IntroductionIntroduction

Chronic bacterial colonization or infection of ulcer is one of the major factors Chronic bacterial colonization or infection of ulcer is one of the major factors interfering proper wound healing, especially in diabetic foot ulcers. The interfering proper wound healing, especially in diabetic foot ulcers. The maggot therapy has been used for debridement of necrotic tissues, however, maggot therapy has been used for debridement of necrotic tissues, however, never been studied for potential antimicrobial propertiesnever been studied for potential antimicrobial properties..  Maggots clean up wounds beautifully - a fact known for centuries, especially to Maggots clean up wounds beautifully - a fact known for centuries, especially to military surgeons, who found that battle wounds accidentally infested with military surgeons, who found that battle wounds accidentally infested with maggots healed quickly without becoming infected. According to Dr. Ronald maggots healed quickly without becoming infected. According to Dr. Ronald Sherman (University of California, Irvine, CA, USA), maggot therapy was Sherman (University of California, Irvine, CA, USA), maggot therapy was introduced into civilian medicine in the USA in the 1930s but fell out of favor introduced into civilian medicine in the USA in the 1930s but fell out of favor with the introduction of antibiotics. But maggots are now making a comeback, with the introduction of antibiotics. But maggots are now making a comeback, especially in the treatment of chronic wounds infected with antibiotic-resistant especially in the treatment of chronic wounds infected with antibiotic-resistant bacteriabacteria..  Recently, Dr. Sherman presented the preliminary results of his prospective Recently, Dr. Sherman presented the preliminary results of his prospective trial of conventional wound care followed by maggot therapy at a Wound trial of conventional wound care followed by maggot therapy at a Wound Healing Society symposium in Toronto, Canada. 43 maggot-treated wounds Healing Society symposium in Toronto, Canada. 43 maggot-treated wounds were debrided faster and more completely than they had been during were debrided faster and more completely than they had been during conventional treatmentconventional treatment..  In a randomized trial in 12 patients with sloughy venous ulcers, Michael In a randomized trial in 12 patients with sloughy venous ulcers, Michael Walker (West Cumberland Hospital, Whitehaven, UK) found that maggot Walker (West Cumberland Hospital, Whitehaven, UK) found that maggot therapy debrided the ulcers more quickly and effectively than standard therapy debrided the ulcers more quickly and effectively than standard hydrogel dressings - all six patients treated with maggots had their ulcers hydrogel dressings - all six patients treated with maggots had their ulcers successfully debrided with a single application, whereas two of the six successfully debrided with a single application, whereas two of the six

hydrogel-treated patients still needed dressings a month laterhydrogel-treated patients still needed dressings a month later... .   Live maggots were clinically suggested to kill or inhibit the growth of a range of Live maggots were clinically suggested to kill or inhibit the growth of a range of pathogenic bacteria, especially Methicillin resistant Staphyloccocus Aureus pathogenic bacteria, especially Methicillin resistant Staphyloccocus Aureus (MRSA) and group A and B Streptococci. They show clinical activity against (MRSA) and group A and B Streptococci. They show clinical activity against Pseudomonas species, although no formal prospective experimental study Pseudomonas species, although no formal prospective experimental study was arranged in the past. The clinical findings are consistent with the was arranged in the past. The clinical findings are consistent with the observations that maggots can combat infections in a variety of wound types, observations that maggots can combat infections in a variety of wound types, including those infected with antibiotic-resistant strains. including those infected with antibiotic-resistant strains.   In fact the treatment of wounds infected with MRSA is likely to become a In fact the treatment of wounds infected with MRSA is likely to become a major indication for the use of maggot therapy in the future. The presence of major indication for the use of maggot therapy in the future. The presence of large amounts of necrotic tissue in wounds can prevent topical antibacterials, large amounts of necrotic tissue in wounds can prevent topical antibacterials, such as mupirocin, from reaching the site of infectionsuch as mupirocin, from reaching the site of infection..  The objective of this study is to assess the potential antimicrobial properties of The objective of this study is to assess the potential antimicrobial properties of maggots in vitromaggots in vitro..  Design: Prospective randomized experimental study. Design: Prospective randomized experimental study. Setting: Research microbiology laboratory.Setting: Research microbiology laboratory.

Methods

Application of live maggots, larvae of Lucilia (Phaenicia) sericata to total of 48 culture plates of Methicillin resistant Staphyloccocus Aureus (MRSA), Pseudomonas aeruginosa, Vancomycin resistant enteroccocus (VRE), and Candida Albicans (12 plates in each group). The maggots were covered by a small plate inside the big plate with the pathogen. All the plates were incubated in the standard incubator and examined 24 and 48 hours after application of maggots. Main outcome measuresDegree of lysis in bacterial or fungal cultures in the area of maggot application. Gram staining of both areas was performed.

Results Complete lysis of the bacterial or fungal cultures in the area of maggot application was observed 24 hours after application of live maggots in all culture plates and confirmed by Gram staining. This complete lysis was persistent for more than 5 days after the maggot application.

DiscussionHow the maggots combat wound infection is not entirely clear and several explanations have been suggested. Ammonia in maggot secretions may partly account for this antimicrobial effect by raising wound pH. Dr. Sherman proposed special antimicrobial agents in maggot secretion. One report suggested that phenylacetate and phenylacetataldehyde may exert antimicrobial effect. Direct ingestion of bacteria along with semiliquid food by the maggots and subsequent lysis in their gut is also possible explanation.

Conclusion: Complete lysis of the bacterial or fungal cultures in the area of maggot application provides convincing evidence for the antimicrobial properties of maggots. The exact mechanism of antimicrobial property of maggots requires further investigation.

References:References:  1: Jarvis A. 1: Jarvis A. Maggot therapy. Maggot therapy. Lancet. 2000 Dec 9;356(9246):2016.Lancet. 2000 Dec 9;356(9246):2016.    2. Wayman J, Nirojogi V, Walker A, Sowinski A, Walker MA..2. Wayman J, Nirojogi V, Walker A, Sowinski A, Walker MA..    The cost effectiveness of larval therapy in venous ulcers. J Tissue Viability. 2000 Jul;10(3):91-4. Erratum The cost effectiveness of larval therapy in venous ulcers. J Tissue Viability. 2000 Jul;10(3):91-4. Erratum in: J Tissue Viability 2001Jan;11(1):51.  in: J Tissue Viability 2001Jan;11(1):51.    3: Bonn D. 3: Bonn D.   Maggot therapy: an alternative for wound infection. Maggot therapy: an alternative for wound infection. Lancet. 2000 Sep 30;356(9236):1174. Lancet. 2000 Sep 30;356(9236):1174.

    4. Dissemond J, Koppermann M, Esser S, Schultewolter T, Goos M, Wagner SN4. Dissemond J, Koppermann M, Esser S, Schultewolter T, Goos M, Wagner SN. .

  Treatment of methicillin-resistant Staphylococcus aureus (MRSA) as part of biosurgical Treatment of methicillin-resistant Staphylococcus aureus (MRSA) as part of biosurgical management of a chronic leg ulcermanagement of a chronic leg ulcer..  Hautarzt 2002 Sep;53(9):608-1Hautarzt 2002 Sep;53(9):608-1         

Assessment of Antimicrobial Properties Of MaggotsAssessment of Antimicrobial Properties Of Maggots

Leon Margolin M.D., Ph.D. (1) ; Philip Gialanella MSc (2)

1. UPMC 2. AECOM

A

DC

Complete lysis of the cultures 24h after maggot application:A - Pseudomonas Aeruginosa; B - Methicillin Resistant Staphylococcus Aureus (MRSA)

C - Candida Albicans, D - Vancomycin Resistant Enterococcus (VRE)

B