Delusional Parasitosis as 'Folie a Deux'

Abstract

Delusional parasitosis is characterized by the unshakeable belief of being infested with tiny (microscopic) insects. Patients spend much time trying to get rid of the bugs and suffer from these symptoms. Patients prefer to go to dermatologists because they have a strong conviction over the presence of a somatic disease and do not accept any psychiatric advice for their complaints. 'Folie a deux' or shared psychotic disorder (SPD) is a relatively rare syndrome, which has long attracted clinical attention. Delusional parasitosis is associated in 5-15% of SPD and can run within a family. We experienced delusional parasitosis as 'Folie a Deux' between a mother and her son and successfully treated them through early psychiatric intervention. We believe that attention should be drawn to DP with SPD.

Delusional Infestation

“…The first report of an SPD in DI was published in 1923 (111). To date, there are many reports of a folie à deux or a folie à trois, i.e., delusional belief shared by two or three people, respectively, in DI (6,60,97,111,112,115,155,165,192,194,231,250,299,300,308,322,342). There is one report of a folie à cinq (288) and three reports of a folie à famille (53,64,213), i.e., the participation of five family members or all of them.…”

“…In a 72-year-old male with a 5-year history of primary DI which failed to respond to haloperidol decanoate, symptoms started to abate after only 1 week of oral risperidone therapy. Meanwhile, there are well over 30 published cases with risperidone for all forms of DI (3,53,57,68,102,103,141,155,168,172,197,212,213,225,243,244,249,254,258,278,282,341). Since the mid-1990s, further atypical antipsychotics have been licensed for the treatment of schizophrenia, and all of these substances have since been used, with various effects, in cases of primary or secondary DI, including olanzapine (41,89,96,101,141,167,172,199,211,212,249,280), sertindole (348), quetiapine (19,37,76,155,218,249,341), amisulpride (99, 175-177, 212, 253), ziprasidone (99), aripiprazole (141,…”

Successful Treatment of Delusions of Parasitosis With Olanzapine

“…6 In some cases, the delusion is shared by a significant other, and this is termed a folie à deux. 7 Patients may resort to self-mutilation in an effort to rid themselves of parasites, and insomnia is a common complaint. 8 Several steps are useful in approaching patients with DP.…”

Ekbom Syndrome: A Delusional Condition of “Bugs in the Skin”

“…ES patients apply many pesticides, including those not intended for indoor use, spraying insecticides in the home and vehicle as well as on their bodies [3,11,19,31,32]. The resultant dermal damage exacerbates skin irritation, perpetuating the itch-scratch cycle.…”