Inflammation Pathophysiology PDF

Pathophysiology Lab 2  Inflammation: is a response of living tissues to a harmful insult or agents. Its purpose is to localize, eliminate the injurious agent, remove damaged tissue and replace it with healthy new tissue (repair). Terms ending in the suffix “–itis” denote inflammation Examp...

Pathophysiology Lab 2  Inflammation: is a response of living tissues to a harmful insult or agents. Its purpose is to localize, eliminate the injurious agent, remove damaged tissue and replace it with healthy new tissue (repair). Terms ending in the suffix “–itis” denote inflammation Examples: Appendix appendicitis Larynx laryngitis Bronchi bronchitis Gastric mucosa gastritis Hair follicle folliculitis But it not always Can be considered:  Lung tissue pneumonia Breast mastitis Joint arthritis It consists principally of: 1-Vascular changes : 2-Leukocyte infiltration and: 3-Systemic reaction.  Causes of inflammation 1) Infection: Bacterial ,Viral, Parasitic and microbial toxins 2) Immunological: hypersensetivity reactions and autoimmune diseases 3) Physical agents: trauma, radiation, burn 4) Chemical agents: strong acids and alkalines, toxins 5) Foreign bodies: splinters, sutures and dirts 6) Circulation disorders: thrombosis, hemorrhage  Types of inflammation: Acute inflammation (sec, mins, hrs or days) Chronic inflammation (weeks, months, years)  Acute inflammation An inflammatory response that : I. Lasts only for short period. II. Characterized by the exudation of fluid and plasma protiens III. Emigration of leukocytes predominantly neutrophiles. The five Cardinal Signs of Acute Inflammation  Heat (CALOR)  Redness (RUBOR)  Swelling (TUMOR)  Pain (dolor)  Loss of function (FUNCTIO LAESA) Morphological types of acute inflammation 1- Serous type: The fluid exudate resumble serum or is watery ex. Skin blisters from burns or viral infection 2- Fibrinous type: It is characterized by a thick exudate containing fibrin usually found in serous cavities as pericardium 3- Suppurative type: It is characterized by production of pus containing neutrophils, liquified cellular debris and edema fluid ex. Pyogenic bacterial infection. It may lead to abscess formation Abscess 4- Acute catarrhal type: It is inflammation of mucous membranes, characterized by mucus secretion, as in infections ex. Runny nose in common cold, gastritis, colitis mucin  5- Acute hemorrhagic: It is characterized by microvascular injury with massive microvascular bleeding producing an exudate with a high erythrocyte content The inflammed area is necrotic and filled with blood 6- Pseudomembranous type: Bacterial toxins damage mucosal lining producing a membrane composed of necrotic tissue ex. Corynebacterium diphtheriae produce pseudomembrane in the pharynx and trachea Pseudomembranous colitis Diphtheria Out come of acute inflammation Chronic Inflammation Chronic inflammation is defined as prolonged process in which tissue destruction, inflammation and attempt to repair occur at the same time. Chronic inflammation can be caused by one of the following 3 ways: 1. Progression of acute inflammation e.g. osteomyelitis 2. Recurrent attacks of acute inflammation lead to chronicity e.g. in recurrent urinary tract infection leading to chronic pyelonephritis, repeated acute infection of gallbladder leading to chronic cholecystitis. 3. Chronic inflammation starting de novo: i. Infection: Tuberculosis. TB. Leprosy, Syphilis ii. Foreign body : surgical sutures iii. Hypersensitivity reactions (HSR): Systemic Lupus Erythematous (SLE), Rheumatoid Arthritis (RA) Systemic Effect of Chronic Inflammation Mild Fever, loss of weight and weakness Anemia Leukocytosis Elevated ESR  TYPES OF CHRONIC INFLAMMATION Chronic inflammation is subdivided into 2 types: 1. Chronic non-specific inflammation. It is characterized by chronic inflammatory cell infiltration e.g. chronic osteomyelitis, lung abscess. 2. Chronic granulomatous inflammation. It is characterized by formation of granulomas e.g. tuberculosis, foreign body  Acute vs chronic cholecystitis (chronic non specific) Chronic Acute Wall is penetrated by mucosal Neutrophils infiltrating mucosa glands with inflammatory cells and submucosa infiltration and fibrosis  Chronic non specific inflammatory bowel disease Chronic Granulamatous Types of multinucleated giant cells: Foreign body multinucleated giant cell/ foreign body Langhans multinucleated giant cell/ TB Touton multinucleated giant cell/ tumour Q/ Identify the type of giant cell?  Composition of Granuloma A granuloma has the following structural composition: 1. Necrosis. Necrosis may be a feature of some granulomatous conditions e.g. central caseation necrosis of tuberculosis 2. Epithelioid cells which are modified macrophages 3. Multinucleate giant cells. Multinucleate giant cells are formed by fusion of adjacent epithelioid cells and may have 20 or more nuclei. These nuclei may be arranged at the periphery like horseshoe or ring, or are clustered at the two poles (Langhans’ giant cells), or they may be present centrally (foreign body giant cells). The former are commonly seen in tuberculosis while the latter are common in foreign body tissue reactions. 4. Lymphocytes 5. Fibrosis. Fibrosis is a feature of healing by proliferating fibroblasts at the periphery of granuloma.  The classical example of granulomatous inflammation is the tissue response to tubercle bacilli which is called tubercle seen in tuberculosis. A fully-developed granuloma is about 1 mm in diameter with central area of caseaous necrosis, surrounded by epithelioid cells and one to several multinucleated giant cells (commonly Langhans type), surrounded at the periphery by lymphocytes and bounded by fibroblasts and fibrous tissue