Delusional parasitosis 240559 226015994 2008-07-16T13:27:33Z Adelpine 7335402 /* External links */ Adding [[es:Delirio de parasitosis]] {{Infobox_Disease | Name = {{PAGENAME}} | Image = | Caption = | DiseasesDB = 9622 | ICD10 = | ICD9 = {{ICD9|300.29}} | ICDO = | OMIM = | MedlinePlus = | eMedicineSubj = derm | eMedicineTopic = 939 | MeshID = }} '''Delusional parasitosis''' also known as '''delusory parasitosis''' and '''delusory cleptoparasitosis''', is a form of [[psychosis]] or false belief, a "loss of contact with reality". In delusional parasitosis, sufferers have a strong [[delusion]]al belief that they are infested with [[parasite]]s, whereas in reality no such parasites are present.<ref name="Webb">{{cite journal | author = Webb, J. P., Jr. | year = 1993 | title = Case histories of individuals with delusions of parasitosis in southern California and a proposed protocol for initiating effective medical assistance | journal = Bulletin of the Society of Vector Ecologists | volume = 18 | issue = 1 | pages = 16–24 }}</ref> Very often the imaginary parasites are reported as being "bugs" crawling on or under the skin; in these cases the experience of the sensation known as [[formication]] may be the basis for this belief. Delusional parasitosis is also referred to as '''Ekbom's syndrome''', named after a Swedish neurologist, [[Karl Axel Ekbom]],<ref>{{WhoNamedIt|synd|2338|Ekbom's syndrome II}}</ref> who published seminal accounts of the disease in [[1937]] and [[1938]]. Ekbom's syndrome should not be confused with [[Wittmaack-Ekbom syndrome]], which is another name for restless legs syndrome. The false belief of delusional parasitosis stands in contrast to actual cases of parasitosis, such as for example, [[scabies]]. People with delusional parasitosis are likely to ask for help not from psychiatrists but from [[dermatologist]]s, pest control specialists, or [[entomology|entomologists]]. Because delusional parasitosis is not at all well known to non-specialists, under those circumstances the condition often goes undiagnosed, or may be incorrectly diagnosed. ==Classification== Delusional parasitosis is divided into primary, secondary functional and secondary organic groups.<ref name=Freinhar1984>{{cite journal | author = Freinhar, Jack P. | year = 1984 | title = Delusions of parasitosis | journal = Psychosomatics | volume = 25 | issue = 1 | pages = 47–53 }}</ref> ===Primary=== In primary delusional parasitosis, the delusions comprise the entire disease entity, there is no additional deterioration of basic mental functioning or idiosyncratic thought processes. The parasitic delusions consist of a single delusional belief regarding some aspect of health. This is also referred to as monosymptomatic hypochondriacal psychosis, and sometimes as "true" delusional parasitosis. In DSM-IV, this corresponds with "delusional disorder, somatic type". ===Secondary functional=== Secondary functional delusional parasitosis occurs when the delusions are associated with a psychiatric condition such as [[schizophrenia]] or [[clinical depression]]. ===Secondary organic=== Secondary organic delusional parasitosis occurs when the state of the patient is caused by a medical illness, medication or substance abuse. In DSM-IV this corresponds with "psychotic disorder due to general medical condition." Physical illnesses that can underly Secondary organic delusional parasitosis include: [[hypothyroidism]], [[cancer]], [[cerebrovascular disease]], [[tuberculosis]], [[neurological disorders]], [[vitamin B12 deficiency]], and [[diabetes mellitus]]. Any illness of medication of which formication is a symptom or side effect can become a trigger or underlying cause of delusional parasitosis. Other physiological factors which can contribute to the condition include: menopause (i.e. hormone withdrawal); allergies; drug abuse, including but not limited to [[cocaine]] and [[methamphetamine]] (as in [[amphetamine psychosis]]); certain medical conditions; and poor nutrition.<ref name = Hinkle/> It appears that many of these physiological factors, as well as environmental factors such as airborne irritants, are capable of inducing a "crawling" sensation in otherwise healthy individuals, however some people become fixated on the sensation and its possible meaning, and this fixation may then develop into delusional parasitosis.<ref name = Hinkle/> ==Presentation== Details of delusional parasitosis vary among sufferers, but is most commonly described as involving perceived parasites crawling upon or burrowing into the skin, sometimes accompanied by an actual physical sensation (known as [[formication]]).<ref name = Webb/> Individuals suffering from this condition may injure themselves in attempts to be rid of the "parasites", and sometimes are able to induce the condition in others through [[suggestion]] (a phenomenon dubbed ''[[folie à deux]]'').<ref name="Koblenzer">{{cite journal | author = Koblenzer, C. S.. | year = 1993 | title = The clinical presentation, diagnosis and treatment of delusions of parasitosis--a dermatologic perspective | journal = Bulletin of the Society of Vector Ecologists | volume = 18 | issue = 1 | pages = 6–10 }}</ref> Nearly any marking upon the skin, or small object or particle found on the person or their clothing, can be interpreted as evidence for the parasitic infestation, and sufferers commonly compulsively gather such "evidence" and then present it to medical professionals when seeking help.<ref name = Webb/> This presenting of "evidence" is known as "the matchbox sign". Delusional parasitosis is seen more commonly in women, and the frequency is much higher past the age of 40.<ref name="Hinkle">{{cite journal | last =Hinkle | first =Nancy C. | title =Delusory Parasitosis | journal =American Entomologist | volume =46(1) | pages =17–25 | date = 2000 | url =http://www.mental.health.wa.gov.au/one/resource/41/delusory%20parasitosis%20Dr%20N%20Hinkle.pdf | doi = }}</ref> ==Treatment== Treatment of secondary forms of delusional parasitosis are addressed by treating the primary associated psychological or physical condition. The primary form is treated much as other [[delusional disorder]]s and [[schizophrenia]]. In the past, [[pimozide]] was the drug of choice when selecting from the [[typical antipsychotic]]s. Currently, [[atypical antipsychotic]]s such as [[olanzapine]] or [[risperidone]] are used as first line treatment. However, it is also characteristic that sufferers will reject the diagnosis of delusional parasitosis by medical professionals, and very few are willing to be treated, despite demonstrable efficacy of treatment.<ref name = Webb/> ==Morgellons== The term "[[Morgellons]]" was introduced in 2004 to describe a skin condition characterized by lesions and fibers on and under the skin and certain systemic symptoms. A majority of health professionals, including most dermatologists, regard Morgellons as a manifestation of other known medical conditions, including delusional parasitosis<ref name="nature">[http://www.nature.com/nm/journal/v12/n9/full/nm0906-982a.html Mysterious 'Morgellons disease' prompts US investigation], Emma Marris, Nature Medicine, [[30 August]] [[2006]]</ref><ref name="Scheinfeld">[http://www.emedicine.com/derm/topic939.htm Delusions of Parasitosis] Noah Scheinfeld, [[May 4]], [[2007]]</ref><ref name="AJP">{{cite journal | last =Dunn | first =Jeffrey | coauthors =Michael B. Murphy and Katherine M. Fox | title =Diffuse Pruritic Lesions in a 37-Year-Old Man After Sleeping in an Abandoned Building | journal =The American Journal of Psychiatry | volume =164 | pages =1166–1172 | date = August, 2007 | url =http://ajp.psychiatryonline.org/cgi/content/full/164/8/1166 | doi =10.1176/appi.ajp.2007.07030381 | accessdate = 2007-08-04 | pmid =17671278 }}</ref> and believe any fibers found are from textiles such as clothing.<ref>{{Cite news|title=All in the head?|author=Elaine Monaghan|publisher=The Times|date=[[May 19]], [[2006]]|accessdate=2007-08-14|url=http://www.timesonline.co.uk/tol/comment/article721795.ece}}</ref> The [[Morgellons Research Foundation]], a non-profit advocacy organization, believes that it is a new infectious disease that will be confirmed by future research.<ref name="mrf">[http://www.morgellons.org/ Morgellons.org]</ref><ref name="AJCD">Savely VR, Leitao MM, and Stricker, RB. The mystery of Morgellons disease: infection or delusion? Am J Clin Dermatol. 2006;7(1):1–5 PMID 16489838</ref> "Other health professionals don't acknowledge Morgellons disease or are reserving judgment until more is known about the condition."<ref name="mayo">{{cite web | url=http://www.mayoclinic.com/health/morgellons-disease/SN00043 | title=Morgellons disease: Managing a mysterious skin condition | publisher=[[Mayo Clinic]] | date=2007-05-02 | accessdate=2007-08-04}}</ref> Research into the proposed condition is ongoing. ==References== {{Reflist|2}} ==External links== * {{cite journal | author = Ekbom K, Yorston G, Miesch M, Pleasance S, Rubbert S | title = The pre-senile delusion of infestation | journal = Hist Psychiatry | volume = 14 | issue = 54 Pt 2 | pages = 229–56 | year = 2003 | pmid = 14521159 | doi = 10.1177/0957154X030142007}} *[http://delusion.ucdavis.edu/delusional.html The Bohart Museum of Entomology; Human Skin Parasites & Delusional Parasitosis] *[http://psy.psychiatryonline.org/cgi/content/full/39/6/491 Psychogenic Parasitosis] Slaughter, James R., et al, Psychosomatics 39:491-500, December 1998 [[Category:Psychiatry]] [[Category:Psychosis]] [[Category:Symptoms]] [[de:Dermatozoenwahn]] [[es:Delirio de parasitosis]] [[fr:Syndrome d'Ekbom]]