Presurgical maggot debridement of soft tissue wounds is associated with decreased rates of postoperative infection

Lucillia Sericata larval therapy in the treatment of diabetic chronic wounds

Purpose

Wounds with dead tissue, purulent wounds, and gangrene are good options for larval therapy. We aim to investigate the effect of larval therapy on diabetic wounds and compare it with traditional treatment.

Methods

The sterile larvae were used in wound treatment and the infection rate, Erythrocyte Sedimentation Rate (ESR), and wound size were measured and compared before and after the treatment.

Results

The scars of 40 patients in the larval therapy group were evaluated every 10 days and the mean size of the scar decreased from 38.5 cm (36.6 cm) before treatment to 5.0 cm (6.6 cm) after 60 days. ESR mean was decreased from 57.3 (18.3) before treatment to 15.8 (4.8) after treatment in the larval therapy group. These parameters were significantly decreased compared to the debridement group (p < 0.001).

Conclusions

Larval therapy is effective in diabetic wound healing. The size of the wound after larval treatment is smaller than before. There was no difference between the two groups for infection rate. ESR was significantly decreased in the larval therapy group that indicating the lower inflammation in this group.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-00973-w.

The effect of Lucilia sericata larval excretion/secretion (ES) products on cellular responses in wound healing

Chronic wounds are still regarded as a serious public health concern, which are on the increase mainly due to the changes in life styles and aging of the human population. There are different types of chronic wounds, each of which requires slightly different treatment strategies. Nevertheless, wound bed preparation is included in treatment of all types of chronic wounds and involves tissue debridement, inflammation, and infection control, as well as moisture balance and epithelial edge advancement. Maggot therapy (MT) is a form of biological debridement which involves the application of live medical grade Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae) larvae. Whereas it was initially thought to act mainly through debridement, today MT is known to influence all four overlapping physiological phases of wound repair: homeostasis, inflammation, proliferation, and remodelling/maturing. During MT, medical-grade larvae are applied either freely or enclosed in tea-bag like devices (biobag) inside the wounds, which suggests that larva excretion/secretion (ES) products can facilitate the healing processes directly without the need of direct contact with the larvae. This review summarizes the relevant literature on ES-mediated effects on the cellular responses involved in wound healing.

Maggot Therapy as a Part of a Holistic Approach in the Treatment of Multimorbid Patients with Chronic Ulcer

Patients with chronic wounds (leg ulcers, decubitus, and diabetic foot ulcers) suffer from marked restrictions in their quality of life and can often no longer adequately carry out their everyday tasks. The need for nursing and medical care increases when other illnesses and complaints are present at the same time. Qualified wound care and the treatment of comorbidities are therefore of particular importance. The treatment of this disease, which is increasing in number, requires a holistic, multimodal treatment approach which, in addition to professional wound care, also includes comorbidities in the treatment. This case study describes an old treatment method for refractory wounds, the so-called "maggot therapy", and shows how this is integrated into a holistic, multimodal therapeutic approach.

Efficacy of maggot debridement therapy on refractory leg ulcers of Behçet disease: an open-label study

BACKGROUND

Cutaneous ulcers of Behçet disease (BD) are rare but have high morbidity and resistance to conventional therapies. An important and essential aspect of ulcer management is debridement. Regarding maggot therapy (MT), excretions of the green bottle fly, Lucilia sericata, have been shown to have the ability to remove necrotic debris and promote healing.

AIM

To evaluate the efficacy of MT for cutaneous ulcers of BD.

METHODS

In this open-label trial, patients with BD with refractory leg ulcers suitable for MT were enrolled. Maggot application was performed until complete debridement was achieved, and all patients were followed up for 12 months afterwards to assess the total healing of ulcers.

RESULTS

In total, 24 patients with 32 ulcers were enrolled. Using MT, 91.6% of all ulcers were completely debrided. Mean time to debridement was 14.9 days and mean number of cycles required was 5.3. Mean ulcer size was decreased by 23% with treatment. Time to debridement was positively correlated with pretreatment ulcer size and ulcer duration (P = 0.01 and P < 0.01) but not with ulcer depth, comorbidities, smoking, age or sex (P > 0.05 for all). During follow-up, 79.1% of all ulcers healed completely. Mean time required for total healing was positively correlated with ulcer duration, pretreatment and post-treatment ulcer area, ulcer depth and mean time to total debridement (P < 0.03, P = 0.00, P = 0.04 and P < 0.01, respectively).

CONCLUSIONS

To our knowledge, the findings presented in this first and unique study may provide key answers about factors affecting success rate of MT in BD cutaneous ulcers.

Clinical study of Maggot therapy for Fournier's gangrene

Fournier's Gangrene is a fulminating necrotizing fasciitis of the perineum and genitalia. Standard treatment involves immediate excision of all necrotic tissue, aggressive antibiotic coverage, and supportive medical care. Still, the infection is commonly fatal or disfiguring. Wound treatment with disinfected blowfly larvae (maggot debridement therapy or MDT) has been shown to be highly effective, with multiple studies demonstrating effective debridement, disinfection, and promotion of granulation tissue. MDT also has been associated with preservation of viable tissue and minimised blood loss. This report describes a prospective clinical study of MDT for Fournier's gangrene aimed to test the hypothesis that early use of maggots could decrease the number of surgical treatments required to treat Fournier's gangrene. Subjects were provided with one initial surgical excision, followed by debridement using only medical grade Lucilia sericata larvae. Only two subjects were enrolled, both diabetic men. Intensive care and culture-directed antimicrobial coverage were administered as usual. Maggot debridement was associated with the disappearance of necrotic tissue, control of infection and granulation tissue growth. In both subjects, wounds healed without requiring further surgical resection or anatomical reconstruction. Maggot therapy decreased the number of surgical procedures that otherwise would have been necessary, and led to favourable outcomes.

Effectiveness of Chronic Wound Debridement with the Use of Larvae of Lucilia Sericata

The process of successful wound healing depends on effective debridement and infection control. One method of wound debridement, known since antiquity, is based on the use of fly larvae. Solid scientific evidence proves that maggot debridement therapy (MDT), like surgical intervention, can be effectively and safely used to remove necrotic tissue. Based on a review of the related literature, this study was designed to assess the effectiveness of chronic wound cleansing with the use of larvae of Lucilia sericata (Phaenicia sericata). Maggot therapy, applied in wound debridement and treatment, is a safe and effective method. Its benefits are associated with debridement, disinfection and faster tissue growth. MDT may reduce the duration of antibiotic therapy and the need for hospitalization, or it may decrease the number of outpatient visits required. It is a relatively cost-effective method, and, in addition to financial gains, it may reduce the frequency of inpatient treatment. In the literature, an increasing amount of scientific evidence confirms that such treatment can effectively reduce the biofilm and bacterial load in a wound.

Evaluating Sarconesiopsis magellanica blowfly-derived larval therapy and comparing it to Lucilia sericata-derived therapy in an animal model

Larval therapy is used as alternative treatment for hard-to-heal chronic and infected wounds. Lucilia sericata is the most used blowfly species. However, it has been shown recently that Sarconesiopsis magellanica larval excretions and secretions have potent antibacterial activity; this blowfly belongs to the Calliphoridae family. The present work has dealt with evaluating larval therapy using S. magellanica on wounds induced in diabetic rabbits and its action was compared to the effect induced by L. sericata. Twelve New Zealand White rabbits (Oryctolagus cuniculus) were used; they were divided into 4 groups, the first two being treated with larval therapy derived from both aforementioned necrophagous blowflies, an antibiotic was used in the third and the fourth was used as control. All the animals were wounded on the back and infected with Pseudomonas aeruginosa and Staphylococcus aureus. Samples of the secretion from each animal's infected wound were taken and sown on blood agar. The colony forming units were then counted. The PUSH scale was used for the macroscopic evaluation of the wounds. Bacterial control was encountered 48 h post-treatment in the treatments involving larval therapy and to a lesser extent with the antibiotic. Likewise, wound debridement was quicker and more efficient with larval therapy compared to the antibiotic group; however, wound closing time was 23 days in all treatments. The group treated with S. magellanica larvae had relatively quicker evolution until the proliferation phase and the start of maturation, even though there were no significant differences between both blowfly species evaluated here regarding treatments by the end of the treatment period. The present study has validated the diabetic rabbit model for inducing chronic wounds regarding larval therapy and has likewise confirmed the effectiveness of S. magellanica-derived larval therapy as an alternative for curing and healing wounds.

The effects of Sarconesiopsis magellanica larvae (Diptera: Calliphoridae) excretions and secretions on fibroblasts

Sarconesiopsis magellanica is a necrophagous blowfly which is relevant in both forensic and medical sciences. Previous studies regarding this species have led to understanding life-cycle, population and reproduction parameters, as well as identifying and characterising proteolytic enzymes derived from larval excretions and secretions (ES). As other studies have shown that ES proteolytic activity plays a significant role in wound healing and fibroblasts play a relevant role in granulation tissue formation during such healing, the present study was aimed at analysing the biological effect of S. magellanica larval ES on fibroblasts. ES were obtained from third-instar larvae and added to fibroblast cells at three concentrations (10, 5 and 1 μg/mL) to evaluate their behaviour. MTT assays were used for analysing cell proliferation and viability, whilst cell adhesion was measured by optical density with 10% SDS. Fibroblast migration and morphology was recorded by microscopic observation. ES did not affect fibroblast viability and induced an increase in cell proliferation; cell adhesion became reduced, whilst cell migration through extracellular matrix increased. ES also induced a decreased cell surface and morphological alterations. Changes in all the above-mentioned parameters were reduced when ES were incubated at 60 °C, probably due to protease denaturation. These results suggested that the proteases contained in S. magellanica larval ES contributed towards granulation tissue formation, increased cell migration and promoted cell proliferation. All these data support carrying out further experiments aimed at validating S. magellanica usefulness in larval therapy.

Helminthes and insects: maladies or therapies

By definition, parasites cause harm to their hosts. But, considerable evidence from ancient traditional medicine has supported the theory of using parasites and their products in treating many diseases. Maggots have been used successfully to treat chronic, long-standing, infected wounds which failed to respond to conventional treatment by many beneficial effects on the wound including debridement, disinfection, and healing enhancement. Maggots are also applied in forensic medicine to estimate time between the death and discovery of a corpse and in entomotoxicology involving the potential use of insects as alternative samples for detecting drugs and toxins in death investigations. Leeches are segmented invertebrates, famous by their blood-feeding habits and used in phlebotomy to treat various ailments since ancient times. Leech therapy is experiencing resurgence nowadays in health care principally in plastic and reconstructive surgery. Earthworms provide a source of medicinally useful products with potential antimicrobial, antiviral, and anticancer properties. Lumbrokinases are a group of fibrinolytic enzymes isolated and purified from earthworms capable of degrading plasminogen-rich and plasminogen-free fibrin and so can be used to treat various conditions associated with thrombotic diseases. Helminth infection has been proved to have therapeutic effects in both animal and human clinical trials with promising evidence in treating many allergic diseases and can block the induction of or reduce the severity of some autoimmune disorders as Crohn's disease or ulcerative colitis. What is more, venomous arthropods such as scorpions, bees, wasps, spiders, ants, centipedes, snail, beetles, and caterpillars. The venoms and toxins from these arthropods provide a promising source of natural bioactive compounds which can be employed in the development of new drugs to treat diseases as cancer. The possibility of using these active molecules in biotechnological processes can make these venoms and toxins a valuable and promising source of natural bioactive compounds. The therapeutic use of helminthes and insects will be of great value in biomedicine and further studies on insect toxins will contribute extensively to the development of Biomedical Sciences.

Maggot debridement therapy: a systematic review

Maggot debridement therapy is used extensively in the UK in both community and hospital situations, but remains a potentially under-used modality in many wound care markets. It promotes wound healing by performing three key processes: debridement, disinfection and growth-promoting activity. It can be used for the debridement of non-healing necrotic skin and soft tissue wounds, including pressure ulcers, venous stasis ulcers, neuropathic foot ulcers and non-healing traumatic of post-surgical wounds. With the increase in chronic diabetic foot wounds, maggot debridement therapy is a promising tool for health professionals dealing with difficult wounds. This article presents an overview of the research evidence surrounding maggot debridement therapy that serves as a guide to health professionals who may be users of this form of treatment now and in the future.

Mechanisms of maggot-induced wound healing: what do we know, and where do we go from here?

MEDICINAL MAGGOTS ARE BELIEVED TO HAVE THREE MAJOR MECHANISMS OF ACTION ON WOUNDS, BROUGHT ABOUT CHEMICALLY AND THROUGH PHYSICAL CONTACT: debridement (cleaning of debris), disinfection, and hastened wound healing. Until recently, most of the evidence for these claims was anecdotal; but the past 25 years have seen an increase in the use and study of maggot therapy. Controlled clinical studies are now available, along with laboratory investigations that examine the interaction of maggot and host on a cellular and molecular level. This review was undertaken to extract the salient data, make sense, where possible, of seemingly conflicting evidence, and reexamine our paradigm for maggot-induced wound healing. Clinical and laboratory data strongly support claims of effective and efficient debridement. Clinical evidence for hastened wound healing is meager, but laboratory studies and some small, replicated clinical studies strongly suggest that maggots do promote tissue growth and wound healing, though it is likely only during and shortly after the period when they are present on the wound. The best way to evaluate-and indeed realize-maggot-induced wound healing may be to use medicinal maggots as a "maintenance debridement" modality, applying them beyond the point of gross debridement.

Proteolytic activity regarding Sarconesiopsis magellanica (Diptera: Calliphoridae) larval excretions and secretions

Sarconesiopsis magellanica (Diptera: Calliphoridae) is a medically important necrophagous fly which is used for establishing the post-mortem interval. Diptera maggots release proteolytic enzymes contained in larval excretion and secretion (ES) products playing a key role in digestion. Special interest in proteolytic enzymes has also been aroused regarding understanding their role in wound healing since they degrade necrotic tissue during larval therapy. This study was thus aimed at identifying and characterising S. magellanica proteolytic enzyme ES products for the first time. These products were obtained from first-, second- and third-instar larvae taken from a previously-established colony. ES proteins were separated by SDS-PAGE and their proteolytic activity was characterised by zymograms and inhibition assays involving BAPNA (Nα-benzoyl-dl-Arg-p-nitroanilide) and SAPNA substrates, using synthetic inhibitors. The protein profile ranged from ∼69kDa to ∼23kDa; several of them coincided with the Lucilia sericata ES protein profile. Serine-protease hydrolysis activity (measured by zymogram) was confirmed when a ∼25kDa band disappeared upon ES incubation with PMSF inhibitor at pH 7.8. Analysis of larval ES proteolytic activity on BAPNA and SAPNA substrates (determined by using TLCK and TPCK specific inhibitors) suggested a greater amount of trypsin-like protease. These results support the need for further experiments aimed at validating S. magellanica use in larval therapy.

Maggot therapy in wound management in modern era and a review of published literature

Maggot therapy is an old remedy, which is being looked into with renewed interest. The use of medicinal maggots was approved by Food and Drug Administration (FDA) as a medical device in 2004. Maggot therapy appears to be efficacious, well tolerated, and cost-effective. Because American Medical Association (AMA) and Centers for Medicare and Medicaid (CMS) released reimbursement coding guidelines with regards to maggot therapy, there is a potential for a wider use of maggot therapy in United States in the near future. Several mechanisms of action suggested for maggots in debriding wounds are discussed. While maggot therapy demonstrated effectiveness in necrotic wounds, not all wound types respond well to maggot therapy. Future large, randomized, well-designed studies would help better delineate the place of maggot therapy among other options for wound care, and determine whether maggot therapy should be initiated earlier in the course of treatment, or continued to be used as a last resort.

The efficacy of maggot debridement therapy--a review of comparative clinical trials

Over the last decade, maggot debridement therapy (MDT) has been recognized by many clinicians as a potential adjunct to conventional therapy, and many patients with non healing, chronic ulcers have been treated. Numerous case reports and case series have described the successful use of MDT in a variety of ulcers. However, comparative clinical trials and in particular randomized controlled trials investigating the efficacy of MDT are sparse. A systematic search in the literature showed three randomized clinical trials and five non randomized studies evaluating the efficacy of sterile Lucilia sericata applied on ulcers with various aetiologies. Of these, seven studies had debridement and/or healing as an outcome variable. When evaluating maggots as debriding agents, the studies report MDT as being significantly more effective than hydrogel or a mixture of conventional therapy modalities, including hydrocolloid, hydrogel and saline moistened gauze. However, the design of the studies was suboptimal, with important differences in the use of other therapies, such as compression, that may influence both debridement and healing between the compared groups, as well as inappropriately short follow-up times. The quality of the studies therefore makes it difficult to conclude that MDT shortens healing time. The poor quality of the data used for evaluating the efficacy of MDT highlights the need for more and better designed investigations.

Maggot debridement therapy for postsurgical wound infection in scoliosis: a case series in five patients

STUDY DESIGN

Case series of 5 patients who developed resistant wound infection after scoliosis surgery.

OBJECTIVE

To present maggot debridement therapy (MDT) as an effective alternative to the conventional treatment in postsurgical infection in scoliosis.

SUMMARY OF BACKGROUND DATA

Numerous clinical reports have been published that describe outstanding effects of MDT, most notable on debridement, cleansing, disinfection, and healing of indolent wounds, many of which have previously failed to respond to conventional treatment. However, till date no reports have been found in the literature describing its use for the treatment of wound infection after scoliosis surgery, which has relatively longer and deeper wound.

METHODS

A total of 5 patients (2 females and 3 males) who developed wound infection after scoliosis correction surgery were included in this study. All were operated for neuromuscular scoliosis using posterior approach with pedicle screw fixation. All developed deep wound infection within 2 to 6 weeks of surgery, which was resistant to all kinds of conventional therapy. MDT applied in all using prepared commercially available maggot bags, and dressing was changed twice a week till wound shows signs of healing. After confirming negative culture, MDT was stopped and routine dressings or secondary closure was done. During the treatment, wound appearance, size, and development of healing were observed.

RESULTS

There were 1 patient with paralytic scoliosis and 4 with cerebral palsy. All wound healed completely within 5.2 ± 1.8 weeks of MDT or 8.8 ± 3.8 cycles of MDT. There was no recurrence on final follow-up of 21.6 ± 5.9 months. Wound size was also decreased from 24.2 ± 3.3 cm of pre-MDT to 11.8 ± 4.5 cm post-MDT showing 51.2% reduction in wound size. There was partial implant removal in 2 cases before MDT; however, no further implant extraction was needed in any case after MDT. Treatment was tolerated well by all patients without any obvious complications due to MDT.

CONCLUSION

We would propose to use MDT for the treatment of wound infection after scoliosis surgery as an effective alternative to conventional treatment. In this way, implant extraction could be avoided without losing any correction.

Maggot therapy takes us back to the future of wound care: new and improved maggot therapy for the 21st century

In the 21st century, eighty years after William Baer presented his groundbreaking work treating bone and soft tissue infections with live maggots, thousands of therapists around the globe have rediscovered the benefits of maggot therapy. The renaissance in maggot therapy is due in large part to recent technological advancements that have solved or minimized many of the treatment's earlier drawbacks: the need for reliable access to this perishable medical device, simplified application, and low-cost production. Modern dressing materials have simplified the procedure and minimized the risk of escaping maggots. The establishment of dozens of laboratories throughout the world, along with access to overnight courier services in many regions, has made medicinal maggots readily available to millions of people in need. Studies show that fears of patient nonacceptance are unfounded. The medical literature is rapidly growing with scientific evidence demonstrating the efficacy and safety of maggot therapy for a variety of problematic wounds. This article examines how these and other technologies are optimizing the study and application of maggot therapy for wound care.

Clinical and microbiological efficacy of MDT in the treatment of diabetic foot ulcers

OBJECTIVE

To assess the clinical and microbiological efficacy of maggot debridement therapy (MDT) in the management of diabetic foot ulcers unresponsive to conventional treatment and surgical intervention.

METHOD

Consecutive diabetic patients with foot wounds presenting at the vascular surgery unit and the diabetic foot unit of Alexandria Main University Hospital were selected for MDT. Lucilia sericata medicinal maggots were applied to the ulcers for three days per week. Changes in the percentage of necrotic tissue and ulcer surface area were recorded each week over the 12-week follow-up period. Semiquantitative swab technique was used to determine the bacterial load before and after MDT.

RESULTS

The sample comprised 10 patients with 13 diabetic foot ulcers. The mean baseline ulcer surface area was 23.5cm2 (range 1.3-63.1), and the mean percentage of necrotic tissue was 74.9% (range 29.9-100). Complete debridement was achieved in all ulcers in a mean of 1.9 weeks (range 1-4). Five ulcers (38.5%) were completely debrided with one three-day MDT cycle. The mean reduction in ulcer size was significant at 90.2%, and this occurred in a mean of 8.1 weeks (range 2-12). The mean weekly reduction in ulcer size was 16.1% (range 8.3-50). Full wound healing occurred in 11 ulcers (84.6%) within a mean of 7.3 weeks (range 2-10). The bacterial load of all ulcers reduced sharply after the first MDT cycle to below the 10(5) threshold, which facilitates healing.

CONCLUSION

The results highlight the potential benefits of MDT in diabetic wound care in developing countries. MDT was proved to be a rapid, simple and efficient method of treating these ulcers.

Topical and Systemic Medications for Wounds

There are a plethora of topical and systemic medications available to the veterinary practitioner today that aid the wound healing process. Some of these help to maintain a moist environment. Others increase growth factors, provide local energy sources, control infection, provide for debridement, increase wound blood flow and temperature, or reduce wound edema. Modern wound care requires that the proper products(s)be used, depending on the condition of the wound and the phase of wound healing. This article discusses various wound care products and provides guidelines on their use.

Maggot Therapy: The Science and Implication for CAM Part I-History and Bacterial Resistance

It is now a universally acknowledged fact that maggot therapy can be used successfully to treat chronic, long-standing, infected wounds, which have previously failed to respond to conventional treatment. Such wounds are typically characterized by the presence of necrotic tissue, underlying infection and poor healing. Maggot therapy employs the use of freshly emerged, sterile larvae of the common green-bottle fly, Phaenicia (Lucilia) sericata, and is a form of artificially induced myiasis in a controlled clinical situation. In this review article, we will discuss the role of maggots and their preparation for clinical use. Maggot therapy has the following three core beneficial effects on a wound: debridement, disinfection and enhanced healing. In part I we explore our current understanding of the mechanisms underlying these effects.