Ever get that creepy-crawly sensation, like bugs are slithering beneath your skin? For some people, the feeling is permanent. They complain that their skin is infested by insects or parasites — a condition they call Morgellons disease, but that dermatologists have long described as a delusion. Now a new study confirms that these perceived infestations do in fact have more to do with the brain than actual bugs.
As proof of infestation, people who say they have Morgellons disease often pick filaments and fibers from their skin, which they say were caused by bugs. They bring insects to doctors saying the critters emerged from their skin. So for their new study, researchers from the Mayo Clinic decided to review 108 such patients and the 80 specimens the patients provided. The patients were seen at the clinic over a seven-year period ending in 2007. Eighty people received biopsies.
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The final diagnosis: “delusional skin infestation.” Rather than parasites, the researchers found that more than 60% of patients had dermatitis, a common condition that causes rashes and inflamed, itchy skin that could be misinterpreted as a bug infestation by sufferers. Other patients had skin ulcerations, erosions and other problems — often caused by picking and scratching at the skin — but none could be attributed to parasitic infestation.
Among the 80 specimens the patients brought in, 10 were insects that the patients said had come from their skin, but none were capable of body infestation. In one case, a patient produced a pubic louse, which can infest, but as WebMD pointed out, is incapable of causing “head-to-toe itching.” (Other samples included a mite, a tick and two fruit flies.)
As for the fibers and filaments that sufferers produced as signs of parasites, they were “upon microscopic examination, skin flakes, scabs, hair, lint, textile fiber and everyday debris,” the Los Angeles Times reported.
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But despite evidence to the contrary, many patients are unlikely to be convinced that they have anything but Morgellons disease. Suggesting they have a psychiatric disorder or that they may need medication only agitates them, doctors say. “They are very upset because they believe their skin is infested with all sorts of nasty things and we don’t see anything or find anything with a biopsy and yet they are in our office, their lives are ruined, and they want treatment,” Dr. Mark Davis, professor of dermatology at the Mayo Clinic, told WebMD. “Patients say ‘you are just missing it and not looking carefully enough,’ and just walk out.”
The study’s authors write:
This study is important for patients. Patients frequently believe that physicians are dismissive of their concerns and are not examining their skin closely enough, and therefore patients request that more testing be performed. This showed that biopsy results do not change a physician’s clinical diagnosis of delusional infestation.
It’s not known exactly how many people believe they suffer from skin infestation, but those who do are determined to seek answers to their problem. They have even convinced the U.S. government to conduct a study. The Los Angeles Times reports:
Results of another, three-year study, undertaken by the Centers for Disease Control and Prevention and Kaiser Permanente of Northern California, are slated for release in the next few months. That study was launched in January 2008 after patients and a small group of medical professionals led by an organization called the Morgellons Research Foundation advocated for a full-scale government investigation of their symptoms.
The current study was published online May 16 by the Archives of Dermatology.
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