Adrenal disease is primarily found in ferrets over 3 years of age, but has been seen as early as 9 months. Clinical signs can be any combination of the following: hair loss, either just on the tail or symmetrically over the body, periodic shedding of the complete coat with full re-growth each season, itching between the shoulder blades, generalized itching, weight loss, lethargy, enlarged vulva and heat activity in spayed females, aggression and mating behavior in neutered males, urinary straining and/or blockage in males.

If you suspect that your ferret has adrenal disease, what do you do? In general, surgical removal of the tumor is the best choice in a healthy ferret. Ninety percent or more of affected ferrets can be cured by surgery. Even older ferrets (>7 years) can do well after the affected gland is removed, though caution should be taken with these geriatric cases. Post surgical sudden death is far more common in ferrets >6 years of age. An exploratory surgery may also reveal other problems, including intestinal foreign bodies, insulinoma, hypersplenism and/or lymphoma. Supportive care is extremely important before, during and after surgery. The majority of these surgeries are uncomplicated. Approximately 10% will be complicated, involving the removal of both adrenals or resection of a portion of the vena cava. It is highly recommended to biopsy the tissue to determine that diseased tissue has indeed been removed. Treating your ferret for adrenal disease requires case by case consideration as there are often differences in anatomic presentation.

In the event that your ferret is not a good surgical candidate or lack of money prevents surgery, Lupron (leuprolide acetate) is the most common medical treatment. There are 2 forms that are used, a 30 day depot and a 4 month depot. There is also a daily form available for humans, it is not effective in ferrets. Lupron is often given before surgery to decrease complications and it can also be used in ferrets with bilateral disease where both entire glands could not be removed as a post-operative treatment.

Melatonin also used to decrease the effects of adrenal disease. While it can be given in an oral form daily, the implant is easier and more effective, though it needs to be replaced yearly. Lupron and melatonin can be used simultaneously.

The best medical treatment for your ferret should be chosen after thorough discussion with your veterinarian.

There have been several anecdotal stories regarding various herbal, nutritional and environmental changes to alleviate adrenal disease. Until these methods have been scientifically tested, I reserve judgment on their use, leaving that decision to each owner and their veterinarian.

NOTE FROM FERRET WISE
Dr. Weiss wrote this post on July 26, 1998, for FML and FAIML readers and their veterinarians.

I have performed about 10 of these procedures to date. All the ferrets have survived and are doing well. In my opinion vena cava ligation can be a life saving technique which should be performed with select cases. The right adrenal gland in the ferret is normally attached to the vena cava, which makes it a technically difficult surgery. Although difficult, an experienced ferret surgeon usually can perform this procedure without ligating the vena cava, with very good success. I do not feel the vena cava should be ligated routinely, or because the adrenal tumor is "attached" to the vena cava (it is virtually always attached to the vena cava). On occasion we see very large right adrenal tumors which almost completely occlude (obstruct the blood flow through) the vena cava. In these cases the tumor grows over weeks or months slowly occluding more and more of the blood flow through the vena cava. When this occurs over this time frame the body develops collateral circulation (other small new blood vessels that bypass the vena cava). Therefore when the vena cava is almost completely occluded I feel it is usually safe to ligate it in the ferret. The other alternative is closing the ferret up and calling it an inoperable tumor (which is giving the ferret a death sentence). With the option of vena cava ligation virtually all adrenal tumors are operable. This is really a benefit to the patient since even malignant adrenal tumors rarely spread and complete removal is usually curative.

When used appropriately I feel this is a life saving technique which has minimal complications. But, it's important to remember that a ferret with a large adrenal tumor is a very ill animal (even if it comes on so slowly that the owners do not notice many symptoms). Although this is a very stoic species which does not always display pain as we do, this is a life threatening condition. In a case like this there are always risks associated with anesthesia and surgery, because it is such a serious condition. In my opinion, in such a case, surgery with vena cava ligation is the best chance to save the patient's life and give the ferret a good quality of life post- operatively.

Charles Weiss, DVM