In acute inflammation the tissue response consists of all except
Ref Robbins9/e p97 Granulomatous inflammation is a distinctive pattern of chronic inflammation characterized by aggregates of acti- vated macrophages with scattered lymphocytes. Granulo- mas are characteristic of ceain specific pathologic states; consequently, recognition of the granulomatous pattern is impoant because of the limited number of conditions (some life-threatening) that cause it (Table 2-8). Granulo- mas can form under three settings: * With persistent T-cell responses to ceain microbes (such as Mycobacterium tuberculosis, T. pallidum, or fungi), in which T cell-derived cytokines are responsible for chronic macrophage activation. Tuberculosis is the proto- type of a granulomatous disease caused by infection and should always be excluded as the cause when granulomas are identified. * Granulomas may also develop in some immune- mediated inflammatory diseases, notably Crohn disease, which is one type of inflammatory bowel disease and an impoant cause of granulomatous inflammation in the United States. * They are also seen in a disease of unknown etiology called sarcoidosis, and they develop in response to rela- tively ine foreign bodies (e.g., suture or splinter), forming so-called foreign body granulomas.
Vasodilation
Exudation
Neutrophilic response
Granuloma formation
General anatomy