ABSTRACT
Psoriasis is a chronic immune-mediated, inflammatory disease mainly involving the skin, nails and joints pathogenetically related to both genetic and environmental factors. The prevalence rate among dark-skinned populations varies according to the countries, yet it is generally lower than that of Caucasians. In hyperkeratotic plaques, thick scales may cover the underlying vascular structures, yet removal of the scales may bring to light the typical vascular pattern. The dermoscopic pattern of specific subtypes of psoriasis do not significantly differ from each other, except for the scaling amount. The most common forms of dermatitis in skin of colour include allergic contact dermatitis and atopic dermatitis, with the latter representing one of the most frequent reasons for referral to a dermatologist in dark-skinned populations. Lichen planus (LP) is an inflammatory mucocutaneous disorder more commonly occurring in middle-aged adults and affecting the skin, mucosae and/or nail that is supposed to be related to an autoimmune response to altered self-antigens on basal keratinocytes.
