Untitled Document

Venous Stasis/Diabetic Ulcers

A common complication of diabetes is impaired wound healing. Non-healing diabetic foot ulcers are the cause of 25-50% of all diabetic hospital admissions and most of the 60,000 to 70,000 amputations that are performed in the U.S. each year. The statistics are grim for diabetics: almost 15% of all diabetic patients will develop one or more foot ulcers and 15-25% of those will ultimately require amputation. Infection is reported to be the cause of amputation in 25% to 50% of diabetic patients with foot ulcers with minor amputations in 24% to 60% of the patients and major amputations in 10% to 40% range.

The World Health Organization and the International Diabetes Federation have set a target to reduce amputation rates by 50%, but little progress has been made. Maggot debridement therapy shows real promise in reducing the need for amputations.

Case 1
Sherman reports that 18 patients with 20 non-healing ulcers were evaluated. Six wounds were treated with conventional therapy, 6 with maggot therapy, and 8 with conventional therapy first and then maggot therapy. Maggot therapy was associated with faster debridement and healing than conventional therapy.

9 days: maggot treated wounds saw a 50% reduction in necrotic surface area and conventional therapy reached 50% after 29 days.
14 days: maggot-treated wounds were covered by only 7% necrotic tissue compared with 39% necrotic tissue for conventional therapy.
4 weeks: maggot treated wounds were 100% debrided, whereas wounds treated with conventional therapy for an average of 5 weeks had only a 66% reduction of necrotic tissue.

Maggot therapy was also associated with faster growth of granulation tissue and greater wound healing rates. Within 4 weeks, the maggot treated wounds were not only debrided, but over 55% of the wound base was covered with healthy granulation tissue. In contrast, wounds treated with conventional therapy had granulation tissue over only 15% of the wounds. Those wounds first treated with conventional therapy showed little improvement until maggot therapy was instituted. The study demonstrated that MDT was of significant benefit to chronic diabetic patients with pressure and venous stasis ulcers.

This is not to suggest that conventional therapy is ineffective. This study only evaluated wounds that were not responding to conventional treatment and found that maggot debridement therapy was far more effective in treating these chronic wounds. Sherman suggests that treatment with maggots should be 2nd or 3rd tier treatment rather than a last desperate attempt.

Case 2
Ruff and Stephens document the case of a 70 year old woman with Type-1 diabetes and generally poor health, who presented with a large infected ulcer on her left heel. Because of multiple health problems, she was considered a risk for surgical intervention. Initially, the wound measured 7.5 cm by 9 cm, covered 80% with black necrotic tissue and 20% yellow slough, so that the depth could not be measured. The wound was draining small amounts of green-yellow offensive discharge. Maggot debridement therapy was begun and steady improvement ensued. By the end of the second treatment, most of the black eschar was gone and the wound odor had abated. Slough and necrotic tissue support the proliferation of anaerobic bacteria, which result in wound odor. The maggots help to remove the wound odor by consuming the necrotic tissue and slough and decreasing the bacterial count.

Four more treatments were done and by that stage, the wound had been completely debrided and there was granulation tissue covering half of the wound. After these treatments, conventional therapy was resumed and within 12 weeks, the wound was fully-healed. The use of maggot debridement therapy had successfully avoided the need for amputation and promoted healing.

Case 3
Sherman also reports the progress of a 60-year-old man with diabetes and recurrent venous stasis resistant to conventional treatment and antibiotics.

Please click on the following link to view the stunning results Dr. Sherman has obtained with MDT.
http://www.ucihs.uci.edu/com/pathology/sherman/cases.htm

While most maggot debridement therapy treatments show very good response, Summers and Kaminski note that maggot debridement therapy may be ineffective in treating some diabetic wounds, particularly in patients who suffer from severe hypoperfusion. Also, wounds where the larvae may be crushed (such as those between the toes or the heel) may make maggot therapy less effective, unless patients are specifically instructed to avoid walking or other activities injurious to the maggots. In many cases, patients are maintained on bed rest during the treatment in order to protect the maggots. Despite some drawbacks, maggot therapy can be especially useful in patients suffering heart or lung disease, where surgery can present extra risks.

Instant feedback:

Maggots are less effective than surgical debridement for the treatment of venous stasis/diabetic ulcers.