Pityriasis alba is characterized clinically by few to many subtly ("furfuraceous") scaly hypopigmented macules and patches situated especially on the face and, at times, on the arms or trunk of children usually. The findings histopathologically are a sparse superficial perivascular infiltrate of lymphocytes, very slight spongiosis focally in company with but a few lymphocytes, and, sometimes, a tad of parakeratosis. The papillary dermis is devoid of alteration of collagen bundles.

Vitiligo consists of depigmented macules and patches in localized, segmental, or widespread fashion, the absence of pigment tending to be symmetrical and the predilection for lesions being the face and distal extremities. The condition usually begins in young persons and has a protracted course; repigmentation may occur in some individuals. There are no scales. In an "early" lesion of vitiligo, lymphocytes are present around venules of the superficial plexus and a few are sprinkled in the lower half of the epidermis in company with sparse spongiosis. The number of melanocytes at the dermo-epidermal junction of an "early" lesion is normal; only in a fully developed lesion of vitiligo can a decrease in the number of melanocytes and in the amount of epidermal melanin be appreciated. Late in the course, there are no lymphocytes and no melanocytes, and there is no melanin.