Cushing’s in dogs
Cushing’s is a hormonal disease state caused by the excessive production of cortisol, one of the “fight or flight” hormones produced by the adrenal glands.
Normally, when the cortisol level of blood is low, a gland in the brain (called the pituitary gland) secretes a stimulating hormone (ACTH) to tell the adrenal glands to produce and release more cortisol. Once blood cortisol levels are high enough again, it inhibits further secretion of ACTH by the brain. In this way the body keeps blood cortisol levels balanced.
The presence of excess cortisol can come about in three ways:
1. A tumour of the gland in the brain (the pituitary gland) – in this instance high levels of cortisol no longer inhibit the production of ACTH and results in over stimulation and secretion of cortisol by the adrenal glands.
2. A tumour of the adrenal gland/s – cortisol is produced regardless of ACTH not being secreted.
3. Administering too much cortisone as a medication.
Most common symptoms in your pet:
- Drinking large amounts of water and urinating a lot
- Eating a lot and always hungry.
- Pot belly
- Symmetrical hair loss, especially over the sides
- Thin tummy skin with very visible blood vessels
Why is it a serious condition:
- If the condition is caused by one of the two tumours previously mentioned, the tumour itself will eventually pose a problem either in the abdomen or brain. Tumour cells could also spread to other organs
- It could cause pulmonary thromboemboli – small blood clots that block blood vessels in the lungs. These little emboli can also affect blood flow to other organs
- Predisposes to Diabetes Mellitus
- Causes reduced liver function
The prognosis depends on the type of Cushing’s, the age and general health of the animal, any other disease processes present and treatment.
Even though surgery is described it is not recommended. Treatment mostly consists of an oral tablet called Vetoryl, which inhibits the production of cortisol. This will resolve some of the symptoms and make the patient much more comfortable.
Life expectancy can vary from as little as 12 months to 5 years (mainly in younger patients in which treatment is effective).