Teeth are one thing to check if a ferret has intermittent swelling of his face.
Q: I volunteer at a ferret rescue. A foster mom has a 5-year-old, albino, male ferret. I have seen him and observed swelling of his ears and his face. The swelling comes and goes. Upon surrender to the rescue, the owner advised that he had allergies and advised only to use “Yesterdays News” litter. He currently is using pee pads. The rescue director, who has had ferrets for more than 20 years, the foster mom or myself cannot figure out what is causing the intermittent swelling. I am pretty good at online research and have not been able to locate many articles at all on immunodeficiency diseases in ferrets. The foster mom is feeding “Blue Kibble” and attempting raw feeding, as the rest of her troupe eats raw. What would you suggest as the first line of lab work to perform? Then what are your thoughts as to what the etiology of this swelling/edema of the ears (accompanied with a rash on ears) and face. It is important for careful consideration of a path to follow as the rescue is paying for all labs and treatments.
A: I agree with your assessment that intermittent swelling of areas of the face is very uncommon. I also agree that allergies and diseases of the immune system are quite rare in ferrets, except vaccine reactions. For those reasons, determining the cause of what you are seeing, as you have probably guessed, can take time and resources.
As a rescue organization, you may have the time, but resources (money) can be in a constant short supply, and this problem may tax the resources you have.
There are a few things to consider here as possible causes. As I mentioned, vaccine reactions are the main immune system reactions we observe in ferrets. Those reactions are usually immediate and result in vascular and gastrointestinal system distress. Rarely does a vaccine reaction cause facial swelling, something that is more common in dogs and cats. When a vaccine in a ferret does cause facial swelling, it occurs soon after vaccination and then subsides, it is not intermittent as you report.
Could this be a very unusual immune system reaction to something in the environment? Possibly, but it is something that would be considered unusually rare in pet ferrets.
A carnassial tooth root abscess can fill with purulent material causing the face to swell. In most cases, the facial swelling does not subside until the abscess is lanced and treated. In rare instances, the lining of the abscess can burst into the oral cavity causing the facial swelling to decrease in size all by itself, without any human interaction. In a short time (days), the opening to the oral cavity heals and the abscess again fills up with purulent material and when the pressure in the abscess becomes overwhelming, an opening will again occur in the oral cavity and the process repeats.
Finally, I would never rule out cancer, as cancer can do just about anything.
But what can you do for this ferret? First, it may be most productive to investigate this problem when the face and head are swollen, not when the ferret appears normal. A very thorough examination of the oral cavity and dentition could help rule out an abscess. When the face is swollen, a fine-needle aspirate of the swelling could help determine if the swelling is tissue or liquid (as would be the case in an abscess). A complete blood count might reveal a high white blood cell count if this is due to an abscess. Finally, while this is swollen, a radiograph of the skull and thorax might be useful. Why the thorax? I have seen masses in the very upper aspect of the thorax “block” lymphatic and/or blood flow back to the thoracic cavity leading to swelling of the neck and aspects of the head.