Twenty individuals diagnosed with delusory parasitosis participated in a single site clinical study under the auspices of the National Pediculosis Association (NPA) and the Oklahoma State Department of Health. The objective of this study was to determine if there were any common factors in skin scrapings collected from this population. These individuals, whose symptoms were originally attributed to lice or scabies, were part of a larger group reporting symptoms of stinging/biting and/or crawling to the NPA. Multiple skin scrapings from each person were microscopically examined. Any and all fields of view that appeared incongruous to normal human skin were digitally photographed. When the photographic images were initially evaluated, no common factor was identified. However, more extensive scrutiny using imaging software revealed evidence of Collembola in 18 of the 20 participants.
Delusory parasitosis, also known as Ekbom’s Syndrome (Ekbom, 1938), is a presumed psychiatric condition ascribed to individuals who are convinced, in the absence of any empirical evidence, that they are infested with an insect or parasite (Novak, 1988; Poorbaugh, 1993; Webb, 1993a). These individuals experience itching, stinging/biting, and crawling sensations on or under their skin, which are often associated with excoriations, discoloration, scaling, tunneling or sores. Their conviction that they are infested is reinforced by their observation of particles described as sparkly, crusty, crystal-like, white or black specks and/or fibers.
Typically, these individuals have consulted extensively with general physicians, dermatologists, and entomologists (Kushon et al., 1993) who could not find physical cause for their complaints. Despite findings ruling out lice, scabies or other medical causes, patients refuse to accept the diagnosis of delusory parasitosis (Koblenzer, 1993; Webb, 1993b), become extremely focused on eradicating the pests, and further compromise their skin by frequent scratching, excessive cleaning, and the application of various remedies such as prescription pesticides for lice or scabies, household cleaning products, and organic solvents or fuels. The symptoms are debilitating and the sufferer’s distress is compounded by the lack of a concrete physical diagnosis.