Renal Failure in Dogs

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Stanozolol (Winstrol-V tm) and poor appetite with renal failure

Question: Dr. Richards,

Princess is a 16-year old Pom weighing in at 11 lbs. She is somewhere in the end stage of kidney failure.

Question 1: She is given a weekly injection of 25 mg. of winstrol. At what level is this dosage? And is one of the side effects heightened activity? Princess kept me awake for a goodly portion of last night when her constant rearranging of her blankets and pillows. What are some of the potentially serious side effects of this drug?

Question 2: Princess currently receives 250 ml. daily of LRS. Would upping the volume help to improve her appetite? Inappetance continues to be a major problem.

Tony

Answer: Tony-

The recommended dosage of stanozolol (Winstrol-V tm) for small dogs by injection is 25mg once a week. No dose range is suggested. For large dogs it is recommended that Winstrol-V be given at a dose rate of 50mg once a week by injection. It is available in an oral form, as well. When using the oral tablets the dose for small dogs is 1 to 2mg per dog per day and for large dogs it is 2 to 4mg per dog, per day. There is surprisingly little information on the effects and side effects of stanozolol in the veterinary literature considering that it has been around a long time. In cats there are reported cases of liver damage that appear to be related to use of the medication. In dogs the only side effects that are reported are "androgenic effects", which might include increased aggression, increased activity, weight gain and mood alterations. We do not use this medication in our practice so I do not have much personal familiarity with it.

Increasing the fluid dosage will only increase Princess' appetite if she is dehydrated or uremic (has toxins in the blood stream that should be removed by the kidneys but that is not happening). A poor appetite may very well be due to the presence of either of these conditions, though. If so, increasing the fluid dosage might help with the situation.

Mike Richards, DVM 2/27/2001

Tap water vs bottled water for Pom with renal failure

Question: Dr. Richards,

My 16-year old Pom has been diagnosed as being somewhere at the end stage of renal failure. The suggestion was made that she be given plenty of fresh distilled water to drink. I am wondering, however, if it would be a good idea to let her drink regular water once in awhile for the minerals that regular water contains. Question: How is "once in awhile" being defined here? Would it be defined as being once a week, every other day, every 3 fill-ups, what?

Sincerely, Tony A.

Answer: Tony-

The only reasons that I can think of to use distilled water over tap water for pets with kidney disease are to be sure that the taste is consistent, making them a little more likely to drink the water and to avoid using water that has been through a water softener, which adds salt to the water. It is better to have a low sodium intake when kidney failure is present so avoiding water from the water softener makes sense. The other minerals in the water are not necessary if you are feeding a well balanced diet. The commercial food manufacturers do not try to compensate for minerals in the water so all mineral needs should be met by the diet. If you are feeding a home-made diet there probably isn't enough impact from minerals in the water to worry too much about this issue, either.

If you know that your tap water is high in sodium, it would be best just to avoid giving it all together. If it does not contain a lot of sodium then there is no reason to worry about using it that I am aware of.

Mike Richards, DVM 2/17/2001

Renal failure - problems with appetite loss

Question: Dear. Dr. Richards,

Why is it that dogs with renal failure become very picky about what they eat? Princess will eat most foods only once or twice and then not even touch it again despite the fact she tells you she is hungry and wants/needs to eat. It's very exasperating when she tells you she is hungry, but when you offer her all kinds of foods she will just walk away. I feel that I am running out of options and that she will slowly starve herself to death.

Tony

Answer: Tony-

I have asked a couple of people who have kidney problems requiring dialysis what it feels like to have kidney failure. Both of them told me that they feel really good the day after dialysis, then gradually start to feel tired and/or sort of like they have a mild case of the flu over the next few days. My guess is that dogs with kidney failure have a similar experience with just not feeling completely well. Their appetites are probably decreased due to this and therefore food has to be a lot more attractive to be inviting, often making it very hard to find a diet they will consistently eat. I think there may be some association made between eating a food and feeling bad that day, too. I think this is one of the reasons that changing foods seems to help sometimes. Doing everything you can do reduce the effects of the kidney disease, such as fluid therapy, phosphorous restriction in the diet, calcitriol use (if possible), perhaps blood pressure or angiotensin-converting enzyme (ACE) inhibitor medications, gastrointestinal protectants like famotidine (Pepcid AC tm) and nursing care all can help to keep a dog feeling well and more interested in life and eating when they have kidney failure. It is a frustrating illness to be faced with. All you can do is provide the best chance for your dog to feel good by working with your vet and with your dog to compensate for the kidney failure.

Mike Richards, DVM 2/19/2001

Canine Renal Failure

Question: We are particularly interested in new research and/or treatments for canine renal failure (acute and chronic).

Answer: There is not a lot of brand new information on this subject but I thought it might help to review some of the current thinking on renal failure, just in case.

The most basic part of treatment for canine renal failure is fluid therapy. Aggressive fluid therapy early in renal failure (it is important to be certain the kidneys are at least producing some urine output before getting TOO aggressive) can make a big difference in prognosis. Even in chronic renal failure administration of fluids can be very helpful.

Angiotensin converting enzyme inhibitors (ACE inhibitors) are being used more frequently in renal failure patients to try to conserve protein in renal failure patients by limiting protein loss into the urine. Enalapril (Enacard Rx) is the most commonly mentioned ACE inhibitor for this effect. These also help to control high blood pressure, which can be a side effect of renal failure.

Calcitriol is being used more often in dogs to try to limit the problems with hyperparathyroidism that occur in conjunction with renal failure. This may help patients with renal failure feel better, at least.

Potassium administration seems to help some dogs. If you are using one of the formulated diets for renal failure, such as Hill's k/d diet or Purina's NF diet it may not be necessary to supplement additional potassium, though.

Phosphate binders help some dogs. These are over the counter medications, such as Amphogel (TM). For some reason, though, I remember seeing a note that Amphogel was hard to find lately.

If anemia is present with chronic renal failure it may be helpful to use erythropoietin injections or nandrolone to stimulate the bone marrow. The erythropoietin injections work better if there are not resistance problems with this medication.

Medications to protect the stomach and intestines from irritation due to renal failure can be very helpful, as well. Cimetidine (Tagamet Rx) and famotidine (Pepsid AC Rx) are two examples of these kinds of medications.

Hemodialysis is, or was at least, available at some sites in the United States, for dogs with chronic renal failure. Transplantation of kidneys, while somewhat common in cats, doesn't yet work as well in dogs and is not an option at this time, as far as I know. (maybe some research is going on with this that could be tapped into). If there were a dialysis center near me and I could afford it, I would definitely consider this option.

If you need more specific information on any of this, I will be glad to try to provide it.

Mike Richards, DVM 3/15/2000

Chronic and acute renal failure in dog

Question: Dear Dr.,

Our dog Teddy Bear died on tue. am in my arms from an apparent heart attack. perhaps I was too agressive with the fluid, I don't know if it was congestive heart failure or not. He was very very dehyrated by the time we began with the fluids on Fri.,first sub-q then IV on Sat.. He received approx. 3.5 to 4 L over the next three days and appeared to be voiding sufficiently. My Vet told me that he was doomed after he saw the blood work on Wed. morning of last week. he said that Teddy's kidney were now set on dehydration and that there would be no way to change that. I always thought that renal failure meant that you needed to be diuresed because of inability to void? And that is why dialysis was done so that removal of urea and other waste products could be achieved, owing tio the fact the kidneys were not filtering or were blocked. Is there a difference in symptoms between chronic and acute renal failure?

James

Answer: James-

It is very unlikely that you could have contributed to Teddy' Bears death by advocating the use of aggressive fluid therapy. In veterinary medicine, where dialysis is rarely available, the use of large volume fluid therapy is the most successful treatment for kidney failure, whether it is acute or chronic. Peritoneal dialysis is sometimes helpful in acute renal failure in situations in which the kidneys can be expected to survive the current insult and recover some function. It is difficult to use peritoneal dialysis as a therapy for chronic renal failure, though. There is a small chance that fluid therapy could have been too much for a weakened heart but if so, it was still not wrong to try it, since it was the only viable choice for long term treatment success. The fact that fluid therapy did not help is just an indicator that the problem was too severe or too complicated to respond, not an indication of a bad treatment choice.

There is no really clear difference between acute and chronic renal failure, except that acute kidney failure is the name that is usually applied to sudden catastrophic kidney disease caused by an infection such as leptospirosis, a toxic insult to the liver from anti-freeze or mushroom poisoning, blood clots that damage the kidneys or similar sudden insults. The treatment plan is actually the same except that in acute renal failure early recognition and early high dose fluid therapy may be the only hope for saving the kidneys. High dose therapy usually involves fluid therapy at rates of about 50 to 150mg/kg/day, or 0.5 to 1.5 liter per 22 pounds of body weight, per day.

Chronic renal failure is usually used to describe acute renal failure once the patient has reached the point where there is residual kidney damage still causing problems but it seems evident the patient will live or in situations in which the kidney failure occurs very slowly over a long time until it reaches the point it is evident and that it must be managed. Chronic renal failure is also usually treated with fluid therapy when blood values indicate the necessity for that therapy but is also managed using dietary changes, phosphorous control, treatment for any primary problems and control of secondary problems like high blood pressure and gastrointestinal irritation.

I have not been able to figure out how to tell which pets will respond to fluid therapy and which will not, in advance of trying it. If we get no response to the administration of fluids (no improvement in lab values or patient attitude) within 48 hours, I start to think it won't work. If there is a good response in either lab values or patient attitude I am usually in favor of keeping going with therapy until there is no more improvement. At that point, we try to assess whether the current level of kidney function is enough to support a reasonable lifestyle. So I would have wanted to try therapy, just as you did, even though it didn't work for Teddy Bear.

Most pets with acute or chronic kidney failure are still producing urine. They just can not adequately filter toxins from the blood stream by producing concentrated urine. Diuresis just causes more urine to be produced, washing more toxins out of the bloodstream without having to have concentration of the urine. Pets that are not able to produce urine require therapy to get them to produce urine prior to diuresis.

Shar peis are prone to amyloidosis, which leads to chronic renal failure. I am not sure that this is what happened with Teddy Bear, but it may have been. I do not know of any treatment that will prevent the occurrence of this problem.

If you need more information about any of these topics please let me know.

Mike Richards, DVM 9/1/200

Renal Dysplasia Test in Lhasa Apsos

Question: Dr Richards, Thank you for your prompt reply. One other question has come up. If Lhasa Apsos had a DNA test for Renal Dysplasia, would that test be able to be used on another breed? In other words, can tests cross breed lines? One more thing. At what age of puppies can you test for congenital kidney problems and what test can be used, besides urine. My vets told me that the only sure test is an invasive kidney biopsy at at least 6 months. Thank you, again, Carol Carol-

There is a genetic test for renal dysplasia in Lhaso Apsos, shih tzus and soft coated Wheaton terriers, which is specific to these breeds, as far as I know. You can find information on this at:

http://www.VetGen.com/renaldys.html

It is possible to contact the company from this site and they may be able to tell you more about genetic testing for this disorder.

It is possible to begin testing for signs of kidney disorders as soon as clinical signs of the problem are clear. There is some problem in interpreting kidney related blood values in young puppies, though. BUN, phosphorous and creatinine can be elevated in a puppy compared to an adult and puppies may not achieve adult levels of urine concentrating ability until they are four or more months of age. So a puppy that seems as if it might have a problem, may not. When considering a test that has some risk associated with it, such as a kidney biopsy, it is usually better to be certain that testing is necessary. If it is apparent that there is definitely a problem prior to six months of age, a biopsy can be done earlier than six months. Sometimes X-rays and ultrasound examination can give an idea about kidney size and structure that make it possible to be more suspicious that kidney problems are present. X-rays using dyes can help to determine if flow through the kidneys is normal, another test that can help to determine what might be wrong.

It is possible to tell that kidney disease is a problem without kidney biopsy but it is often impossible to confirm the type of kidney disease without kidney biopsy. Since you are involved in a breeding program, knowing exactly what problem is present is more important.

I hope this is helpful.

Mike Richards, DVM 8/24/2000

Renal Dysplasia, Renal Hypoplasia and polycystic kidneys

Question: Dr. Richards, I have questions regarding Renal Dysplasia, Renal Hypoplasia and polycystic kidneys. Do you know if it is carried by a single carrier or does it take two? Also, are there degrees of Renal problems? I have had several dogs that have been diagnosed with Renal Dysplasia and, tho they are related, there seems to be skipping of generations. One of my first bitches was never diagnosed, but had kidney problems as she got older, was on Kd for years, then fluid therapy and final was euthanized at 11 1/2 years of age. She did drink alot of water when young and her urine was dilute. But, I wonder, if she had been born with renal dysplasia how she could have lived that long. She was a finished champion and had been bred several times. She, also, had eclampsia twice which I know can affect the parathyroid glands which can affect the kidneys. She never produced any puppies or dogs with renal dysplasia, but several of her offspring did - 6 in all of 4 generations, which includes 90 puppies (dogs). i would appreciate any information that you can give to me, as I have an ongoing showing/breeding program and want to be a responsible breeder. Carol

Answer: Carol-

In West Highland white terriers, polycystic kidney disease is thought to be an autosomal recessive disorder, so both parents have to be carriers in order for the disease to occur. (McAloose, et al, Vet Pathology, Jan 1998). In bull terriers, one report suggests the problem is an autosomal dominant trait, which would require only one parent to carry the gene (Burrows, et al, Journal of Small Animal Practice, 1994). So I am guessing that this disorder varies from breed to breed. I couldn't find any specific information relating to bichons.

Renal dysplasia is thought to be a simple recessive problem in shih tzus ( Bruyette, Veterinary Information Network (www.vin.com), 1996) but I couldn't find specific information on mode of inheritance in bichons for this condition, either. There is a second post on the Veterinary Information Network which says that this condition is recessive but requires two separate recessive genes to be expressed --- which would explain the difficulty tracking it that you are experiencing. This is explained some at this web site: http://www.vet.upenn.edu/comm/publications/bellwether/40/articles.html

I agree that it would be really unusual for a dog born with renal dysplasia to make it to eleven years of age. Once in a while this sort of thing happens, though. Still, I think you can safely assume that wasn't the case.

I hope this helps some. If I run across more specific information I will try to remember to send it or post it on the site.

Mike Richards, DVM 8/18/200

ACE inhibitors and CRF in dogs

Question: Hi again, Dr. Richards!

I passed your info, re the ACE inhibitor, on to our vet, and she had to admit that she knew little about this treatment and had been unable to find material on the subject. She is willing to try this with Trudi but needs to find info as to dosage, etc. Can you help us out here?

Although I would consider her well-read on continuing ed, she also says that she is not familiar with high amylase readings in regards to CRF. And it DOES certainly seem that Trudi's all-too-frequent bouts with pancreatitis must be due to her CRF......as her diet is surely VERY strictly controlled. This week, for 3+ days, she was on nothing but home-cooked chicken broth, defatted, and with NO salt. Tonight, I finally added abit of Cream of Rice cereal & a few spoonsful of her homecooked diet. For the most part, she drinks adequate water, though earlier this week I did take her in for 300 cc's of Lactated Ringers, sub-q,as she was looking dehydrated.

As always, we greatly appreciate ANY input you can give, re Trudi's situation! TIA

Greatfully, Rozanne

Answer: Rozanne-

There is a pretty good explanation of the benefits of ACE inhibitors in Kirk's Current Veterinary Therapy XIII, page 852. Your vet might have access to this reference, although this is the latest volume and is pretty new. The recommended dosage for enalapril (Enacard Rx) is 0.25 to 0.5mg/kg once or twice a day). This medication is used in humans to help prevent protein loss in the kidneys but it also helps in lowering blood pressure. It is better if it is possible to monitor blood pressure but many veterinary clinics are not yet equipped to do that. It is important to note that enalapril is not approved for this purpose and that the published research on enalapril in kidney disease in dogs is limited to a couple of papers, including one that was done exclusively in samoyed dogs due to an inherited glomerulonephritis in that breed.

Amylase is elevated in kidney disease because the kidneys remove it from the circulation and if they aren't functioning well they don't remove it as well, causing the levels to rise. In addition, dehydration is common in patients with kidney disease, which also causes some elevation in amylase values. The values do not get as high as they usually do with pancreatitis but they can definitely get well beyond the normal range. A very good reference that has extensive lists of causes for abnormal lab values is "Small Animal Clinical Diagnosis by Laboratory Methods" by Willard, et. al. This reference has helped me avoid overlooking potential causes of elevations or decreases in lab values on a number of occasions. Some references note a link between renal failure and pancreatitis but I don't think that has anything to do with elevations in serum amylase due to decreased kidney function. I think something else contributes, if this link does exist.

In looking for this documentation of the effects of enalapril, I noticed a plug for low dose aspirin therapy in patients with kidney disease in the same article in Kirk's. This might be something else to think about doing.

It can be helpful to monitor for acidosis in dogs that are having a bout of not feeling well associated with chronic renal disease, as this is a common problem in renal failure patients. There are medications, such as potassium citrate, which can help to increase the pH of the blood, if necessary.

Hope this helps some.

Mike Richards, DVM 6/18/2000

CRF

Question: Dear Dr. Richards. apologies for the wrong cc no.only excuse is my 18 year old bunky was diag.with crf and in my hurry to get on line with you i messed up txs for your kind offer to e mail you before subscription approved.my question is:bunkys just diagnosed blood and urine panels are very high;creatinine 465 urea 357 in spite of this his demeaner is good and he is still eating and drinking well urination is high.at this point my vet has not discussed Sub Qs or any drug therapy and i would like to know if any of these procedures would help at this time.also wud it be appropriate to approach my vet re these matters seeing as how he chose not to broach these matters other than discussing dietry changes and to inform me that the outlook was not good.any advise at this time wud be greatly apprec many txs Don.

Answer: Don-

Unless I missed it, you didn't say whether Bunky was a dog or a cat.

The answer if Bunky is a dog is this: you need to talk to your vet about intravenous fluid therapy, especially if there is evidence of ongoing deterioration in Bunky's condition. Early aggressive treatment of renal failure in dogs is really pretty essential if they are going to have much of a chance with renal failure and they do not do as well as cats, even with aggressive care. Dogs seem to be helped by administration of enalapril (Enacard Rx, Vasotec Rx) based on the last three or four cases of renal disease in our practice.

If Bunky is a cat, there are many possible avenues for treatment and the prognosis is much better for long term control of the renal insufficiency. We usually use subcutaneous fluid therapy for the first few days, until the cat feels better and will eat well. In some cases it is necessary to start fluid therapy on a regular basis almost from the start of signs and in other cases, intermittent use when the cat doesn't feel well is sufficient. In a few cats, we catch the renal problems through lab work or some other way when there isn't inappetance or dehydration and in these cats we sometimes do just dietary management at first.

Many cats with renal failure have low potassium levels and most cats seem to feel better if potassium is supplemented. We are going to blood pressure control medications earlier now than we have in the past, as amlodipine (Norvasc Rx) really seems to make some of our patients feel a lot better. We use calcitriol frequently, as it also seems to make cats with renal failure feel better. When necessary, we use appetite stimulants, phosphate binders, gastrointestinal protectants such as famotidine (Pepcid AC Rx) and medications for secondary problems, like infections or anemia.

There really is a lot that can be done to make cats with renal insufficiency feel better and live longer. Let your vet know that you are really interested in providing the best possible care for Bunky.

If you need more information on any aspect of this treatment, please let me know.

Mike Richards, DVM 4/22/2000

CRF and vaccination schedule

Q: Hi Dr. Richards!

One quick question re Trudi & her CRF. Her annual inoculations are due within the coming few weeks. She normally gets:

Lyme booster Smith Kline rabies 1 yr booster DHLPP adult booster Bordatella 1 yr booster nasal spray

In your considered opinion, are all of these still safely indicated with Trudi.....given her CRF? Number-wise, her blood work is pretty stable, with only the phosphorus varying by .01, or at most .02 each month. She looks good, is maintaining both appetite and weight. Naturally, she tires easily but paces herself well. We continue to do our Delta "Pet Partner" hospital and nursing home visits, which she loves; she also participates, weekly, in advanced obedience and agility classes.

TIA for any opinions you'd care to share, re the inoculation-schedule!

Regards, Rozanne

A: Rozanne-

In patients at our hospital with CRF we judge the necessity for vaccinations on two issues.

If the cat or dog has a history of vaccine reactions, even just feeling "low" after a vaccination, we tend to avoid it, if possible. Rabies is required by law, so that one isn't usually avoidable. We think that this is a reasonable choice in most patients, unless there is some reason to suspect they are going to have high exposure to one of the diseases vaccines can protect against (such as dogs and cats that go to shows).

The second thing we think about is the stability of the response to treatment for the renal disease. If the dog or cat seems to be at a stable point we are a lot more likely to consider the vaccinations to be worth the small risk they pose. If the pet is losing weight, not having good control of BUN, creatinine, phosphorous or other lab values we monitor for kidney failure, then we are less likely to want to place any additional burden on their system. Of course, we are also usually advising not to put these pets into a situation in which they will be exposed to infectious diseases, if at all possible.

So it isn't an easy choice but I am very willing to wait on the distemper/parvo combinations, usually give rabies on schedule and really try to assess the risk of tick exposure and exposure to dogs that might have kennel cough (tracheobronchitis) before administering either Lyme or bordetella vaccinations.

Mike Richards, DVM 8/22/99

Calcitriol for treatment of CRF in Boxer

Q: Hi again, Dr. Mike! We're not entirely comfortable with our two vets' ideas, regarding Boxer "Trudi" and her CRF, due to the malformed medullas of her kidneys. Reason: they seem to be grabbing at straws.

We started calcitriol (.05 ml daily) approx. 8 weeks ago. Since then, Trudi's fasting blood workups have not shown any improvement. Her phosphorus levels, for instance, remain too high. We see the 2 vets on a somewhat-alternating schedule, and neither of them seems to be totally agreeing with the other. One just continues to order total blood chem panels (with phosphorus) every 2 weeks. She has just chg'd Trudi's calcium suppl. from 2500 mg. (daily) of Tums to 1800 mg. of Amphojel. This same vet mentions checking parathyroid levels but then doesn't follow through.

I often feel like we're just "pawns" in all of this. I can understand only to a point. Although we dearly love our dogs, and would do anything to help Trudi, we are now beginning to feel that these are just "fruitless stabs in the dark".

As a vet, what would you recommend, at this point in time?

Best regards & TIA, Rozanne

A: Rozanne-

I think that I have not explained the use of calcitriol as well as I should have on this site. I am hoping that the following information will help clarify this issue.

1) The phosphorous level should be controlled prior to the use of calcitriol, if at all possible. I have been somewhat confused by this issue, myself. The problem is that calcitriol doesn't have as much effect on phosphorous as it does on calcium levels and parathyroid hormone levels. Control of phosphorous is best done using low phosphorous diets and phosphate binders such as Amphogel and Basalgel. If the phosphorous level is above 6 mg/dl is best prior to starting calcitriol. I don't think there is any harm in using calcitriol when serum phosphorous levels are above 6 mg/dl but it may not be helpful in this situation.

2) There are veterinarians and veterinary specialists who feel that phosphorous restriction (through diet and phosphate binders) alone is sufficient in renal failure. This may be true. The proponents of calcitriol seem very convinced that it makes patients with kidney failure feel better and live longer, though.

3) Calcitriol does have a more significant effect on ionized calcium and total calcium, usually causing both to rise. It also should cause a decrease in parathyroid hormone levels because they rise in response to low calcium.

4)To make this all even more confusing, in renal failure the total calcium level will often rise due to metabolic changes. However, the portion of the calcium in the blood stream that is free for the body to use (the ionized calcium) will stay normal or low. This means that there are times when it appears that it would not be a good idea to use calcitriol (when calcium is higher than normal) when in fact it would be beneficial (because the ionized calcium is low). Unfortunately, many vets do not have a reasonable way of measuring ionized calcium in their practices.

5) Measuring the phosphorous level every couple of weeks is reasonable when trying to get it to drop and stay at a level less than 6 mg/dl. Monitoring phosphorous and calcium is reasonable as often as monthly when using calcitriol but this depends on financial resources. If money is limited, monitoring less often is probably OK. Monitoring parathyroid hormone levels is also useful (they should drop if the calcitriol is working for the patient). However, this is also an additional expense and again the financial impact has to be considered. In practices that use some in-house blood analyzers it may be necessary for the practice to run a whole panel to get one result. This is a drawback of some machines. I don't see a reason not to use an outside lab and request just the lab values necessary, though. In this case, instant turn-around on lab results isn't really essential.

5) Calcitriol is not going to make renal failure go away. If it does all that it is supposed to do it will make the patient feel better and live longer. These are significant benefits but they are subjective things and you have to remember that they are comparisons to pets with renal failure not getting calcitriol --- not comparisons to normal dogs! Feeling better is a relative thing.

I am sorry if this topic has been confusing on our site -- especially if it still is.

Mike Richards, DVM 7/11/99

Chronic renal failure in Boxer - calcitriol may help.

Q: Hi, Dr. Richards! Abit of HA before posing my questions about Trudi, our just-past-3-yr-old sp. F boxer. A fairly prolific "leaker" since our adopting her from her show/breeding home @ the age of 13 mos. Spayed @ the age of 13.5 mos......quick, uneventful recovery. Blood chem panel drawn Aug. of '98, showed slightly elevated BUN, creatinine, SGOT, SGPT. U/A unremarkable. Testing repeated in mid Sept.......values not much different. I still insisted that, after 45+ yrs. with boxers, Trudi "wasn't right". In Jan. '99, she virtually quite eating/drinking, and our great vet missed the diagnosis again........did diuresis for 3 days, followed by I/M "pushes" with lact. ringers. Local ultrasound & xray of kidneys still produced no diagnosis, so we were referred to the vet teaching facility at OK St. U. Ultrasound & xray there showed congenitally malformed medullas.......resulting in chronic renal failure. Their long-term prognosis was bleak, but Trudi was immediately begun on a combo of canned k/d (she dislikes the kibble intensely!) and home cooked low phosphorus/protein diet. She perked up then & there.......and continues to *look* great. She is on a regime of 00 mg. cimetidine 3 X daily, and her only sign of abnormality is an "acid-y" odor to her breath. Monthly blood work ups are done, and both the March and April reports were actually pretty good.......with the albumin lightly skewed. Her U/A, done on Sat., 4/17, was terrible.........sp. grav. of only 1.013, down from a mid-Feb. reading of 1.8. Obviously, her kidneys are *not* functioning well at all. Now, my questions: we are fully aware that Trudi probably doesn't have much quality time left with us. Will there be signs other than her outright refusal to eat and/or drink? Will she gradually lose pep and energy, or is the end more likely to be fairly quick........leaving her with good quality of life right up to the end? Will she be in pain? Both of our boxer girls are registered Delta "Pet Partners" and do approximately 22- 26 hrs. of visitations each month. Trudi loves to go.......but are outside activities too strenuous for her, given her fragile state of health? Would you recommend that she not attend the intermediate obedience classes which both she and I enjoy? We've never lost a young boxer........and are in a quandary as to what we should be looking for, as well as the best way to treat this precious "babe" of ours during her last months. Any light you could shed on this subject would be greatly appreciated. TIA Sincerely, Rozanne & Jack

A: Jack and Rozanne-

I am not sure that I can offer much help with Trudi, but it may be helpful to consider the use of calcitriol. A lot of the work on the use of calcitriol has been done by Dr. Nagode at Ohio State University and he was one of the authors of an article in the Veterinary Clinics of North America on the use of calcitriol (Nov, 1996). He believes that it slows the progression of renal disease in most patients.

Urine specific gravity testing is best interpreted based on the results from several urine samples over the course of the day or over the course of several days. Urine concentration varies widely even in pets with completely normal kidneys. The most concentrated urine typically occurs before a pet urinates in the morning since it has been held in the bladder overnight. As the day goes on and urination occurs more frequently, it is not unusual for a pet with normal kidneys to have a dilute urine sample. I wouldn't get too depressed by one unconcentrated urine sample. It would be a bad prognostic sign if Trudi does not have a urine concentration greater than 1.025 to 1.030 at some time during the day, based on several urine samples, though.

Normally, pets with kidney failure gradually lose weight, usually drink much more than normal and usually urinate larger volumes or more frequently than pets not affected by renal failure.

We have some information in past issues of the VetInfo Digest on interpreting lab values related to kidney function.

I will try to review this information again and check into this condition as it specifically relates to boxers. If I find anything, I'll send a follow-up email.

Mike Richards, DVM 4/21/99

Fluid therapy, monitoring renal failure

Q: Little Red's BUN had dropped to 75 but now is back up to 140 - We restarted the Subcutaneous saline. Is there anything else we can do ?

In the last week he has been much better. He almost has his trot back and is alert and active. He gained weight up to 9 lb. 4 oz. We were surprised and disappointed by his BUN test.

Testing Urine: If we do this - so what ? Will it give us information to do something we are not doing ?

The problem is now his mouth and tongue - he has lost 1/3 of his tongue due to decay and has sores. It's hard to eat.

Subcutaneous saline is used to diurese dogs with renal failure. Dialysis is not commonly used in pets due to the expense and lack of treatment facilities. Diuresis offers a lower tech alternative. Fluids are administered to force the kidneys to remove them and to drag some of the accumulated toxins out with them. As long as it is not overdone (this rarely happens) the more fluids that are administered, the better.

We are now using subcutaneous saline twice a day for several days to diurese dogs with renal failure, there is a marked improvement.

A: Dr. P

Subcutaneous fluids are an effective way to aid the kidneys when renal failure is causing inadequate excretion of waste products. I prefer to use a buffered fluid such as Normosol or lactated ringer's solution over saline. It may be necessary for us to check the site and correct this statement if I have stated that saline is better somewhere.

It is worth monitoring something to evaluate whether or not the kidneys are responding to this therapy. In some pets it is easiest to monitor the urine and in other pets it is easier to monitor the blood values for things like BUN, creatinine, potassium and phosphorous levels. Monitoring urine protein levels, urine/creatinine ratio and specific gravity of the urine can all help in evaluating how the kidneys are doing. Sometimes we reach a point where we realize that a dog or cat is simply going to require daily fluid therapy in order to maintain adequate kidney function. Once we reach this point then monitoring becomes less important as a means of determining when to consider treatment. It still provides prognostic information, though.

Dietary control of protein and phosphorous levels using diets like Purina's NF and Hill's k/d can be helpful. Phosphorous binding agents can be useful if phosphorous levels are rising. Potassium supplementation seems to help delay the progression of renal failure, especially when the values are lower than normal without supplementation. Some dogs will need to have gastrointestinal protectants such as cimetidine (Tagamet Rx) and others need appetite stimulants at times, although these work better in cats than they do in dogs. Control of high blood pressure is helpful if it is present.

It is really important to have a good working relationship with your vet in order to have the best shot at good long term control of kidney disease in dogs or cats. Keep talking to your vet and keep working with your vet. If it becomes financially difficult to do everything your vet would like to do then tell your vet and try to work out a plan that will provide the maximum benefit for the amount you can spend.

Most dogs can adjust to the loss of a third of their tongue. It may take a little more time but I really do think that he will adjust to this loss.

One thing that you have to remember is that everyone who is giving you advice who can not evaluate your dog in person is missing part of the picture. There may come a time when you know that the fight is not worth it or when your vet tries to tell you that there is not much hope for stabilizing this condition anymore. Please trust your instincts when this happens. In the end you know Little Red better than anyone else. I am not sure if I am typical of veterinarians but sometimes I don't know when to give up, especially when I am dealing with conditions that appear to have a traumatic origin, which always makes me think that the body will be able to repair itself if I can just help the pet fight long enough.

I will continue to hope for the best for Little Red.

Mike Richards, DVM

Chronic renal failure

Q: Dear Dr. Mike, My mother owns a sixteen year old cocka-poo who was diagnosed with chronic renal failure about two months ago. My mother tried to stick to the renal diet prescribed for the dog (Missy) but she would have none of it. Watching her waste away was hard, so for the past few weeks my mother has let her eat whatever she will. She seems to especially like milk shakes. As time has gone on, we notice that she has experienced terrific weight loss, muscle shakes, extreme weakness and loss of balance, at times. My mother did not want to dialyze her; just keep her as comfortable as possible until her time comes. Her vet prescribed saline SubQ which we have been using - my mother does not know why it >was presribed (dehydration?) Here are my basic questions:

#1 - Are her symptoms all normal for chronic renal failure? What causes the shakes? (Low calcium?) Can we do anything to prevent the shakes? Is she in any pain with renal failure?

#2 - What can we expect in the future - i.e. what will be her most likely terminal event?

#3 - At some point we may decide to "put her down". This is a very hard decision and we don't want to do it too soon. What guidelines can we use to decide when the time has come?

#4 - Any suggestions to keep her peppy for the summer? My mother would like her to survive through this one last summer if possible.

#5 - Any other references you would recommend I could check out on the subject?

Thank you very much for any advice you can offer; my mother is really suffering along with this much loved pet. Daughter of Mother with Pet, Janis

A: Janis- Renal failure is harder to manage in dogs than it is in cats (or at least it is harder to manage with success). Your mother's cocka-poo has probably done well to make it this far but it may be possible or her to keep going longer. Some dogs do respond well to therapy and nursing care. In answer to your questions, as best I can: Subcutaneous fluids are an effective way to aid the kidneys when renal failure is causing inadequate excretion of waste products. I prefer to use a buffered fluid such as Normosol or lactated ringer's solution over saline. Dialysis is not commonly used in pets due to the expense and lack of treatment facilities. Diuresis offers a lower tech alternative. Fluids are adminstered to force the kidneys to remove them and to drag some of the accumulated toxins out with them. As long as it is not overdone (this rarely happens) the more fluids that are administered, the better.

1) The most common clinical signs associated with renal failure are weight loss, increased drinking and increased urination. These occur early before much damage is done and are pretty consistent signs. The subsequent signs can be almost anything since renal failure has so many side effects involving other organ systems that almost any symptom can occur. Shaking may be directly related to drops in potassium levels in the serum since the kidneys do not preserve it well when renal failure is present or they can be the result of hyperphosphatemia and secondary renal hyperparathyroidism. In addition, hypertension is common in renal failure and it can lead to tremors and neurologic damage is not unusual in renal failure patients, either. Hypothermia can occur with chronic renal failure and it might produce shaking behaviors (shivering) too. Labwork to check phosphorous and potassium levels should be done, probably.

2) Most of the patients I have treated for chronic renal failure have been euthanized prior to a terminal event because they stop eating at some point and most owners give up after a few days of inappetance. I have seen bleeding disorders such as DIC force people into making the decision to euthanize in chronic renal failure and have had several clients wait until their pet was comatose before giving up.

3) I think that is covered above. It is a tough choice but when BUN and creatinine levels fail to respond to diuresis and total inappetance sets in most people elect to euthanize rather than to let a pet suffer.

4) I think it is very important to treat as many of the side effects as can be treated, as aggressively as possible, in order to prolong life and to make the lifetime remaining as comfortable as possible. Using medications such as cimetidine (Tagamet Rx) to ease nausea from gastric irritation, blood pressure medications if necessary, potassium supplementation, phosphate binders, subcutaneous or intravenous fluid diuresis and whatever else seems necessary can all help. I know it sounds like a lot to do but each medication has a specific purpose in the process. Feed her what she wants to eat if she won't eat the renal diets. Try to find low phosphorous, low salt items that she likes, if possible. Avoiding high protein foods helps in this situation. It is better that she eat than that she eat what she "should". If she gets stablized at some point, work harder to get her to eat the renal diets.

5) There was a recent "Clinics of North America" on renal disease. If your vet or your mother's vet subscribes to this journal it would be worth taking a little time to read it for further discussion of this whole issue.

Renal Failure in Dogs

Q: Dear Dr. Mike: I have been looking for some help with my dog ChiChi. If you could offer any advice it would be very much appreciated. My vet seems resigned to letting Cheech go...anyway here's the situation.

At least 12-year-old llasa/poodle/anyone's guess mix: diagnosed with renal failure (BUN up to about 120, after 2 days on iv down to 39) but she eats, drinks, acts "normal". Teeth are very bad and I want to get them cleaned and/or removed. Two vets say wait, even for iso-something gas which is supposed to be easier to take than standard anesthesia. But vets also said bad teeth cause/contribute to kidney problem. Any opinions? Should I get a 3rd vet to do teeth? Any home-cooked diet for renal failure?

Update... ChiChi's BUN is up to 55. Drinking a little less. Vet's strategy is to just wait until she's real sick, then bring her in for extended stay on iv. Won't show me how to do sub-q's. Keeps telling me to wait. Supposedly this vet clinic has rep for practicing medicine for the animals' sake, not profit's sake. However I feel like she's trying to max my bill out. Any thoughts or advice...Please?

Thanks very much for any advice. Ann

A: Ann-

There seems to be a tendency among veterinarians to treat renal failure in dogs less aggressively than in cats. This is probably because successful treatment seems to occur less frequently and it is hard to recommend therapy that requires a big commitment on the part of the owner for potentially small rewards. Recently there has been a lot more emphasis in the literature on aggressive treatment of renal disease in dogs, in particular the utilization of calcitriol, phosphate binders and blood-pressure medications.

In general I tend to think that it is better to clean the teeth in these cases than to let them go, but that is a personal opinion not based on scientific data. I can not remember an anesthetic death from attempting anesthesia in the face of renal failure in our clinic and I really believe the dogs feel much better after teeth cleaning.

If your vet is unwilling to be aggressive it would be worthwhile to ask for referral to an internal medicine specialist. This lets your vet know you are serious about treatment which can be motivating and it gives your vet a graceful out if she is just nervous about recommending aggressive therapy when it may not work. You have the right to chose that course for your pet and I do think that there is more success in the treatment of chronic renal failure in dogs now than in the past when a rigorous effort is made to treat them.

Mike Richards, DVM

Early renal failure

Q: I have an extremely active, very healthy, 1 1/2-year-old, 90 pound labrador who tends to leak urine when he sleeps. My vetrinarian's first thought was that it was an infection, but a urinalysis came back negative for infection. It did, however, show a "specific gravity" of 1.015, which is apparently below normal. The dog's PH level is also low, at 6.0 and a few calcium oxalate crystals were found. All of this means very little to me. My vet wants to run a full blood screening and seems to be concerned about kidney failure. Again, my dog is only 1 1/2 years old, and he shows no signs of ill health whatsoever. He does tend to drink quite a lot of water, I guess, and he urinates frequently, but this is hardly a new developmet. As I said, he is a very active dog and he tends to drink the most after a lot of activity and urinate the most after drinking a lot. I do the same thing. Two other things weigh in to my tendency to have reservations about performing expensive tests for rare disorders.

First, the symptoms seem to have worsened slightly since we got another dog, which means that he tends to be more tired and thirsty at the end of the day, and he only seems to leak when he is sleeping very soundly. The other is the fact that the dog never learned to let me know when he has to go. He will hold it all day, but he never scratches at the door or does anything to signal that he needs to go outside. This leads me to wonder if perhaps he is leaking simply because his bladder is full. He never has any accidents in the house, except when he is in a sound sleep, and even then it's never more than a slight drip. Could this problem simply be brought on by physical exhaustion? Is kidney failure a legitimate concern in a dog so young? I realize I've asked a lot here, and I apologize, but I really am very concerned about my dog. I would appreciate any guidance you could give. Tom

A: Tom- Labrador retrievers seem to be prone to developing kidney failure at an early age, based solely on the clinical experience we have had at our practice. While it is not common, Labs seem to be the most prone of all the breeds in our practice to developing early renal failure. They also seem to be prone to leptospirosis infection which can lead to kidney failure. Urinating more and drinking more are symptoms of this disease.

Urine specific gravity is a way to measure how well the kidneys are working. Normal kidneys can filter out solids well enough to make the specific gravity of the urine greater greater than 1.020 when it is necessary. Taking the first urine sample your dog produces in the morning (or the first time he goes out after being in all day) is a good way to get a sample of the most concentrated urine your dog can produce. Because the amount of concentration is variable, depending on the need to concentrate the urine and response to hormonal influences over the course of the day, taking one urine sample and trying to interpret it is not really reliable. It is better to take several samples over the course of the day and see if urine concentration occurs at any time. Urine pH doesn't have much bearing on the diagnosis of kidney failure but lower pH values make it less likely that cystitis is present. A few crystals are not all that unusual in urine.

Other than expense, I see no reason not to check blood values. It is nice to have lab values from a dog to compare to later in life, so even if they come out normal it isn't a total waste. I definitely wouldn't rule out taking this step.

It is always hard to decide what to do when the clinical signs are mild but a serious disease is possible. Unless money is really tight it would be best to be cautious, probably. In that case, rechecking the urine specific gravity at a time when the urine should be concentrated would be a good idea, at least.

Mike Richards, DVM

Congenital renal failure syndromes

Q: I am trying to get some information on Juvenile Renal Failure mostly as it applies to Miniature Schnauzers. What are the hereditary factors? I am assuming that it is hereditary. Thanks C-

A: There is a familial renal disease of miniature schnauzers, which is presumed to be heritable based on the pattern (related dogs being affected). I do not think the mode of inheritance has been established, nor is it certain that this condition actually is inherited. Despite this, it is probably not a good idea to breed a relative of a dog with this problem.

In most congenital renal failure syndromes the clinical symptoms of congenital renal disease do not usually appear before 4 months of age and may show up later in life, perhaps as late as two or three years of age. Typical signs of renal disease, including vomiting, weight loss, dehydration, increased drinking and urination occur. Anemia occurs as the disease progresses. While it is possible to slow the clinical course of these diseases with treatment it is eventually fatal. I am not sure if this is all true for schnauzers with congenital renal disease since I really only found a reference to the existence of the problem as a familial trait in Dr. Morgan's text " Handbook of Small Animal Practice".

Mike Richards, DVM

Renal Failure and Diet

Q: Dear Doctor, We have a three year old female golden retriever who was diagnosed 1 week ago with probable JRD. She was critically ill at the time. We were given a list of instructions for care including maintaining a low-protein diet. Because she had no appetite we have been preparing her meals. We have learned quite a bit about the benefits of a low-protein diet high in amino acids. Our problem is we have not been able to find out what the daily allowance of protein in grams should be. We are feeding her small meals 4 times a day, this appears to be working well and she has not had a vomiting episode in 4 days. She weighed 36 pounds at the of her diagnosis, she weighs 40 today. Before her illness she weighed 54. Could you please give us some guidelines for daily protein allowance? Everything we've researched points towards this type of diet being very helpful. We know that if we can get her through this crisis we can use a prescription diet but for the immediate future we feel she needs home prepared food. We know Bretts prognosis in not good but we are going to try to do everything we can for her. Thank you for any information you can provide.

A: I think that the current thinking on low protein diets is that the protein level is not as important as the phosphorous level. In trying to evaluate these diets several researchers have come to the conclusion that they work primarily because low protein diets tend to be coincidentally low in phosphorous. There is no clear connection between the low protein levels in food and progression of renal disease in recent studies. This really doesn't matter from a practical standpoint, since the best way to keep the phosphorous in the diet low is to keep the protein level low. Phosphorous levels should be kept as low as possible, about 0.3% of the diet (basically, this is as low as is practical - it is very very hard to get the phosphorous level lower than this).

It is desirable to try to keep the protein level at 14 to 19% of the diet (this is an average based on the recommendations I could find for renal failure diets). For a dog that weighs 44 lbs, approximately 1350 calories are necessary for maintenance per day. This is usually supplied by about 4 cups of dry dog food, which should weigh between 350 and 400 grams. I can not find a recommendation for protein in grams/day/lb. but using the above recommendations, it would appear that 400 grams of dry dog food at 15% protein would provide 60 grams of protein. I am assuming that would be the approximate amount necessary.

In general, renal failure in dogs does have a poor prognosis. We have seen several cases of early onset renal failure in recent years in which the dogs did do quite well on controlled diets and aggressive fluid therapy. I don't know if we have just been lucky but I do think giving this a really good try is worthwhile. I wish you the best of luck.

Mike Richards, DVM

Last edited 03/18/07

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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...

 

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