Maggot versus conservative debridement therapy for the treatment of pressure ulcers

Maggot therapy for resistant infections: the disconnect between scientific evidence, clinical acceptance and practice

OBJECTIVE

Practitioners and scientists are re-examining marginalised wound care therapies to find strategies that combat the growing problem of antimicrobial resistance (AMR) without compromising patient outcomes. Maggot therapy (MT) makes up just an estimated 0.02% of UK's National Health Service spending on wound care. This study aims to uncover why MT is not used more often, despite its affordability and high level of efficacy for both debridement and disinfection, particularly in the context of AMR infections, and to determine what can be done to ensure MT is more effectively used in the future to improve patient outcomes and manage the growing problem of AMR.

METHOD

For this investigation, a qualitative review of case studies using MT against AMR infections and a quantitative analysis of randomised control trials (RCTs) were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework.

RESULTS

Analysis showed that MT is highly effective against a range of infections and wound types, and compares well against conventional therapies. The low use of MT may be due in part to the documented 'yuck factor', often associated with maggots as well as misconceptions around the cost, efficacy and accessibility of MT. To overcome these factors, more RCTs on the spectrum and efficacy of MT across various clinical manifestations are needed, as well as professional and public engagement campaigns.

CONCLUSION

MT is an underused therapy, particularly regarding AMR infections, and expanding its use in these circumstances appears warranted. MT could play a vital role in conserving the efficacy of the existing pool of antimicrobials available and should be considered in the development of antimicrobial stewardship programmes.

DECLARATION OF INTEREST

This work was supported by the Swansea Employability Academy, Swansea University (internal funding). The authors have no conflicts of interest to declare.

Larval Wound Therapy: Possibilities and Potential Limitations-A Literature Review

Patient-centered care (PCC) is recognized as a standard in healthcare for determining high quality. Honoring patients' values, experiences, needs, and preferences in devising, coordinating, and delivering care underscores the enhancement of the therapeutic rapport between patients and healthcare providers. Wound treatment involves a multi-stage process encompassing diagnostics and local wound dressing, which reduces the risk of infection through a coordinated interdisciplinary team. Within this team, nurses undertake specific professional functions and roles. The implementation of local therapy using innovative and scientifically substantiated methods may be hindered by a deficit of knowledge or inappropriate knowledge among staff and patients themselves. This study presents the challenges concerning the care of patients with chronic wounds treated using Lucilia sericata larvae, based on a review of the current scientific literature. A critical analysis of the literature spanning from 2002 to 2022 was conducted using the Medline, PubMed, Cochrane, and Termedia databases, employing keywords such as "maggot debridement therapy" in relation to acceptance and perception. As a result of the preliminary selection, 472 papers were identified, of which 12 publications were included in the development of this concept. The acquired data were organized and presented in the concluding section in the form of tables, accompanied by descriptions and references to individual studies. Negative psychological and somatic sensations were among the most prominent challenges among patients treated with Maggot Debridement Therapy (MDT). Pain related to peripheral ischemia or infection in this group of patients requires pain prophylaxis, including hyperalgesia and allodynia, in order to improve method tolerance. On the other hand, augmenting patients' understanding of MDT diminishes negative emotions, reinforces positive behaviors, and mitigates anxiety levels. MDT constitutes an effective and safe method. Its widespread use for chronic wounds requires substantial knowledge among healthcare professionals and patient education, along with that of their caregivers, to develop a positive attitude.

Defensins of Lucilia sericata Larvae and Their Influence on Wound Repair Processes in Practical Assessment-A Study of Three Cases

Bacteria inhabiting chronic wounds form a biofilm that prolongs and slows down the healing process. Increasingly common antibiotic resistance requires clinicians to search for effective and alternative treatment methods. Defensins are the most common antimicrobial peptides capable of eradicating pathogens. Their discovery in maggot secretions allowed for a broader understanding of the healing mechanisms, and approving the use of Lucilia sericata fly larvae in the treatment of infected wounds resulted in an effective and safe procedure. The aim of the study was to present the possibility of biofilm elimination in a chronic wound by means of medical maggots (Lucilia sericata) with the example of three selected clinical cases. The observation included three women who met the inclusion criterion of having venous insufficiency ulcers with inhibited regeneration processes. Medical maggots were applied in a biobag for three days, and observation was conducted for 21 consecutive days. In 2 cases, a significant elimination of necrotic tissue from the wound bed with local granulation tissue was observed 72 h after application of a larvae colony on the wounds. In 1 case, the application of the larvae accelerated the repair process by reducing the wound area by approximately 40% at the time of observation. The formation of biofilm in a chronic wound is one of the main causes of disturbances in its effective healing. Combining procedures (scraping, antiseptic compresses, MDT, NPWT) related to wound debridement increases the effectiveness of biofilm elimination. The use of medical maggots is a safe and effective method of choice, and it enhances the processes of debridement. However, confirmed indisputable data on their effectiveness and frequency of use in the process of stimulating healing processes are still not available in the literature.

Maggot Treatment of Necrotic Toe Developed After Traumatic Subtotal Amputation

Maggot debridement therapy (MDT) has been used for years in the treatment of chronic wounds and necrotic tissues. We report a case of subtotally amputated third toe that was treated with MDT after reattachment and developing complete necrosis. The necrotic toe was replaced with viable tissue and the wound healed completely after 2 weeks of MDT application. This case points out the regenerative effects of MDT besides its mechanical debridement effect on the necrotic tissue.

Larval Therapy and Larval Excretions/Secretions: A Potential Treatment for Biofilm in Chronic Wounds? A Systematic Review

Chronic wounds present a global healthcare challenge and are increasing in prevalence, with bacterial biofilms being the primary roadblock to healing in most cases. A systematic review of the to-date knowledge on larval therapy's interaction with chronic-wound biofilm is presented here. The findings detail how larval therapy-the controlled application of necrophagous blowfly larvae-acts on biofilms produced by chronic-wound-relevant bacteria through their principle pharmacological mode of action: the secretion and excretion of biologically active substances into the wound bed. A total of 12 inclusion-criteria-meeting publications were identified following the application of a PRISMA-guided methodology for a systematic review. The findings of these publications were qualitatively analyzed to provide a summary of the prevailing understanding of larval therapy's effects on bacterial biofilm. A further review assessed the quality of the existing evidence to identify knowledge gaps and suggest ways these may be bridged. In summary, larval therapy has a seemingly unarguable ability to inhibit and degrade bacterial biofilms associated with impaired wound healing. However, further research is needed to clarify and standardize the methodological approach in this area of investigation. Such research may lead to the clinical application of larval therapy or derivative treatments for the management of chronic-wound biofilms and improve patient healing outcomes at a time when alternative therapies are desperately needed.

Therapeutic effects of Lucilia sericata larval excretion/secretion products on Leishmania major under in vitro and in vivo conditions

Background

Leishmaniasis is a neglected infectious disease caused by protozoa of the genus Leishmania. The disease generally manifests as characteristic skin lesions which require lengthy treatment with antimonial drugs that are often associated with adverse side effects. Therefore, a number of studies have focused on natural compounds as promising drugs for its treatment. This study aimed to evaluate the effects of larval excretion/secretion products (ES) of Lucilia sericata in crude and fractionated forms on Leishmania major, by using in vitro and in vivo models.

Methods

The in vitro experiments involved evaluation of ES on both promastigotes and macrophage-engulfed amastigotes, whereas the in vivo experiments included comparative treatments of skin lesions in L. major-infected mice with Eucerin-formulated ES and Glucantime.

Results

The half maximal inhibitory concentrations of the crude ES, > 10-kDa ES fraction, < 10-kDa ES fraction, and Glucantime were 38.7 μg/ml, 47.6 μg/ml, 63.3 μg/ml, and 29.1 μg/ml, respectively. Significant differences were observed between percentage viabilities of promastigotes treated with the crude ES and its fractions compared with the negative control (P < 0.0001). The crude ES was more effective on amastigotes than the two ES fractions at 300 μg/ml. The macroscopic measurements revealed that the reduction of lesion size in mice treated with the crude ES followed quicker cascades of healing than that of mice treated with Glucantime and the ES fractions.

Conclusions

The present study showed that the larval ES of L. sericata in both crude and fractionated forms are effective for both intracellular and extracellular forms of L. major. Also, the ES exert both topical and systemic effects on mice experimentally infected with L. major.

Graphical abstract

Comparison of Larval Therapy and Vacuum-Assisted Closure Therapy after Revascularization in Peripheral Artery Disease Patients with Ischemic Wounds

Objective

Even for very successful peripheral revascularization therapy, treatment is not complete until the ulcerative, gangrenous, and infected wound is closed. This study was performed and compared the outcomes of vacuum-assisted closure (VAC) and maggot debridement therapy (MDT) following peripheral revascularization to accelerate the wound healing process.

Methods

We did a prospective randomized clinical trial between January 1, 2014, and June 21, 2019. This study included 72 patients (63 males and nine females). Balloon angioplasty was performed in 21 patients (29.2%), peripheral bypass in 39 (54.2%), and both balloon angioplasty and revascularization (hybrid) surgery in 12 (16.7%). Thirty-three patients (45.8%) received 15 VAC therapy sessions for a month. Therapy progress was monitored at 48 h intervals, and wound debridement was performed. Thirty-nine patients (54.2%) received an average of six larval therapy sessions for a month. Groups were compared with the X² test, and a statistically significant difference was found (P < 0.001).

Results

In the VAC therapy group (n = 33), 14 patients (42.4%) had their feet amputated, 5 (15.1%) had a toe amputated, and 4 (12.1%) had all of their toes amputated. A skin graft was performed on four patients (12.1%) who developed granulation tissue. The wounds of six patients (18.2%) undergoing VAC therapy healed. In the larval therapy group (n = 39), the wounds healed in 36 patients (92.3%), and 3 (7.7%) had a toe amputated.

Conclusion

Larval therapy was shown to be more effective than VAC therapy for the treatment of postrevascularization ischemic wounds. Thus, larval therapy can be used as an effective biological treatment method when major amputation is not required.

Maggot debridement therapy to treat hard-to-heal diabetic foot ulcers: a single-centre study

OBJECTIVE

Maggot debridement therapy (MDT) has seen a resurgence in recent years in the treatment of hard-to-heal wounds, as a result of rising antibiotic resistance. The sterilised larvae of Lucilia cuprina have been used in MDT in Malaysia since 2003, with encouraging results for the treatment of hard-to-heal diabetic wounds. We report a case series of 30 patients selected from our clinic by convenient sampling with diabetic lower limb ulcers treated with MDT. The average age of patients receiving MDT was >50 years. Of the 30 patients in the study, nine were female and 21 were male. All patients had underlying diabetes, two patients had leg ulcers and 28 patients had diabetic foot ulcers. Sterilised Lucilia cuprina larvae were applied via a standard method of 10 maggots per square centimetre and dressed with sterile gauze. The study endpoint was defined as ≤5% coverage with slough or necrotic tissue following three successive applications of MDT. In this study, maximum debridement of wounds was achieved in 96.6% (29 patients) of our patients, with ≤5% coverage with slough or necrotic tissue, in addition to a reduction in wound-related pain, as assessed by a visual analogue scale. No adverse events were reported. The findings of this study support the use of MDT as a safe, efficacious, and cost-effective method of managing diabetic wounds.

A molecular approach to maggot debridement therapy with Lucilia sericata and its excretions/secretions in wound healing

Chronic wounds caused by underlying physiological causes such as diabetic wounds, pressure ulcers, venous leg ulcers and infected wounds affect a significant portion of the population. In order to treat chronic wounds, a strong debridement, removal of necrotic tissue, elimination of infection and stimulation of granulation tissue are required. Maggot debridement therapy (MDT), which is an alternative treatment method based on history, has been used quite widely. MDT is an efficient, simple, cost-effective and reliable biosurgery method using mostly larvae of Lucilia sericata fly species. Larvae can both physically remove necrotic tissue from the wound site and stimulate wound healing by activating molecular processes in the wound area through the enzymes they secrete. The larvae can stimulate wound healing by activating molecular processes in the wound area through enzymes in their excretions/secretions (ES). Studies have shown that ES has antibacterial, antifungal, anti-inflammatory, angiogenic, proliferative, hemostatic and tissue-regenerating effects both in vivo and in vitro. It is suggested that these effects stimulate wound healing and accelerate wound healing by initiating a direct signal cascade with cells in the wound area. However, the enzymes and peptides in ES are mostly still undefined. Examining the molecular content of ES and the biological effects of these ingredients is quite important to illuminate the molecular mechanism underlying MDT. More importantly, ES has the potential to have positive effects on wound healing and to be used more as a therapeutic agent in the future, so it can be applied as an alternative to MDT 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.

Non-surgical treatment for pressure ulcer

Pressure, friction, shear force, and micromoisture can cause pressure ulcer. With the increase of the elderly population in Korea, the number of decubitus pressure ulcer patients is increasing due to worsening medical conditions by aging. In the case of quadriplegic and hemiplegic patients, there is considerable interest in the prevention and self-treatment of pressure ulcer following daily life recovery through rehabilitation. It is important to recognize that pressure ulcer can sometimes be avoided and can sometimes occur inevitably, and that preventive measures should be put in place. For the improvement of pressure ulcer, the patient’s systemic condition and the understanding of indications for local treatment should be improved. Recently, guidelines for dressing formulations related to exudate absorption capacity were introduced. For the successful treatment of pressure ulcer, adequate support of nutrition, control of stiffness, prevention of bacterial bioburden, removal of dead tissue (debridement), moisturizing of the skin, and selection of appropriate dressing materials should be applied comprehensively for individual patients.

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.

Prevention and treatment of pressure sore following spinal cord injury

Pressure sores or pressure injury is a serious complication of a spinal cord injury (SCI), representing a challenging problem for patients, their caregivers, and their physicians. Persons with SCI are vulnerable to pressure sores throughout their life. Pressure sores can potentially interfere with the physical, psychosocial, and overall quality of life. Outcomes directly depend on education and prevention along with conservative and surgical management. Therefore, it is very important to understand everything about pressure sores following SCI. This review covers epidemiology, cost, pathophysiology, risk factors, staging, evaluation tools, prevention, education, conservative wound care methods, surgical treatment, and future trends in wound healing related to post-SCI pressure sores. A change in nomenclature was adopted by the National Pressure Ulcer Advisory Panel in 2016, replacing “pressure ulcer”with “pressure injury.” New concepts of pressure injury staging, such as suspected deep tissue injuries and unstageable pressure injuries, were also introduced. A systematic evidence-based review of the prevention of and therapeutic interventions for pressure sores was also discussed.

Maggot Therapy in Wound Healing: A Systematic Review

BACKGROUND

It is estimated that 2% of the population in developing countries suffer from a chronic wound, making it a hidden phenomenon that is increasing as populations age. The ease of access to maggot therapy has made it increasingly attractive for implementation. This study aimed to explore the effectiveness of maggot therapy as compared to hydrogel dressings in the healing of chronic wounds.

METHODS

An electronic literature search until October 2019 was performed using Medline, Embase, and Cumulative Index of Nursing and Allied Health Literature. The eligibility criteria were chronic wound patients with an intervention that involved a comparison of any maggot species with hydrogel dressings.

RESULTS

The full text of five studies, involving 580 patients with chronic wounds, was retrieved. Four studies used the Lucilia sericata species. The maggot therapy facilitated faster and more effective debridement of non-viable tissue. It enabled faster development of granulation tissue and increased reduction in the wound surface area compared to hydrogel dressings. Maggot therapy had no effect on disinfection or complete healing rate for the wound.

CONCLUSION

Maggot therapy should be considered for faster wound debridement, granulation tissue development, and wound surface area reduction as well as in surgical contraindications. This review can be used as a guide to assist clinicians in identifying patients who may benefit from maggot therapy.

Wound Myiasis in Severe Venous Stasis Ulcer

Although myiasis infestation of wounds presents with significant psychological discomfort to patients, studies have shown that it can be beneficial in the management of recalcitrant ulcers resistant to standard management. Here we report a patient with persistent ulcers unresponsive to standard management who was lost to follow-up for five months and presented with ''maggots in his wound''. This however proved beneficial to the patient as the ulcer showed healthy granulation tissue on presentation and improved healing on follow-up. Our case presents the beneficial effect of myiasis infestation in the 21st century and helps to highlight a time-tested therapy with further encouragement of the use of biotherapy (sterile maggots) for the management of recalcitrant ulcers.

A Survey on Inhibitory Effect of Whole-Body Extraction and Secretions of Lucilia sericata's Larvae on Leishmania major In vitro

Background:

Leishmaniasis is a skin disease caused by Leishmania parasite. Despite being self-limiting, must be treated. Available drugs have side effects and drug resistance has also been seen.

Materials and Methods:

Maggot debridement therapy (MDT) is using sterile fly larvae (maggots) of blow flies (Lucilia sericata) for the treatment of different types of tissue wounds. Larvae have excreted and secreted substances that have been proved to have antimicrobial effects, in addition to the some other specifications.

Results:

In this study, the anti-leishmanial effects of extracts and secretions of sterile second- and third-instar larvae of L. sericata on the growth of Leishmania major promastigotes and amastigotes in the J774 macrophages have been evaluated in vitro.

Conclusion:

The results showed that extracts and secretions had almost the same leishmaniocidal effect on promastigotes and intracellular amastigotes without cytotoxic effect on macrophages.

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.

Beyond skin deep: Managing pressure injuries

Pressure injuries (previously called pressure ulcers) are a common finding among patients in acute, long-term, or home settings. Numerous pathophysiologic and risk mechanisms factor into the development of pressure injuries. The timely recognition of these injuries is imperative. Many treatments exist for pressure injuries but the focus of patient management should be on preventing injury-related complications.

Advanced drug delivery systems and artificial skin grafts for skin wound healing

Cutaneous injuries, especially chronic wounds, burns, and skin wound infection, require painstakingly long-term treatment with an immense financial burden to healthcare systems worldwide. However, clinical management of chronic wounds remains unsatisfactory in many cases. Various strategies including growth factor and gene delivery as well as cell therapy have been used to enhance the healing of non-healing wounds. Drug delivery systems across the nano, micro, and macroscales can extend half-life, improve bioavailability, optimize pharmacokinetics, and decrease dosing frequency of drugs and genes. Replacement of the damaged skin tissue with substitutes comprising cell-laden scaffold can also restore the barrier and regulatory functions of skin at the wound site. This review covers comprehensively the advanced treatment strategies to improve the quality of wound healing.

Maggot Therapy in Angiopathic Leg Ulcers: A Systematic Review and Meta-Analysis

Maggot therapy (MT) is a biological debridement tool using blowfly larvae to digest necrotic tissue as its food. In addition, maggot secretion contains several peptides that has antibacterial effect and healing stimulants that might enhance wound healing. Clinical outcomes from previous meta-analyses demonstrated benefit of MT, but results were highly heterogeneous. We have conducted an updated systematic review and meta-analysis with clearly defined clinical outcomes according to mechanism of MT including successful debridement, healing rate, and time to heal. Furthermore, our study was the first meta-analysis that reported wound-related pain between MT and conventional therapy. MEDLINE and Scopus were searched for comparative studies of MT and conventional therapy. Ten studies were eligible, of which 5 studies were angiopathic (venous or mixed arteriovenous ulcers) and the other 5 were diabetic foot ulcer. The MT had significant higher rate of successful debridement with risk ratio of 2.3 (95% confidence interval = 1.7-3.0) with low heterogeneity. Time to heal was about 3.1 weeks (95% confidence interval = 1.2-5.0), significantly shorter in MT but with high heterogeneity. Healing rate and pain were not significantly different between groups with high heterogeneity. In conclusion, MT was an effective debridement tool compared with conventional therapy. More studies should be done to confirm other findings because of high heterogeneity.

[Research progress of chronic wound debridement]

Objective

To review the research progress of chronic wound debridement.

Methods

The recent related literature concerning the mechanisms, advantages, limitations, and indications of the technologies of chronic wound debridement was extensively consulted, reviewed, and summarized.

Results

Debridement is essential for chronic wound healing, which includes autolytic debridement, enzymatic debridement, biodebridement, mechanical debridement, sharp/surgical debridement, ultrasound debridement, hydrosurgery debridement, and coblation debridement. Each technique has its own advantages and disadvantages.

Conclusion

There are many types of technologies of chronic wound debridement, which can be chosen according to clinical conditions. It is showed there are more significant advantages associated with the technique of coblation debridement relatively, which also has greater potential. Further study is needed to improve its efficacy.

Pathophysiologic Mechanisms and Current Treatments for Cutaneous Sequelae of Burn Wounds

Burn injuries are a pervasive clinical problem. Extensive thermal trauma can be life-threatening or result in long-lasting complications, generating a significant impact on quality of life for patients as well as a cost burden to the healthcare system. The importance of addressing global or systemic issues such as resuscitation and management of inhalation injuries is not disputed but is beyond the scope of this review, which focuses on cutaneous pathophysiologic mechanisms for current treatments, both in the acute and long-term settings. Pathophysiological mechanisms of burn progression and wound healing are mediated by highly complex cascades of cellular and biochemical events, which become dysregulated in slow-healing wounds such as burns. Burns can result in fibroproliferative scarring, skin contractures, or chronic wounds that take weeks or months to heal. Burn injuries are highly individualized owing to wound-specific differences such as burn depth and surface area, in addition to patient-specific factors including genetics, immune competency, and age. Other extrinsic complications such as microbial infection can complicate wound healing, resulting in prolonged inflammation and delayed re-epithelialization. Although mortality is decreasing with advancements in burn care, morbidity from postburn deformities continues to be a challenge. Optimizing specialized acute care and late burn outcome intervention on a patient-by-patient basis is critical for successful management of burn wounds and the associated pathological scar outcome. Understanding the fundamentals of integument physiology and the cellular processes involved in wound healing is essential for designing effective treatment strategies for burn wound care as well as development of future therapies. Published 2018. Compr Physiol 8:371-405, 2018.

Treatment of pressure ulcers with larvae of Lucilia sericata

Objectives

This study aims to investigate the use of the Lucilia sericata larvae in patients with decubitus ulcers resistant to hyperbaric oxygen treatment, vacuum-assisted closure, surgical debridement, and other conventional therapies.

Patients and methods

A total of 36 patients (21 females, 15 males; mean age 63.7 years; range 16 to 90 years) who were admitted to our hospital for decubitus ulcers between February 2011 and July 2016 were included in our study. All patients had one or more lesions in the sacral region, trochanteric area, dorsal region, or on the heel of the foot. Nine patients had spinal cord injuries, six of them were injured during a car accident, and three of them had spinal cord injuries due to gunshot. One patient had concomitant lung cancer, one had heart failure, and two patients had a diagnosis of multiple sclerosis. Thirty three of 36 patients were admitted to the wound therapy unit within the department of emergency medicine, and three were admitted to the physical therapy and rehabilitation clinic. For each patient, Lucilia sericata maggots were applied on the lesions for 72 hours and, then, washed away. This procedure was repeated two times a week. Twenty nine patients (78.9%) had four to six sessions and seven patients (21.1%) had eight to 12 sessions.

Results

Twenty nine lesions (78.9%) were Grade 2 and 3 and were completely healed after four to eight treatment sessions, while seven lesions (21.1%) were completely cured at the end of 10 to 14 sessions. There was complete clearance of necrotic debris at the end of two sessions within the first week for 15 lesions, whereas 10 lesions (27.8%) were cured after four sessions within two weeks, seven lesions (19.4%) within five sessions after three weeks, and four lesions (11.1%) were treated at the end of seven sessions for four weeks. All the necrotic crusts over the surface of the ulcers were cleaned and bad odor of the lesions disappeared.

Conclusion

Lucilia sericata larvae debridement is a rapid and effective treatment option for the management of chronic decubitus ulcers which are resistant to conventional therapies and other treatment modalities such as hyperbaric oxygen, vacuum-assisted closure, and surgical debridement.

Beneficial effects of extracts from Lucilia sericata maggots on burn wounds in rats

Lucilia sericata maggots have beneficial properties; however, their protective effects on burn wounds have yet to be fully elucidated. In the present study, a deep second‑degree burn rat model was used to investigate the burn wound healing properties of aqueous extract of maggots (MAE). The anti‑inflammatory, antioxidative and antibacterial activities were examined. In addition, the protein expression levels of Akt, vascular endothelial growth factor A (VEGFA) and nuclear factor‑κB (NF‑κB) were detected by western blotting. The findings of the present study revealed that MAE treatment increased burn wound healing and hydroxyproline content in the burn‑treated rats. A total of seven compounds (MAE‑P1‑P7) were separated from MAE and a comparative study was performed to identify the major active component. The results demonstrated that MAE‑P6 exerted greater antibacterial activity compared with the other compounds. MAE‑P6 treatment reduced tissue levels of malondialdehyde, tumor necrosis factor‑α and interleukin‑6, and increased superoxide dismutase activity. Furthermore, MAE‑P6 increased the expression levels of VEGFA and reduced NF‑κB expression through Akt, which was verified by treatment with the Akt‑specific inhibitor, LY294002. In conclusion, the present study demonstrated that the beneficial effects of MAE on burn wound healing were due to its antibacterial, antioxidative and anti‑inflammatory activities. MAE‑P6 reduced the release of inflammatory cytokines via the Akt/NF‑κB signaling pathway, and regulated angiogenesis and vasopermeability via the Akt/VEGFA pathway.

A new method for the production of sterile colonies of Lucilia sericata

Maggot debridement therapy (MDT) refers to the use of blowfly larvae to clean or debride an infected wound. Most commonly, larvae of Lucilia sericata (Meigen) (Diptera: Calliphoridae) are used, and are sterilized prior to use to ensure no further bacterial infections are introduced during treatment. Current methods sterilize eggs from laboratory-reared blowfly colonies, after which sterile early second instar maggots can be provided to hospitals for use in treatment. Maggots not required for treatment are used for colony regeneration, in which sterility is not maintained. The ability to maintain sterility beyond this would allow further research into fly-bacteria interactions and the effects of different bacteria on the blowfly lifecycle. This study aimed to produce a colony of sterile adults, using current egg sterilization practice, but maintaining sterility through to pupation and emergence. The production of a sterile colony allows further research into the impact of bacteria on fly development and survival. Eggs were placed on a sterile food source within autoclaved plant tissue culture containers to allow growth under sterile conditions. Nutrient agar plating of sterilized and non-sterilized eggs, larvae and adults (post-emergence), as well as the pupation medium and feed source in nutrient broth confirmed the aerobic sterility of all samples involved. The lifecycle of L. sericata was successfully completed through pupation to emergence with no effects on lifespan or oviposition by the newly emerged, sterile adult colony.

Urate Oxidase produced by Lucilia sericata medical maggots is localized in Malpighian tubes and facilitates allantoin production

Lucilia sericata maggots are the only species currently approved for maggot debridement therapy (MDT), an alternative treatment for chronic and recalcitrant wounds. Maggots promote wound debridement, disinfection and healing by producing a complex mixture of proteins, peptides and low-molecular-weight compounds in their secretions and excretions, but the individual components are not well characterized at the molecular level. Here we investigated the purine catabolism pathway in L. sericata, focusing on the production of allantoin by Urate Oxidase (UO), which is thought to promote wound healing. We produced recombinant L. sericata UO in Escherichia coli, and characterized the properties of the pure enzyme in terms of the optimum pH (7-10) and temperature (20-25 °C), its stability, sensitivity to inhibition and ion dependency. We used quantitative RT-PCR and RNA in situ hybridization to monitor the expression of the UO gene, and we used a guinea pig anti-UO antibody to detect the native enzyme by western blot and by florescence immunohistochemistry in larval tissues. We found that L. sericata UO is exclusively present in the larval excretion organ (the Malpighian tubes) and is freely available in the cytoplasm rather than restricted to a specific subcellular compartment. Allantoin is a final product of L. sericata purine catabolism. It is produced by UO in the Malpighian tubes to remove uric acid from the hemolymph and is consequently excreted via the hindgut. Our findings confirm the hypothesis that both actively secreted molecules and excretion products contribute to the beneficial effects of MDT.

Cost effectiveness of adding clostridial collagenase ointment to selective debridement in individuals with stage IV pressure ulcers

OBJECTIVE

The purpose of this study was to determine the cost effectiveness (from a payer's perspective) of adding clostridial collagenase ointment (CCO) to selective debridement compared with selective debridement alone (non-CCO) in the treatment of stage IV pressure ulcers among patients identified from the US Wound Registry.

METHODS

A 3-state Markov model was developed to determine costs and outcomes between the CCO and non-CCO groups over a 2-year time horizon. Outcome data were derived from a retrospective clinical study and included the proportion of pressure ulcers that were closed (epithelialized) over 2 years and the time to wound closure. Transition probabilities for the Markov states were estimated from the clinical study. In the Markov model, the clinical outcome is presented as ulcer-free weeks, which represents the time the wound is in the epithelialized state. Costs for each 4-week cycle were based on frequencies of clinic visits, debridement, and CCO application rates from the clinical study. The final model outputs were cumulative costs (in US dollars), clinical outcome (ulcer-free weeks), and incremental cost-effectiveness ratio (ICER) at 2 years.

RESULTS

Compared with the non-CCO group, the CCO group incurred lower costs ($11,151 vs $17,596) and greater benefits (33.9 vs 16.8 ulcer-free weeks), resulting in an economically dominant ICER of -$375 per ulcer. Thus, for each additional ulcer-free week that can be gained, there is a concurrent cost savings of $375 if CCO treatment is selected. Over a 2-year period, an additional 17.2 ulcer-free weeks can be gained with concurrent cost savings of $6,445 for each patient.

CONCLUSIONS

In this Markov model based on real-world data from the US Wound Registry, the addition of CCO to selective debridement in the treatment of pressure ulcers was economically dominant over selective debridement alone, resulting in greater benefit to the patient at lower cost.

Viability of Lucilia sericata maggots after exposure to wound antiseptics

After debridement and before dressing a wound with maggots of calliphorid flies, one frequently performed step is the application of antiseptics to the prepared wound bed. However, the concomitant application of antiseptic agents during maggot therapy is regarded controversial as antiseptics may interfere with maggots' viability. In this experimental in vitro study, the viability of fly maggots was investigated after exposure to various antiseptics frequently used in wound care. Here, we show that Lucilia sericata fly maggots can survive up to an hour's exposure to wound antiseptics such as octenidine, povidone-iodine or polihexanide. Concomitant short-term application of wound antiseptics together with maggots on wound beds is tolerated by larvae and does not impair their viability.

Traditional Therapies for Skin Wound Healing

Significance: The regeneration of healthy and functional skin remains a huge challenge due to its multilayer structure and the presence of different cell types within the extracellular matrix in an organized way. Despite recent advances in wound care products, traditional therapies based on natural origin compounds, such as plant extracts, honey, and larvae, are interesting alternatives. These therapies offer new possibilities for the treatment of skin diseases, enhancing the access to the healthcare, and allowing overcoming some limitations associated to the modern products and therapies, such as the high costs, the long manufacturing times, and the increase in the bacterial resistance. This article gives a general overview about the recent advances in traditional therapies for skin wound healing, focusing on the therapeutic activity, action mechanisms, and clinical trials of the most commonly used natural compounds. New insights in the combination of traditional products with modern treatments and future challenges in the field are also highlighted. Recent Advances: Natural compounds have been used in skin wound care for many years due to their therapeutic activities, including anti-inflammatory, antimicrobial, and cell-stimulating properties. The clinical efficacy of these compounds has been investigated through in vitro and in vivo trials using both animal models and humans. Besides the important progress regarding the development of novel extraction methods, purification procedures, quality control assessment, and treatment protocols, the exact mechanisms of action, side effects, and safety of these compounds need further research. Critical Issues: The repair of skin lesions is one of the most complex biological processes in humans, occurring throughout an orchestrated cascade of overlapping biochemical and cellular events. To stimulate the regeneration process and prevent the wound to fail the healing, traditional therapies and natural products have been used with promising results. Although these products are in general less expensive than the modern treatments, they can be sensitive to the geographic location and season, and exhibit batch-to-batch variation, which can lead to unexpected allergic reactions, side effects, and contradictory clinical results. Future Directions: The scientific evidence for the use of traditional therapies in wound healing indicates beneficial effects in the treatment of different lesions. However, specific challenges remain unsolved. To extend the efficacy and the usage of natural substances in wound care, multidisciplinary efforts are necessary to prove the safety of these products, investigate their side effects, and develop standard controlled trials. The development of good manufacturing practices and regulatory legislation also assume a pivotal role in order to improve the use of traditional therapies by the clinicians and to promote their integration into the national health system. Current trends move to the development of innovative wound care treatments, combining the use of traditional healing agents and modern products/practices, such as nanofibers containing silver nanoparticles, Aloe vera loaded into alginate hydrogels, propolis into dressing films, and hydrogel sheets containing honey.

Maggot debridement therapy as primary tool to treat chronic wound of animals

Maggot debridement therapy (MDT) is a safe, effective, and controlled method ofhealing of chronic wounds by debridement and disinfection. In this therapy live, sterile maggots of green bottle fly, Lucilia (Phaenicia) sericata are used, as they prefernecrotic tissues over healthy for feeding. Since centuries, MDT is used in humanbeings to treat chronic wounds. Lately, MDT came out as a potent medical aid in animals. In animals, although, this therapy is still limited and clinical studies are few. However, with the increasing antibiotic resistance and chronic wound infections in veterinary medicine, maggot therapy may even become the first line of treatment for some infections. This paper will present a brief discussion of MDT and its role in veterinary medicine that may add one more treatment method to utilize in non-healing wounds of animals and overcome the use of amputation and euthanasia. The objective of this review paper is to assemble relevant literature on maggot therapy to form a theoretical foundation from which further steps toward clinical use of maggot therapy in animals for chronic wounds can be taken.

Next Generation Sequencing Identifies Five Major Classes of Potentially Therapeutic Enzymes Secreted by Lucilia sericata Medical Maggots

Lucilia sericata larvae are used as an alternative treatment for recalcitrant and chronic wounds. Their excretions/secretions contain molecules that facilitate tissue debridement, disinfect, or accelerate wound healing and have therefore been recognized as a potential source of novel therapeutic compounds. Among the substances present in excretions/secretions various peptidase activities promoting the wound healing processes have been detected but the peptidases responsible for these activities remain mostly unidentified. To explore these enzymes we applied next generation sequencing to analyze the transcriptomes of different maggot tissues (salivary glands, gut, and crop) associated with the production of excretions/secretions and/or with digestion as well as the rest of the larval body. As a result we obtained more than 123.8 million paired-end reads, which were assembled de novo using Trinity and Oases assemblers, yielding 41,421 contigs with an N50 contig length of 2.22 kb and a total length of 67.79 Mb. BLASTp analysis against the MEROPS database identified 1729 contigs in 577 clusters encoding five peptidase classes (serine, cysteine, aspartic, threonine, and metallopeptidases), which were assigned to 26 clans, 48 families, and 185 peptidase species. The individual enzymes were differentially expressed among maggot tissues and included peptidase activities related to the therapeutic effects of maggot excretions/secretions.

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.

Maggot Debridement Therapy in Disaster Medicine

BACKGROUND

When disaster strikes, the number of patients requiring treatment can be overwhelming. In low-income countries, resources to assist the injured in a timely fashion may be limited. As a consequence, necrosis and wound infection in disaster patients is common and frequently leads to adverse health outcomes such as amputations, chronic wounds, and loss of life. In such compromised health care environments, low-tech and cheap wound care options are required that are in ready supply, easy to use, and have multiple therapeutic benefits. Maggot debridement therapy (MDT) is one such wound care option and may prove to be an invaluable tool in the treatment of wounds post-disaster.

DISCUSSION

This report provides an overview of the wound burden experienced in various types of disaster, followed by a discussion of current treatment approaches, and the role MDT may play in the treatment of complex wounds in challenging health care conditions. Maggot debridement therapy removes necrotic and devitalized tissue, controls wound infection, and stimulates wound healing. These properties suggest that medicinal maggots could assist health care professionals in the debridement of disaster wounds, to control or prevent infection, and to prepare the wound bed for reconstructive surgery. Maggot debridement therapy-assisted wound care would be led by health care workers rather than physicians, which would allow the latter to focus on reconstructive and other surgical interventions. Moreover, MDT could provide a larger window for time-critical interventions, such as fasciotomies to treat compartment syndrome and amputations in case of life-threatening wound infection.

RECOMMENDATIONS

There are social, medical, and logistic hurdles to overcome before MDT can become widely available in disaster medical aid. Thus, research is needed to further demonstrate the utility of MDT in Disaster Medicine. There is also a need for reliable MDT logistics and supply chain networks. Integration with other disaster management activities will also be essential.

CONCLUSIONS

In the aftermath of disasters, MDT could play an important role facilitating timely and efficient medical treatment and improving patient outcomes. Existing social, medical, and logistic barriers will need to be overcome for MDT to be mainstreamed in Disaster Medicine.

Challenges in the Treatment of Chronic Wounds

Significance: Chronic wounds include, but are not limited, to diabetic foot ulcers, venous leg ulcers, and pressure ulcers. They are a challenge to wound care professionals and consume a great deal of healthcare resources around the globe. This review discusses the pathophysiology of complex chronic wounds and the means and modalities currently available to achieve healing in such patients. Recent Advances: Although often difficult to treat, an understanding of the underlying pathophysiology and specific attention toward managing these perturbations can often lead to successful healing. Critical Issues: Overcoming the factors that contribute to delayed healing are key components of a comprehensive approach to wound care and present the primary challenges to the treatment of chronic wounds. When wounds fail to achieve sufficient healing after 4 weeks of standard care, reassessment of underlying pathology and consideration of the need for advanced therapeutic agents should be undertaken. However, selection of an appropriate therapy is often not evidence based. Future Directions: Basic tenets of care need to be routinely followed, and a systematic evaluation of patients and their wounds will also facilitate appropriate care. Underlying pathologies, which result in the failure of these wounds to heal, differ among various types of chronic wounds. A better understanding of the differences between various types of chronic wounds at the molecular and cellular levels should improve our treatment approaches, leading to better healing rates, and facilitate the development of new more effective therapies. More evidence for the efficacy of current and future advanced wound therapies is required for their appropriate use.

Pressure ulcers: Current understanding and newer modalities of treatment

This article reviews the mechanism, symptoms, causes, severity, diagnosis, prevention and present recommendations for surgical as well as non-surgical management of pressure ulcers. Particular focus has been placed on the current understandings and the newer modalities for the treatment of pressure ulcers. The paper also covers the role of nutrition and pressure-release devices such as cushions and mattresses as a part of the treatment algorithm for preventing and quick healing process of these wounds. Pressure ulcers develop primarily from pressure and shear; are progressive in nature and most frequently found in bedridden, chair bound or immobile people. They often develop in people who have been hospitalised for a long time generally for a different problem and increase the overall time as well as cost of hospitalisation that have detrimental effects on patient's quality of life. Loss of sensation compounds the problem manifold, and failure of reactive hyperaemia cycle of the pressure prone area remains the most important aetiopathology. Pressure ulcers are largely preventable in nature, and their management depends on their severity. The available literature about severity of pressure ulcers, their classification and medical care protocols have been described in this paper. The present treatment options include various approaches of cleaning the wound, debridement, optimised dressings, role of antibiotics and reconstructive surgery. The newer treatment options such as negative pressure wound therapy, hyperbaric oxygen therapy, cell therapy have been discussed, and the advantages and disadvantages of current and newer methods have also been described.

Maggot excretion products from the blowfly Lucilia sericata contain contact phase/intrinsic pathway-like proteases with procoagulant functions

For centuries, maggots have been used for the treatment of wounds by a variety of ancient cultures, as part of their traditional medicine. With increasing appearance of antimicrobial resistance and in association with diabetic ulcers, maggot therapy was revisited in the 1980s. Three mechanisms by which sterile maggots of the green bottle fly Lucilia sericata may improve healing of chronic wounds have been proposed: Biosurgical debridement, disinfecting properties, and stimulation of the wound healing process. However, the influence of maggot excretion products (MEP) on blood coagulation as part of the wound healing process has not been studied in detail. Here, we demonstrate that specific MEP-derived serine proteases from Lucilia sericata induce clotting of human plasma and whole blood, particularly by activating contact phase proteins factor XII and kininogen as well as factor IX, thereby providing kallikrein-bypassing and factor XIa-like activities, both in plasma and in isolated systems. In plasma samples deficient in contact phase proteins, MEP restored full clotting activity, whereas in plasma deficient in either factor VII, IX, X or II no effect was seen. The observed procoagulant/intrinsic pathway-like activity was mediated by (chymo-) trypsin-like proteases in total MEP, which were significantly blocked by C1-esterase inhibitor or other contact phase-specific protease inhibitors. No significant influence of MEP on platelet activation or fibrinolysis was noted. Together, MEP provides contact phase bypassing procoagulant activity and thereby induces blood clotting in the context of wound healing. Further characterisation of the active serine protease(s) may offer new perspectives for biosurgical treatment of chronic wounds.

Maggots as potential vector for pathogen transmission and consequences for infection control in waste management

BACKGROUND AND AIMS

Debridement therapy with sterile bred larvae in non-healing wounds is a widely accepted safe and efficient treatment modality. However, during application in the contaminated wound bed microbial contamination with potential microbial pathogen spread after escape from the wound or after unreliable disposal procedure may happen, particularly in the case of not using bio-bags. The aims of this work were first to investigate the release of ingested bacteria into the environment by maggots and second to examine the common practice of freezing the maggots after use and/or disposal in trash-bags. Potential methods for hygienic safe disposal of used maggots should be deduced.

METHODS

First, Maggots were contaminated with S. aureus by allowing them to crawl over an agar surface completely covered with bacterial growth over 24 h at 37°C. After external disinfection maggots were transferred onto sterile Columbia agar plates and shedding of S. aureus was visualized. Second, maggots were frozen at -20°C for 1, 2, 5, 10, 30, and 60 min. After exposure, the larvae were transferred onto Columbia blood agar with consecutive incubation at 37°C over 48 h. The larvae were analyzed visually for mobility and eating activities. The frozen bodies of dead larvae were examined for viable bacteria.

RESULTS

We could demonstrate that maggots release formerly ingested pathogens (S. aureus). Freezing at -20°C for at least 60 min was able to kill all maggots, however the contaminant bacteria inside could survive.

CONCLUSION

Since freezing is apparently able to kill maggots but not to reliabely inactivate the ingested bacterial pathogens, we recommend the disposal of free-range larvae in screw cap vials after use to achieve full hygienic control.

Fauna europaea: Diptera - brachycera

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small-sized species may be considered as taxonomically more challenging. Most of Europe is highly industrialised and has a high human population density, and the more fertile habitats are extensively cultivated. This has undoubtedly increased the extinction risk for numerous species of brachyceran flies, yet with the recent re-discovery of Thyreophoracynophila (Panzer), there are no known cases of extinction at a European level. However, few national Red Lists have extensive information on Diptera. For the Diptera-Brachycera, data from 96 families containing 11,751 species are included in this paper.

Selective Antibiofilm Effects of Lucilia sericata Larvae Secretions/Excretions against Wound Pathogens

Background. Maggot debridement therapy (MDT), using Lucilia sericata larvae, represents efficient, simple, and low-cost therapy for the treatment of chronic wounds. Aim. The aim was to investigate the antibiofilm activity of maggot excretions/secretions (ES) against biofilm of wound isolates Staphylococcus aureus (S. aureus), Enterobacter cloacae (E. cloacae), and Proteus mirabilis (P. mirabilis). Methods. Quantification of biofilm formation, was carried out using a microtiter plate assay. Proteolytic activity of maggot ES was performed using skim milk agar plates. A solid phase extraction and reverse phase HPLC C18 chromatography were employed to the isolate of maggot ES antibiofilm compounds. Results. Maggot ES at 100 mg/mL concentration significantly reduced biofilm formation thus disrupting established biofilm of E. cloacae. Heat-treated ES did not show any antibiofilm activity towards E. cloacae. Similar results were obtained in the case of S. aureus; however, the heat-treatment of maggot ES did not affect its antibiofilm activity. Moreover, a compound with molecular weight of 25 kDa exhibiting antibiofilm activity was identified in maggot ES. On the other hand, maggot ES protected and even stimulated P. mirabilis biofilm formation. Conclusions. Our results suggest that maggot ES may act selectively against different bacterial strain.

Maggot Therapy for Elephantiasis Nostras Verrucosa Reveals New Applications and New Complications: A Case Report

Elephantiasis nostras verrucosa (ENV) is a rare dermatologic condition caused by chronic nonfilarial lymphedema. The treatment for ENV is challenging and based solely on case reports. We report novel therapy for ENV with maggot debridement therapy (MDT), an effective wound therapy that has gained popularity with the rise of antimicrobial resistance. MDT, in combination with tangential surgical debridement, was effective in the treatment of ENV. In nature, sheep infested with more than 16 000 blow fly larvae exhibit ammonia toxicity. Although hyperammonemia as a side effect of maggot therapy has been theorized, its existence has not been described in human studies until this case. This patient exhibited hyperammonemia during maggot therapy; with alterations in serum ammonia reflecting changes in larval population. Maggot therapy should be considered for the treatment of ENV. Hyperammonemia with maggot therapy exists, and clinicians who employ this treatment should be aware of this potential adverse effect.

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.

Maggot debridement therapy for peripheral arterial disease

INTRODUCTION

Maggots are potent debriding agents capable of removing necrotic tissue and slough; however, it is still unclear which wounds are most likely to benefit from maggot debridement therapy (MDT). Thus, we performed this retrospective review to gain insight into the patient and therapy characteristics influencing outcome.

PATIENTS AND METHODS

We reviewed patients with foot ulcers caused by critical limb ischemia, encountered during the period between June 2005 and May 2010. The treatment outcomes were defined as effective or ineffective.

RESULTS

There were 16 patients with 16 leg ulcers. The patients were 13 men and 3 women, with an average age of 67.2 years (range, 47-85 years). Ten (63%) of the 16 ulcers were treated effectively. According to univariate analyses, an ankle brachial pressure index (ABI) lower than 0.6 (p = 0.03) had a negative impact on the outcome of MDT; however, outcome was not influenced by gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, smoking, or laboratory findings.

CONCLUSIONS

Some patient characteristics, such as gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, and smoking, do not seem to contraindicate eligibility for MDT. However, a limb with an ABI lower than 0.6 is less likely to benefit. (English Translation of J Jpn Coll Angiol 2011; 51: 209-213.).