Articles-Kidney

Kidney

Information Articles -Kidney

Inherited Kidney Disease (IKD) has been reported in many breeds of dogs including the Bull Terrier and Miniature Bull Terrier as well as in people.
There are many different types of kidney disease, inherited (or genetic) faults being only one cause. Infections, poisons, some drugs, non-genetic cancers, liver, pancreas, uterine, heart disease or many other diseases can all cause kidney diseases.
The inherited conditions in Bull Terriers can occur in very young (less than six months) middle-aged or very old animals. Some dogs can be 10 years old plus and have the faulty gene in their makeup, pass it on to some of their pups, and may appear normal to their owners. These animals may live to a ripe old age with no one suspecting they have the diseases or have passed it on to their pups.
Signs of kidney failure that are common to both types of IKD and to other causes of kidney failure include the following:
-poor appetite
-dullness or lethargy
-weight loss or stunted growth
-poor hair coat
-vomiting/diarrhea
-foul breath and mouth ulcers
-muscle twitching and convulsions
-drinking excess water and passing too much urine – owners often notice an increase in the urine passed overnight.
-Pale gums (anemia)
-Dehydration (sticky dry gums)
There seem to be two types of IKD in Bull Terriers.
The first type is polycystic kidneys where the kidneys contain fluid filled cysts (or balls of fluid) which can be seen by looking at the kidney, for example by using an ultrasound machine, as black "holes" inside the kidneys. At what age this commonly is first detectable is unknown. While it is possible to detect the defect in some dogs as puppies, it may be that in animals it is not obvious until the dog is much older. In this disease a urine test will not pick all affected dogs, so an ultrasound examination is ideal.
The second condition is nephritis where the kidneys may look fairly normal until a biopsy (or small piece of tissue taken from a live animal) is examined under a microscope. It is not possible to diagnose this disease on the basis of only an ultrasound examination. A urine test or kidney biopsy are the best tests for this disease.
Both conditions are thought to be inherited by an autosomal dominant fashion, which means that only one parent has to have the fault for half the litter to be affected. If both parents have the fault three-quarters or more of the pups may be affected.
Because of the way these conditions are inherited, there is no point in condemning whole kennels or blood lines. As an affected dog may produce many unaffected pups and these animals do not have the faulty gene/s, these animals are fine to breed with as long as they are regularly tested. They have the virtues present in the lines but without the ‘taint’ of the faulty gene/s.
Dogs that have either of these inherited problems SHOULD NOT be bred from.
There is no test available that can say for sure that dogs are unaffected below one year of age. It is possible some affected dogs are not detected until they are 3 or 4 years old. Even leaving the ethical problems out of deliberately breeding affected dogs that must be euthanised or given to homes with the knowledge that they are affected by a deadly genetic disease, these dogs cannot be reliably cleared until they are at least 1 year old and possibly 3-4 years old. These dogs would have to be kept until this age before being bred.
Dogs affected by both these conditions may have bloody urine on and off, and the vast majority of dogs with nephritis and some of the dogs with polycystic kidneys will have abnormal levels of protein in their urine (this is shown by a high U P/C or urine protein to creatinine ratio). Only a few who are late in the course of the disease will have abnormal blood results. In both these conditions, how fast the disease progresses and how severe it is varies from dog to dog.
The Urine Protein to Creatinine ratio (U P/C) is a very sensitive test and is valuable in detecting nephritis and some polycystic kidney disease before signs of kidney failure appear (so lengthening the dog’s good quality of life) and hopefully before the dog is bred. Using this test will hugely decrease the nephritis problem within one generation. This is especially so as it is possible to prevent popular affected stud dogs spreading the faulty gene/s widely by detecting them much earlier than was possible before with the BUN test.
Animals with a high U P/C need to have a full urinalysis completed to rule out other causes than inherited kidney disease. If the U P/C is high and there are no other obvious causes (e.g. reproductive problems, bladder problems) an ultrasound examination and possibly a kidney biopsy will give the full answer.
The U P/C is easy to use and relatively cheap, making it an ideal screening test for nephritis. We believe most of those affected Bull Terriers have a high U P/C result by the time they are about a year old. There are possibly occasional dogs that are affected, that only have a high U/PC once they are 3-4 years old, but there are no published records of this. Lifetime retesting is recommended at this stage.
A lot more work needs to be done to investigate both these diseases. The relationship between these two diseases needs to be looked at, the value of current testing procedures needs to be continually monitored and, hopefully, in the future a genetic test will be developed that can be done once in young pups to predict which ones have the faulty gene/s.
There is no effective cure for either condition. Prevention by breeding dogs free of these inherited faults is the best solution.
At this stage palliative treatment to maintain comfortable life for as long as possible is the usual treatment for IKF.
If the kidney failure is recognized early in its course the following can be tried:
-constant access to fresh water.
-controlled protein, phosphorous and salt diet (use only with care in growing dogs).
-phosphate binders to bind phosphorous in the diet.
-water soluble vitamins (especially B vitamins).
-hormones for anemia.
-medication for nausea and stomach ulcers.
-blood pressure medication if necessary.