor: Natalie's been very comprehensive there and I think it's funny. It is an area of feline medicine that thankfully has had lots and lots of research. Partly thanks to Natalie and the groups at the Royal Vet College. When I do some guidelines, we don't have as much to go on, whereas this one, I think I have beaten my record for number of references in a guideline.

So that shows you how much research there has been. And often, as we know, cats are behind dogs in research. But I think this might be one, I dunno if you agree Nats, that there might be a bit more research in cats than there is in dogs. So for once we're probably ahead of the game. So yeah, I think it was well due an update for all of those reasons that have been mentioned, but also just being more proactive and the things we've learned about simple things like constipation, things that really affect cat's quality of life, I think we've just got a lot better at, and hopefully these new guidelines will refresh everybody's interest in this topic.

Yaiza Gomez Mejias: And getting back to what Sam said, why is it important to move from a reactive to a proactive approach where instead of waiting for the azotemia to appear, we screen more often.

Natalie Finch: So lot of the signs in chronic kidney disease are perhaps not very obvious to owners, things like polyuria, polydipsia, inappetence, those signs may be quite subtle and insidious, also quite non-specific. We know actually that many cats with chronic kidney disease will have weight loss that's gone unnoticed for a large period of time before the diagnosis.

One study showed that weight loss for about 9% in the 12 months prior to the lead up to diagnosis. So then if actually we screen those cats where the owners have noticed no signs at all, cats that are considered to be apparently healthy, then quite a significant proportion will have evidence of azotemic chronic kidney disease, and then many more, if you were to follow those cats over a one to two year period will develop azotemic chronic kidney disease. By having a more proactive approach, we can hopefully detect the disease earlier. We can monitor the cats to look for signs of progression that might alert to progressive changes in the  creatinine that might alert us to the development of azotemic chronic kidney disease.
But I do just want to highlight at the moment that if we have early detection, maybe we can implement some management strategies, but we have quite limited evidence at the moment for early intervention in early stage chronic kidney disease. So we've actually only got one very recent 2026 retrospective study looking at a really large number of cats to see whether or not early intervention with a renal therapeutic diet is beneficial.

And that study was able to show that the cats in stage one and early stage two chronic kidney disease that were fed that renal therapeutic diet did have slower progression and increased survival compared to the cats that were not fed the renal diet. We need a lot more research in that area, but where it will be important that if we have recognised that a cat has early chronic kidney disease, then we can start to consider that in the home environment and the hospital environment.

We can start to consider it and if we're prescribing any medications for cats, if we're thinking about the cat needing any procedures, requiring a sedation or a general anaesthetic, thinking about anything that might have an insult, an injury, whether that's ischemic or something else to the kidney that's going to worsen that kidney disease.

So, thinking about making sure cats stay nice and hydrated, particularly in hot weather like this, making sure there's lots of sources of fluids within the home environment. Maybe early intervention in a cat that's developing vomiting and diarrhoea or inappetence to make sure that they're maintaining that renal perfusion when they do have early chronic kidney disease that might contribute to progressive chronic kidney disease if we don't address it early on.

Yaiza Gomez Mejias: Would you like to add something, Sam?

Samantha Taylor: Yeah, I think it probably also comes back to early detection of chronic kidney disease is of course important, but we also might detect other diseases as well. So I suppose I would just broaden it also to getting cats into the clinic and getting senior cats into the clinic.

So even if, I think it's right what Natalie says, that it might not mean that we do an enormous intervention and can cure the problem, but it's starting to notice those cats, it's getting them in. It's looking at their body weight, their body condition, detecting if they have dental disease, as Natalie said, does that need management?

Let's do that now rather than leave that. So I think it's part of a whole sort of attitude really, I suppose, to getting these cats into the clinic and of course being more cat friendly, as we know, will help us to do that. So I think, of course we're talking about chronic kidney disease, but to me, I would broaden it to just knowing our senior cats a bit more that are on our books.

We often lose them a little bit, don't we? We might see them as young cats for vaccination and the healthy adults. And then you start to get in this period where, and so they're a bit older now, I don't wanna take them into the clinic and stress them out, or they look fine or they're just getting old, you know, that classic sort of attitude.

Whereas actually we can do a bit better, we can identify illness and I'm still constantly amazed how much difference you can make by doing that. For example, doing dental treatment in a cat with early chronic kidney disease, it can, that can improve their appetite, it can just improve their demeanour and then they drink a bit more. They eat a bit more. I feel like it would make a big impact on potentially even progression, as we said, by encouraging them to just improving their general health at that point that you've diagnosed it to me is a positive thing.

Yaiza Gomez Mejias: Thank you both, Sam and Nat, for joining us today and to the audience this is just the first step in our series. Those who are members of the iCatCare Veterinary Society will be able to listen to more podcasts on renal disease in cats around monitoring CKD, urinary tract infections and nutrition. So keep an eye on future episodes and thank you for listening. Please leave your feedback on social media and see you next month. We want to thank ELANCO for the support