Cushing’s disease, also known as Hyperadrenocortisicm and Hypercortisolism is a disorder of the pituitary and adrenal glands. Cushing’s disease develops as a result of overproduction of corticosteroids from the adrenal glands. This condition is becoming excessively common in pets. While the predominant victims are dogs, cats although rare, are also susceptible to develop Cushing’s disease. Cushing’s disease is named after an American Neurosurgeon Harvey Cushing who detected and described the disease for the first time in 1932, when a woman suffering from this disease approached him. This disease mainly affects adult dogs and commonly appears from an age of 6 to 12 years. However, Cushing’s disease may also affect young dogs.
What Causes Cushing’s Disease
Cushing’s disease is the cause of overproduction of corticosteroids (cortisone and cortisol). Although a normal level of corticosteroids in the blood is vital for proper functioning of the organs and the body as a whole, overproduction leads to several complications, which can be termed as symptoms of Cushing’s disease. Some of associated symptoms of Cushing’s disease are abnormal hair fall, calcium deposits in skin, pot bellied appearance, abnormal weight gain, fatigue, panting and shortness of breathe, excessive urination and increased thirst, increased appetite, weakness and high blood pressure.
Corticosteroids are vital for bodily functions. While normal level of corticosteroids maintains immunity, excessive production weakens the immune system and makes the body more susceptible to infections and other diseases. Other than maintaining a healthy and active immune system, corticosteroids are also considered vital for a number of other bodily functions like proper functioning of the brain, regulation of metabolic process, mobilization of body fat, muscle formation and support, bone health and kidney health. Abnormally high production of corticosteroids flips the bodily functions and creates havoc instead of supporting the life system. This is the reason why dogs suffering from Cushing’s disease display symptoms like leaner legs, scarce coat on body and over-absorption of calcium.
The generation of corticosteroids is a two way mechanism, in which the pituitary gland, located just below a dog’s brain identifies the necessity of production of corticosteroids and gives command to the adrenal glands located just above the kidneys of a dog. The pituitary gland signals the adrenal glands by releasing its own hormone, which in turn makes the adrenal glands produce corticosteroids. However, this is not a continuous process and is carried out only when necessary. The problem generally erupts in case of a tumor formation in the pituitary gland or the adrenal gland. Dogs suffering from adrenal gland Cushing’s disease are most likely to be diagnosed with the disease at a slightly later age (11-12 years). While pituitary Cushing’s disease are common with smaller breeds, the larger breeds are mostly diagnosed with adrenal gland Cushing’s disease. Dogs suffering from adrenal gland tumors can be cured by removing their cancerous adrenal glands. However, if the possibility of doing that doesn’t exist anymore, the dogs are subjected to more medication than the dogs which suffer from pituitary gland Cushing’s disease.