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.