Kidney Failure and Disease


Kidney Failure and Disease

Kidney Failure with no symptoms

Question: Hi Doc: I brought my 18-20 year old cat, Romeo (male, neutered) in for a check up last week and we ran a blood profile because of his age. His BUN was 103, his CREAT 8.4. GLOB was 5.14. All else normal (alb, alkp, alt, amyl, ca, chol, glu, phos, tp).Obviously, results are very troubling and indicative of kidney insufficiency. Romeo has NO symptoms of kidney insufficiency. He is active, a good eater, fun-loving, coat shiny,not lethargic, happy. The only symptom I have noted is drinking a lot of water and outputing it too. My questions are....does this seem right? That he would show NO symptoms and still be that sick? Could it be something other than kidney? What else should I do? Hemocrit was almost normal as was urinanalysis. I put him on KD which he DOES NOT like and that is a problem as he is eating much less than normal (it is mixed with his old food). HELP....I love this cat, and as you know, just had to send Snowflake, another of my senior cats to heaven in August. I don't know if I can go through this again so soon. Thanks in advance. Ellen

Answer: Ellen We see some older cats whose kidneys have apparently been failing for some time who act normal despite very high BUN and creatinine levels. With the levels being this high, you either need to confirm that the bloodwork was correct (we have had three or four instances in our practice of lab work that was submitted incorrectly (our fault) or reported incorrectly (lab's fault) so it is worth rechecking lab work when it doesn't seem to fit the clinical picture. Drinking a lot and urinating a lot are signs of kidney disease, though. Diabetes is the other strong possibility but the lab work should have shown increases in the glucose levels if that was the case. It is much more important that Romeo eat well than that he eat a diet made for kidney disease. Please let your vet know that he is not tolerating the diet well. There are other alternatives he might like better (Purina NF (tm), Waltham's moderate protein, low phosphorous diet). If he doesn't like any of the specialized diets it would be better, in my opinion, to let him eat what he wants -- but please discuss this with your vet, too. Using a phosphate binder with his usual diet would help a lot, if a specialized diet is not possible. I would strongly advocate subcutaneous fluid therapy for a patient with these BUN and creatinine values, even if he or she didn't seem bothered by them. It is better to get these to reasonable levels before he notices that he is sick, if possible. It is often possible to maintain cats with insufficient kidney function for very long time periods using a judicious mix of diet, medications and fluid therapy. There is a link to a good web site on chronic renal failure in cats on our links page. Mike Richards, DVM 1/22/2001

Kidney failure

Question: Dr. Mike. My cat, Emily, 16 this month has CRD. Her symptoms only became evident 1 1/2 wk ago. I have several questions about her treatment. She is on KD diet and Tumil-K gel. My vet mentioned sub Q fluids may be needed in the future. I apologize for not having the levels of her tests for you, but my head from spinning from the news that this is a fatal disease and I just stopped writing things down trying to digest the hard facts. As I have always been so diligent with her health/diet I really expected to have her w/me 19-20 yrs. Eight yrs. ago Em was rushed to an emergency clinic. After a diagnosis of urinary tract infection the vet said quite casually that she had chronic kidney disease. I asked what that meant and he said it meant her kidneys were very small for a cat. I told him I had her on a diet of Hills Scientific and he said that was good for her and that was the end of it. I was never told that this was a fatal disease or offered any advice on treatment. As Em seemed fine after that, and he seemed to casual I did not consider her condition a problem. 1st question...was the disease unknown to be fatal then, or chould the vet, considering her age, overall health and very chubby physic have thought it was really nothing to worry about at that time? My second question is my concern over my vet not putting her on fluids immediately. I will ask him this question Mon. but I would like your opinion also. He has been our vet for 8 yrs. now and I trust his judgement but as I knew nothing about the disease before I have been doing alot of research and this seems like a very common approach. As I said, I do not have figures to give you but I can tell you her condition. She is lethargic, not eating, was drinking tons of water (but that seems to have decreased), moving away from me and clearly uncomfortable. She is weak to the point of being unsteady on her feet. She ate the KD, diluted w/her regular food the 1st day but has not since. I have mixed it w/tuna water, warmed it but no go. For 2 days she would eat nothing, even her regular. Today she ate from my finger, a very diluted mixture of her food w/KD. My last question, with this diet and the supplements how long should it take to see any improvement or sign that this is even helping her? Am I being too impatient? Sorry for this very long letter, I visit your site often and find it so helpful as I work for a rescue group and often need ideas/help. I will be asking my vet these questions but would really appreciate your input, my absolute concern is to be able to care for Em the best I can, she's been my joy for many years and I must do right for her. Thanks, Cindi

Answer: Cindi- I think that it is best to give subcutaneous, or intravenous, fluids in patients who have clinical signs of illness resulting from deficiencies in kidney function. It is a much harder choice when we discover signs of kidney insufficiency on a routine examination of an otherwise healthy cat, or in blood work that turns up another illness that seems to be the current problem. In these patients we often try dietary modifications such as changing to diets that are helpful in kidney insufficiency, supplementing potassium, using calcitriol or phosphate binders and closer monitoring of the cat's health. Usually, there is some improvement in activity levels, attitude or other behaviors indicating that this approach is helping, within a few weeks. If not, it would be best to consider additional therapy. I am pretty sure that most cats over ten years of age have some degree of compromise in kidney function. Most of these cats will do fine, without treatment, for several years. At some point, one of the functions of the kidney will become deficient enough to cause problems. For some cats this will be potassium regulation problems, for others azotemia (inability to detoxify the blood adequately), weight loss or other sigs of kidneys that are just not functioning well enough. Veterinarians, including me, tend to refer to this condition as kidney failure when it really is more accurately described as kidney insufficiency. The kidneys need help to do their usual jobs and if they get the help, they will continue to meet the body's needs for a long time. Our personal record for a cat that came in to the office in a crisis situation from kidney insufficiency was eight years of good quality life after this initial episode. We have had a number of patients in which we discovered kidney insufficiency by accident who lived much longer than this after the initial realization that there was going to be a chronic problem with kidney insufficiency. The things that help the kidneys are these: 1) control phosphorous levels in the diet, through the use of low phosphorous diets, calcitriol supplementation and/or phosphate binding agents, 2) moderate protein levels in the diet, 3) supplement potassium, 4) use anti-hypertensive agents (we like amlodipine (Norvasc Rx) as a first choice but use enalapril (Enacard Rx) in some patients), 5) do what you can to get more liquid into the diet by switching to canned foods, encouraging water intake with a source of running or moving water, 6) when it is apparent that a cat can not maintain adequate hydration, or needs enough fluids to induce diuresis, use subcutaneous fluid administration. I strongly prefer that my clients learn to do this at home, so that it can be done daily when necessary and so that it is less stressful to the cat, but if intermittent therapy at our office is all that can be done, we use that approach, 7) when anemia becomes a problem, consider using erythropoietin supplementation. This should be put off until absolutely necessary, unless a cat origin source of erythropoietin becomes available, which may happen. The present products are human origin and cause antibody formation against this hormone in some cats, which is a really serious complication of therapy. 8) for younger cats, kidney transplant is possible, although it is expensive and does not always work out well. Eventually kidney insufficiency will lead to a situation in which the kidney have truly failed and this condition becomes fatal. However, this decline in function may take a very long time, if you help the kidneys out, allowing them to do less work and making it possible for them to meet the body's needs in this manner. I think it is still reasonable to hope for Emily to live 19 to 20 years. There is no guarantee but there is also no reason to give up and passively accept a poorer prognosis for longevity, either. Mike Richards, DVM 11/26/2000

Renal amyloidosis in Abyssinian

Question: Dr. Mike: I have an Abysinian cat named Bobby. He was born late February of this year, he has just been diagnosed with kidney failure. He had bloodwork and most recently an ultrasound which somehow confirmed he was only able to utilize 33% of his kidneys. (His urine is not concentrated..) My question has to do with treatment. My vet says just wait and re-test. I want to be more aggressive. What do you think? Have you ever heard of this in such a young cat? Is it a breed thing? My girlfriend owns two of his litter mates and has offered a kidney for a transplant. We live in No. California and I understand UC Davis does perform this procedure. I also read some of your online articles? What are the risks to both kittens? What about food? I've been feeding Bobby 4-5 times a day really small bites to help in processing - what else? I love Bobby and want him to be around... Thank you.

Answer: J- Renal amyloidosis occurs in Abyssinian cats as a congenital disease. In Siamese cats this disease is thought to follow family lines and is therefore suspected to be genetic in origin but I do not know if this is the case in Abyssinians. This is a disorder in which excessive production of amyloid occurs somewhere in the body and it damages the kidneys as they try to filter it. This disorder can occur due to infections, such as feline leukemia virus (FeLV) or feline infectious peritonitis (FIP), so looking for a primary cause is a good idea. If amyloidosis is present, a kidney transplant is not going to help much over the long term, because the production of amyloid continues to occur and the new kidney will become damaged over time, as well. There are other potential problems that may have lead to the current state where the kidney function is insufficient. Trauma to the kidneys, blood clots that damage the kidneys, congenital disorders other than amyloidosis, glomerulonephritis, infections of the kidneys, and other problems can all lead to damage to the kidneys at an early age. It is possible for Bobby to compensate for a one-time insult to the kidneys, even if it damaged a major portion of the kidneys, and to live a pretty normal life. It would be a good idea to try to rule out viral causes like FeLV and FIP and to look for any other treatable underlying cause at this time. The first step in the process of deciding what to do is to try to identify the underlying cause of the kidney failure. I think that it would be best to ask for referral to the veterinary school, or at least an internal medicine specialist, as this stage. Identification of the underlying problem may require biopsy of the kidney at some point, but there are other tests to consider first. A protein:creatinine ratio (done with urine) helps to confirm that protein is spilling into the urine, which is a strong indicator that glomerulonephritis or amyloidosis is present. Ruling out possible causes can be done by physical exam and testing for things like FeLV. If this does not provide an answer, then kidney biopsy would be helpful, because glomerulonephritis tends to respond to treatment (the progress of the disease can be slowed) and cats with this condition may do well with a kidney transplant. Amyloidosis tends not to respond to treatment and cats with this condition are not good candidates for a kidney transplant. Getting to the point where you know which problem is present allows a better decision making process. There is not enough research to tell you the best diet for cats with glomerulonephritis and amyloidosis but the prevailing opinion among kidney specialists seems to be that moderate protein restriction and low salt content in diets are good goals. The diets made for kidney failure, such as Purina's NF, Hill's k/d and others are satisfactory to meet these goals. As kidney failure progresses, the low phosphorous content of these diets is also helpful. Controlling hypertension (high blood pressure) is a good idea, since many cats with kidney insufficiency, particularly with glomerulonephritis, will have high blood pressure. Fluid therapy is often helpful. There is a good link on our link page for cats with chronic renal failure. I really do think that it is best to be more aggressive about finding out what is going on and then in treating the problem, so do consider asking for a referral to an internal medicine specialist or the vet school at UCD. Good luck with this. Mike Richards, DVM 11/6/2000

Kidney problems and dry vs wet cat food

Question: Dear Dr. Richards, Your publications are very informative and your website has helped me w/questions regarding one of my cat's skin problems. We adopted two Malaysian stray cats while living in Kuala Lumpur who are now almost 7 years old. My question regards the merits of dry food over wet. Our vet here in Singapore (a Canadian trained in Canada) suggested feeding only dry food when we moved here almost 3 years ago and recommended ANF and MaxCat. I am feeding a mixture of both of these plus some wet (canned food) in the morning. My friend (from Belgium) brought her two cats from Belgium and adopted 2 Singaporean strays which stay mostly outside. We use the same vet and she has been feeding her cats mostly dry food. She recently had to have her female Singaporean cat put down due to kidney problems and I think she blames the vet for recommending only dry food. (She told me that the Belgium vets recommend only wet food - no dry for cats there). Both ANF and MaxCat claim they are formulated for optimum kidney health. I hope the dry combination plus wet food (and having water available all the time) that I have been feeding my cats is good for them. (They also get treats of cooked chicken and fish and my male loves honeydew melon). Do you have an opinion? - I don't want my cats to have kidney problems. Thanks, Cecelia

Answer: Cecelia- I am not aware of any studies suggesting that dry cat foods cause kidney problems, nor does this seem to be the case based on our patients. However, there are studies that suggest that feeding wet food can help in reducing the rate of deterioration in cats that do have kidney insufficiency/failure problems. The reason for this appears to be an increased intake of water in the food, since the moisture is not removed, as it is in dry foods. It seems logical that at least some cats would benefit from eating wet foods rather than dry foods, from the standpoint of kidney disease. But like most nutritional things, it is probably true that wet food can lead to some other problem, balancing out the beneficial effect in kidney disease. An example of this is an early indication that cats fed canned food are more prone to hyperthyroidism, for instance. In all honesty, I do not think we know enough about the nutritional effects of these products to declare a clear advantage to either product. Like you, I feed my cats a mixture of dry and canned wet foods. Mike Richards, DVM 10/9/2000

Kidney problems cats Question

Dr. Richards, I have a mixed breed cat, Genny, she is neutered and a strictly inside pet. I have had her for approximately 12 years and when I took her in for yearly check up my vet ran some bloodwork on her since he was going to clean her teeth; we have never had blood work done before on this cat so I have no other test to compare her results with. My vet has advised me that the test came back showing my cat has kidney disease and he feels that we have caught it early. My vet is trying to reassure me that we'll be able to control the disease with special food (I think it is Hill's Prescription Diet) and if this food does not work there is another food that is a bit stronger (I'm sorry I do not know the name of it.) He also said I will need to bring her in for frequent check ups. My questions/concerns are: 1. Is this a curable disease? 2. If not, can my cat continue to live a long life with this condition? 3. If the food is the only option I have right now, how long before we will see improvements in her bloodwork? 4. How often should any testing be done to monitor her kidneys? 5. Is the blood test the only testing that should be done to diagnose and/or monitor the kidney disease? 6. Is there anything I can do to stop further damage to her kidneys? 7. Is there anything I should watching for - for example: changes in her drinking, urinating, any body changes or reactions, etc.? 8. Is there anything else that I can give her to "build up" her kidneys? 9. If the food does not work do I have any other options (for example: medications)? Dr. Richards, I appreciate your time and any information that you can provide me, for I am trying not to over react, but I am quite worried and want to do whatever I have to keep my kitty healthy and happy! Sincerely, Dianne

Answer: Dianne- As cats age many of them develop renal insufficiency, which is a decrease in the function of the kidneys to the point that they are not able to adequately do their job. This happens because kidney cells die and are not replaced. To compensate, the remaining kidney cells learn to do their job better. Fortunately, it is possible to slow the rate of cell death and to encourage the other kidney cells to function better, making it possible to slow the progress of the disease. Still, the disease is incurable and will eventually lead to the death of the patient over time. We have managed cats with renal insufficiency for as long as ten years before that happened, though. Although that is an exceptional case, many cats live several years with good quality of life. If the signs are very mild, we will sometimes rely on diet alone. When we do this, we ask owners to let us check lab values after 2 weeks to one month and then every three to six months. We are not really looking for improvement, we are trying to make sure we catch any deterioration in kidney function quickly. Many cats do actually show improvement in the kidney related blood work with dietary control alone, often by the time we do the initial blood work. The things that help prevent loss of kidney function are adequate hydration. Feeding canned food is preferable to dry food due to this and I think that going to subcutaneous administration of fluids early in the disease process is beneficial. Medications to control blood pressure are sometimes necessary and may be helpful even when increases in blood pressure can not be documented. Potassium supplementation is helpful in many cats. While its use is controversial, calcitriol administration seems to make many cats feel better. Phosphate binding agents (such as Amphogel tm) are helpful but less necessary when using a low protein/low phosphorous diet. Figuring out when to add each of these medications is difficult because each patient is different but all may be necessary at some point. Making sure that complicating diseases are not present is a good idea, too. The most common one is hyperthyroidism, which should be tested for if there is weight loss, especially if it is accompanied by an increase in appetite. Monitoring urine specific gravity is helpful. I like this test a lot when it is easy to get urine, because it helps to determine how well the kidneys can concentrate urine. Keeping track of Genny's weight helps a great deal, too. Weight loss can actually be good for patients with kidney problems but if it is occurring too fast it can be a sign that additional therapy is necessary. It is critical for cats with kidney problems to drink water on a regular basis. A great increase in thirst often indicates that the kidney situation is becoming unstable again and when cats with kidney disease stop drinking they need to be checked to see if the kidney disease is getting worse suddenly. I don't know of any food supplements other than those mentioned above that are helpful. Potassium administration seems to help even when potassium levels are in the normal range, so if it isn't too much trouble (some cats hate the potassium preparations) it would be worth considering supplementing potassium. There is a very good web site for chronic renal failure at Hope this helps some. Mike Richards, DVM 7/24/2000

Kidney Failure - daily fluid treatment

Q: Doctor, Please advise. My friend has a 9-year-old female cat (Tiga) who has recently been diagnosed with kidney failure. Her "mom" gives her fluid IVs on a daily basis. Tiga seems to be happy, sometimes playful, although her weight is still low. Is there an average life span for a cat once it begins fluid therapy for kidney failure? I would welcome any advice or thoughts you have re this condition. Thank you, B. G.

A: B- I think that daily fluids is very helpful for cats with compromised renal function. I don't think I can give you an average lifespan for cats once fluid therapy is necessary but I can give you some idea of our experiences with this. We have had several cats who lived for longer than 5 years with frequent, or daily, fluid therapy. Right now we have four or five cats in the practice who are nearing this timer period or are over it. On the other hand, we have cats who live less than a year. I suspect that most of our patients live between 1 and 3 years after the decision is made to go to frequent fluid therapy administered at home. There are a lot of additional therapeutic measures that help in controlling the progression of kidney failure in cats. Low protein/low phosphorous diets are very helpful. Calcitriol administration seems to help a lot of cats. Hypotensive agents such as amlodipine (Norvasc Rx) and enalapril (Enacard Rx) seem to be helpful. We have better luck with Norvasc but have had some success with both medications. Phosphate binders like Amphogel (tm) are also helpful, more so if calcitriol isn't used. Appetite stimulation is sometimes necessary. Fluid therapy is the mainstay of treatment but these other options can help, too. The longest a patient has lived after having severe elevations in renal values (creatinine >5, BUN > 150) was eight years. We used almost all of the above products in that particular patient, except the Amphogel. Hope this helps. There is a link to a good site on feline renal failure on our link page. Mike Richards, DVM 10/9/99

Kidney Failure

Q: Dear Dr. Richards, I am a subscriber to Vetinfo digest. My 17 year old cat, Tigger Alice, has been having progressively worsening kidney failure. I have a wonderful vet here in NYC, but I always get nervous when I go and don't ask all the questions I have. Tigger Alice is now on fluids that I inject every other day. I just started two days ago and today will be my second injection. My doctor wanted me to give her fluids once a day, but I bargained for every three days and we settled on every other because I really hate sticking her. I think it must hurt. But I would do anything to keep her healthy. We will be going to the vet in a month for a follow-up check up. Tigger also takes tapazole every day for her thyroid. My question is (finally!); should I have injected her every day? I don't know anything about this "creatinine level" thing other than what I've read at Vetinfo. My vet said her level is 3.5 and that normal is 2.5. With that 3.5 level, is every other day of fluids going to be ok or did I make a mistake? Does the constant puncturing hurt Tigger Alice? Is there any other method of getting the needed fluids into my cat? I actually didn't mind injecting her. I thought it would be horrible and I built it up to be so awful in my mind that it wasn't bad at all. It's just that I'm afraid of hurting my cat after many punctures in the future. But, if this is all there is, this is what I have to do. Also, any suggestions on how to get her to eat more? She's 7 pounds now and the vet would like her to be 8 and1/2. I leave out food all the time; both wet and dry. Thank you for your time. I think it's incredible that you do this service for people. I find the online information at Vetinfo so helpful, too. L

A: L There isn't a clear answer to your question. We have cats on all sorts of intervals of fluid therapy, ranging from people who give fluids at the first sign of problems, such as inappetance, but not routinely, to people who give fluids every day. In general, I think that people are pretty good at evaluating their cat's need for fluid therapy based on their assessment of their cat's attitude. If Tigger Alice seems to feel better on fluid days than on non-fluid days, I'd go to giving it everyday. If she doesn't show much difference in her attitude then the longer spacing is probably OK. It is unlikely that you would cause any long term harm by starting out with fluids at intervals of 48 hours and then deciding later they needed to be given daily. I am pretty sure that the needle punctures do hurt. I think that there are cats who appear to learn that the fluids make them feel better, though. We have had several clients who really felt that their cats would seek them out for fluid therapy when it was necessary. Of course, there is no way of being sure of that. In any case, sometimes it is necessary to cause some discomfort in order to get a greater level of overall comfort and quality of life. Thinking of it that way can make it easier when it does seem like you hurt Tigger Alice making the injection. You could try adding a little oil to her food. A teaspoonful of oil has a lot of calories in it and the higher fat doesn't seem to hurt the kidneys. I don't usually worry much about weight if the cat feels good but it is reassuring when they begin to gain weight back so I can understand the desire to see this. It is a big commitment to go to at home fluid therapy but it is usually worth the effort. Mike Richards, DVM 9/1/99


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...