ABSTRACT
Sarcoidosis is a systemic granulomatous condition of unknown aetiology that is histologically typified by noncaseating, “naked” granulomas. Cutaneous manifestations of sarcoidosis are divided into non-specific/reactive and specific lesions. The dermoscopic hallmark of the various forms of sarcoidosis classically consists of the presence of orange structureless areas histologically corresponding to the dense and compact granulomatous infiltrate in the dermis. Necrobiosis lipoidica (NL) is an uncommon chronic idiopathic granulomatous disorder characterized by necrobiotic degenerative changes of dermal collagen that mainly affects young and middle-aged adults with a female sex predominance. Granuloma annulare is a relatively frequent, benign, inflammatory condition of uncertain aetiology that may show several histological patterns, including “interstitial”, “palisading granuloma”, sarcoidosis-like and mixed, with the first two forms being by far the most common. Lupus miliaris disseminatus faciei (LMDF), also known as acne agminata, is a relatively rare granulomatous dermatosis that is thought to be an inflammatory reaction to destroyed hair follicles.
