Cushing’s Disease in Dogs
What is Cushing’s disease and what causes it?
There are different types of steroids produced by the body, one of these is called cortisol. Cortisol is produced by two glands called the adrenal glands, which sit just behind the kidneys.
In Cushing’s disease, there is loss of the normal control of cortisol production leading to more cortisol circulating through the bloodstream than normal. This can be caused by either a problem in the pituitary gland (the control centre within the brain that tells the adrenal glands to produce cortisol) or the adrenal glands (where the cortisolis produced).
The most common cause of Cushing’s disease (85% of cases) is a small slow growing tumour in the pituitary gland, which disturbs the normal function of the gland.Some other causes of the disease are a tumours of the adrenal glands and benign enlargement of one or both of the adrenal glands.
What are the symptoms of Cushing’s disease?
If your dog is suffering from Cushing’s disease, you may notice some of the following symptoms
- An increase in thirst
- Increased frequency of urination
- A pot-bellied appearance
- Thinning of the skin
- Coat changes
- An increase in appetite
How is Cushing’s disease diagnosed?
Cushing’s diseasecan be a challenging disease to diagnose. When we suspect your dog maybe suffering from Cushing’s disease, we will carry out a blood test and urine test. These will enable us to help rule out other conditions that can have similar symptoms (such as diabetes and kidney disease). If the results of these tests increase the likelihoodyour dog is suffering from Cushing’s disease, then we will follow this up with one or twovery specific blood tests to check your dog’s cortisol levels. These will help confirm the diagnosis and also enable us to determine whether there is a problem within the pituitary gland or the adrenal glands.
If the results suggest there is a problem with the adrenal glands then we will usually carry out an abdominal ultrasound to examine both the adrenal glands in more detail.
In some cases we may also advise an MRI or CT scan to investigate the condition further.
How can Cushing’s disease be treated?
In most cases Cushing’s disease can be treated by daily capsules. These help to reduce the amount of cortisol in the bloodstream and should reduce your dog’s symptoms of the disease. Your dog will need to be treated with these for life and to ensure we are giving your dog the correct dose we will need to check your dog’s cortisol levels at 10 days, 4 weeks and 12 weeks after starting medication. Once your dog is stable we will usually recommend 3-6 monthly blood testing.
In some rare cases where the Cushing’s disease is caused by a tumour in one of the adrenal glands, we may recommend surgery to remove the diseased gland. This is a specialist operation and will be discussed with you in more detail if we feel it is indicated.
How will I know if my dog is feeling better?
On starting medication you should notice your dog’s symptoms improve and your dog should seem more like his/her old self. In some cases the medication can cause your dog to feel lethargic, have vomiting/diarrhoea or seem weak. If this happens you need to contact us immediately.
How will the disease progress?
Cushing’s disease can be successfully managed for many years. The length of time depends on the underlying cause and how well the condition is controlled with medication. For this reason, it is very important to perform regular checkups and blood tests to ensure we have your dog’s condition under the best possible control. Your vet will discuss this with you in more detail at the time of diagnosis.
The Swanbridge Veterinary Group, Tranby Lane, Swanland,HU143NG. Tel: 01482 633888, Fax: 01482 634 576, Email: