Canine Cushing’s Disease

Cushing’s Disease is one that affects dogs but many people don’t really know very much about it. As a result it often goes on without any one recognize that their dog has it. While this particular disease mainly affects older dogs, it has been known to affect younger ones as well. However, when it does occur in older dogs most of the time the owner’s think that what they see is a natural pattern of their dog slowing down. Since this isn’t uncommon as an animal gets older they don’t see it as a cause for alarm.
include weight gain or loss, hair loss, and losing the control that they used to have over their bladder. Some owner’s do see such changes in their older dogs though that they consider putting them to sleep. They are torn between their desire to enjoy their pet and to keep them from suffering as they become older and have less control over their bodies.

If your dog is really suffering from Cushing’s Disease though rather than old age, there is a good chance it can be resolved. This means your pet would have a chance to live a healthy and happy lifestyle once again. Knowing that such a condition does exist will help more dog owner’s to seek treatment when those early signs of it appear. Being informed about what your dog should be doing if it is normal and healthy is very important. It also means that little chances will be recognized very early when the intervention can help the most.

In order to fully understand all of these changes we need to talk about some things that take place for a normal dog. There is a pituitary gland located at the base of the brain. Here the hormone known as ACTH is produced with the full name being Adrenocorticotrophic. The Hypothalamus is another region of the brain that is responsible for regulating it. The ACTH should be made and then allowed to be released into the blood circulating through your dog’s body. As a result of it being in the blood, there are two adrenal glands located around the kidneys. They produce what is called Glucocorticoid which is a type of substance very similar to cortisol.

This is important as Cortisol allows your dog to take care of many daily needs. For example it will help them to deal with the various types of stress that they encounter. It also plays a key role in regulating blood sugar levels, the metabolism for fat, the development of the skeletal muscles, functioning of the kidneys, the central nervous system, the cardiovascular system, and the overall benefits that are offered by the immune system.

However, the amount of Cortisol in the body has to be regulated and in balance. If you have too much of it your body will store the foods you consume as fat. You will be more likely to suffer from infections as well as experiencing pain. This is true for both humans and for dogs. When they don’t get enough Cortisol in the body then there will be too much ACTH throughout the blood. Keeping these levels all balanced is important for your dog to be as healthy as possible.

A dog with Cushing’s Disease has something that in that cycle that isn’t where it should be. There can be many different factors that cause something to be out of cync. For example your dog could have a tumor located in the pituitary gland or even an adrenal tumor. Even some of the medications given over the counter or that are prescribed by the vet for other medical concerns can cause there to be too much of the Cortisol found in the bloodstream. Your dog won’t be able to regulate the production of it on its own either as long as the other factors are still in place.

Why do Dog’s get Cushing’s Disease?

There are quite a few different reasons why dogs get Cushing’s Disease. Being well aware of them can help you to keep your eye out for potential problems that your dog can suffer from. As I mentioned, a tumor can develop in the pituitary gland. This is the most common reason why this disease occurs. The body of your dog will then be making too much of the ACTH. The adrenal will tell it not to but those commands will be ignored.

The size of the pituitary tumor can vary but most of them are about 3 millimeters or smaller. Yet they are very powerful when it comes to getting the production of ACTH and Cortisol out of balance. This is the reason for Cushing’s Disease for approximately 85% of dogs that develop it. The remaining 15% of them are larger in size and they are much harder to remove. That are more than 1 centimeter are referred to as Macroadenomas.

These are very dangerous due to where they are located. The pressure from them pushes against the tissues and the nerves of the brain for your dog. This is why some of them will end up with poor eyesight or even going completely blind. Many owner’s also see the loss of sight as a natural part of aging for their pet though. Depending on where the tumor is applying pressure, a dog may experience neurological problems as well.

Should such signs appear it is a good idea to take your dog to the veterinarian. However, not all of them are well trained to look at Cushing’s Disease as a potential cause either. They too often see the parallel between the symptoms a dog shows and old age. However, with your encouragement they can complete a variety of tests to find out what is really going on. You will find many well trained vets out there though that do know Cushing’s Disease is a possibility. They will do all the can to find out for sure what is creating the problems for your dog.

Should an adrenal tumor be present then the body is going to be creating more Cortisol than your dog needs. The odds are about 50% that the tumor could be cancerous or not. That is why early intervention is so important. These adrenal tumors can be extremely aggressive if they aren’t immediately dealt with. Sadly, many dogs suffer permanent damages to their liver and the lungs due to a diagnosis not being made soon enough. As a result the messages that the pituitary glands send to the adrenal glands can’t be decoding like they should. The result of this is that the level of Cortisol products continues to increase.

It is very likely at that point one of the adrenal glands is much bigger than the other. The larger one will be where the tumor lies. The other can either stay at the normal size or it may be much smaller than it should be. This type of size difference is red flag that Cushing’s Disease may be present. Approximately 15% of cases are diagnosed due to the owner’s or the vet noticing this aspect of the dog’s body being out of proportion.

A dog that is given too much Glucocorticoid can also suffer from Cushing’s Disease. There are many different types of allergies that dog’s can suffer from. To help treat them, a vet may suggest the use of Glucocorticoid. While they can be useful, regular exams and check ups at the vet office while using them is extremely important. That way the pituitary gland and the adrenal glands aren’t fighting a losing battle to get the levels of ACTH and Cortisol balanced.

There are particular types of steroids such as Prednisone that your vet may recommend for your dog. If that is the case the dose should be tapered. Rather than a dose offered daily a dose should be given only every other day. Most of the time dog’s that suffer from Cushing’s Disease for this reason have small adrenal glands. For the most part all that will be needed to cure the problem though is to change the medication or to cut back on the amount of it. Finding the right dose or the right medciation to take care of a certain medical concern though can take plenty of trial and error though.

All breeds of dog’s have an increased risk of developing tumors as they get older though. This is one more reason why you will find that it is mainly older dogs that suffer from Cushing’s Disease. With more education about the disease though there are quite a few middle aged dog’s now being treated for it as well though. On average the age is about 10 years though for those that have Cushing’s Disease.

The statistical information relating to this disease seems to have some controversy associated to it. Depending on the materials you read, you will hear that the risk is even for both male and female dogs. Other materials claim that females have a higher risk. One area that everyone seems to be agreeing upon though is that both spayed and neutered dogs seem to have a higher rate of Cushing’s Disease.

There have been reported cases with every single breed of dog out there. However, some studies indicate that certain breeds are more suspectible to it than others. It is believed this could indicate some time of genetic link with Cushing’s Disaese. Yet it is important to realize that is just one of many factors that are known to be associated with it. Small dogs that are under 44 pounds when full grown account for approximately 75% of all cases of Cushing’s Disease.

Some of the breeds that have a known high risk include:

Beagle
Boston Terrier
Boxer
Daschund
German Shepherd
Golden Retriever
Poodle
Scottish Terrier
Yorkshire Terrier

Make sure you are Aware of the Symptoms of Cushing’s Disease

Part of helping your dog to make a full recovery from Cushing’s Disease is an early intervention. When you are well aware of the symptoms of it you will have a better chance of doing so. There are many different types of symptoms that can be expressed when your dog has this disease. Most of them come on slowly though rather than overnight so that is why so many people chalk it all up to nothing more than old age. The speed at which the disease progresses will vary for each dog. The average though is approximately 6 years. However, by then it is often too late for a recovery to occur.

The particular symptoms that any dog with Cushing’s Disease will exhibit will vary in severity. The number of symptoms that are present will also vary by dog so don’t assume your dog is fine due to a lack of many such symptoms being identified. One of the most common symptoms is drinking more than usual. Each dog has its own amount it usually drinks so this amount of water that they drink will really only be recognized by someone that routinely offers the supply of it.

Now if your dog drinks more water one day that the next that really isn’t a reason for alarm. With Cushing’s Disease we are talking about a significant change in their drinking habits. Any range from twice as much as usual to ten times as much have been identified by dog owners. This symptom seems to be found in at least 85% of those dog’s diagnosed with it.

Of course the more that they drink water the more that they will be urinating as it runs through their system. If you have an indoor dog that has always done a great job of going to the bathroom outdoors you may notice changes there. They may start to urinate several times a day all over the house due to the inability to control their bladder.

One of the reasons why most dog owner’s don’t think there is a problem other than old age though is due to the appetite. Approximately 80% of those with Cushing’s Disease end up consuming more food than they did in the past. You may notice their dish is empty sooner so you just refill it. Many of them also will eat food you leave out for other pets or dig through the trash when they didn’t before.

Take a very good look at the abdominal area of your pet. If you notice it becoming enlarged then that is a sign something is wrong. It is believed that about 80% of dogs with Cushing’s Disease exhibit an enlarged abdominal region. Of course it is also reasonable to automatically make the connection that they are gaining weight there due to the extra food and water that they are consuming. Again, this is a common reason why dog owner’s discount that anything may be wrong that requires medical attention.

Since each dog will have a unique shape to the abdomen, you should keep an eye on this area of your pet often. Should you see it becoming larger you will want to contact your vet right away. This is an indication that deposits of fat have moved from one place to another on the body. As a result the muscle mass your dog has will be decreased. The skin will become thinner too which is why hair loss is so common when a dog has Cushing’s Disease. The statistics relating to this symptom are varied as well from 50% to 90%.

Even if the other symptoms of Cushing’s Disease go unnoticed, the additional loss of hair is something that they do notice. It can often trigger alarm with many pet owner’s as well. You will easily be able to tell the difference from normal shedding and extreme hair loss associated with this type of disease. There are various areas of the body where it will be most noticeable including the:

Abdomen
Elbows
Flanks

From there the hair loss will continue to all the other areas of the body. This thinner skin also makes your dog more susceptible to other problems. For example they are going to be more likely to get cuts and scraps through the skin. They can suffer from sun damage and they are going to be more susceptible to various types of illness than in the past.

There are a handful of other symptoms that have been reported with Cushing’s Disease as well. By paying close attention to the normal behaviors of your beloved pet, you will be more likely to identify such changes immediately. You also now have the knowledge to question what is taking place as beyond just the normal aging process. These additional symptoms include:

Excessive panting
Frequent urinary tract infections
Unable to product offspring

How can I get my Dog Tested for Cushing’s Disease?

Testing is the only way to find out for sure if your dog has Cushing’s Disease or not. Your vet should be willing to do this for you if you request it should they not think of the process on their own. If your vet doesn’t offer such testing or tells you it isn’t necessary then try to find another vet that will perform such testing for you. Make some calls or search around online to find what you are looking for. The testing can be costly though because a blood count needs to be done, the chemistry make up of the dog’s body, and a urine test so that the right diagnosis can be completed.

The medical history of the dog will be evaluated as well. If you have the same vet that has always cared for your dog they will have such records. Otherwise you need to be able to provide as much information as you can about what has taken place health wise for your pet over the years.

Once the initial results from such testing come back the vet will likely still have more to consider. If any of these three tests come back with inconsistencies or readings that aren’t normal other testing will be done including checking the enzymes in the liver, the cholesterol in the body, and determining how well the kidneys are performing their basic functions. Additional testing that could be conducted include checking the level of Cortisol that is in the urine, reviewing the cartinine ration, and even an ultrasound.

You will have some role in all of this as well so make sure you pay close attention to what the vet asks of you. For example if they want to test the amount of Cortisol in the urine you will be asked to collect samples at home. Then you will take them to the vet’s office to be tested or they will ship it out to a lab that performs such tasks for you. It is very common for this particular type of test to be done first. Then the additional tests can be requested depending on what those initial results are.

A type of test called Dexamethasone Suppression is also very common. When a dog is healthy they will be able to handle a low dose of it. This is going to reduce the amount of Cortisol that is found in the bloodstream over the course of the 8 hours after they are given it. However, should the dog have Cushing’s Disease they won’t have that reduction in Cortisol level due to the way that their body is producing it.

While an ultrasound for your dog can be very high priced, it is one of the best tools that vet’s have for examining all the details of the abdomen. They are able to see the specific shapes of the internal organs and the adrenal glands. They can also see the size of these aspects of the insides of a dog. If there a tumor in the body it will show up with the ultrasound. The size of it can be identified with the ultrasound so that is very valuable for determining the best course of treatment available.

If the ultrasound shows that your dog has a tumor in the adrenal glands, it is going to need surgery if there is a chance for it to get better. If the vet can successfully remove it most of the time such tumors won’t grow again. Therefore your dog would have an excellent chance of making a recovery and going back to his or her old self. Many vets take preventative measures against Cushing’s Disease during the recovery period. They offer Ketoconzaole to help reduce the risk of it developing.

Studies indicate that a dog is at risk of developing Cushing’s Disease when they are given Adrenalectomies. Since at least 50% of adrenal tumors don’t create cancer, an owner may decide against the surgery. This is often the case if such tumors are found in vital organs including the liver and the lungs.

Should there be tumors found in the pituitary glands, surgery won’t be a form of treatment offered. This is because such tumors are extremely small in size. They also won’t be very aggressive when it comes to the growth patterns. Therefore the risks involved with the surgery are more than the benefits available for your dog. Your vet will keep a close eye on your dog though and may even suggest radiation as a form of treatment.

The radiation is often a good treatment choice if your dog is suffering some type of neurological damages due to the pressure from the tumors against areas of the brain. By reducing the size of such tumors though the pressure is reduced. It may be enough to reduce or completely eliminate those neurological concerns. The biggest problem though is that radiation treatments like this cost several thousands of dollars. Most people simply can’t afford to pay for that type of treatment for their beloved dog.

While the procedure isn’t nearly as common, some vets will also perform a Dexamthason Suppression test. That way they can find out if it is the pituitary or the adrenal glands that are affected due to the Crushing’s Disease. A test that was common in the past but isn’t really offered much anymore is called the ACTH stimulation test. It isn’t often used due to the high price involved. Instead the vets would rather rely on other methods of testing that are just as accurate yet more affordable. Sometimes it will be done though if the results from the other types of testing still leave the diagnosis unclear.

You will find that there are quite a few different types of drugs that can be used to help treat Cushing’s Disease if your dog is diagnosed with it. Lysodren is the one that is most popular due to how it works and the affordable cost of it. Lysodren works by killing the adrenal cortex tissue. This is very important as that is where Glucocorticoid hormones are produced. After about 7 days of treatment with Lysodren most dog’s will test with a lower level of Cortisol in their blood than before. The closer they get to things being in balance again the fewer symptoms of Cushing’s Disease they will continue to show.

Lysoden is also effective when the pituitary glands are making excessive amounts of ACTH. This is a constant cycle to deal with because when there is more ACTH then the body will be making more Cortisol. After a course of 7 days with Lysoden though this pattern of activity can be successfully interrupted. The dose will then be reduced to only 1 or 2 times per week depending on the needs of the dog. For many dogs though getting a dose every other day or every day has to be done in order for them to keep this balance in their bodies.

While Lysoden can work well for the treatment of Crushing’s Disease, there are some downfalls of it as well. This particular drug has been associated with a variety of side effects that can be quite extreme for many dogs. For example it can destroy much more of the adrenal tissues than it should. As a result your dog may develop what is known as Addison’s Disease. This will occur for approximately 5% of dogs that are given Lysoden.

Some critics are quick to judge vet’s for the use of Lysoden though. They feel that they deliberately try to make some dogs sick with Addison’s Disease so that they can charge fees to care for that as well. The treatment for it is quite extensive including steroid hormones that must be injected on a daily basis. Without such treatment though your dog will surely die. Of course it is fair to say that most vets aren’t out for your money like that – so they will explain the possible outcomes with the use of Lysoden from the start.

Not all dogs will respond like they should when given Lysodren. What will occur is that the level of Cortisol in their bloodstream will be less than it should. Statistically, about 1/3 of the dogs that are given Lysodren will have this adverse reaction to it. Approximately 1% of them will die as a result of the extreme side effects that come with it. They include:

Diarrhea
Nausea
Vomiting
Weak Muscles