Auspitz sign is not sensitive or specific for psoriasis.

The Auspitz sign refers to the appearance of small bleeding points after successive layers of scale have been removed from the surface of psoriatic papules or plaques. In this study the Auspitz sign was present in only 41 of 234 patients with psoriasis. Furthermore, small bleeding points could be produced when scale was forcibly removed from several nonpsoriatic, scaling disorders, including Darier's disease and actinic keratoses. The frequent absence of the Auspitz sign in psoriasis indicates a lack of sensitivity, whereas its occurrence in other diseases indicates a lack of specificity.