Maggot therapy

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Maggot therapy
Maggot debridement therapy on a diabetic foot.jpg
Maggot debridement therapy on a wound from a diabetic foot
Other namesmaggot debridement therapy (MDT), larval therapy, larva therapy, larvae therapy, biodebridement, biosurgery

Maggot therapy (also known as larval therapy) is a type of biotherapy involving the introduction of live, disinfected maggots (fly larvae) into non-healing skin and soft-tissue wounds of a human or other animal for the purpose of cleaning out the necrotic (dead) tissue within a wound (debridement), and disinfection. There is evidence that maggot therapy may help with wound healing. [1] [2]

Contents

Medical uses

Maggots in medical packaging Larven der Lucillia sericata im BioBag.jpg
Maggots in medical packaging

Maggot therapy improves healing in chronic ulcers. [1] In diabetic foot ulcers there is tentative evidence of benefit. [3] A Cochrane review of methods for the debridement of venous leg ulcers found maggot therapy to be broadly as effective as most other methods, but the study also noted that the quality of data was poor. [4]

In 2003, the United States Food and Drug Administration (FDA) cleared maggots from common green bottle fly for use as a "medical device" in the US for the purpose of treatment of: [5]

Limitations

The wound must be of a type that can benefit from the application of maggot therapy. A moist, exudating wound with sufficient oxygen supply is a prerequisite. Not all wound-types are suitable: wounds which are dry, or open wounds of body cavities do not provide a good environment for maggots to feed. In some cases it may be possible to make a dry wound suitable for larval therapy by moistening it with saline soaks. [6]

Patients and doctors may find maggots distasteful, although studies have shown that this does not cause patients to refuse the offer of maggot therapy. [7] Maggots can be enclosed in opaque polymer bags to hide them from sight. Dressings must be designed to prevent any maggots from escaping, while allowing air to get to the maggots. [8] Dressings are also designed to minimize the uncomfortable tickling sensation that the maggots often cause. [9]

Mechanisms of action

The maggots have four principal actions:

Debridement

In maggot therapy, large numbers of small maggots consume necrotic tissue far more precisely than is possible in a normal surgical operation, and can debride a wound in a day or two. The area of a wound's surface is typically increased with the use of maggots due to the undebrided surface not revealing the actual underlying size of the wound. They derive nutrients through a process known as "extracorporeal digestion" by secreting a broad spectrum of proteolytic enzymes [13] that liquefy necrotic tissue, and absorb the semi-liquid result within a few days. In an optimum wound environment maggots molt twice, increasing in length from about 2 mm to about 10 mm, and in girth, within a period of 48–72 hours by ingesting necrotic tissue, leaving a clean wound free of necrotic tissue when they are removed. [14]

Disinfection

Secretions from maggots believed to have broad-spectrum antimicrobial activity include allantoin, urea, phenylacetic acid, phenylacetaldehyde, calcium carbonate, proteolytic enzymes, and many others. [15] In vitro studies have shown that maggots inhibit and destroy a wide range of pathogenic bacteria including methicillin-resistant Staphylococcus aureus (MRSA), group A and B streptococci, and Gram-positive aerobic and anaerobic strains. [16] Other bacteria like Pseudomonas aeruginosa , E. coli or Proteus spp. are not attacked by maggots, and in case of Pseudomonas even the maggots are in danger. [17]

Biology of maggots

Lucilia sericata, Green Bottle Fly Green bottle fly3.jpg
Lucilia sericata , Green Bottle Fly
Protophormia terraenovae, Northern blowfly Pterraenovae.jpg
Protophormia terraenovae , Northern blowfly

Those flies whose larvae feed on dead animals will sometimes lay their eggs on the dead parts (necrotic or gangrenous tissue) of living animals. The infestation by maggots of live animals is called myiasis. Some maggots will feed only on dead tissue, some only on live tissue, and some on live or dead tissue. The flies used most often for the purpose of maggot therapy are blow flies of the Calliphoridae: the blow fly species used most commonly is Lucilia sericata , the common green bottle fly. Another important species, Protophormia terraenovae , is also notable for its feeding secretions, which combat infection by Streptococcus pyogenes and S. pneumoniae . [18]

History

Written records have documented that maggots have been used since antiquity as a wound treatment. [19] There are reports of the use of maggots for wound healing by Maya, Native Americans, and Aboriginal tribes in Australia. Maggot treatment was reported in Renaissance times. Military physicians observed that soldiers whose wounds had become colonized with maggots experienced significantly less morbidity and mortality than soldiers whose wounds had not become colonized. These physicians included Napoleon's general surgeon, Baron Dominique Larrey. Larrey reported during the French campaign in Egypt and Syria (1798–1801) that certain species of fly consumed only dead tissue and helped wounds to heal. [18]

Joseph Jones, a ranking Confederate medical officer during the American Civil War, stated:

I have frequently seen neglected wounds ... filled with maggots ... as far as my experience extends, these worms eat only dead tissues, and do not injure specifically the well parts."

The first documented therapeutic use of maggots in the United States is credited to a second Confederate medical officer Dr. J.F. Zacharias, who reported during the American Civil War that:

"Maggots in a single day would clean a wound much better than any agents we had at our command ... I am sure I saved many lives by their use."

He recorded a high survival rate in patients he treated with maggots. [20]

During World War I, orthopedic surgeon William S. Baer recorded the case of a soldier left for several days on the battlefield who had sustained compound fractures of the femur and large flesh wounds. The soldier arrived at the hospital with maggots infesting his wounds but had no fever or other signs of infection and survived his injuries, which would normally have been fatal. After the war, Baer began using maggot therapy at Boston Children's Hospital in Massachusetts. [21] [22] : 169–71 

There were reports that American prisoners of war of the Japanese in World War II resorted to maggot therapy to treat severe wounds. [23] [24]

A survey of US Army doctors published in 2013 found that 10% of them had used maggot therapy. [25]

Regulation

In January 2004, the FDA granted permission to produce and market maggots for use in humans or animals as a prescription-only medical device for the following indications: "For debriding non-healing necrotic skin and soft tissue wounds, including pressure ulcers, venous stasis ulcers, neuropathic foot ulcers, and non-healing traumatic or post-surgical wounds." [26] [27]

Veterinary use

The use of maggots to clean dead tissue from animal wounds is part of folk medicine in many parts of the world. [28] It is particularly helpful with chronic osteomyelitis, chronic ulcers, and other pus-producing infections that are frequently caused by chafing due to work equipment.[ citation needed ] Maggot therapy for horses in the United States was re-introduced after a study published in 2003 by veterinarian Dr. Scott Morrison. This therapy is used in horses for conditions such as osteomyelitis secondary to laminitis, sub-solar abscesses leading to osteomyelitis, post-surgical treatment of street-nail procedure for puncture wounds infecting the navicular bursa, canker, non-healing ulcers on the frog, and post-surgical site cleaning for keratoma removal. [29]

However, there have not been many case studies done with maggot debridement therapy on animals, and as such it can be difficult to accurately assess how successful it is. [30]

Related Research Articles

<span class="mw-page-title-main">Necrosis</span> Unprogrammed cell death caused by external cell injury

Necrosis is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is often regarded as one of the founders of modern pathology. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated digestion of cell components. In contrast, apoptosis is a naturally occurring programmed and targeted cause of cellular death. While apoptosis often provides beneficial effects to the organism, necrosis is almost always detrimental and can be fatal.

<span class="mw-page-title-main">Gangrene</span> Type of tissue death by infection or lack of blood supply

Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the gangrene is caused by an infectious agent, it may present with a fever or sepsis.

<span class="mw-page-title-main">Ulcer (dermatology)</span> Type of cutaneous condition

An ulcer is a sore on the skin or a mucous membrane, accompanied by the disintegration of tissue. Ulcers can result in complete loss of the epidermis and often portions of the dermis and even subcutaneous fat. Ulcers are most common on the skin of the lower extremities and in the gastrointestinal tract. An ulcer that appears on the skin is often visible as an inflamed tissue with an area of reddened skin. A skin ulcer is often visible in the event of exposure to heat or cold, irritation, or a problem with blood circulation.

<span class="mw-page-title-main">Wound</span> Acute injury from laceration, puncture, blunt force, or compression

A wound is any disruption of or damage to living tissue, such as skin, mucous membranes, or organs. Wounds can either be the sudden result of direct trauma, or can develop slowly over time due to underlying disease processes such as diabetes mellitus, venous/arterial insufficiency, or immunologic disease. Wounds can vary greatly in their appearance depending on wound location, injury mechanism, depth of injury, timing of onset, and wound sterility, among other factors. Treatment strategies for wounds will vary based on the classification of the wound, therefore it is essential that wounds be thoroughly evaluated by a healthcare professional for proper management. In normal physiology, all wounds will undergo a series of steps collectively known as the wound healing process, which include hemostasis, inflammation, proliferation, and tissue remodeling. Age, tissue oxygenation, stress, underlying medical conditions, and certain medications are just a few of the many factors known to affect the rate of wound healing.

<span class="mw-page-title-main">Maggot</span> Larva of a fly

A maggot is the larva of a fly ; it is applied in particular to the larvae of Brachycera flies, such as houseflies, cheese flies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and crane flies.

<span class="mw-page-title-main">Debridement</span> Medical removal of dead, damaged, or infected tissue

Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue. Removal may be surgical, mechanical, chemical, autolytic (self-digestion), or by maggot therapy.

<span class="mw-page-title-main">Pressure ulcer</span> Skin damage resulting from long-term pressure

Pressure ulcers, also known as pressure sores, bed sores or pressure injuries, are localised damage to the skin and/or underlying tissue that usually occur over a bony prominence as a result of usually long-term pressure, or pressure in combination with shear or friction. The most common sites are the skin overlying the sacrum, coccyx, heels, and hips, though other sites can be affected, such as the elbows, knees, ankles, back of shoulders, or the back of the cranium.

<span class="mw-page-title-main">Myiasis</span> Infestation of parasitic maggots

Myiasis, also known as flystrike or fly strike, is the parasitic infestation of the body of a live animal by fly larvae (maggots) that grow inside the host while feeding on its tissue. Although flies are most commonly attracted to open wounds and urine- or feces-soaked fur, some species can create an infestation even on unbroken skin. Non-myiatic flies can be responsible for accidental myiasis.

<span class="mw-page-title-main">Common green bottle fly</span> Species of insect

The common green bottle fly is a blowfly found in most areas of the world and is the most well-known of the numerous green bottle fly species. Its body is 10–14 mm (0.39–0.55 in) in length – slightly larger than a house fly – and has brilliant, metallic, blue-green or golden coloration with black markings. It has short, sparse, black bristles (setae) and three cross-grooves on the thorax. The wings are clear with light brown veins, and the legs and antennae are black. The larvae of the fly may be used for maggot therapy, are commonly used in forensic entomology, and can be the cause of myiasis in livestock and pets. The common green bottle fly emerges in the spring for mating.

<span class="mw-page-title-main">Venous ulcer</span> Skin sore sustained by a vasculatory disease

Venous ulcer is defined by the American Venous Forum as "a full-thickness defect of skin, most frequently in the ankle region, that fails to heal spontaneously and is sustained by chronic venous disease, based on venous duplex ultrasound testing." Venous ulcers are wounds that are thought to occur due to improper functioning of venous valves, usually of the legs. They are an important cause of chronic wounds, affecting 1% of the population. Venous ulcers develop mostly along the medial distal leg, and can be painful with negative effects on quality of life.

A chronic wound is a wound that does not heal in an orderly set of stages and in a predictable amount of time the way most wounds do; wounds that do not heal within three months are often considered chronic. Chronic wounds seem to be detained in one or more of the phases of wound healing. For example, chronic wounds often remain in the inflammatory stage for too long. To overcome that stage and jump-start the healing process, a number of factors need to be addressed such as bacterial burden, necrotic tissue, and moisture balance of the whole wound. In acute wounds, there is a precise balance between production and degradation of molecules such as collagen; in chronic wounds this balance is lost and degradation plays too large a role.

The history of wound care spans from prehistory to modern medicine. Wounds naturally heal by themselves, but hunter-gatherers would have noticed several factors and certain herbal remedies would speed up or assist the process, especially if it was grievous. In ancient history, this was followed by the realisation of the necessity of hygiene and the halting of bleeding, where wound dressing techniques and surgery developed. Eventually the germ theory of disease also assisted in improving wound care.

<span class="mw-page-title-main">Negative-pressure wound therapy</span> Therapeutic technique

Negative-pressure wound therapy (NPWT), also known as a vacuum assisted closure (VAC), is a therapeutic technique using a suction pump, tubing, and a dressing to remove excess exudate and promote healing in acute or chronic wounds and second- and third-degree burns. The therapy involves the controlled application of sub-atmospheric pressure to the local wound environment using a sealed wound dressing connected to a vacuum pump. The use of this technique in wound management started in the 1990s and this technique is often recommended for treatment of a range of wounds including dehisced surgical wounds, closed surgical wounds, open abdominal wounds, open fractures, pressure injuries or pressure ulcers, diabetic foot ulcers, venous insufficiency ulcers, some types of skin grafts, burns, sternal wounds. It may also be considered after a clean surgery in a person who is obese.

<span class="mw-page-title-main">Calciphylaxis</span> Painful, necrotic skin lesions associated with chronic kidney disease

Calciphylaxis, also known as calcific uremic arteriolopathy (CUA) or “Grey Scale”, is a rare syndrome characterized by painful skin lesions. The pathogenesis of calciphylaxis is unclear but believed to involve calcification of the small blood vessels located within the fatty tissue and deeper layers of the skin, blood clots, and eventual death of skin cells due to lack of blood flow. It is seen mostly in people with end-stage kidney disease but can occur in the earlier stages of chronic kidney disease and rarely in people with normally functioning kidneys. Calciphylaxis is a rare but serious disease, believed to affect 1-4% of all dialysis patients. It results in chronic non-healing wounds and indicates poor prognosis, with typical life expectancy of less than one year.

<i>Lucilia illustris</i> Species of insect

Lucilia illustris is a member of the fly family Calliphoridae, commonly known as a blow fly. Along with several other species, L. illustris is commonly referred to as a green bottle fly. Lucilia illustris is typically 6–9 mm in length and has a metallic blue-green thorax. The larvae develop in three instars, each with unique developmental properties. The adult fly typically will feed on flowers, but the females need some sort of carrion protein in order to breed and lay eggs.

Lucilia thatuna belongs to the family Calliphoridae, the species most commonly referred to as the blowflies, and the genus Lucilia. Along with several other species of Lucilia, L. thatuna is commonly referred to as a green bottle fly. L. thatuna is very scarce and not much is known about this particular fly. It has been noted to reside in mountainous regions of the northwestern United States.

Proteases are in use, or have been proposed or tried, for a number of purposes related to medicine or surgery. Some preparations involving protease have undergone successful clinical trials and have regulatory authorization; and some further ones have shown apparently useful effects in experimental medical studies. Proteases have also been used by proponents of alternative therapies, or identified in materials of traditional or folk medicine. A serine protease of human origin, activated protein C, was produced in recombinant form and marketed as Drotrecogin alfa and licensed for intensive-care treatment of severe sepsis. It was voluntarily withdrawn by the manufacturer in 2011 after being shown to be ineffective.

<span class="mw-page-title-main">Diabetic foot ulcer</span> Medical condition

Diabetic foot ulcer is a breakdown of the skin and sometimes deeper tissues of the foot that leads to sore formation. It is thought to occur due to abnormal pressure or mechanical stress chronically applied to the foot, usually with concomitant predisposing conditions such as peripheral sensory neuropathy, peripheral motor neuropathy, autonomic neuropathy or peripheral arterial disease. It is a major complication of diabetes mellitus, and it is a type of diabetic foot disease. Secondary complications to the ulcer, such as infection of the skin or subcutaneous tissue, bone infection, gangrene or sepsis are possible, often leading to amputation.

<span class="mw-page-title-main">Insects in medicine</span> Uses of insects for medicinal purposes

Insects have long been used in medicine, both traditional and modern, sometimes with little evidence of their effectiveness.

<span class="mw-page-title-main">Diabetic foot infection</span> Medical condition

Diabetic foot infection is any infection of the foot in a diabetic person. The most frequent cause of hospitalization for diabetic patients is due to foot infections. Symptoms may include pus from a wound, redness, swelling, pain, warmth, tachycardia, or tachypnea. Complications can include infection of the bone, tissue death, amputation, or sepsis. They are common and occur equally frequently in males and females. Older people are more commonly affected.

References

  1. 1 2 Sun, Xinjuan; Jiang, Kechun; Chen, Jingan; et al. (2014). "A systematic review of maggot debridement therapy for chronically infected wounds and ulcers". International Journal of Infectious Diseases . 25: 32–7. doi: 10.1016/j.ijid.2014.03.1397 . PMID   24841930.
  2. ↑ Nasoori, A.; Hoomand, R. (December 2017). "Maggot debridement therapy for an electrical burn injury with instructions for the use of Lucilia sericata larvae". Journal of Wound Care . 26 (12): 734–41. doi:10.12968/jowc.2017.26.12.734. PMID   29244970.
  3. ↑ Tian, X; Liang, XM; Song, GM; et al. (September 2013). "Maggot debridement therapy for the treatment of diabetic foot ulcers: a meta-analysis". Journal of Wound Care . 22 (9): 462–9. doi:10.12968/jowc.2013.22.9.462. PMID   24005780.
  4. ↑ Gethin, Georgina; Cowman, Seamus; Kolbach, Dinanda N. (14 September 2015). "Debridement for venous leg ulcers". Cochrane Database of Systematic Reviews . 2015 (9): CD008599. doi: 10.1002/14651858.CD008599.pub2 . PMC   6486053 . PMID   26368002.
  5. ↑ "Product Classification: Maggots, Medical". fda.gov. US: Food and Drug Administration.
  6. ↑ Gottrup, Finn; Jørgensen, Bo (2011). "Maggot Debridement: An Alternative Method for Debridement". ePlasty. 11 (33). Copenhagen: 290–302. PMC   3136394 . PMID   21776326.
  7. ↑ Parnés, A.; Lagan, K. M. (2007). "Larval therapy in wound management: A review" (PDF). International Journal of Clinical Practice . 61 (3): 488–93. doi:10.1111/j.1742-1241.2006.01238.x. PMID   17313618. S2CID   34169406.
  8. ↑ Scavée, V; Polis, X; Schoevaerdts, J. C. (2003). "Maggot therapy: Many hands make light work" (PDF). Acta Chirurgica Belgica. 103 (4): 405–7. doi:10.1080/00015458.2003.11679453. PMID   14524161. S2CID   28650392. Archived from the original (PDF) on 2016-03-10. Retrieved 2015-03-04.
  9. ↑ Morgan, Rosemary (2002). "Larval therapy". Student BMJ. 10: 259–302. doi:10.1136/sbmj.0208271. S2CID   220099046.
  10. ↑ Chan, Dominic CW; Fong, Daniel HF; Leung, June YY; Patil, NG; Leung, Gilberto KK (October 2007). "Maggot debridement therapy in chronic wound care". Hong Kong Medical Journal. 13 (5): 382–6. PMID   17914145.
  11. 1 2 Sherman, R. A. (2014). "Mechanisms of Maggot-Induced Wound Healing: What Do We Know, and Where Do We Go from Here?". Evidence-Based Complementary and Alternative Medicine. 2014: 1–13. doi: 10.1155/2014/592419 . PMC   3976885 . PMID   24744812.
  12. ↑ Sherman, R. A. (2009). "Maggot Therapy Takes Us Back to the Future of Wound Care: New and Improved Maggot Therapy for the 21st Century". Journal of Diabetes Science and Technology. 3 (2): 336–44. doi:10.1177/193229680900300215. PMC   2771513 . PMID   20144365.
  13. ↑ Reames, Mark K.; Christensen, Chris; Luce, Edward A. (1988). "The Use of Maggots in Wound Debridement". Annals of Plastic Surgery. 21 (4): 388–91. doi:10.1097/00000637-198810000-00017. PMID   3232928.
  14. ↑ Jordan, Ashley; Khiyani, Neeraj; Bowers, Steven R.; Lukaszczyk, John J.; Stawicki, Stanislaw P. (2018). "Maggot debridement therapy: A practical review". International Journal of Academic Medicine . 4 (1): 21–34. doi: 10.4103/IJAM.IJAM_6_18 . S2CID   88155109.
  15. ↑ Heuer, Heike; Heuer, Lutz (2011). "Blowfly Strike and Maggot Therapy: From Parasitology to Medical Treatment". In Mehlhorn, Heinz (ed.). Nature Helps . Parasitology Research Monographs. pp.  301–23. ISBN   978-3-642-19381-1.
  16. ↑ Bowling, Frank L.; Salgami, Eleanna V.; Boulton, Andrew J.M. (February 2007). "Larval Therapy: A Novel Treatment in Eliminating Methicillin-Resistant Staphylococcus aureus From Diabetic Foot Ulcers". Diabetes Care. 30 (2): 370–371. doi: 10.2337/dc06-2348 . PMID   17259512.
  17. ↑ Andersen, A. S.; Joergensen, B.; Bjarnsholt, T.; Johansen, H.; Karlsmark, T.; Givskov, M.; Krogfelt, K. A. (2009). "Quorum-sensing-regulated virulence factors in Pseudomonas aeruginosa are toxic to Lucilia sericata maggots". Microbiology. 156 (2): 400–7. doi: 10.1099/mic.0.032730-0 . PMC   2885677 . PMID   19892758.
  18. 1 2 Sherman, R. A.; Hall, M. J. R.; Thomas, S. (2000). "Medicinal Maggots: An Ancient Remedy for Some Contemporary Afflictions". Annual Review of Entomology. 45: 55–81. doi:10.1146/annurev.ento.45.1.55. PMID   10761570.
  19. ↑ Whitaker, I. S.; Twine, C; Whitaker, M. J.; et al. (2007). "Larval therapy from antiquity to the present day: Mechanisms of action, clinical applications and future potential". Postgraduate Medical Journal . 83 (980): 409–13. doi:10.1136/pgmj.2006.055905. PMC   2600045 . PMID   17551073.
  20. ↑ Donnelly, J. (1998). "Wound healing--from poultices to maggots. (a short synopsis of wound healing throughout the ages)". The Ulster Medical Journal . 67 (Suppl 1): 47–51. PMC   2448900 . PMID   9807955.
  21. ↑ Baer, William S. (1931). "The treatment of chronic osteomyelitis with the maggot (larva of the blow fly)". The Journal of Bone and Joint Surgery . 13 (3): 438–75. Archived from the original on 2016-01-07. Retrieved 2015-03-03.
  22. ↑ Roach, Mary (2016-06-07). Grunt: The Curious Science of Humans at War (1 ed.). W. W. Norton & Company. ISBN   9780393245448.
  23. ↑ Nimmons, Don Stewart (2003). Treasures of War. Xulon Press. p. 105. ISBN   9781591604600.
  24. ↑ Congressional Record. Pt 6. Vol. 152. 8 May 2006. pp. 7, 908.
  25. ↑ Heitkamp, Rae A.; Peck, George W.; Kirkup, Benjamin C. (2013-11-14). "Maggot Debridement Therapy in Modern Army Medicine: Perceptions and Prevalence". Military Medicine . 177 (11): 1, 411–16. doi: 10.7205/milmed-d-12-00200 . PMID   23198524.
  26. ↑ Carrie Arnold for Scientific American. April 1, 2013 New Science Shows How Maggots Heal Wounds
  27. ↑ FDA CDRH 510(k) summary
  28. ↑ Root-Bernstein, Robert; Root-Bernstein, Michèle M. (1998). Honey, Mud, Maggots, and Other Medical Marvels. Houghton Mifflin. ISBN   978-0-395-92492-1.[ unreliable medical source? ][ page needed ]
  29. ↑ Sherman, Ronald A.; Morrison, Scott; Ng, David (2007). "Maggot debridement therapy for serious horse wounds – A survey of practitioners". The Veterinary Journal. 174 (1): 86–91. doi:10.1016/j.tvjl.2006.05.012. PMID   16831562.
  30. ↑ Jones, Gemma; Wall, Richard (2008). "Maggot-therapy in veterinary medicine". Research in Veterinary Science. 85 (2): 394–8. doi:10.1016/j.rvsc.2007.12.006. PMID   18237754.

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