Kyrle's Disease in a Patient with Delusions of Parasitosis.

Acquired perforating disorders are a group of uncommon skin conditions characterized by transepidermal extrusion of altered dermal material, most often associated with diabetes mellitus and chronic kidney failure. Delusional parasitosis is a primary psychiatric disorder in which affected patients have fixed, false beliefs that their skin is infested by parasites, in the absence of any evidence supporting their statements. A 69 year old malepatient addressed the Dermatology Department for a skin eruption consisting of multiple umbilicated keratotic papules with a generalized distribution. The patient believed that the lesions were produced by small parasites entering and exiting his skin. The histopathological examination confirmed the clinical diagnosis of Kyrle's disease. The psychiatric examination established the diagnosis of delusions of parasitosis. This is the first reported case of Kyrle's disease associated with delusions of parasitosis. There is no evidence supporting the hypothesis that delusions of parasitosis might be a predisposing factor for Kyrle's disease. However, we believe that the pruritic dermatosis might have triggered the delusions of parasitosis due to the associated pruritus. On the other hand the constant excoriations and traumatizing of a skin prone to develop idiopathic Kyrle's disease in the attempt to remove the parasites prevented the complete resolution of the lesions.

Delusional Infestation and Chronic Pruritus: A Review.

The literature on chronic pruritus, paresthesia and delusional infestation indicates that a wide variety of conditions ranging from AIDS to vitamin deficiencies may cause these symptoms. In many, or perhaps most of these cases, activation of itch pathways seems to be the underlying cause of the skin sensations and perhaps even the visual hallucinations characteristic of delusional infestation. The principle difference between diagnoses of chronic pruritus and delusional infestation appears to lie in the patient's interpretation of the cause of the symptoms, rather than underlying physiological differences. Delusional infestation, paresthesia and chronic pruritus must be considered symptoms of underlying conditions.

Urethral stricture secondary to self-instrumentation due to delusional parasitosis: a case report.

INTRODUCTION: Delusional parasitosis is a rare psychiatric disorder which often presents with dermatological problems. Delusional parasitosis, which involves urethral self-instrumentation and foreign body insertion, is exceptionally rare. This is the first case report to date that provides a detailed presentation of the urological manifestation of delusional parasitosis with complications associated with repeated self-instrumentation and foreign body insertion, resulting in stricture formation and requiring perineal urethrostomy. CASE PRESENTATION: A 45-year-old Irish man was electively admitted for perineal urethrostomy with chronic symptoms of dysuria, haematuria, urethral discharge, and intermittent urinary retention. He reported a 4-year history of intermittent pain, pin-prick biting sensations, and burrowing sensations, and held the belief that his urethra was infested with ticks. He also reported a 2-year history of daily self-instrumentation, mainly injecting an antiseptic using a syringe in an attempt to eliminate the ticks. He was found to have urethral strictures secondary to repeated self-instrumentation. A foreign body was found in his urethra and was removed via cystoscopy. On psychiatric assessment, he displayed a fixed delusion of tick infestation and threatened to surgically remove the tick himself if no intervention was performed. The surgery was postponed due his mental state and he was started on risperidone; he was later transferred to an acute in-patient psychiatric unit. Following a 3-week admission, he reported improvement in his thoughts and distress. CONCLUSIONS: Delusional parasitosis is a rare psychiatric disorder. Self-inflicted urethral foreign bodies in males are rare and have high comorbidity with psychiatric disorders; hence, these patients have a low threshold for referral for psychiatric assessment. The mainstay treatment for delusional parasitosis is second-generation antipsychotic drugs.

Delusional misidentification syndrome and other unusual delusions in advanced Parkinson's disease.

BACKGROUND: Unusual delusional syndromes are rare protean diseases with speculative etiopathogenic mechanisms. METHODS: Seven consecutive patients with advanced PD were evaluated over a 15-year period at the Movement Disorders Unit in the Neurology Service, Hospital de Clínicas, Federal University of Paraná, and the Paraná State Parkinson's Patients Association. RESULTS: We describe advanced Parkinson's disease patients presenting with unusual delusional syndromes, including cases of Ekbom, Othello, Capgras' and Diogenes syndromes, reduplicative paramnesia and mirrored-self misidentification. CONCLUSION: There are a few isolated reports of unusual neuropsychiatric disorders in patients with PD. We believe that these syndromes associated with advanced PD in elderly patients presenting with cognitive impairment and polypharmacy are probably often underestimated. Neurologists should be aware for these rare and treatable conditions.