Adrenal-Based Dog Cushings Syndrome

Dog Cushings syndrome is caused by the excess of glucocorticoids in the body. Cushings disease in canines may be of two types: the adrenal based disease and the pituitary dependent disease. Cushings disease in dogs can be managed with medication.

Canine Cushings

Cushings disease in dogs may affect preponderantly middle aged and senior dogs. The disease is caused by an overproduction of glucocorticoids. All breeds of dogs may be exposed to the disease, both male and female dogs.

Types of Cushings

There are two forms of Cushings:

  • Adrenal based, less common, only present in around 20% of dogs with Cushings and is caused by the excessive secretion of glucocorticoids by the adrenal gland
  • Pituitary gland dependent hyperadrenocorticism (PDH), caused by an excessive production of the ACTH hormone, leading to an excessive secretion of glucocorticoids

Causes of Adrenal Based Cushings

The causes of adrenal based Cushings may include:

  • A tumor located on the adrenal gland (most common cause)
  • The administration of certain medications that stimulate the adrenal gland

In some cases, the causes of adrenal based Cushings are not determined.

Symptoms of Cushings

The adrenal based Cushings disease will develop slowly, but there will be some symptoms starting from the early stages of the disease. Watch out for symptoms such as:

  • Increased water intake, at least double the normal amount of water
  • More frequent urination, due to the increased glucocorticoids in the body
  • Elimination of urine in the home, if the dog's bladder is full and he cannot control it
  • Hair loss
  • Increased appetite and weight gain
  • Pot bellied appearance, may be due to the weakening of the abdominal muscles
  • Panting
  • Skin lesions

These symptoms may set in gradually and many owners may mistake these symptoms for old age signs.

Diagnosing Adrenal Based Cushings Syndrome

The adrenal based Cushings can be diagnosed through a number of clinical tests including:

  • A complete blood count, which can reveal an increased amount of glucocorticoids in the body
  • Dexamethasone suppression test
  • Urinalysis and the creatinine ratio in the urine
  • Ultrasounds and x-rays to detect possible tumors in the adrenal gland area
  • A biopsy of the tumor to establish its nature

Treatment Options

The excess of glucocorticoids can be lowered with medications. The medications will target the adrenal gland and the production of glucocorticoids. Trilostane is a medication that may be used and the dog will require a lifetime therapy. Periodic tests are required to monitor the dog's progress and to establish if the therapy is not causing major side effects.

In some cases, surgery will be needed to remove the tumor. Surgery may not always be possible, especially if the tumor is malignant and has already affected other areas of the dog's system.

If the disease is caused by the intake of certain medications that cause an overproduction of glucocorticoids, these medications should be stopped.