Maggot versus conservative debridement therapy for the treatment of pressure ulcers

Certain fly larvae can infest corpses or the wounds of live hosts. Those which are least invasive on live hosts have been used therapeutically, to remove dead tissue from wounds, and promote healing. This medicinal use of maggots is increasing around the world, due to its efficacy, safety and simplicity. Given our low cultural esteem for maggots, the increasing use and popularity of maggot therapy is evidence of its utility. Maggot therapy has successfully treated many types of chronic wounds, but much clinical and basic research is needed still. In this review, the biology of myiasis and the history of maggot therapy are presented, the current status of our understanding and clinical use of medicinal maggots is discussed, and opportunities for future research and applications are proposed.

Fly maggots have been known for centuries to help debride and heal wounds. Maggot therapy was first introduced in the USA in 1931 and was routinely used there until the mid-1940s in over 300 hospitals. With the advent of antimicrobiols, maggot therapy became rare until the early 1990s, when it was re-introduced in the USA, UK, and Israel. The objective of this study was to assess the efficacy of maggot therapy for the treatment of intractable, chronic wounds and ulcers in long-term hospitalized patients in Israel. Twenty-five patients, suffering mostly from chronic leg ulcers and pressure sores in the lower sacral area, were treated in an open study using maggots of the green bottle fly, Phaenicia sericata. The wounds had been present for 1-90 months before maggot therapy was applied. Thirty-five wounds were located on the foot or calf of the patients, one on the thumb, while the pressure sores were on the lower back. Sterile maggots (50-1000) were administered to the wound two to five times weekly and replaced every 1-2 days. Hospitalized patients were treated in five departments of the Hadassah Hospital, two geriatric hospitals, and one outpatient clinic in Jerusalem. The underlying diseases or the causes of the development of wounds were venous stasis (12), paraplegia (5), hemiplegia (2), Birger's disease (1), lymphostasis (1), thalassemia (1), polycythemia (1), dementia (1), and basal cell carcinoma (1). Subjects were examined daily or every second day until complete debridement of the wound was noted. Complete debridement was achieved in 38 wounds (88.4%); in three wounds (7%), the debridement was significant, in one (2.3%) partial, and one wound (2.3%) remained unchanged. In five patients who were referred for amputation of the leg, the extremities was salvaged after maggot therapy. Maggot therapy is a relatively rapid and effective treatment, particularly in large necrotic wounds requiring debridement and resistant to conventional treatment and conservative surgical intervention.