In terms of skin examinations, pruritus can present in different ways to clinicians. It can present on normal skin (IFSI classification group II) or together with dermatoses (IFSI classification group I) including dry skin (xerosis), a common cause of pruritus. Sometimes, the presentation of pruritus involves chronic scratch lesions (IFSI classification group III) such as lichen simplex chronicus prurigo nodularis. Localized pruritus, a component of dysesthesia, is often observed in neurologic and neuropathic disorders. The clinical presentation may, however, not reveal much about the etiology of the pruritus, as even dermatological diseases can present with itch on (almost) normal skin.
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