Pathology of Inflammation (cont.) PDF

Pathology of Inflammation (cont.) By Prof. Mie Ali Prof. Mona Younis Pathology department Faculty of Medicine – Mansoura University & HUE Fate of acute inflammation  1) Regression: If the body res...

Pathology of Inflammation (cont.) By Prof. Mie Ali Prof. Mona Younis Pathology department Faculty of Medicine – Mansoura University & HUE Fate of acute inflammation  1) Regression: If the body resistance overcomes the irritant; inflammation may show repair either by: a- Resolution: If no tissue damage occurred, the tissue returns completely to normal. b- Fibrosis: If tissue damage occurred.  2) Progression & spread of infection: If the irritant overcomes the body defense → spread of infection by:- 1. Direct to the surrounding tissues by fluid exudate. 2. Phagocytosis if the organisms are still living inside the phagocytic cells. 3. Blood spread → the infections and/or its toxins reach the blood. 4. Lymphatic spread → lymphangitis “inflammation of lymphatic vessels” and lymphadenitis “inflammation of lymph nodes”.  3) Chronicity:- The defense mechanism weakens the irritant but is not completely eliminated. Chronic inflammation  Chronic inflammation Definition: It is a type of inflammation in which lymphocytes, plasma cells, macrophages & giant cells predominate. It is accompanied with fibrosis (as an evidence of repair) and End Arteritis Oblitrans (EAO).  Types of chronic inflammation: (1) Chronic non-specific (2) Chronic specific inflammation inflammation:- "Granulma":- - Follow acute inflammation. - Chronic from the start. - It is "non-specific" because many - Each irritant produce specific lesion irritants produce the same lesion and the irritant could be detected (chronic inflammatory cells, fibrosis within the lesion and EAO) irrespective of the cause e.g. Bilharzial ova in cases of which couldn't be identified. Bilharziasis.  Granulomas * Definition: Chronic specific inflammation in which the macrophages play a predominant role. * NE: It starts as tiny granules which fuse to form large mass. * ME: ** Its shape is characteristic for each irritant (specific) that may be seen inside the granuloma. ** Macrophages, Lymphocytes and giant cells are the main cells of a granuloma. ** It is surrounded by fibrosis.  Types (etiology) of granulomas * Types: (1) Infective granuloma: a. Bacteria (T.B, Syphilis) b. Parasite (Bilharziasis) c. Virus (lymphogranuloma inguinale) d. Fungi (Actinomycosis) (2) Non infective granuloma: a. Allergic granuloma: as Rheumatic fever. b. Foreign body granuloma: due to foreign material in the tissues e.g. surgical sutures.