http://chronicle.com/weekly/v53/i39/39a04801.htm
From the issue dated June 1, 2007
NOTES FROM ACADEME
Rx: Maggots
By PETER MONAGHAN
Irvine, Calif.
If you'd like to hold your festering wound still for a moment, Ronald A. Sherman can plaster up to a thousand live maggots onto it and let them feed there until each grows to about the size of a cooked grain of rice.
Any takers?
This is not Dr. Sherman seeing how thoroughly he can abuse his Hippocratic oath. On the contrary, he is administering a medical treatment that he has been instrumental in reviving.
For 20 years, Dr. Sherman has been trying to make colleagues and patients aware that this use of fly larvae — practiced long before Hippocrates and other medical sages ever wielded mortar and pestle — may actually save limb and even life.
Indeed, on the battlefields of the American Civil War medics observed that while soldiers were understandably horrified to find their wounds writhing with maggots, such infestation might actually be a good thing. "Surgeons noticed that soldiers with wounds infested by maggots recovered better, and died less often, than soldiers with similar wounds that weren't infested," says Dr. Sherman, an assistant researcher in pathology at the University of California at Irvine who is the country's most active advocate of maggot-debridement therapy. (Debridement refers to the stripping away of dead tissue, which maggots achieve with impressive speed.)
The treatment was widely used from the 1920s to the 1940s, when it was supplanted by antibiotics.
In its revived form, sterile maggots treat conditions that are resistant to antibiotics. Many such conditions are suffered by diabetics, but patients also include victims of accidents and attacks, or the homeless, who contend with such ailments as gangrene.
The medical complaints that invoke larval therapy come with names as forbidding as the conditions are grim: neuropathic foot wounds, venous ulcers, necrotic tumors, nonhealing postoperative wounds. Not for the squeamish are case-study images of sepsis, malodorous exudate, and guillotine amputation of toes or feet.
And so, on a recent afternoon here, Dr. Sherman shows a small group of doctors and nurses how to apply maggots to sores in order to clear away dead tissue, clean the wounds, and kindle new growth.
Workshop participants work not with suppurating sores, but with plastic models. They practice shaking real maggots out of vials onto specialized bandages that they apply to make-believe wounds. No bigger than grains of sand, these maggots are devilishly hard to see.
Dr. Sherman, slight and mild in manner, seems to relish, just a little, his descriptions of his beloved larvae. "They are eating machines," he tells his charges. "They don't have to stop eating to breathe." While noshing via tiny beaks buried in the dead flesh, they ventilate via two ports at their rears. They eat too fast to digest as they go, so they store food in their crops for later. They also predigest necrotic tissue — they drool protein-dissolving enzymes into wounds and imbibe the resulting mash.
"You don't want any maggots to get away," Dr. Sherman cautions. Having gorged themselves, maggots always rush off. Thank evolution: If they hung around on carrion until larger animals arrived, they would be gobbled up.
During a break, the workshop participants manage, somehow, to eat lunch, and Dr. Sherman relates his own conversion to maggot healer. After majoring in entomology, he went to medical school at the University of California at Los Angeles in the early 1980s and became interested in parasitology. "Normally that deals with insects that cause disease, or vector it," he explains. "But I had been introduced, along the way, to the therapeutic uses of insects, and that appealed to me."
One day a surgery resident tagged Mr. Sherman as a fellow insect fan — it was the butterfly-daubed bow tie — and invited him onto a study of maggot therapy. Instantly, says Dr. Sherman, "I was hooked." He took to collecting maggots from wounded patients in the hospital, "just to see them and to understand them." He proposed his own clinical study of maggot therapy, but couldn't find the flies he needed. "I had to go out and catch my own," he says. He spent months laying out meat and netting flies.
The promise of good results from myiasis, or controlled infestation, drew him on. "I was seeing lots of wounds and being asked to treat them with antibiotics," he says, "but those were failing."
Maggot therapy is now used on more than 10,000 patients each year, according to international advocacy groups, but only about 5 percent of those are in the United States. Most American patients have Dr. Sherman to thank for establishing a sterile supply. After lunch, he gives a tour of his maggot-hatching facility.
Monarch Labs, a few rooms fashioned from warehouse space, sits under the landing approach to John Wayne Airport. It is a factory whose laborers are flies.
Seven species produce acceptable medical maggots, but the preferred one by far is Phaenicia (Lucilia) sericata, the green blowfly. It is classified as a facultative myiasis species, which means that it limits itself to eating dead tissue. Any patient who has a few thousand applied under a dressing appreciates that trait because insects that eat live tissue hurt. A lot.
Despite the din of aircraft close overhead, Monarch's Phaeniciae sericatae toil day and night to produce eggs that will hatch as larvae that ship out, air express, to some 600 medical facilities nationwide.
Inside each of 30 cloth-enclosed cages, about 2,000 flies enjoy soy feed and lay eggs. Visitors can view the cages from behind glass. Or, says Dr. Sherman, "if you'd like to go into the insectary, feel free; but I should warn you. ... "
The brave-enough soon discover what he means. Amid a faint buzz of busy residents, the fly room stinks like an overripe butcher's shop, but without the consolation of aromatic sawdust.
Perhaps by way of apology, Dr. Sherman says he hopes that biochemistry and molecular biology will lead him one day to a medication that achieves maggotlike debridement and repair, sans the maggots.
As specialists in the field are few, he has also taken on such tasks as understanding how patients and doctors respond to the technique. He finds that patients generally put up less resistance, "probably because they have already endured the hassles of a chronic, nonhealing wound." In almost all cases, doctors first prescribe the therapy at patients' urging. Ironically, doctors resist it because they fear that patients will refuse it or that colleagues will mock them.
They will not, if Pamela Mitchell, Dr. Sherman's staunchest supporter, has her way. A diabetic, she is often on hand when he has converts to make. After all, maggots saved her legs, and probably her life, after she persuaded her own reluctant doctors to give them a try rather than amputate her feet.
Now a board member of the BioTherapeutics, Education, & Research Foundation, which Dr. Sherman set up to disseminate the method, she tells workshop participants that naturopaths, podiatrists, and veterinarians, particularly equine podiatrists, have taken to maggot therapy far more readily than M.D.'s. "I had to become my own patient advocate," she says.
She had had many treatments to try to close and heal her foot ulcers, at a cost of $40,000. Ten applications of munching microsurgeons, over the course of a year, cost $1,000.
"As repulsive as they seemed at first," she says, "I quickly started to look at the maggots as my little buddies."
Copyright © 2008 by The Chronicle of Higher Education
