Good evening everyone and welcome to tonight's Platinum members webinar. Feline CKD what's new in diagnosis and treatment. I'm sure many of you have been on webinars with us before, but I'll just do a quick bit of housekeeping with you if that's OK.

So if you do have any technical issues at all, it does sometimes happen. If you leave a message in the chat function or the chat box that should be, popping up on your screen if you hover your mouse over the screen, myself or my colleague Dawn will be on hand to try and help out. If you have any questions, for Sarah during the talk, please do feel free to submit the questions into the Q&A box.

We'll get through as many as we can towards the end of the presentation. So on to tonight's webinar, we're delighted to have a fantastic Sarah Kaney with us. Sarah's an RCVS specialist in feline medicine and enjoys seeing referral and first opinion patients.

She's written a number of books including Caring for a Cat with Chronic Kidney Disease, published by her company Vet Professionals. Sarah does a lot of owner orientated research through her website and has a particular interest in geriatric feline medicine. So without further ado, I shall hand over to Sarah.

Thank you very much and thank you for choosing to listen to this webinar. I do hope that you find it a useful way to spend your evening or daytime if you're listening to this after the event. CKD is definitely a topic that's very dear to my heart.

It it represents an area of feline medicine that's constantly advancing and constantly helping us to do a better job of both diagnosing and managing. This ultimately progressive condition, so it's, it's not a, a good condition to be diagnosed with, but thanks to all these advances, I think we are able to do a really much, much better job than was the case certainly 5 or 10 years ago. I put my email address on this slide, and I think it's on the final slide as well.

But if there are questions which you don't feel are adequately covered in the Q&A at the end, you're welcome to email me on this address. And also, if you would like a PDF of the slides that I've used for today's presentation. Then please also do feel free to email me and request them.

If you could, if, if asking for the, the PDF of the slides, if you could actually put the title of the webinar and say it was through the webinar that, that would be great because then I'll know exactly which presentation you're after. So you had a little bit about me in the introduction, from Paul, and this is just a summary again, with some pictures of book covers. So you can see, the kidney book is the, the purple cover in the top right hand side of the slide.

But there are a number of other books that I publish, many of which I've written or co-written, and, are available in electronic and print form. And also, as was already mentioned, I really enjoy doing online owner surveys, and we always have Number of these open. We do some in collaboration with students at universities around the world.

If you have an idea for a survey, something you'd like to study, then please get in touch. But also have a look at the website, vetprofessionals.com.

You can actually look at the survey page to see what's going on and also how you can support our surveys through your vet clinics and other ways as well. I'll also refer during my presentation to some resources that are on my website, and there is a menu item called Helpful info at the top of the vet professionals website. If you scroll down, you'll see one of the options is free downloads, which is a whole range of technical documents.

That are aimed to support both owners and veterinary professionals, so vets and nurses are on a range of topics, and there are some relevant to CKD, for example, how to collect urine sample by cystocentesis, how to measure blood pressure and interpret blood pressure in cats, also how to look for ocular manifestations of High blood pressure. So, all these sorts of things, and as you can see from the name Free to download. So, please feel free to access that.

You do need to register to, to be able to access them. But you, you can completely opt out of any further communication from, from us. So you don't, you're not signing away your life.

It's just, there is a, a slight hurdle to getting through to that page. So, before I go any further, actually, I just wanted to ask for the people who are listening to this event live, are you a vet, a vet nurse, a student vet or a student vet nurse or, or something else? If you could, let me know, that would be useful just in terms of, the remainder of the presentation and how I orientate it.

Thank you. So we just let that run for another 30 seconds or so, we've got 2/3 of people who have voted, so far 100% vet. OK, voting seems to have come to a stop now.

So yes, 100% of people online are vets tonight. And that was a nice easy question to be asked, wasn't it? Who are you?

Thank you very much for. So great. And, and obviously this, this presentation primarily always has been orientated towards vets, but I would really encourage you to involve your vet nurses in the diagnosis and management of CKD cats as well.

I think nurses can play a really important Role in helping to pick up these cases at an earlier stage, and also in the long term management are often very good at, for example, communicating to clients about the importance of dietary management and explaining how to transition to new diets, etc. So, I really, I, I encourage you to use your nurses to to their full potential. So of course the title was What's new, and so really I want to focus on two aspects.

One is, the diagnosis and in particular making an earlier diagnosis because there have been some advances in this area in recent years. And then secondly, from a management perspective, what do we know that's sort of adding to our ability to, to manage this condition? What can I tell you that's new on that score?

And something that is relatively new, just a couple of years old now, are these guidelines which were written and published by ISFM, the International Society for Feline Medicine, and published as a free to access for all people, journal article in the Journal of Feline Medicine and Surgery. And these guidelines, are one of a number of guidelines actually that ISFM have produced. For example, there are guidelines also on managing hyperthyroidism, diabetes mellitus, and other topics as well.

As you can see from the partly included author list on the right hand side, I was one of the authors involved in this, but it was an international panel that got together and devised these guidelines that the aim of which really was to be able to say for those people at the, the coalface of the, of the feline medicine, which is you guys in your clinic seeing these cases in a first opinion setting, what is a sensible way to diagnose and manage this condition. And I will extract some of the nuggets from this, these guidelines through this presentation. But if you do have an interest in CKD, I'd really encourage you to download these guidelines, and, have them available to use for your next case that you see.

So let's talk first about diagnosis of CKD and how this has changed a little bit in recent years. Certainly for the most part, traditionally, and still, I think often nowadays as well, the main route through which we're making a diagnosis of CKD in an individual patient is because they are presented to us with some concerns. So there is some sort of clinical suspicion that might fit with CKD.

Perhaps this is a cat that the owner is worried is either lost. Weight, drinking more, has been vomiting. Or there are some suspicions that come through, perhaps on a booster vaccination check, that perhaps alert us as clinicians.

Well, yes, this cat actually is a, you know, has lost half a kg since last year. And that leads us to consider CKD as a possibility, do the appropriate laboratory tests and confirm that diagnosis. So this obviously is still the the most common pathway to make the diagnosis of CKD.

But there has been, certainly in the last 5 to 10 years, more and more emphasis on what we can do in terms of health screening and the potential value with diseases like CKD by screening apparently healthy animals. So these are animals where the owner has no clinical concern of any illness whatsoever. But we are choosing to look at them a little bit more closely with the hope of identifying common diseases, in particular in the older cats, where the the population we tend to focus on.

And that now is becoming increasingly commonly, a, a route for diagnosis of CKD. There are a number of things that we can look for in terms of our signalments and in terms of our history and our clinical examination that will raise our suspicion of CKD. And of course, none of these in isolation is diagnostic for CKD.

We always need to do more to confirm that diagnosis, but As you'll all know, it does tend to be most common in older cats. Conservatively estimated that at least 3 of cats over the age of 10 have some renal impairment, probably more than half of cats over the age of 15 having some evidence of CKD. So it is incredibly common, particularly in that older cat.

And common clinical signs, which an owner might notice would include increased thirst, increased volume of urine produced polydipsia, polyuria, and weight loss as listed on this slide. And the percentage figures in brackets actually come from an owner survey that I did through the vet professionals website a few years ago, and that also was published in the Journal of Feline Medicine and Surgery a couple of years ago. And as you can see, whilst, you know, polydipsy, polyuria, weight loss are at the top of the list of of common clinical signs, it's still only really up to half of the cats showing those signs, which means that half of the cats with CKD did not show obvious polydipsia or weight loss, for example.

So whilst these are useful indicators, we do need to remember that many cats with CKD may be free of clinical signs or or have perhaps only very subtle clinical signs. Physical examination, there there are some clues that can sometimes be helpful. Certainly if we have abnormal feeling kidneys, very large or very small or asymmetrical, that raises the suspicion of CKD.

But again, quite a large number of cats with CKD have normal symmetrical shaped kidneys. So that's not certainly not something that we should use to rule out CKD. And similarly, presence of dehydration, evidence of anaemia, evidence of high blood pressure again, CKD will be an important differential, but there are other differentials for these things as well.

So we need to keep our eyes and ears open looking for these sorts of changes, and coming back to the routine health screening, I'm a very passionate advocate for more proactive healthcare, particularly of those older cats that are at risk, and for many years have been following guidelines. That were devised by International Cat Care. And they have recently, 2018 updated their guidelines and now rebranded them.

They're called the Cat Care for Life, and you can see the website bottom left there, catcare number 4life.org. And what IA care recommend through these new guidelines is that firstly in your young to middle aged cats, an annual health check, including a full history, physical examination and weight check, as we would all currently recommend is adequate, but that once the cat Reaches the age of 7, we start to be more proactive and a bit more detailed in our assessment.

So ideally, where it all possible, including our annual health check for the mature aged cats, the 7 to 10 year olds, a blood pressure check, a urinalysis, and a blood profile. And I'll talk more about the urine and blood, what we're looking for in in just a moment, but, from a urine perspective, that can be a free catch sample or a cystocentesis sample, whatever is easiest for you, the cat, and the owner to get. And then for our senior cats, the 11 to 14 year olds, now we consider seeing the cat more frequently.

So we consider, if possible, seeing the cat twice a year rather than once a year, and also consider adding a T4 to our blood profile. And lastly, for our now called super senior, what we used to call the geriatric cats, cats aged 15 years and over, recommendations from IA care actually similar to the seniors. I would encourage you actually to try and get those cats in for a health check, by which I mean, a physical examination, a history, a body weight assessment every 3 months if you can, because, for some elderly cats, 6 months, you know, can be quite a lot of weight loss if they, if they do have any sort of clinical problem.

And if you visit the Cat Care For Life website, you'll see they have all sorts of resources available to support you in introducing this into your clinic. Blood pressure measurement, definitely a vital component of your senior cat checkup. And I have a lot of resources on the free the free download section of my website, vetprofessionals.com.

I mentioned at the start. So just a reminder of that, that you can access guidelines on how to look at the eyes, what pathology to look in at in the eyes, how to interpret blood pressure, etc. Via my website.

Something that's very simple, is to weigh cats, and actually it's really helpful to understand how significant weight changes, can be in cats. And one of the ways we can look at significance of weight changes in cats is actually to do a very quick percentage weight change calculation using the equation that I've shown at the top of this slide. So if you haven't seen this cat for 6 months or 12 months.

You're following your ICA care, preventative healthcare checks. And the cat has lost some weight. Calculating percentage weight change will allow you a way of determining, well, is this actually a significant amount of weight?

And I typically will put a 5% cut off on significance, when doing this, calculation. If the patient's lost less than 5% of their body weight, then as long as everything else is OK, I'm, I probably am going to give them the benefit of the doubt. I'm not gonna immediately, recommend investigations, although I might want to recheck the cat's weight perhaps in a month's time.

But If the cat's lost 5% or more of their body weight, even though in absolute terms, that's typically only a small amount of of grammes or, you know, fractions of a kilo. So for a 4 kg cat, 5% weight loss is 200 grammes, doesn't sound very exciting. But actually, like ourselves, our cat's weights does not fluctuate much day to day in percentage terms.

So if we scale that up to a person weighing about 65 kg, which is roughly 10 stone, 5% weight change would be 0.5 a stone, more than. 3 kg and our weight does not fluctuate that much day to day, and neither does the cat.

So looking at percentage weight changes, I think can be helpful. Also really important to assess body condition score and of course muscle condition on every visit that the cat comes into the clinic. This paper was published a couple of years ago and actually showed quite nicely the value of looking at body weight in a population of cats, cats, and this study, which involved a large number of cats, a total of 569 cats.

These were cats where a diagnosis of CKD had been made, but they also had. Weight readings from these cats going back for several years. And what they found was that actually the cats had lost a median of nearly 10% of their body weight in the 12 months before diagnosis.

So actually quite a large amount of weight, the equivalent of almost that 10 stone person almost losing a stone in body weight over that 12 months prior. Prior to diagnosis, but they also could see that that weight loss actually was already present several years earlier. So if you have practise software that allows you to plot a chart or a graph of any description and you can see the weight is just drifting down, even if it doesn't look very dramatic, even if perhaps that cat was overweight in the past.

The fact that it is drifting in a downward direction should be taken as significant and and would be one justification for doing further investigations. And one of the easiest initial investigations to do is actually a urinalysis, and this is obviously part of the IA care and preventive medicine checkups as well, in that they recommend an annual urinalysis from the age of 7, with it being 6 monthly in cats aged 11 years and over. And the key thing really that we're Most interested in here is the urine specific gravity that should be measured using a refractometer.

So don't ever use the USG dipsticks. But that urine specific gravity, you're using a refractometer is a really helpful indication of whether the cat is able to concentrate its urine. And the advantage also of that urinalysis is that firstly, it's very quick to perform.

You can even do it without the cat. So if you have a client who walks in or phones up to say they're a bit worried, the cats may be drinking a bit more than it used to, getting them to drop off a urine sample, is gonna help you in your investigations and, and even in that initial point, you don't need to, to take the cat in. Of course, we're always gonna want to see the cat at some point.

And typically, you're in specific gravity will be one of the first things that starts to to be affected by CKD, so a fall in SG before the cat becomes azotemic. And the cutoff that we use in cats, different to dogs, is 1035. So if the cat has urine with a specific gravity of less than 1035, that is generally considered to be abnormal unless there is a physiological or iatrogenic reason for that, for example, this cat's on diuretics or it's always been fed a liquid diet and it loves cat milk and has a food that resembles soup.

If anything like that exists, of course, we need to consider those as reasons for the reduction in USG. But for 99.9% of cats, a USG less than 1035 is abnormal because of of pathology.

And the main differentials would be kidney disease, hyperthyroidism, and diabetes mellitus. So of course, we can follow up with the dipstick thinking of diabetes. Dipsticks are not that reliable for many parameters, but they are, they are good for glucose.

So we can use that as a, a helpful test from that perspective. And In a confirmed CKDA, of course, we often want to do further investigations to look for, for example, proteinuria, urinary tract infections. So the urine sample is really key to our assessment of the cats, and even just that specific gravity is part of the health check, incredibly helpful.

Thinking again of those preventative healthcare checks, so those IA care recommendations, you'll remember that blood tests were recommended if possible from the age of 7 years upward, but I would certainly prioritise for the cats aged 11 years and upwards. And in a perfect world, the ideal scenario is to do as detailed a profile as you as you can afford. So a haematology, a serum biochemistry, and if possible, a total T4.

And if you are using IDEX facilities and can include an IDEX SDMA in your biochemistry profile, so much the better. We'll talk more about SDMA in just a moment. If doing that complete panel just is too cost prohibitive for either your clinic or your client, then what most clinics would typically offer as a pre-anesthetic screen is going to be very worthwhile still.

So that might just be a PCV from a haematology perspective. Urea, creatinine, proteins and liver enzymes from a biochemistry perspective. But of course, if you do find evidence of renal disease, following up with more detailed biochemistry, looking at electrolytes and phosphate, for example, is very much an advantage if at all possible.

So the checklist for initial assessment, having diagnosed CKD is actually quite long. We'll talk more about how exactly we confirm the diagnosis in just a second. But, by now, hopefully, with our older cat, we'll have done obviously a detailed history and physical examination and our blood pressure.

But having received a diagnosis of CKD, we will want to do more detailed urinalysis. We'll want our blood profiles. And if you do have imaging facilities and can do.

Ultrasound of the kidneys, that also is helpful. The aim of which all these procedures really is to try and understand as much as we can about the CKD, see if there is ongoing active disease that needs management, see if there are complications that would benefit either symptomatically or in other ways from management. Also, don't forget that because this is an older cat, having concurrent disease is very common.

So we want to make sure we we have as complete a picture as possible to provide the best for our cat. So how do we assess renal function and actually confirm that diagnosis of CKD? Well, in a perfect world, we would measure glomerular filtration rate, GFR.

That is thought to be the best measure of functional renal mass, and it is actually possible to do this, even from a, a, a, a clinic, you don't have to be in a research institution anymore to, to do this, but it is expensive, and it's not necessary in every case to actually make a diagnosis. So typically what we will do this sort of a well trodden route to diagnosing CKD will include measuring creatinine levels in the blood and seeing whether there is azotemia, increased creatinine levels, and the the 140 figure on this slide is the iris cut off for AZT. That I've included there.

We also want evidence of poor ability to concentrate urine, so a reduction in urine specific gravity, 10:35 or less as as discussed. Evidence of criicity that these changes have been present for some time and also compatible history. So that all fits together.

And then more recently, SDMA has also added to the list. So an STDMA greater than 14 would also be potential evidence of CKD as I'll, I'll talk about in more detail in just a moment. It's worth remembering that urea and creatinine are not perfect, and whilst we're very familiar with looking at these on our profiles, just to remind you that in particular, urea is, is often problematic because it's excreted at a variable rate and it can be reabsorbed once it's been filtered at the glomerulus.

And this is of particular relevance if you have a patient, canine or feline, that's dehydrated. If you're dehydrated, then the the flow of the glomerula filtrate is slowed down as part of the body's ability or response to try and conserve fluid, allow more fluid reabsorption from those nephrons, that also allows ear to diffuse back into the circulation. And this is why dehydrated cats and dogs have disproportionately higher levels of urea compared to creatinine.

So creatinine is the main one to look at, but it too is not perfect. And whilst levels are inversely proportional to GFR, so the higher the creatinine, the worse the GFR, it's not a straight line. We can't extrapolate what GFR is just from a creatinine reading.

And both your ear and creatinine are affected by things outside the kidneys. And really the key thing in terms of creatinine is how much muscle mass the cat has. Creatinine comes from muscle turnover, so if you're very well muscled, an entire male cat, for example, you will be generating a lot of creatinine.

And even if your kidney function is very good, if you are a very well muscled cat, your blood creatinine levels actually may be slightly higher than a standard typical laboratory reference range. But we have the opposite problem in our target patients, the ones we're most worried about CKD in that these are typically the elderly, thin, poorly muscled cats. So they are at the bottom of this table here, where you can see that if you have a little muscle mass, you're not going to generate much.

Creatinine, which means that even if your kidney function is poor, levels of creatinine may not accumulate to the same extent. In other words, we may be misled by that low or only slightly elevated creatinine in thinking that the cat's kidney function is better than it is. So this is the main thing we need to be aware of when doing our, our lab profiles and looking at our patients.

We can stage the severity of our renal disease according to creatinine levels, and this summarises the Iris International Renal Interest Society staging system, which, as you can see, for cats with kidney disease, goes from 1 to 4, stage 0 is just cats at risk of. Cats that are non aotemic with kidney disease are those that are known to have kidney disease because of of other abnormalities. So that could be Cat that has enlarged polycystic kidneys or renal lymphoma, for example, where you know via ultrasound and or biopsy that there is pathology in the kidney.

But at the moment, the cat's excretary function is adequate, hence them being non aotemic. But as you can see right through to stage 4, severe renal aotemia creatinine, in the UK units greater than 440 micromoles per litre. More recently, we have now a newer measure of renal function that is available through IDEX laboratories, and this is the SDMA symmetric dimethyl arginine assay.

And this is a useful addition to our diagnostic repertoire. SDMA in many ways is, is quite similar to creatinine in that it is exclusively renally excreted, produced during protein breakdown. Levels of, SDMA correlate closely with GFR on an inverse basis again.

So the higher the STMA, the worse the GFR is. However, a big difference is that, as you can see, halfway down this list of, of, characteristics, STMA is not affected by muscle mass. So all those discussions we've just had about how those thin, poorly muscled cats, we can perhaps be a bit misled with their creatinine does not apply with SDMA.

And there is also some data to support the fact that SGMA may help to diagnose CKD at an earlier. Stage, as you can see, one study detected renal disease on average 17 months earlier than the creatinine tests. Now, I would like to mention that with this particular study, the creatinine levels used as a cutoff for azotemia were more typical lab creatinine levels, so not the 140 value that I use, as I showed you in the last table, but more typically 180 to 200.

If you are very familiar with the Irish range and are using a cut off of creatinine of 140, then you're not going to find SDMA as sort of earth shatteringly revolutionary in your early diagnosis because you will be picking up cases at an earlier stage than if you were just using the standard lab reference range. Since we've known about STMA and information has started to come out, IRIS have updated their guidelines. So for example, as I mentioned a little bit earlier on, if the STMA is persistently over 14, then that is suggestive of reduced renal function.

And even if everything else is fine, we can classify that patient as iris CKD stage one, the non-asotemic catch with CKD. But we can also use it to reclassify patients that are in thin, poor muscle condition. So if you have a cat in iris stage 2 according to its creatinine levels, but the STMA is above, is 25 or higher, then it's we reclassify that as IS stage 3.

And similarly, if your cat is in Irish stage 3 according to creatinine levels, but has poor muscle condition and then SDMA of 45 or higher, it's suggested we reclassify that patient to iris stage 4. So STMA certainly has been helpful. I think it is an advantage if you can include it in your profiles for your preventative healthcare in the older cats, particularly those that are thin and have poor muscle condition.

It's likely to be more helpful in assessing a kidney function in cats with hyperthyroidism, which Traditionally have been very difficult to assess. I, I'm not sure it will be perfect, and we're still awaiting published data on this, but, I think it, it is likely to be more helpful certainly than creatinine, but very much suggested that we use it alongside our existing tests. We're not suggesting that we we throw creatinine out completely.

So let's move on to management now, and general principles of this really are to look at each patient as an individual, to try and see whether there is any ongoing disease, underlying, pathology that would benefit from treatment, for example, bacterial pyelonephritis, for example. There are some general recommendations which we'll talk about, such as maintaining hydration, ideally transitioning to a therapeutic renal. And then for that individual, we need to look, well, what are their main clinical problems?

What can I help them with symptomatically? What complications of renal disease might this patient have? How can I help that?

What can I do also to slow the progression of disease? And very importantly, I think we need to keep close contact with these patients so that really, we're working, very well as a team with the owner, to, to get the best possible outcome. So I, I think it goes without saying really that managing hydration is an important component of, of our CKD management because these patients are very vulnerable to dehydration because they're unable to produce concentrated urine.

But of course, if they do become dehydrated, it's going to have a a domino effect to make things. A million times worse. They will have reduced renal function.

Their kidney function already is is terrible. So that's going to have a big impact on their aotemia, their electrolyte status, their acid base status, constipation also very common in those cats that are just always running a little bit dehydrated as well. So maintaining hydration, doing all we can to do that is certainly, I think going to help.

And there are lots of things that we can consider, a few examples on this slide, but actually I have in my free download section. A guide for owners. How can I encourage my cats to take in more fluids, which is aimed at owners of cats with kidney disease and also owners of cats with, idiopathic cystitis, where we want to increase water intake as well and goes through things to try from what sort of water bowls are preferred by cats.

They tend not to like plastic. For example, also how you can potentially make a flavoured water or broth for your cat, even if it has kidney disease. So for example, you can poach some salmon in a pan of water, you eat the salmon or you give the salmon to your healthy cat or your dog, but the water that is now infused with salmon flavour can be a drink once it's cooled down for your cat.

So there's all sorts of resources there. And then of course, at the bottom of the list, we also have the option of giving subcutaneous fluids to our cats, which owners often very good at doing at home, even for many of my clients that live on their own, they manage to. To get to grips with this technique pretty quickly.

And I have a free download that goes through how to do this as well. The technique that I broadly recommend is to use, a giving set and gravity. So don't try and inject fluid under the skin of a cat, because that is painful and very difficult.

But actually using gravity. Just having a drip bag, giving set and needle, is very, very well tolerated, and 5 or 10 minutes, every day, is, is usually, you know, very effective in these cats, using it as, as written here, a very empirical starting dose of fluids, using things like lactated ringer solution or Hartman's solution, every day or every other day, titrating to the patients. And, and many owners will get very good at assessing hydration in their cat and knowing how to tweak this as well.

So that can certainly be helpful. It's not proven to prolong lifespan in your cat, but hopefully, it has a chance of improving quality of life, particularly in those cats that are vulnerable to dehydration. The most proven treatment, though, in cats in terms of clinical signs and also in terms of progression of disease, would be phosphate restriction, which is typically achieved through a specially designed therapeutic renal diet.

And these diets tend to be protein restricted as well, hence, bundling those together in the title. But as you will probably all know, because it is very well known now, these diets are. Extremely effective at both improving quality of life and extending lifespan in cats with renal disease.

They're especially proven for cats with aotemic renal disease, so that's IS stage 23 and 4. But some data that even the cats in stage 1 will benefit, with a, a lower phosphate diet as well. Hence, some of the companies bringing out these early renal diets, for, for such cats.

All these starts are very clever, multiple modifications. The main one we think is, is of most benefit is the phosphate restriction, but as you can see from the list on this slide, lots, lots of other modifications there as well. But of course, one of the, the big challenges is really how do we successfully transition our patients onto this diet.

And this would be some of my sort of top tips for success, really. I think this is something that clients need a lot of support from, and again, this is where nurses can be incredibly helpful. We need to reassure them that it's, it's OK not to succeed on day one.

It's, we're really thinking of a long term aims here. So it may take 1236 months, or perhaps you may never fully achieve a transition to a renal diet, but everything you can possibly do to achieve it will be of benefit to your cat. So persevere, don't be daunted.

Be prepared to throw away a lot of food unless you've got a handy Labrador living in the house that can hoover up the uneaten cat food. And, make sure that you, you are as cat friendly as possible as well. So resist the temptation as clinicians to introduce a new diet when the cat's unwell in the hospital.

Tempting though it might be, I've just made this diagnosis. Let's give you the right food. If the cat then associates that food with being in the hospital, they're less likely to eat well at home.

So, a softly, softly approach, in general, is going to be most appropriate. So I've got, my, my second poll question here. Really just to ask, from your own experience, what proportion of your renal patients are receiving renal diet as a component of their diets?

So I'm not asking what, how many of your patients are 100% fed renal diets, but what proportion of your patients are at least getting some renal food, as, as part of their diet? Just leave that to run for another 20 seconds or so. And the great thing about these polls is, you know, it's completely anonymous, so don't feel shy about being at the bottom or the top.

You can you can blow your trumpet or or admit, oh, it's not as good as I'd like it to be. OK, so about 2/3 of people voted now, it seems to slow down. So we have 11% of people saying under 25%.

Just under 30% of respondents saying between 25 to 50%. 44% of people saying between 51 to 75%, and 18% of people saying over 75%. Very good, thank you.

Thank you for that. So that's, that's good. I mean, you're, you're clearly, I mean, often I find with lectures, I'm preaching to the converted, obviously I am, because that's, that's pretty good results.

So yeah, so well done, well done for that. The results that, The results that we have from our paper that I mentioned earlier on, also showed something that I think is worth emphasising, which is really the the importance of knowing how much clients do actually listen to us, particularly if we repeat things and reinforce things. As you can see from this slide.

The owner survey that I mentioned, with respect to clinical signs at the start, we asked the owners in this study, whether they'd received a recommendation to feed a therapeutic renal diet, and about 90% of them had. 10% said they had not. They may have, of course, received a recommendation, but forgotten it.

We have to just Take that as a possibility. But those that were aware that they should feed this diet, so that remember the recommendation that perhaps had that recommendation reinforced, as you can see from this paragraph here, were massively more likely to be feeding any therapeutic renal diet to their cats compared to those that said no. No one's mentioned this to me.

And I think the fact that the only reason that that was 7% rather than 0% was because the sort of people that fill in my surveys are very motivated. They've obviously found my website. So even if they, from their memory, couldn't recall anyone at the vet clinic mentioning a diet, they discovered it themselves on their research.

So don't forget how powerful your, your word is. From what's published overall, just out of interest, so you can see how you compare. Well, CKD research studies that typically involve giving free food to people have compliance rates of up to 94%, as low as 46% in, in one study, but basically pretty good.

. The owner surveys that I and other people have done have found 50 to 60% broadly. So I guess similar to to what you guys report. But owner surveys of of prescription diets in general, typically it's been much lower, 10 to 20%.

So perhaps there is an awareness from the owners as well as to the importance in particular the CKD of having this sort of diet. Anyway, it sounds to me like you're, many of you are getting really good results, so well done. So related to the diet, of course, is the, the potential option of phosphate binders, and if you cannot transition your cat to a renal diet, or if phosphate levels stay high in spite of feeding a renal diet.

Then phosphate binders, substances designed to be mixed with the food or given to the cat close to a meal time can definitely be helpful. And there are a number of these available as listed on the slide. Most of the, what I would call veterinary options are.

Calcium or magnesium carbonate products, aluminium hydroxide was released initially through human medicine and has largely been withdrawn. Lanthanum products available through through human medicine still not on the veterinary side currently. And all of these work in the same sort of way.

So, they bind the phosphate in the food, prevent it from being absorbed, so it's excreted in the faeces. So all you're doing is really limiting phosphate available to be absorbed. And so therefore, blood phosphate levels are only going to come down, according to renal excretion.

And if your cat's got Very severe renal disease. It can take several months for you to really see any reduction, or significant reduction in their phosphate levels. So hence the suggestion on this slide to not monitor your phosphate levels more frequently than every 6 weeks, having changed, your intervention regarding phosphate binders, for example.

And just be careful with calcium containing products to not use obviously in a hyper calciumic cat, which is not commonly found in cats with CKD, but you do sometimes find, but also not if you were using a calcitriol therapy either. You would need to avoid the the calcium containing products. The IRS charts of staging for kidney disease, now presented in this slide with the target phosphate levels according to each iris stage.

So, Iris several years ago started to tell us, well, we really ideally want to have the blood phosphate levels at the bottom of the reference range, if at all possible. But as you can see, we have slightly different targets for the different stages of renal disease, not because we really want these cats with more severe kidney disease to have higher phosphates, but just really to be realistic. So as you'll see on this slide, on the right hand column, we've got the target phosphate levels.

Ideally, you want to keep it less than 1.5, but if you have a cat with stage 4 renal disease, if you can keep the phosphate less than 1.9, you're doing a brilliant job.

And that's important information for you to know because many lab reference ranges for phosphate, are, are higher than those target phosphate levels. So typically a normal lab reference range for phosphate would be between 1 and 2.5, and obviously having a phosphate of 2.5 if you've got kidney disease is really bad news.

But the reason they're that broad is because young animals, when they're growing their bones and muscles will have high phosphate, phosphate of 2 is quite normal in a kitten and fine. So that's, that's where the lab reference range comes from, but it's not appropriate for your CKD patient. And we should assume all of our CKD patients will benefit from phosphate restriction.

Another challenge with our kidney cats is often that they have poor appetite. So again, this can make transition to a new diet very difficult. My approach in this situation is really to think, well, what are the possible reasons for this cat's poor appetite related to its kidney disease?

Is it dehydrated, for example? Has it got low potassium levels? Is it anaemic?

What can I sort out? What can I help with? Because many of these things, we can actually correct.

Chronic pain, not necessarily associated with CKD in general, but more thinking of these older cats that have arthritis, as well as kidney disease. So my first approach is really look for things that I can fix, fix what I can fix, give some general advice to the owner. So this would be the sort of advice I would give to an owner, which is really just all your normal nursing tactics to hand feed the cat, maybe Mash up the food a bit if the cat's got bad teeth, raising the food bowl can help if you've got arthritis.

Also resisting the temptation to overwhelm the catch with every cat food available in the supermarket and every prescription diet possible simultaneously because that generally has a negative impact as well. So all these things that you'll be familiar with, in general, when, when they're trying to tempt an anorexia cat very much applied to your CKD cat. And then beyond that, we have the option of some symptomatic supportive treatments.

So for example, antiemetic therapy, Moropotent, of course, can be very effective. And on a non-licensed front, a good option often would be mirtazapine at the bottom there as an appetite stimulant, which also does have antiemetic effects. So it has a combined effect and quite a low dose frequency every other day dosage recommended for cats with CKD.

I will usually start on a 1 milligramme dose, and you can increase to 2 milligrammes if need be and if that's well tolerated. And this often is extremely, extremely helpful. Anacids, some cats, will respond to, so that also is an option.

Certainly in the past, I used a lot of famotidine, but I think there are increasingly better options through, through the other medications I've mentioned. And another appetite stimulant that you may be familiar with would be cyproheptadine or peractin. So that also is an option.

Hypokalemia, I briefly mentioned, was one of the potential causes of poor appetite in cats, and, and it's certainly a fairly common electrolyte disturbance in cats with CKD. So it's important to be aware of it. In its most severe form, it can cause this so-called ventroflexion of the neck, the top picture.

Of the cat that can't hold its head up, and this is because if your potassium levels are very low, it actually causes muscle necrosis and very severe muscle weakness. And cats don't have a mal ligament helping to hold their head up. It's only held up by muscles.

So if they have severe muscle weakness, they, they can't hold their head up. But most cats with CKD actually, the hypokalemia is, is more borderline and you'll just have a cat like the one in the bottom picture who, yeah, I just don't feel very well. So remember to look at potassium levels in your patients.

This is something we can treat, so various options available. If the cat is having fluids intravenously or subcutaneously, then adding potassium chloride is often an easy thing to do. But orally potassium gluconate preparations are usually the best tolerated.

And of course our renal diets have additional, potassium in them as well, which helps. And also, I, I mentioned on the last slide, but I didn't actually say this out loud, but a low potassium levels actually has a negative impact on renal function, actually causes tubular acidosis and worsens renal function. The good news is if you correct that hypokalemia, actually will help your renal function.

So this is really something to keep an eye out, out for. Another example of a severely hypokalemic cat, this is actually a patient of Andy Sparks, and when I was working with him a long time ago, this poor cat Emma, you can see is interested in her surroundings. Her ear position is saying, yep, I'm listening.

But she is so weak, she cannot even stand, and she certainly can't raise her head. But having had some fluids and having had some potassium, feeling very much better, this is, this picture was taken about 48 hours later. She still has severe CKD, but we've now made her quality of life very much better.

Definitely need to supplement these cats if their potassium falls below 3.5. I tend to start even actually once it falls below 4.

I like potassium between 4 and 5 if possible. And the renal diet is really the ideal way to go in terms of long term maintenance and just be careful with things like giving too much fluids, particularly if you've not put any potassium in the fluids can really flush out that potassium. And some medications, of course, like diuretics also can contribute to hypokalemia.

High blood pressure, we mentioned earlier on as as being important to measure in all our older cats because hypertension is quite common in our older cats, and it's particularly common in association with CKD where perhaps up to 60% of our CKD patients are hypertensive, maybe typically a third. So a significant chunk of our cats that are affected and there's no link between the severity of the renal disease and likelihood of high blood pressure, so we just need to get out there and check blood pressure, ideally at least twice a year, and manage it and current recommendations. Are to treat it if the blood pressure is persistently over 160 systolic, or if it's over 160 on a single occasion, but you can see evidence of target organ damage such as retinal detachment, then start treating straight away.

There is, as you'll know, a licenced treatment for systemic hypertension, which is Amidip amlodipine, which is often extremely effective. Eintra Telmisartan, which you'll be familiar with as a treatment option licence for proteinuria associated with CKD, either just now or very imminently, will have a licence for management of hypertension as well, although that will apply to a different concentration of cement. It's going to be 10 milligrammes per mL that is licenced for hypertension, and I believe that stocks of that product are only going to start to appear in September onwards with the official launch being the new year.

So you may need to wait a little while for that, but that certainly will be also an option available for management of hypertension. ACE inhibitors do have an impact on reducing blood pressure, but typically much less potent. It can be used in combination with amlodipine very safely though.

And that brings us neatly on to talking about proteinuria. Why are we interested in this? Well, there definitely is information that tells us that having proteinuria is bad.

It has a negative association with your survival. And we know that also presence of protein in the renal tubules is damaging to the kidneys. So if we do have renal loss of protein, the big Concern is that that's going to contribute to progression of disease, and further loss of nephrons, and this is why assessment of proteinuria is recommended, and management is also recommended.

And the current recommendations are that we firstly, if at all possible, assess cysto samples for proteinuria, so we're not having to worry about protein contamination from the lower urinary and genital tracts and that we use a urine protein to creatine ratio to assess significance of proteinuria. Although that top picture of a dipstick shows a very strong positive and that was from the sample on the right, which, as you can see, very frothy, very proteinuric. Many cats with significant proteinuria.

It's quite subtle and it's, it just is not picked up on a dipstick. So really you need to do a UPC. And the current Irish recommendations are to treat cats with the UPC above 0.4.

Having said that, there has been discussion of treating cats with borderline proteinuria. That's UPC between 0.2 and 0.4, and that's partly the rationale for that is based on this paper from Hattie Syme of the RVC paper you can see actually quite a number of years ago now.

But this was a study where she looked at the survival, the outcome of cats with CKD, and they were grouped on day one according to the UPC results, and incidentally, the UPC was from a free catch urine sample. But essentially, Grouped into three groups, those in the red line were had a UPC less than 0.2, so they were nonproteinuric.

Those in the blue line had a borderline proteinuria between 0.2 and 0.4, and those in the grey line were proteinuric, UPC greater than 0.4.

And we have a chart here, which is a survival chart. The Y axis shows the proportion of cats alive and the X axis shows survival in time in days. And so at the start of the study, all of the cats in each group are alive, hence, the proportion surviving is one for all three groups.

But what you can appreciate is that as time goes on, the cats in the the grey group seem to be dying the most quickly, with the cats in the red group doing the best. So, evidence here again. That, you know, proteinuria is associated, has a negative association with the survival and that those borderline proteinuric cats also do significantly worse than the non-proteinuric cats, which has been used as rationale to treat these cats rather than just waiting till the cats are overtly proteinuric.

So we have the ACE inhibitors, thalmisartan Cementra, which is a a relatively new medication or ACE inhibitors like Benazepril, which both suppress the renin angiotensin aldosterone system and are, are both have been shown to reduce proteinuria in cats with CKD. Also both shown to improve quality of life in these cats as well. But overall, unfortunately, not great data to really support the fact that these cats actually live significantly longer.

There are still studies underway to try and, I think, demonstrate that benefit. You know, often we struggle to get studies that are as large as the human equivalent options. So it's, not always easy to get enough power in your study to show a benefit.

But, certainly not as dramatic results as as we we might like. Could you favour Telmisartan versus Benazepril? Well, Telmisartan, obviously the more recently launched products, and it does have a more targeted mode of action, which has some potential advantages.

But there's no proven evidence that's published at the moment that your cat on cementtra will do better than your cat on Benazepril. So certainly if you've got cats on Benazepril and they're stable and doing well, don't change them. There are potential adverse effects with these, these medications, whether it's an ACE inhibitor or, or an ARB.

So we should monitor these patients closely for, problems with their blood pressure, inability of their kidneys to cope with their, the altered renal blood flow following. Use of these medications. So if there is a dramatic worsening of azotemia, then you might find your patient is unable to tolerate this medication.

But most cats, as long as they're not dehydrated and as long as they are stable, actually do, do very well on these medications. And of course, there is much more information in the guidelines I mentioned at the start on all sorts of things I've sadly not had time to go into just now. So please do have a look at those if you're interested in general in learning about these.

And finally, really just an emphasis on the checkups, because, as I said a little bit earlier on, I think the the outcome is greatly enhanced by having that good team relationship with the carer, and this often can be achieved through regular checkups through which you educate your owners, support them in the challenges that they are finding with their particular cat. And of course monitor the cat closely. So, really encourage you to do that.

And my book goes through, checkups as well and hopefully it's the ideal support resource for your clinic and also for your clients. So apologies for taking up a lot of your, your time, whether it's evening or or daytime. Thank you again for choosing to listen.

And if you do have any questions, I'd be very happy to answer them. Thank you. Thank you so much, Sarah.

That was a fantastic webinar, very informative. We have questions pouring in already, so, I hope you're ready. So, as I mentioned earlier, anyone who's listening as well, if you do have any questions, please do, pop them into the Q&A box and we'll get through as many as possible.

OK, so a couple of questions. So the first question, my own cat has mild CKD and is on a renal diet. She loves dental biscuits and I believe it helps her dental health.

Is it OK to use this as a treat? I'm sure it's, yes. I mean if you were one of my clients, I'm, I'm sure I would be saying yes.

I mean it it we have to look at the whole picture. I, I strongly believe in terms of quality of life and there are other benefits to. You know, potentially helping with dental health.

Dental health also, I, I, I could have mentioned if I had more time. There is more and more data to suggest that dental disease has an impact on perhaps causing, perhaps exacerbating CKD that's that there appears to be an association there. So I think maintaining den.

Mental health in these older patients is really important. So, of course, from a, a diet perspective, if you can get, you know, as close as you can to 100% of the diet, being a therapeutic renal diet, then you're doing a fabulous job. But I think if it's 90% or 95%, you are doing an outstanding job.

So, yeah, continue as you are. Fantastic. Thank you.

And that's interesting. We have another question here about dental health as well. So, you mentioned cats with bad teeth in the presentation.

My question is, is an intervention under general anaesthesia? So, for example, the necessary dental treatment out of the question for a stable patient with renal insufficiency? Excellent question and I would say no, it's not out of the question.

And in fact, Depending on the cat, I, if there is what I would call significant dental disease, as in disease that I would want to manage, in the normal ways, as in GA, etc. Then even if the cat has CKD, I, I generally I, I encourage the clients to go for it. Sooner rather than later, if the cat, of course, is stable as you described, because the worry always is that, you know, as time goes on, firstly, that that dental disease will get worse, but also the renal disease will get worse.

So if you delay it, you may end up in a situation where you ultimately are unable to do it because it does become too, too risky. So I would not preclude it just on the basis of the cat having CKD. What I would suggest though, in these cases is that again, depending on the patient and the severity of the renal disease, the sorts of things that are worthwhile would include admitting the cats, perhaps.

The day before, it's dental, doing a quick blood panel to check for any electrolyte abnormalities that might benefit from being corrected, putting a cat on some maintenance fluids to ensure optimal hydration. We don't want to over hydrate our patient, but we definitely want them optimally hydrated. Avoid non-steroidals in the perioperative period, also try and minimise medications that might have a significant impact on lowering blood pressure.

So things like ACP. A very low dose is generally safe, but you might want to perhaps avoid that and use a benzodiazepine pre-med, instead in your cat or just an opiate, pre-med in your cat, for example. And then if you can monitor the blood pressure of your patients through anaesthesia and be able to, intervene if, if the cat's blood pressure starts to fall.

By upping the fluid rate, all these sorts of things will have a positive impact. Of course, there are always cases where, you know, you do all these things and it and sadly, it doesn't work out, you know, the cat has complications or or their renal disease is unfortunately worsened in in the sort of post-op period. But I think with careful advice to the owners and counselling about that as a possibility, I would still really encourage in general, for them to have for the cat to have these procedures, sooner rather than later, particularly if they are, if their renal disease is stable, because that hopefully is the best chance of, of maintaining quality of life in the long term.

Excellent advice and very, very detailed answer. Thank you very much, Sarah. So I have a couple more questions coming in.

So, in, in a multi-cat household where the CKD cat needs to get, or needs to be on a renal diet, in this case, iris stage 2, how detrimental is it for the other cats, to be changed over to a renal diet if feeding separately is difficult or not an option? So if, if the other cats are adults or older, then I would say, you know, the diets, should be absolutely fine for them as well in terms of, you know, it, the phosphate restriction, phosphate restricted diet for, for an older adult or older cat, is not gonna cause problems. Probably the main issue would be if you had young.

Growing or pregnant animals that had high protein requirements, that would, that, that would pose some problems. And you would need to try and find a way of, of feeding the cat, for example, the, you know, the, if it was a kitten, you know, perhaps feeding it on the work surface where that cat with CKD is probably not going to be able to jump up anymore. Those sorts of solutions.

Obviously the microchip control. Food bowls are fabulous, but, but very expensive, perhaps as an option. So, but for most adults or older cats, I would say your renal diet is fine.

The only sort of potential adverse effect, just to be a little bit aware of is that they tend to be high in fat. So if you have overweight housemates, sadly, that it might exacerbate that a bit. Thank you very much.

We have a question here, someone's asking which phosphate binders include calcium? So I think probably all of the veterinary ones have, calcium in to some extent or other. A packet is calcium carbonate.

The more sort of modern ones, if you like, pronephri and renate. So proneph is a B back product, a renates made by VELs, they contain a mixture of calcium carbonate and magnesium carbonate. So relatively speaking, less calcium containing than ippacotine.

But, it's a shame that the, the one lanthanum containing products, renals in which, probably many of you will remember, it was a Bayer product, sadly, disappeared from the market, and I think disappeared not for reasons related to its safety or efficacy. I think it was due to ingredients allowed by the EU formulators. So maybe there were, there are, there's mileage, you know, a future lanthanum based product reappearing.

Also, if you can get your hands on aluminium hydroxide, for example, all cap capsules, which tend to be very cheap and cheerful. That often is an effective binder, and of course, it is calcium free, does have aluminium in it and potential for side effects at high doses, but at your typical doses you'd use as a binder is often very effective and, and very safe. Wonderful, thank you very much, Sarah.

A question here from Richard's asking that what PCV would you recommend using D Python? So the typical cutoff that's suggested for starting. An erythrocyte stimulating agents such as Dretin and would be PCV less than 20%.

And the rationale for that is that some cats, probably less than, less than 10% of cats receiving Drein, but maybe a third or even more of cats on the standard Eperin will produce antibodies to the synthetic erythropoietin, which ultimately means that The synthetic erythroin doesn't work, but also their own endogenous erythrorein stops working as well because of these autoantibodies, and that's a situation called a pure red cell aplasia. So this is an acknowledged side effect and that and that, as I say, is why people tend to hold off using any of these erythrocyte stimulating agents until they're clinically needed and and that is thought to be PCV about 20%. But I think use your judgement as well, you know, look at your monitor your patients.

If you can see a clear downward trend and the patient is deteriorating, perhaps intervene sooner, if it appears to be coming down very slowly, perhaps you can monitor and not introduce, as As, suddenly, there are some nice papers on use of, ESAs and if you do have a particular interest, feel free to email me and just ask and I can, I can send you there's certainly a really nice journal of feline medicine and surgery review paper on it that I could email you. Excellent, thank you. And Sarah's email address is in the chat box.

If you would like to to find that there, it's Sarah at vetprofessionals.com. And if you go into the chat box, you should be able to see that.

Just a couple of final questions then, going back to our earlier question, we have, how about, thyroidectomy and CKD stage 2AT? Is general anaesthesia safe? I think I would apply the same broad logic to thyroidectomies as I would to the dental question we talked about earlier on.

So, definitely wouldn't completely rule it rule it out. But, there are, you know, additional, I suppose, additional concerns with the thyroidectomies are always going to be, is there going to be a further deterioration in, in renal function following, achievement of your thyroidism, and that can be unpredictable. However, still, the, the current consensus is that, you, it's better if you can treat the hyperthyroidism optimally, that will be better for the kidneys as well as for the thyroid.

So I think leave that door open, definitely and look at the individual cat. Certainly, really long, long, long term medication also has its downsides. So, if you have a nice palpable goitre and, you know, you know, a competent surgeon, it could well be a nice straightforward way of at least resolving one of the conditions.

Great, thank you very much. Just a final question now then, there is a paper evaluating using meloxicam in half dosage in cats with CKD. What's your recommendation in cats with CKD and osteoarthritis?

Yes, excellent, excellent question. So I, I, I use it, is the short answer. And I'm reassured by the studies, including the, the one that you mentioned, which, for those of you that, that are perhaps not familiar with it, was a study looking at, renal function over a period of time, in cats that had kidney disease alone.

And we're not on meloxicam, versus those with kidney disease in LA that were on this sort of half dose of meloxicam versus those with osteoarthritis that were on Meloxicam but didn't have kidney disease and a control group. Basically, what they found was that meloxicam used in that way, so these in stable, non-dehydrated cats at say roughly half the label dose. There was no negative impact on renal function over that.

I think 6 month monitoring period. And certainly clinically, quality of life can be massively helped for these, these poor cats that are struggling with their OA. So if I do have a cat where I, I think really it would benefit from analgesia.

Then, firstly, I do all I can to make sure that cat is optimally hydrated. I would not use any non-steroidals if I think my patient is dehydrated, but if they are normally hydrated and I think they are stable, then, they are a case that I will consider using meloxicam in. My, my typical way of doing it would be for most patients, to start on the label dose.

So the, the standard, dose that you do syringe according to their body weight as you would do for a cat that didn't have CKD, use that dose for 5 to 7 days, really just to determine efficacy. And if it is effective, then try and gradually bring down that dose notch by notch, to the lowest effective dose and that typically is about half the label dose. And, meanwhile, just do all you can to again sort of encourage and support hydration, so that it's as safe a therapy as possible.

I do think it, it, it, it can be extremely helpful. And another thing that is also being really useful as a newish product to the market is, the diets, the, the Hills KD mobility diet, which, you may well have used, but I've found this is often a very well accepted diet and obviously orientated towards joints as well as kidneys, so that too can hopefully have a positive impact on, on everything. Perfect, thank you so much for that, sir, and thank you for an excellent webinar tonight.

It's been thoroughly enjoyable. And thank you everyone for, for listening. If you wouldn't mind, there will be a pop up with a feedback form that only takes a minute or two to fill in.

If you could fill that in for us, that would be hugely helpful. Thanks once again, Sarah. Thank you very much for that webinar.

Thank you all too, thank you. And we'll see you on another webinar soon. Thanks, good night.