Questions
- What is Cushing's disease?
- Signs & symptoms of Cushing's Disease
- How to treat Cushing's Disease
Cushing’s disease is a common hormonal illness in older dogs that can affect their quality of life. Early detection and treatment can provide significant benefits for your four-legged friend. Read on to learn about how Cushing’s disease presents itself in dogs, how to recognise the symptoms and how it can be treated.
What is Cushing's disease?
Cushing’s disease is an endocrinopathy or hormonal disease, that results from the overproduction of the hormone cortisol. The technical name is Hyperadrenocorticism and it commonly affects older dogs, as well as humans and horses. It occurs when the body produces too much cortisol, leading to a range of uncomfortable symptoms.
Cortisol is a natural steroid produced by the adrenal glands and it affects every tissue in the body. Cortisol’s functions are wide-ranging and it plays a role in metabolism, blood sugar control, inflammation, and the stress response. The amount of cortisol released by the adrenal is closely regulated by the pituitary gland, a small pea-sized structure deep in your dog’s brain. Cortisol levels fluctuate through the day and through life, but prolonged and excessive cortisol can start to wreak havoc.
So why are your dog’s adrenal glands making too much cortisol in the first place?
This happens for one of three reasons:
- Pituitary Cushing’s Pituitary-dependent Cushing’s occurs due to a growth, or tumour, in the pituitary gland. This causes the gland to malfunction and it keeps sending messages to the adrenals to produce more and more cortisol. These little tumours can be benign or malignant and are responsible for over 80% of all cases.
- Adrenal Cushing’s In this form, a tumour develops in the adrenal gland which directly causes the release of excess cortisol. Less common than pituitary-dependent Cushing’s, adrenal tumours are responsible for under 15% of cases.
- Iatrogenic Cushing’s The last type of Cushing’s occurs due to an overconsumption of oral steroid medications. Steroid medications, like prednisolone, are commonly used for many inflammatory conditions, however, too many oral steroids can override the normal internal message systems. The only type of Cushing’s disease we can prevent is Iatrogenic. The pituitary and adrenal types are not preventable, nor can we predict which dogs may develop the disease. Cushing’s requires lifelong management but luckily early detection and treatment can make a huge difference.
Signs & symptoms of Cushing's Disease
All the signs and symptoms of Cushing’s disease in dogs result from prolonged and excessive cortisol. They can sometimes be hard to spot in the early stages where your dog may not seem unwell. The classic signs can include:
- Increased thirst
- Increased urination
- Increased hunger
- Panting
- Potbelly
- Thin haircoat and skin
- Skin pigment changes
- Recurrent infections
- Abnormal fat distribution, especially around the tail base
- Lethargy or weakness
We can’t predict how slow or fast the disease may progress. Some dogs live for many years with mild symptoms of Cushing’s disease, and others will become very unwell over a short space of time. As most dogs are diagnosed when they are older, many will have concurrent illnesses and age-related changes.
The final stages of Cushing's disease in dogs will be different for every patient. There may be uncontrollable thirst and urination, severe infections, weakness or collapse. Some dogs experience vomiting and diarrhoea. The main thing we need to always keep in mind is our furry friend's quality of life.
If you are concerned your dog has some of the above symptoms, book an appointment with your vet as soon as possible.
Diagnosis
To diagnose Cushing’s disease in dogs a few tests need to be undertaken. Initial blood and urine screening will be recommended to check your dog’s overall health. You may hear the terms ACTH Stimulation test or Low Dose Dexamethasone Suppression test. These special blood tests measure your dog’s production of cortisol and confirm the diagnosis of Cushing’s syndrome.
Depending on the results, your vet may also recommend an abdominal ultrasound to visualise the adrenal glands and other organs.
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How to treat Cushing's Disease
Treatment for Cushing’s disease is widely available and can significantly improve your pup's daily life. The treatment recommended will depend on which type of Cushing your dog has.
Treatment options include:
- Oral medication
These tablets aim to suppress cortisol production in the adrenal gland. They need to be given regularly for life.
- Surgery
In some select cases, surgery can be used to remove an adrenal tumour.
Cushing’s disease requires lifelong management and cure is rarely achieved. The majority of cases are treated using oral medication.
To monitor treatment your dog will need regular blood tests to check their ongoing health and level of cortisol production. This monitoring is very important, as a side effect of treatment can be the development of low cortisol, a life-threatening complication.
Dog breeds prone to Cushing's Disease
Although any dog can potentially develop the syndrome, some dog breeds are prone to Cushing’s. These include the miniature poodle, miniature schnauzer, boxer, beagle, and bichon frise.
In most cases, Cushing’s is diagnosed in middle-aged to older dogs and is more common in smaller breeds.
If you’re concerned your dog has Cushing’s disease, speak to your local vet today.