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Collembola
Implicated in Delusory Parasitosis
Laurie
Barclay, MD
Aug. 2, 2004 — The arthropod
Collembola
(Springtails) is a common factor in patients originally diagnosed with
delusory parasitosis, according to the results of a case-controlled
study published in the June issue of the
Journal of
the New York Entomological Society.
"Delusory parasitosis...is a presumed
psychiatric condition ascribed to individuals who are convinced, in
the absence of any empirical evidence, that they are infected with an
insect or parasite," write Deborah Z. Altschuler, from the National
Pediculosis Association (NPA), in Needham, Massachusetts, and
colleagues. "The symptoms are debilitating and the sufferer's distress
is compounded by the lack of a concrete physical diagnosis."
In this single-site clinical study
conducted by the NPA and the Oklahoma State Department of Health,
multiple skin scrapings from each of 20 individuals diagnosed with
delusory parasitosis were examined microscopically. The subjects were
part of a larger group of more than 1,500 persons reporting symptoms
of stinging, biting, and/or crawling to the NPA, and their symptoms
were originally attributed to lice or scabies.
There were more than 300 anomalous
findings in skin scrapings from the 20 subjects and none in the
controls. These anomalies included pollen, spores, hyphae, mycelium,
algae, and what appeared to be insect eggs, larvae, or embryos.
Although digital photography of any and all fields of view that
appeared incongruous to normal human skin initially revealed no common
factor, more extensive examination using imaging software revealed
evidence of
Collembola in 18 of the 20 subjects.
The authors note that
Collembola are
abundant in wastewater and contaminated environments with high
humidity and abundant organic debris.
"It is possible
Collembola
found in lesions are opportunistic and that fungal infections or
allergic reactions to pollen, fungi, spores or other organisms may
contribute to or be responsible for the symptoms these individuals
experience," the authors write. "Collembola
do not need to be human parasites in order to be present in the skin
scrapings."
The NPA encourages medical
professionals, sufferers or anyone
with information on these or similar symptoms to share
information
by visiting the NPA's
Reporting Registry. |
J New
York Entomol Soc. 2004;112:87-95
Reviewed by Gary D. Vogin, MD
Laurie
Barclay, MD
Freelance writer for Medscape Medical News.
Medscape Medical News is edited by Deborah Flapan, assistant
managing editor of news at Medscape.
Medscape Medical News
2004
© 2004 Medscape
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J. New York Entomol.
Soc. 112(1):87–95, 2004 4
COLLEMBOLA
(SPRINGTAILS) (ARTHROPODA: HEXAPODA: ENTOGNATHA) FOUND IN SCRAPINGS
FROM INDIVIDUALS DIAGNOSED WITH DELUSORY PARASITOSIS DEBORAH Z.
ALTSCHULER,1 MICHAEL CRUTCHER, MD, MPH, FACPM,2 NECULAI DULCEANU, DVM,
PHD (DECEASED),3 BETH A. CERVANTES,1 CRISTINA TERINTE, MD, PHD4 AND
LOUIS N. SORKIN, BCE5 1National Pediculosis Association, 50 Kearney
Road, Needham, Massachusetts 02494; 2 3 Commissioner of Health,
Oklahoma State Department of Health, 1000 NE 10th Street, Oklahoma
City, Oklahoma 73117; Department of Parasitology, University of
Veterinary Medicine, Iasi, Romania; Department of Pathology,
University of Medicine and Pharmacy, Iasi, Romania; and 5Division of
Invertebrate Zoology, American Museum of Natural History, Central Park
West at 79th Street, New York, New York 10024-5192 Abstract.—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. Key words:
Collembola,
springtail, stinging, biting, crawling, Arthropoda, Hexapoda,
Entognatha, pediculosis, human skin, lice and scabies. 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. Vol. 112(1) JOURNAL OF THE
NEW YORK ENTOMOLOGICAL SOCIETY 88 Hundreds of sufferers have reported
symptoms to the National Pediculosis Association (NPA), as well as to
the Oklahoma State Department of Health, similar to those described by
Traver in reporting her own infestation (Traver, 1951). In response to
the compelling nature of these reports, the NPA agreed to conduct a
controlled research study of skin specimens in cooperation with the
Oklahoma State Health Department. Twenty individuals diagnosed as
having delusory parasitosis and ten non-symptomatic controls
volunteered to participate in this effort. The clinical portion of the
study was conducted at a single site during three weeks. Doctors with
experience in the skin scraping method of specimen collection obtained
and microscopically examined samples, and all anomalous findings were
photographed. Procedures were instituted to preclude contamination,
such as reported by Poorbaugh (1993). STUDY DESIGN Study Locale. The
clinical portion of this study was conducted at the Oklahoma State
Department of Health, Oklahoma City, Oklahoma between June 28 and July
20, 2000. Study Participants. Twenty symptomatic participants were
selected from the hundreds of individuals who had previously contacted
the NPA regarding an unknown condition possibly associated with lice
and/or scabies but for which these parasites had been ruled out. Their
physicians subsequently diagnosed them as suffering from delusory
parasitosis. These volunteers were accepted on the basis of their
willingness to travel to Oklahoma City at their own expense, complete
questionnaires regarding their symptoms and medical history, and
submit to multiple skin scrapings. Ten controls, randomly selected
from employees of the Oklahoma State Health Department, were also
enrolled. All participants signed a waiver of liability and understood
that this was an initial research effort. Intake Evaluations. Intake
consisted of having symptomatic participants complete a
selfadministered questionnaire that was similar in content to the
‘‘not-lice’’ survey posted on the NPA website (www.headlice.org). Body
diagrams of ventral and dorsal surfaces were marked to identify common
areas of lesions. Two participants had symptoms without lesions or
dermatitis at the time of the trial. Specimen Preparation. Trained
personnel prepared all skin scrapings. Prior and subsequent to
scraping the skin with a disposable scalpel, symptomatic areas and
areas at or around lesions were cleansed with gauze and alcohol.
Immediately after being obtained, the scraped material was transferred
to a fresh microscope slide with a drop of sterile water, coverslipped
and isolated. Between 15 and 35 slides were prepared and examined for
each subject. Scrapings were obtained from non-symptomatic controls
from regions of the body where most lesions were noted on symptomatic
participants. Specimen Photography and Data Tracking. All slides were
viewed using an Olympus BX60 Dual Viewing Microscope. The images that
appeared incongruent with normal healthy skin were photographed using
a SPOT RGB digital camera and SPOT software version 3.0. Each image
was assigned a unique identifier and the magnification of the image
was recorded. Images were sized by comparison with images of a B&L
micrometer with marks for 0.1 mm and 0.01 mm that were taken at 1003,
2003 and 4003 magnification with the same camera and software used in
the clinical study. Initial microscopy was non-blinded; i.e., the
clinicians examining and photographing the slides knew that they were
from either the study participant or control group. 89 SPRINGTAILS AND
DELUSORY PARASITOSIS (COLLEMBOLA)
2004 RESULTS Over 300 microscopic fields from study participants who
complained of stinging/biting and/ or crawling sensations in their
skin appeared incongruent with normal skin and therefore were
photographed for later scrutiny. Pollen, conidia or spores, hyphae,
mycelium or fibers, or what appeared to be clumped skin or cellular
debris were identified during the first six months of image analysis.
One or two-cell algae, nematodes, or what appeared to be insect eggs,
larvae or embryos were also identified. Although everyone in the group
had at least one of the above findings, none of the findings were a
common factor in every subject, making it necessary to continue
looking for a common denominator. Because
Collembola had
been reported from individuals experiencing these symptoms (Dasgupta
and Dasgupta, 1995; Frye, 1997; Scott et al., 1962), they became the
focus of subsequent image analysis. Identification of
Collembola in
scrapings from symptomatic study participants required intensive
scrutiny of the photographs and was initially very difficult. Most
Collembola were
enmeshed in accumulations of exuviae. Eggs ranged from 20 to 100
microns in diameter. The size of most
Collembola
noted was 50–300 microns in length, suggesting a predominance of
nymphs as opposed to adults. To ensure reliability of results,
researchers verified at least two sightings before a subject was
considered to have positive
Collembola
findings. However, scrapings from 10 of the subjects showed an
abundance of
Collembola. Evidence of
Collembola was
found in images of scrapings from 18 of the 20 individuals that had
been diagnosed as delusional. Of the two participants without lesions
or dermatitis at the time of the trial, one had images positive for
Collembola.
Examples of some of these findings and the photographic fields in
which they appeared are provided in Fig. 1–3. Each image was obtained
from a different study participant. Fig. 1: Photomicrograph of debris
that demonstrated at higher magnification the presence of
Collembola. Two
examples are highlighted and enlarged in Fig. 1a. Fig. 2: A clearly
recognizable
Collembola (approximately 100 microns in length) is resting on top
of the debris in the lower right. Fig. 3: Provides an example of
Collembola
enmeshed in debris.
Collembola were present in ninety percent of the study
participants who complained of stinging/biting and/or crawling
sensations on or under their skin. Microscopic examination of
scrapings of control subjects appeared to be consistent with normal
skin and therefore no photographic images were taken. More than 1,500
individuals registered with the NPA (data on file) as having
stinging/biting and/or crawling sensations that they initially
attributed to lice and/or scabies. Approximately half of these
individuals described three or more abnormalities in skin appearance
and observed two or more different types of skin particles. The
demographics and symptoms of these individuals and the study
participants were compared (see Table 1). DISCUSSION The findings of
Collembola in
images of scrapings from 18 of the 20 symptomatic study participants
supports their contention that they actually have something crawling
on or under their skin and are not delusional. The images were
reviewed by entomologists and the presence of
Collembola
verified and identified as representative of the families Isotomidae
and Entomobryidae. Vol. 112(1) JOURNAL OF THE NEW YORK ENTOMOLOGICAL
SOCIETY 90 Fig. 1. Debris that demonstrated at higher magnification
the presence of
Collembola. 91 SPRINGTAILS AND DELUSORY PARASITOSIS (COLLEMBOLA)
2004 Fig. 2.
Collembola in debris in lower right. The study was designed to
minimize any possibility of sample contamination in the skin
scrapings. All scrapings were done at a single site by clinicians
skilled in the skin scraping method of collection. Microscopic
evaluation of skin scrapings from the ten non-symptomatic controls
showed nothing incongruous with normal skin and were therefore not
photographed. This supports the contention that the methodology
employed adequately protected against sample contamination during
collection. A ‘‘classic’’ report of arthropod infestation was reported
by Traver (1951) in which the author described an infestation by a
mite species on her person. Traver (1951) has been referenced by
various authors who gave validity to her infestation. Subsequently,
papers were presented during the Symposium: Delusions of Parasitosis.
18 November 1991 refuting her findings and attributing them to
equipment contamination. The mite was identified by Fain (1967) as the
common house dust mite Dermatophagoides pteronyssus. The directive to
photograph all images associated with abnormal skin was critical to
identifying
Collembola in the skin scrapings. The fields contained fungal
mycelium, or what appeared at first glance to be cellular clumps or
debris. The
Collembola were extremely well hidden in the exuviae and therefore
easy to miss. It was only after intense scrutiny that they were
recognized. In addition, because the
Collembola were
not always intact or completely in focus, they were difficult to
discern. Given these challenges, it is easy to appreciate why there
have been only a few previous reports of
Collembola in
human skin. Vol. 112(1) JOURNAL OF THE NEW YORK ENTOMOLOGICAL SOCIETY
92 Fig. 3.
Collembola enmeshed in debris.
Collembola were
identified in skin scrapings submitted to the Entomology Branch of the
National Center for Infectious Diseases in 1995 (pers. comm.) by an
oncology nurse diagnosed as having delusory parasitosis. Subsequently,
there have been additional reports that provided evidence of
Collembola in
skin from one or more individuals diagnosed with similar symptoms
(Dasgupta and Dasgupta, 1995; Frye, 1997). Because the samples were
self-collected and contained a number of other anomalies, including
fungi spores and filaments, foreign fibers, plus an assortment of
‘‘organisms,’’ the finding of
Collembola was
regarded as intentional or unintentional sample contamination. In the
current study, in which pains were taken to avoid sample
contamination, there were over 300 anomalous findings in skin
scrapings from the 20 symptomatic study participants and none from
controls. These findings included pollen, conidia or spores, hyphae,
mycelium, algae or fibers, clumped skin or cellular debris, an
occasional nematode, and what appeared to be insect eggs, larvae or
embryos. These collective anomalies point to the compromised skin of
most of the symptomatic study participants, and could directly or
indirectly (through an immune or allergic response) produce sensations
of stinging/biting and/or crawling, as well as some of the other
symptoms.
Collembola are abundant in wastewater and contaminated
environments making them of growing ecotoxicologic importance (Hopkin,
1997). Generally, they feed on decaying matter, SPRINGTAILS AND
DELUSORY PARASITOSIS (COLLEMBOLA)
2004 Table 1. Reporting Registry Data QTY Symptomatic Study
Participants n ¼ 20 % Background 3 17 2 11 7 0 0 9 2 8 1 0 10 10 20 18
16 Sex male female Age 66 or over between 41 and 65 between 26 and 40
25 or under unknown General health before onset of symptoms excellent
very good good fair poor Others with condition in household outside
household Treatment attempts over the counter prescription home-remedy
Specific abnormalities lumps on head, scalp hair breaking off eyes
watery, itchy genital symptoms 16 13 13 12 Description of symptoms 18
20 16 Skin sensation crawling stinging/biting itching Skin findings
crystals sparkly particles crusty particles sticky particles white
specks black specks fibers hair, dust one or more of above 17 15 15 10
15 18 18 16 20 15% 85% 10% 55% 35% 0% 0% 45% 10% 40% 5% 0% 50% 50%
100% 90% 80% 80% 65% 65% 60% 90% 100% 80% 85% 75% 75% 50% 75% 90% 90%
80% 100% 93 Larger Symptomatic Population n ¼ 1681 % QTY 29% 71% 491
1,190 2% 23% 48% 23% 3% 42 394 804 391 50 45% 30% 18% 5% 2% 751 510
300 90 30 43% 33% 715 562 31% 29% 18% 526 484 296 43% 27% 33% 38% 720
458 559 632 83% 79% 94% 1,393 1,327 1,574 30% 25% 31% 19% 36% 36% 29%
26% 66% 511 423 529 314 602 600 485 441 1,116 JOURNAL OF THE NEW YORK
ENTOMOLOGICAL SOCIETY 94 Table 1. Continued. two or more of above
three or more of above Skin appearance sores rash scaling
discoloration scarring tracks one or more of above two or more of
above three or more of above algae, fungi and bacteria. In fact, a
fungal infection appears to be a prerequisite condition before
collembolans can gain access into the abdominal cavities of cabbage
maggot flies Delia radicum (Griffiths, 1985). Some species of
Collembola are
known plant and mushroom pests and one species has been taken from
dried milk powder (Scott, 1996). Typical collembolan habitats are
moist environments with high humidity and abundant organic debris.
These conditions are present in the lesions in symptomatic study
participants; it is possible
Collembola
found in lesions are opportunistic and that fungal infections or
allergic reactions to pollen, fungi, spores or other organisms may
contribute to or be responsible for the symptoms these individuals
experience.
Collembola do not need to be human parasites in order to be
present in the skin scrapings. Photographs were taken of all scrapings
showing anything inconsistent with normal skin. After identifying
these anomalies as pollen, spores, etc., more extensive scrutiny
revealed the presence of
Collembola.
Since it was the pollen, spores, hyphae, fiber and other
microorganisms that prompted the photography, it is not known if
Collembola
(without any pollen, spores, etc.) could have been present in the
control group. The population studied in this trial was a subset of
over 1,500 individuals registered with the NPA as experiencing
crawling and/or biting/stinging sensations in the absence of lice or
scabies. This general population shares many of the characteristics of
those who participated in the study. Although the questionnaire
utilized was self-administered and had its limitations, it is
reasonable to postulate that a percentage of this more general
population may very well have similar findings to the 20 symptomatic
individuals who participated in this study. More research is required
before the true prevalence and importance of
Collembola in
humans can be ascertained. The authors would like to acknowledge
Ferris J. Barger for his help with microphotography and Dr. BethAnn
Friedman and Jane Cotter for manuscript preparation. QTY Symptomatic
Study Participants n ¼ 20 % 100% 95% 20 19 90% 60% 80% 75% 80% 80% 95%
95% 95% 18 12 16 15 16 16 19 19 19 ACKNOWLEDGMENTS Vol. 112(1) Larger
Symptomatic Population n ¼ 1681 % QTY 48% 36% 802 604 59% 51% 38% 32%
40% 35% 83% 64% 46% 990 856 639 541 668 585 1,398 1,084 772 95
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2004 LITERATURE CITED Dasgupta, R. and B. Dasgupta. 1995. A treatise
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