Sept. 22, 2011 (Chicago) -- Maggots helped to heal the wounds of people with diabetes after multiple traditional treatments had failed, a small study shows.
Leg and foot sores in 27 of 37 people with diabetes healed after treatment with medical maggots. The wounds had been open for several months to five years.
Medical-grade maggots basically chew away dead flesh, leaving live tissue unscathed, says researcher Lawrence Eron, MD, of the University of Hawaii. They also appear to disinfect the wound and stimulate healing.
Maggots don't completely close wounds. "But there's 50% or more closure," he says.
"These little critters may allow [patients] to heal and avoid amputation or at least delay it so they can live the rest of their lives with their limbs intact," he tells WebMD.
As the saying goes, a picture is worth a thousand words. At the Interscience Conference on Antimicrobial Agents and Chemotherapy here, Eron flashed before-and-after photos showing a gangrenous foot ulcer healing after so-called maggot debridement therapy.
The doctors wanted to amputate the leg before the treatment, Eron says.
Maggots Have Long Medical History
Maggots havebeen used in medicine for thousands of years. Duringthe Napoleonic wars, surgeons observed that wounds infested with maggots tended to heal better than others.
Medical maggot use declined with the advent of antibiotics. Now, with antibiotic-resistant infections skyrocketing, they're making a comeback.
The new study involved people with diabetes who had failed multiple treatments. About 50 to 100 maggots were placed in a mesh that resembles panty hose and applied to their wounds.
They were removed after two days, at which time the maggots appeared plump from the feeding frenzy.
New maggots were then reapplied, and the cycle was repeated for an average of about five times.
Eron admits there is a "yuck" factor. Five patients experienced discomfort, which was treated successfully with acetaminophen. One patient stopped treatment due to pain.
Other patients described a "creepy, crawling sensation," Eron says. But they welcomed it as they previously had no feelings at all in the area of their wounds.
Eron isn't sure exactly how maggots achieve their medical magic. "What we saw, and suspected, is an [antibacterial] effect," he says.
Maggots also seem to excrete substances that boost the body's immune system and stimulate the growth of new blood vessels, he says.
More study is needed, Eron says.
Cost of Treatment
About 25.8 million children and adults in the U.S. -- 8.3% of the population -- have diabetes, according to the American Diabetes Association. In 2006, about 65,700 lower-limb amputations were performed in people with diabetes.
Medical-grade maggots are fly larvae grown in a hygienic lab so they are germ-free, says Catherine Bennett, PhD, head of the School of Health and Social Development at the Deakin University Australia in Burwood, Australia. She moderated the session at which the findings were presented.
"It's obviously quite a process," she says.
For the study, Eron used larvae of the green bottle fly, purchased from Monarch Labs for about $100 for a two-day cycle. Total treatment cost on average for five cycles: $500.
In contrast, it costs up to $10,000 to treat an uninfected foot ulcer in a person with diabetes; up to $50,000 if amputation is needed, Eron says.
In addition to cost, the main advantage of maggot therapy is it "gets us around the problem of antibiotic resistance," Bennett tells WebMD.
While the treatment appeared safe and effective in this small study, larger, well-designed trials are needed to convince patients as well as doctors, she says.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.