Young ferret

Ferret

Disseminated idiopathic myofascitis (DIM) is a disease of unknown cause in pet ferrets that targets their muscle function. Ferrets affected by DIM are usually less than 18 months old, however, some cases have been seen in adults over 2 years of age. The disease occurs in both males and females and does not seem to be influenced by whether or not the animal is spayed or neutered. It is not contagious to other pets in the household, including other ferrets.

Signs of DIM in Ferrets

The signs of DIM appear suddenly and can worsen rapidly. A ferret can behave perfectly normally one day and show severe signs of DIM the next. Signs are variable, but they commonly include a lack of energy and appetite, weight loss, nausea and vomiting, fever, depression, and/or weakness that can impair their ability to walk. Other signs commonly seen that are not specific to just DIM include excess mucus around their eyes and nose, increased heart rate breathing rate, and changes to the skin. Ferrets with DIM are often found lying down, are reluctant to move, and react painfully to touch, especially around their back.

Diagnostics

Diagnosing DIM can be challenging because the signs are commonly seen with many other diseases and we do not fully understand what causes it. There is no definitive diagnosis for DIM, which means there is no test to determine with 100% certainty whether or not your pet has this disease. If your ferret shows a combination of these signs, your veterinarian will most likely complete blood and urine tests, radiographs, and possibly an ultrasound to assess the severity of the disease progression and try to rule out other potential causes. DIM is a diagnosis of exclusion, which means your veterinarian will run many tests to rule out other potential causes before concluding that your pet has DIM.

The main tool used for diagnosing DIM is a muscle biopsy where a small piece of muscle will be removed while your pet is under sedation to look for signs of tissue inflammation or an infection. However, the small section of muscle removed may not represent the health of the entire muscle tissue, so a biopsy that is negative for inflammation does not guarantee that other muscles are not being affected by the disease.

Treatment and Prognosis

Treatment for this disease remains controversial. Previously, there was little we could offer ferrets with this disease and euthanasia was a common result as we could not relieve the intense pain ferrets exhibited. Some veterinarians recommend and report success with a treatment protocol that includes antibiotic therapy, analgesics (pain medications), cyclophosphamide (medication used to treat some immune disorders and cancers), prednisone (a steroid), and various supplemental therapies. The goal of this therapy is not to treat a specific disease but to suppress inflammation and decrease auto-immune activity. In some ferrets, this treatment not only prevents further progression of the disease but may hide signs of disease. This protocol is recommended by the American Ferret Association and continued research needs to be done to determine overall treatment effectiveness.

Supplemental Therapy

Supplemental therapies, which include supportive care, are recommended along with the anti-inflammatory and immune-modulating medications previously mentioned. These medications are tailored to your ferret’s needs and health status and are typically given to keep your ferret hydrated and to prevent weight loss. It is important to recognize that these medications alone will not relieve suffering nor lessen the effects of this disease on your ferret’s body and immune system.

Nutritional support includes hand feeding to encourage your ferret to eat more to prevent weight loss. Also, hand feeding makes swallowing easier and absorption of nutrients more likely. Sometimes warming up your ferret’s food (warm, not hot) can make it more enticing. Your veterinarian may also recommend a prescription diet.

Other supplemental therapies that are commonly recommended include intravenous or subcutaneous fluid administration, physical therapy, vitamins, and gastrointestinal protectants (medications to help prevent ulcers). Ferrets with DIM also need (and will appreciate) extra “TLC” or tender loving care, and gentle handling.

Prognosis (Outcome) Discussion

Ferrets with DIM that receive anti-inflammatory and immune-modulation treatment have a better prognosis than ferrets that receive just pain medication and supportive care. Still, not every patient may respond to treatment. Previously, many ferrets with suspected DIM were euthanized since this was considered untreatable and it was humane to end the ferret’s suffering. If the owners agreed to it, the ferret’s body underwent an autopsy to determine what was causing the disease, and muscle sections were examined looking for evidence of DIM.