Ferret Adrenal Disease
Dr. Heidi Hoefer
Updated: September 24, 2014 Hair loss, resulting in bald spots
Adrenal gland disease is caused by hormone-producing tumors of the adrenal gland. It is an extremely common condition, most often affecting ferrets over three years of age. The adrenal glands are a pair of endocrine organs located in the abdomen near the kidneys. In this disease, one or both adrenal glands become hyperactive and start to overproduce sex steroid hormones, such as estrogens and androgens. The high level of hormones are then responsible for a myriad of symptoms including hair loss, anemia and urinary tract obstruction.
The adrenal gland tumors can be benign and slow growing, or malignant. Benign tumors secrete excessive hormone, but do not become large enough to compress other organs or cause symptoms typically associated with malignant cancer, such as weight loss. Malignant tumors can grow quickly and compress other organs, and cause weight loss, weakness and other systemic effects, along with secreting excessive hormones. The cause of this condition is unknown but may be related to the young age at which pet ferrets are often neutered or genetics.
Adrenal gland disease is only seen in both males and female ferrets. The incidence increases with age, making the majority of affected ferrets over three years of age. Younger ferrets can also develop the condition.
The hormones produced by this disease are responsible for most of the problems of adrenal disease. The most common effect is hair loss that may be subtle at first but typically progresses over time. Most ferrets are excessively itchy. Some of the hormones can cause enlargement of the prostate gland or other tissues around the urethra, resulting in trouble urinating, which can be life-threatening.
Because these hormones are sex-related hormones, like testosterone and estrogen, affected ferrets may develop signs of being "in heat." They may develop a bad odor, the male can become sexually aggressive toward the other household ferrets, and most females develop a swollen vulva.
What To Watch For
Increased body odor
Trouble urinating or defecating
Increased aggressive behaviors
There is no simple, single test to confirm adrenal disease, and many cases are diagnosed based on symptoms alone. Diagnostic testing is important; however, to determine if the tumor is malignant, to evaluate the overall health of the ferret, and to see if the adrenal condition has led to other complications.
Abdominal ultrasound (sonogram) is a relatively simple and safe test to evaluate the size of the adrenal glands and a test for prostate enlargement. This will also determine if the tumor is in right or left adrenal, which is important to know prior to considering surgical treatment. Monitoring the tumor with ultrasound is helpful in detecting potentially malignant tumors. Radiographs (X-ray's) are not as helpful.
Complete blood count (CBC) and platelet count are recommended to evaluate the activity of the bone marrow. Most veterinarians also run a plasma chemistry panel to assess overall health of the ferret and check for concurrent diseases.
Plasma hormone testing will confirm the diagnosis. However, this test is not always necessary to diagnose adrenal disease in ferrets. Symptoms and/or ultrasound alone are often sufficient.
Surgical removal of the affected adrenal gland(s) is the only permanent treatment for this condition, and is highly recommended if a malignant tumor is suspected. For benign tumors, medical therapy to counteract the effects of excessive hormone production is generally very effective. The most widely used of these drugs is Deslorelin (Suprelorin F®). This is an implant that blocks the effects of excessive hormones on their target tissues. Implants can work for 8 months or longer. A similar type of drug is leuprolide (Lupron®) but this medication typically only lasts 1-3 months. Both of these drugs may block f the symptoms of the disease (such as hair loss), but does not arrest the growth of the adrenal tumor.
Home Care and Prevention
Home care consists of careful, educated observation more than any particular remedy. Because ferrets with adrenal disease can have trouble urinating, both urination and defecation need to be monitored. A "constipated" ferret may actually be trying to urinate and not move bowels.
Any ferret unable to urinate for more than 6-8 hours should be brought to see a veterinarian immediately (that same day!). Complete urinary tract obstruction is a life-threatening emergency.
Because we have not fully identified the cause of adrenal disease in ferrets, it would be difficult to try to prevent this. Some people feel that early neutering is to blame and maybe pet ferrets should be spayed or castrated as young adults, rather than very young juveniles. However, even many older-neutered ferrets are susceptible to developing the disease in time.