Thank you for contacting us with your question! My name is Dr. Kristi Rhodes and I am a veterinarian at North Bay Animal Hospital. My interest is primarily in exotic animal medicine because I love rats as well, so I can certainly appreciate your concern about your sweet pet! Regarding bumblefoot, severe footpad infections are common among small mammals housed on improper substrate, especially cages with wire flooring.
In some cases, substandard hygiene, including fecal soiling, can make the problem bigger. Symptoms of this condition include swelling of the affected feet, lameness, and reluctance to move. Improved sanitation and better substrate are the initial steps in correcting the problem. In addition, the feet themselves should be evaluated by a veterinarian. In many cases, either topical or oral medications to treat the infections are needed along with these husbandry changes. Pain relief is also often recommended as these lesions can be very painful.
Other possible causes for the clinical signs you are seeing include other types of infection, neoplasia, or other abnormalities that should also be assessed by a veterinarian.
Abscesses in any species can be notoriously difficult to treat and can often cause further complications such as life threatening bony infections without proper veterinary care, so we welcome you to make an appointment with us at any time so that we can perform a full physical exam and discuss any additional recommendations such as medications or husbandry changes that may help your pet to feel better as soon as possible.