RESUMO
Granulomatous inflammations are a particular type of chronic septic or aseptic inflammation, in which infectious or non-infectious agents are difficult to eliminate by the immune system. These are type IV hypersensitivity reactions mediated by pre-sensitized T-lymphocytes cells CD4+ and CD8+ lymphocytes. Disorders included in this category are: tuberculosis, leprosy, syphilis, sarcoidosis, type I diabetes, multiple sclerosis, Crohn's disease and rheumatoid arthritis. At cutaneous level, this pattern of granulomatous reaction is characterized by a chronic inflammation with formation of granulomas consisting of a variable number of histiocytes, multinucleated giant cells and lymphocytes. Granulomatous dermatoses should be differentiated from other primary or secondary lesions affecting the skin such as inflammation or tumors. Often granulomatous dermatoses can be confused with other skin disorders, both clinically and histological. Histopathology examination can add important information and clarify the diagnosis. This paper presents a series of three clinical cases of granulomatous skin occurring in the elderly patients confirmed at histology examination. Clinical and histology criteria were analyzed, along with specific differential diagnosis, based on data from the literature.