Common name: Bumblefoot
Definition
The inflammation an infection of the plantar surface and connective tissue of the foot/feet.
Clinical Signs
May observe any of the following:
Raised reddened tissue on the sole of one or both hind feet
Open sore or ulceration on the sole of one or both hind feet
Intermittent bleeding
Presence of pus if abscessed.
Etiology
Ulcerative pododermatitis is a chronic granulomatous condition resulting from ulcerative lesions, and necrosis of the tissue on the plantar or heel portion of the feet.
The lesions, often resulting from abraded tissue or pressure, begin as a small, reddish, raised area of keratinized growth that develops crusts/scabs. Intermittent bleeding results when these areas filled with blood break open, drain, and then close. If the area is abscessed, then along with the blood, pus fills the area and drains upon rupture. This cycle is repeated when continuous pressure is placed on these raised filled areas of tissue.
Secondary bacterial and fungal infections often develop when the abraded or ulcerated areas on the feet are exposed to normal skin flora, soiled bedding, or cages with accumulated urine soaked feces. If the wounds are left untreated, or if treatment is not effective, infection can spread to the lymphatic system, the bone causing osteomyelitis or travel to the blood causing bacteremia and sepsis. If there is secondary infection, Staphylococcus aureus is the bacteria most often cultured; however, other pathogens can be involved.
Factors that may play a part in the development of ulcerative pododermatitis are: rats that are overweight placing continued or excessive pressure on the feet, trauma, or minute abrasions from rough or irregular cage flooring, or rats having a genetic predisposition. It is also thought that the use of pine or cedar shavings used to cover cage floorings may play a part.
Although ulcerations of this sort, if caught early, can be cured the treatment may require weeks to months of diligent care. It is also important to try to determine the underlying reason and correct, or the condition is likely to return.
In those conditions where conservative treatment is unsuccessful, or where there is tissue necrosis, abscess development, or persistent bleeding, surgical debridement or amputation of the foot may be required. For those cases the prognosis is guarded.
Overall it is by far easier to try and prevent ulcerative pododermatitis than to affect a cure.
Photo examples of ulcerative pododermatitis:
- Fig. 1: Ulcerative pododermatitis of both feet.
- Fig. 2: Case histories and photo of ulcerative pododermatitis.
- Fig. 3 Ulcerative Pododermatitis case history and Blu-Kote application.
- Fig. 4 Ulcerative Pododermatitis: Snowy’s case history and photos.
Diagnostics
Assess for ulceration, bleeding, necrosis and infection.
Obtain a history for causative factors.
Culture and Sensitivity.
Treatment
Recommended treatment includes: cleaning lesions with an antiseptic solution, the application of a topical antibiotic ointment, as well as including an oral broad-spectrum antibiotic.
The following are various treatment options
Clean ulcerations using an antiseptic soap and water, or a 1% dilute solution of chlorhexaderm/chlorhexidine flush. Apply Blu-Kote spray (wound medication for horses found in feed stores) to wound area at least two times a day, or more if the feet become soiled . An alternative to Blu-Kote is Granulex spray.
Clean ulcerations using an antiseptic soap and water, or a 1% dilute solution of chlorhexaderm/chlorhexidine flush. Apply Zymox (ear cleanser) otic solution to ulcerative areas, with or without hydrocortisone, depending on inflammation present. Give broad-spectrum antibiotic, Clavamox (amoxicillin-clavulanate), orally.
Cleaning the ulceration with a betadine solution (dilute to color of weak tea), and then applying a betadine ointment at least three times a day.
The cleaning of the ulceration and application of Neosporin topical antibiotic ointment, along with Blu-Kote application if bumbles are persistent.
Cleaning ulceration with antiseptic solution and apply DILUTED tea tree oil to the bumbles several times each day.
(Note: tea tree oil contains phenol-containing essential oil. Active ingredients are cyclic terpenes which are similar in structure and action to turpentine . There have been reports of toxicity after consuming tea tree oil by mouth. There has also been reports that when applied to the skin, tea tree oil can be mildly irritating resulting in the development of allergic contact dermatitis. If choosing to use this agent be sure to adequately dilute the tea tree oil, and do not let the rat lick the area.)
Cleaning the ulceration with antiseptic solution and apply diluted Grapefruit Seed Extract (found in Health Food Stores) to the ulceration several times a day. (recommended by Virginia Simpson, RMCA member)
Alternative Meds:Give Grapefruit Seed Extract (GSE) orally.
Use 1 drop per 10 pound of rat. Mix as 1 drop GSE for 9 drops fruit juice per dropper in a dropper bottle so each drop of juice contains 1/10th of a drop of GSE. Give 1 to 2 drops on a piece of bread twice daily. Store in refrigerator.
Refer to Nutriteam:Pets and Grapefruit Extract for more information and ordering.
Treatment and the healing of bumbles may take up to several weeks, or be persistent throughout the life of the rat. What is important here is that the treatment chosen, if showing signs of effectiveness, should be continued until the ulceration is healed. If signs indicate that the ulceration is not improving over time, or in the event there are signs of further infection both locally or systemically, the treatment needs to be reevaluated and changed.
In any case a veterinarian should be consulted, especially if condition worsens or fails to resolve with any prescribed treatment.
The following oral medications may be prescribed by the vet. Dosages can be obtained by reviewing the Rat Medication Guide:
- Trimethoprim-Sulfa
- Enrofloxacin
-
Clavamox
-
Flagyl (where anaerobic bacterial infections is suspected or confirmed)
-
Ketoconazole (where fungal infection is suspected or confirmed)
Debridement may be required in severe cases of ulceration where necrotic tissue or abscess is present, in order for healing to occur in viable tissue. However this can often be difficult due to the fact that rats normally do not have a lot of tissue on the foot to work with.
*Note: In cases that are very severe where surgery is required there is the risk that the rat will require amputation of the foot.(See article BumbleFoot by Mary Ann Isaksen, RMCA Founder )
Medication that may be used for pain control when surgical intervention is required:
- For severe pain or first 24 hours post-op: butorphanol (Torbugesic).
- For mild to moderate pain: Banamine (flunixin meglumine) or carprofen.
Nursing Care
Use chlorhexiderm, or chlorhexadine, at a concentration of not greater than 1%. Diluted solution should appear lighter than a robin’s egg blue.
When applying Blu-kote, allow time for the application to dry as much as possible ( or as rat allows ). This ointment does tend to be messy and will stain.
Maintain cleansing treatment and ointment applications until ulcerations are healed.
If antibiotics are given remember to include Benebac or yogurt with live active cultures in order to prevent normal gut flora from being destroyed by the antibiotics.
During treatment, provide clean bedding daily such as cloths or ink-free paper towels. Avoid litter-type bedding during treatment to prevent contamination or infection if wounds are present , and to prevent the litter from sticking to medicated areas of the foot or feet.
Monitor for extent of bleeding in order to prevent anemia.
Maintain healthy diet and reduce percentage of fat intake. Reduce number of treats if rat is overweight.
If no progress in healing is seen after several weeks, or if rat shows signs of further ulceration, abscess, foul smelling pus, or general apathy, contact
veterinarian.
Outcomes
Ulcerations heal.
Ulcerations do not develop into septic condition.
Healthy weight is obtained.
Prevention
Do a head to toe physical assessment of your rat weekly paying attention to the soles of feet. Clean and treat any cuts or abrasions found to prevent infection.
Maintain clean cage environment.
Cover wire floor cages. Examples of coverings can include vinyl floor covering, plastic needlepoint canvas, carpeting, towels, self stick tiles, plastic placemats, fiberboard, and plexiglass.
Use of litter boxes will help to prevent continued walking on either rough or soiled litter.
References
In vitro Antimicrobial Activity Assessment of Zymox Otic Solution Against a Broad Range of Microbial Organisms
Rajvinder Atwal, PhD
http://www.jarvm.com/articles/Vol1Iss3/Atwal.htm
Posted on June 29, 2003, 10:18,
Last updated on June 26, 2008, 21:42
| Integumentary / Skin
