Jacques Oskam

Maggot Debridement Therapy of Infected Ulcers: Patient and Wound Factors Influencing Outcome – A Study on 101 Patients with 117 Wounds

INTRODUCTION It has been known for centuries that maggots are potent debriding agents capable of removing necrotic tissue and slough. In January 2004, the US Food and Drug Administration decided to regulate maggot debridement therapy (MDT). As it is still not clear which wounds are likely or unlikely to benefit from MDT, we performed a prospective study to gain more insight in patient and wound characteristics influencing outcome. PATIENTS AND METHODS In the period between August 2002 and December 2005, patients with infected wounds with signs of gangrenous or necrotic tissue who seemed suited for MDT were enrolled in the present study. In total, 101 patients with 117 ulcers were treated. Most wounds were worst-case scenarios, in which maggot therapy was a treatment of last resort. RESULTS In total, 72 patients (71%) were classified as ASA III or IV. In total, 78 of 116 wounds (67%) had a successful outcome. These wounds healed completely (n = 60), healed almost completely (n = 12) or were clean at least (n = 6) at last follow-up. These results seem to be in line with those in the literature. All wounds with a traumatic origin (n = 24) healed completely. All wounds with septic arthritis (n = 13), however, failed to heal and led in half of these cases to a major amputation. According to a multivariate analysis, chronic limb ischaemia (odds ratio [OR], 7.5), the depth of the wound (OR, 14.0), and older age (>or= 60 years; OR, 7.3) negatively influenced outcome. Outcome was not influenced by gender, obesity, diabetes mellitus, smoking, ASA-classification, location of the wound, wound size or wound duration. CONCLUSIONS Some patient characteristics (i. e. gender, obesity, smoking behaviour, presence of diabetes mellitus and ASA-classification at presentation) and some wound characteristics (i. e. location of the wound, wound duration and size) do not seem to contra-indicate eligibility for MDT. However, older patients and patients with chronic limb ischaemia or deep wounds are less likely to benefit from MDT. Septic arthritis does not seem to be a good indication for MDT.

Maggot debridement therapy: free-range or contained? An in-vivo study.

OBJECTIVE: To determine which method of maggot debridement therapy- free-range or contained-is more effective for wound healing. METHODS: In vivo study of 64 patients with 69 chronic wounds that showed signs of gangrenous or necrotic tissue. Patients were treated with either free-range or contained maggot debridement therapy according to maggot availability, dressing difficulty, and physician preference. RESULTS: Significantly better outcomes were achieved with the free-range technique versus the contained technique (P = .028). With the free-range technique, the mean number of maggot applications and the total number of maggots per treatment were significantly lower than with the contained application technique (P = .028 and P < .001, respectively). CONCLUSION: This clinical in vivo study supports in vitro studies in which containment of maggots was found to reduce the effectiveness of maggot debridement therapy.

Maggot therapy and the "yuk" factor: an issue for the patient?

To the Editor: Maggot-therapy is a medical curiosity that has had little influence on the course of modern medicine, as predicted by the editor of the Medical Annual in 1933; this statement might have been true as late as 1988, but now with more than 100 papers published on the subject in the past decade alone, it’s no longer true. The history of the use of maggots in chronic or infected wounds for debridement goes back hundreds of years. It was introduced in the hospital in the early 1930s; after almost a complete absence for decennia, mainly caused by the introduction of antibiotics, the maggot has made a remarkable comeback. Maggots. The very word evokes images of rotting and decay. It’s very easy to understand why the mere thought of using these creatures on infected wounds would not be a pleasant thought for many people. It’s suggested that many patients are deterred by this therapy, mainly because of the ‘‘yuk factor,’’ but perhaps health care professionals have a bigger ‘‘yuk factor’’ as compared to patients. Placement of maggots in socalled ‘‘biobags’’ makes them invisible, easier to apply, and may reduce the ‘‘yuk factor’’ in health care professionals and patients. Others state that the acceptance of the therapy is high among patients. In a phenomenological study on six patients receiving maggot therapy, the experience of larval therapy was not as scary as imagined. We performed a survey among our patients to inquire whether the ‘‘yuk factor’’ is important for patients undergoing maggot therapy.

Exclusion of a crural pseudoaneurysm with a PTFE-covered stent-graft.

Purpose: To describe the successful endovascular treatment of an iatrogenic anterior tibial artery pseudoaneurysm with a polytetrafluoroethylene-covered stent-graft. Case Report: A 58-year-old man was admitted to our hospital with pseudoarthrosis and malunion of the right distal tibia. Fibulotomy and intramedullary fixation were performed, which was complicated by a pseudoaneurysm of the anterior tibial artery. Under local anesthesia, a 4×31-mm Symbiot covered stent was successfully placed over the origin of the pseudoaneurysm. At 12 months, the pseudoaneurysm remained excluded, and the anterior tibial artery was patent. Conclusions: Endovascular treatment of a crural artery pseudoaneurysm seems to be a feasible treatment option. Further experience with this technique is needed to validate its safety and long-term patency.

Deep Infection After Ilioinguinal Node Dissection: Vacuum-Assisted Closure Therapy?

Wound infection rates after ilioinguinal node dissection are high; 9% to 16% have been reported. The authors report a patient who underwent an ilioinguinal node dissection for a regional metastasized melanoma. Unfortunately, a deep wound infection occurred with extensive skin necrosis and production of abundant wound fluid (750 cc daily). Despite 6-daily dressings, the wound deteriorated, necessitating further operative debridement. In theatre, the authors failed to identify the lymphatic fistula and therefore were unable to close it. In accordance with literature on treatment of groin infections after vascular prosthesis, vacuum-assisted closure (VAC) therapy was started. After 11 days of VAC therapy, the lymphatic leakage completely stopped. Concurrent successful management of the wound with split skin graft therapy led to a complete closure of the wound. The treatment was not painful, changes of the sponge could be done in the ward, and there were no complications.

Maggot Debridement Therapy in the Palliative Setting

Success rates of Maggot Debridement Therapy (MDT) differ, but range from 70% to 80%. In this article it is argued that wound closure is not always feasible and is not always the aim of the treatment. A patient is described in whom the intent of MDT was not wound closure, but infection removal, reduction of odor, and eventually prevention of a below knee amputation. This succeeded: the pain was diminished, the odor reduced, and the wound showed signs of healing. Still the patient died. In maggot literature, as with other wound treatments, outcome is recorded as closed or as failed. In our opinion, MDT has other indications besides wound closure.

Comments on the paper, "The biosurgical wound debridement : experimental investigation of efficiency and practicability," by Blake FA et al.

To the Editor: We would like to congratulate Dr. Blake and his coauthors with their recent publication on Maggot Debridement Therapy (MDT). From their experimental study they concluded that the contained technique (Biobag) does not impair effectiveness of MDT. In their introduction it is stated that ‘‘to what extend this alternative (Biobag) impairs the effectiveness of the debridement has not been investigated.’’ This is not true, this has been studied and published before. Already in 2002 Thomas et al. published an experimental study called: The effect of containment on the properties of sterile maggots, in which they found that maggots were able to increase their weight in 48 hours to 23 times if they were used in the free-range technique, compared with an increase of only seven times if contained; this difference was highly significant. Our own study group published, in 2005 an in vivo study on the effect of containment. With the free-range technique, we found that the mean number of maggot applications (2.4 vs. 4.3 applications, p50.028) and the total number of maggots per treatment (156 vs. 277 maggots, p< 0.001) were significantly lower than with the contained application technique. Dr. Blake concluded that the effectiveness of the Biobag is comparable to the free-range technique, especially taking into account the time for dressing changes. This is interesting, for time of dressing changes was not studied in their published study. In Figure 4 of their article, it is shown how the effect of the Biobag is studied; it is shown how a Biobag is sewn to the necrotic tissue. It is clear that this situation is not applicable to in vivo studies. In fact most of the times the Biobag does not exactly cover the entire wound and the debridement is not thorough as with the free-range technique. Perhaps this could be overcome with a ‘‘personalized’’ Biobag in which the Biobag follows exactly the contours of the wound. Furthermore we would like to stress the differences in costs, the contained technique is about 40% more expensive compared with the free-range technique. Therefore, in our clinic, the free-range technique is the preferred technique (for dressing times are equal); the Biobag technique is used in special circumstances, like bleeding-disorders, patient preference and wounds close to large vessels or natural orifices.

Modern Wound Treatment of Infected Transtibial Amputation: Case Reports

Five patients with severe infection of transtibial amputations were treated with the use of maggot debridement therapy (MDT) and vacuum-assisted closure (VAC) therapy, resulting in fewer conversion rates to transfemoral amputation. Two patients are described in detail, and the treatment modalities of MDT and VAC are discussed.