Cushing’s disease (which is also known as Hyperadrenocorticism), is a common hormonal syndrome that occurs when the body makes too much of the stress hormone cortisol. It is generally caused by a tumour of the pituitary gland within the brain (in approximately 85% of cases), or adrenal gland tumours (in approximately 15% of cases). Although rare, long term use of glucocorticoid medications can also cause Cushing’s disease.
The physical signs that your pet may have this disease are:
- Increased thirst and urination
- Lethargy or weakness
- Recurring skin or bladder infections
- A ‘pot-bellied’ appearance
There isn’t one specific test that is perfect for diagnosing Cushing’s disease and often, a combination of tests may be necessary. The following tests can all be performed in house at our clinic and your veterinarian will choose which of these will be best suited to your pet:
Urine cortisol:creatine ratio
This test is convenient as it only requires a urine sample, ideally collected at home in a stress-free environment. If the test result is negative, your pet does not have Cushing’s disease; if the result is positive, further testing to confirm the diagnosis is needed.
Low-dose dexamethasone suppression test
This test involves leaving your pet in hospital for the day as our veterinarian measures how your pet responds to administration of a steroid by assessing their cortisol levels throughout the day. This test can also help determine what part of the body is causing the disease.
ACTH stimulation test
In this test we will measure your pet’s baseline cortisol levels, then administer ACTH and measure the cortisol response after one hour. Patients with Cushing’s disease will have exaggerated cortisol levels in response to ACTH.
Why and how do we treat this disease?
Diagnosing and treating Cushing’s disease will make your pet feel better and reduce risks of further medical concerns associated with long-term high cortisol levels. Treatment can also prolong your pet’s life.
If your pet is not treated for Cushing’s they are more likely to suffer from:
- Hair loss and skin infections
- Urinary tract infections
- Kidney disease
- An increased chance of getting blood clots
- High blood pressure
Treatment involves medial therapy targeted to reduce cortisol levels in the body. In some cases, surgery may be recommended to remove the tumour producing excess cortisol. Our veterinarians will provide further information about treatment options available and work with you to develop an individualised treatment plan for your pet.