The eruption pictured in Figure 25 consists of densely arranged erythematous papules, some of them eroded, in wedge-shaped distribution on the upper and the lower part of the back. No blisters are detectable. The differential diagnosis clinically is an unusual expression of dermatitis herpetiformis and linear IgA dermatosis on one hand and a typical manifestation of prurigo pigmentosa at a relatively early stage of it on the other. No mention of the latter possibility was made by the authors, who wrote that particular section in Fitzpatrick's textbook. The distribution of lesions pictured here is uncommon for dermatitis herpetiformis and liner IgA dermatosis, both of those vesicular dermatitides affecting the extremities preferentially, rather than the center of the trunk, as is the case in this patient. No comment at all was made about histopathologic findings. Clinically, the diagnosis is prurigo pigmentosa. Only histopathologic and immunofluorescent findings characteristic of linear IgA dermatosis would convince us that this patient has anything other than prurigo pigmentosa.