Elective use of maggots in septic diabetic foot

This 60 year old, male diabetic patient was referred to me by his General Practitioner with a neuropathic ulcer on the plantar aspect (sole of the foot)when his podiatrist went on leave. He had been under the podiatrists care for more than 12 months with little result. He walked into the clinic in tight fitting shoes, random blood sugar was 13mmol/L, HbA1C (average blood sugar calculated over preceding 8 weeks) was 15mmol/L. Blood pressure was 140/90mmHg, A.C.E. inhibitor had been prescribed for high blood pressure. His left foot was the size and shape of a rugby ball, erythema  (redness) extended from the foot to just below the knee. The foot and leg were both quite warm to touch. Ankle Brachial Pressure Index (ABPI) was not done due to oedema (swelling) of the foot.

Once again, I was faced with one of the most challenging patients to treat....single, self employed, male, diabetic! Added to this, he had no Medical aid or hospital plan! Here I had an apparently uncooperative, uncontrolled diabetic patient who was expecting me to save his lower leg. Sadly patients, especially diabetic patients, believe that dressings, wound healing specialists and doctors heal wounds. Only after a few treatments where patients have adhered to the treatment plan, do they realize that they control the rate at which they heal themselves. This patient was no exception. Although, I must add, that he really surprised me in that he eventually stuck to the treatment plan more closely than most other patients I have treated. I dare say, I did have to first listen to why he couldn't offload (not walk on his foot), and help him re plan his daily activities, like pack a cooler box with the day's meals and snacks in it to limit the number of trips to the kitchen. Since the moonboot apparently hadn't helped relieve pressure in 12 months, he agreed to use crutches for short trips to the bathroom and a wheel chair for the longer ones. Low G.I. (Glycaemic Index) diet was explained and meals were planned.

After my initial assessment of this patient, it was abundantly obvious that he needed hospitalization and a surgical debridement to save his leg. There was callus around the plantar wound which needed to be debrided. The hospital had quoted him around R95 000.00 to do a surgical debridement (cut away dead tissue) and 2 days of ICU (Intensive Care Unit), which he simply could not afford. ICU was needed to regain blood sugar control which would be very important to prevent new necrosis (dead tissue) developing. It was most fortunate that his landlady was a doctor who assisted by administering intravenous antibiotics for him at home. Intravenous antibiotics were needed for two reasons, firstly the concentration of antibiotic in the infected tissue is higher than with oral antibiotics resulting in faster response, and secondly because the foot was so oedematous (swollen), microvascular (very tiny arteries and veins) blood supply would be compromised resulting in poor antibiotic delivery to the infected tissue. Remember that the microvascular blood supply is responsible for delivering the antibiotic to the infected tissue. Here I need to add another fact which patients frequently don't understand, is that antibiotics don't penetrate dead tissue. Dead tissue contains dead blood vessels which don't transport anything. Patients so frequently insist on being prescribed antibiotics for infected wounds which are well populated with necrotic tissue. Sadly, many therapists support this view, when in fact, the cause of the infection remains the dead tissue which should be removed ASAP, followed by the correct antibiotics. Having said that, I feel I should explain that we prescribe antibiotics in two ways.Empirically, when there is a limb or life threatening infection and we don't know which bacteria is responsible for the infection or to which antibiotic the bacteria will be sensitive to, and therapeutically when we know exactly which bacteria is responsible for the infection. When we treat empirically, we usually look at the location of the wound, the chronicity (how long the wound has existed) of the wound and prescribe a suitable broad spectrum antibiotic. It should be noted that a sample of dead tissue should be sent the laboratory for an MC&S (Microscopic, Culture and Sensitivity) to establish if the empirically prescribed antibiotics are the correct ones, before antibiotics are started. If the results of the MC&S show that we have chosen the wrong antibiotics empirically, we can easily change to the most appropriate one. This is usually spot on when prescribed by an experienced doctor. When the infection is less serious, we have the luxury of time and can wait for the MC&S results which take about 3 days, before we start with most appropriate and normally narrow spectrum antibiotics.

At this patients first visit to the clinic, I drained the abscess but did not debride (cut away dead tissue) the wound since he had convinced me that he would be able to go for a surgical debridement (cutting away dead tissue in a hospital theatre). He only contacted me 3 days later for an appointment to see me. He informed me that he could not afford the hospital account and had thus not had the surgical debridement, fortunately he did have the intravenous antibiotics though. A friend had transported him to the clinic and he gratefully entered on a wheelchair..... at least offloading had obviously hit home. After washing the lower leg under a hand held shower, I cleaned the wound with warm sterile water, sharp debrided (cut away dead tissue without anaesthesia) until I could no longer see where or what I was cutting, when his friend asked about maggots. My blood ran cold, no, it probably froze!  I hate worms, any worms, what a predicament. This was the most challenging position I have ever found myself in. Allow me to add some details about this darn phobia for worms. My children have often run into the kitchen when I have cut into a fruit or veggie and discovered a worm. Why, you may ask? Because I go ballistic! Hysteria has no comparison. So when I say I hate worms, it's an understatement! Now, I am expected to in voluntarily introduce these little creatures into a wound to remove the dead tissue which I can't. Brrrrrr. Cold chills ran down my spine, but it was the right choice. Oh heck! I was getting a little of my own medicine, forced to do what I didn't want to do.

 The patient consented and the little creatures (maggots) were introduced in 'teabag' form. The University of Pretoria farm maggots for wound management and package them in little bags. The maggots secrete an enzyme which liquefies only the necrotic (dead tissue) and the maggots then drink the liquid though the teabag. This was more acceptable to me than working with 20 or more wriggling, squirming little phobias, and it was also a little buffer for me. Unfortunately, in spite of following the instructions to the last dotted 'i' and crossed 't', only 3 maggots appear to have survived for a short period after I placed the teabag in the wound. I had dressed the wound with Drawtex and secured it with a transparent film dressing. The wound and dressing were malodorous, the surrounding tissue was severely macerated (white and wrinkly, like granny fingers), the wound appeared slightly better. The patient insisted that we continue with a new 'teabag', which we did. 3 days later the patient returned for a treatment and casually mentioned that his landlord had 'let the dogs out', meaning that the doctor had removed the teabag, cut it open and reintroduced the maggots as 'free range' maggots. Oh boy! You can imagine just how excited I was about doing THIS treatment. There were 1 cm long squirming little white maggots between the toes, under the toes, in the crepe bandage....the little creatures were everywhere! Ooooh, this was sooooo challenging. I reached for the 5 litre bottle of 10 volume peroxide, which I had bought on the same day as I bought the maggots, and proceeded to pour it over the foot, bandages and all! When I thought all the maggots were dead, a dared a peep at the foot. There were only about 2 maggots still half alive, another 2 litres of peroxided quickly remedied that. When I thought the coast was clear, I proceeded to irrigate the foot with the hand shower, flushing what seemed like a hundred maggots down the drain. To be sure they were ALL really dead and sterilized, I poured 2 litres of hydrochloric acid down the drain. Shew, the worst was over!

To my amazement,  the wound was significantly cleaner with little to no maceration of suurounding tissue.

Photographic record

This patient unfortunately has been forced to return to work. This includes more walking than would be acceptable for healing to continue to progress. Hopefully he will see this through to the end and wound closure can be achieved.

Once the wound is healed, he will be referred to the Orthotist for a foot scan which shows areas of high pressure under the foot while the patient is walking. The Orthotist will then make innersoles to help redistribute the pressure and reduce pressure in the area of the old ulcer. A very large percentage of neuropathic ulcer reoccur because scar tissue is not very strong, ever and is prone to premature breakdown under pressure.