What is the prognosis for an animal diagnosed with Cushing’s disease?
The prognosis for pituitary dependent Cushing’s disease with treatment is usually good. Some signs will disappear quickly and others gradually. Appetite and water consumption usually return to normal in a few weeks, but full return of fur lost may take several months.
With pituitary surgery, roughly 85 to 95 percent of dogs who have the tumor removed no longer have a hormonal imbalance or neurological symptoms. For dogs with adrenal tumors, surgery can be potentially curative. Treatment of one type of Cushing’s disease, either pituitary or adrenal, does not prevent the development of the other form of the disease.
What are the common symptoms of Cushing’s disease?
There is no single test to diagnose Cushing’s disease. A patient’s history, physical exam, and results of initial blood and urine tests often provide a strong suspicion for the presence of the disease. One of the first tests for Cushing’s disease is the urine cortisol/creatinine ratio test. Dogs with normal cortisol/creatinine ratios likely do not have Cushing’s.
Dogs with high cortisol/creatinine ratios will require a low-dose dexamethasone suppression test. Dexamethasone is used to suppress cortisol levels. If a dog’s cortisol levels are not suppressed it is likely the dog has Cushing’s disease. Patients with Cushing’s disease may also have an enlarged liver or enlarged adrenal glands. Your veterinarian may take X-rays or use ultrasounds to check the liver or adrenal glands, as well as an ACTH stimulation test to determine if the adrenal glands are functioning properly.
Lifelong oral medication is often prescribed for pituitary dependent Cushing’s disease to help manage the symptoms. The most common drugs used to treat Cushing’s disease are Trilostane and o,p’-DDD (also called Mitotane or Lysodren). For pets with adrenal dependent Cushing’s, these drugs are not as effective in reducing symptoms.
Radiation may also be used to shrink the size of a pituitary tumor. This treatment is most effective on small tumors to help reduce the symptoms of pituitary dependent Cushing’s disease.
Adrenal dependent Cushing’s disease is treated by surgical removal of the affected adrenal gland. Adrenal gland tumors, if cancerous, can spread to other parts of the body if the cancer is not removed by surgery. Surgical removal of the tumor generally eliminates the need for lifelong medication.
Does Cushing’s Cause Blindness in Dogs?
Dogs with Cushing’s Syndrome are at an increased risk for going blind. A side effect of this condition includes immunodeficiencies that lead to a high risk of corneal disease. Both conditions can cause a dog to lose their eyesight. There are similarities and correlations between dogs with Cushing’s and dogs experiencing sudden blindness from SARDS. The main difference between the two is that there are some treatments available for dogs with Cushing’s, whereas SARDS has no known cure.
Dog Cushings Disease. Dr. Dan covers symptoms, diagnosis, and treatment of Cushing’s disease
Cushing’s Disease, also known as Cushing’s Syndrome and hyperadrenocorticism, is a condition that causes a dog’s adrenal glands to overproduce cortisol. This is caused by either a tumor in the pituitary gland or the adrenal gland. Too much cortisol lowers a dog’s immune system, predisposing them to infectious diseases. It also causes muscular weakness, weight gain, and increased drinking and urination and can leave dogs at a greater risk for other health conditions as well.
Most dogs with Cushing’s Disease are over the age of 6 when they are diagnosed, although the condition can impact younger dogs as well. Cushing’s can impact cats as well, but it’s less common in cats.
Cushing’s is more common in females than males. While Cushing’s can affect any dog, there are specific breeds prone to developing Cushing’s Disease, including: