Cardinal Signs of Inflammation - Pain - Heat - Redness - Swelling - Loss of function

Duration and Complications of Inflammation - Acute inflammation lasts a few days - Chronic inflammation can last months or years - Complications of inflammation include asthma, pneumonia, and autoimmune diseases

Causes of Inflammation - Infection - Physical injury - Autoimmune disorders

Classification of Inflammation - Acute inflammation is the initial response to harmful stimuli - Chronic inflammation involves a shift in cell types and simultaneous tissue destruction and healing - Inflammation can also be classified as Type 1 or Type 2 based on cytokines and helper T cells involved

Inflammation and Infection - Inflammation is the body's immunovascular response to harmful stimuli - Infection refers to microbial invasion and the body's inflammatory response - Inflammation can also be caused by non-infectious factors such as atherosclerosis and autoimmune diseases

Acute Inflammation - Acute inflammation is the first line of defense against injury. - Inflammatory mediators are short-lived and quickly degraded in the tissue. - Acute inflammation ceases once the stimulus is removed. - The inflammatory response involves the migration of leukocytes, mainly neutrophils and macrophages, to the site of injury. - Acellular biochemical cascade systems, such as the complement system and coagulation system, also contribute to the inflammatory response.

Chronic Inflammation - Chronic inflammation lasts for months or years. - Macrophages, lymphocytes, and plasma cells predominate in chronic inflammation. - Chronic inflammation is associated with diseases like diabetes, cardiovascular disease, allergies, and COPD. - Factors like obesity, smoking, stress, and insufficient diet can promote chronic inflammation. - A 2014 study reported that 60% of Americans had at least one chronic inflammatory condition.

Cardinal Signs of Chronic Inflammation - Common signs and symptoms of chronic inflammation include body pain, arthralgia, and myalgia. - Chronic inflammation can cause chronic fatigue, insomnia, depression, anxiety, and mood disorders. - Gastrointestinal complications like constipation, diarrhea, and acid reflux can occur. - Weight gain or loss may be observed in chronic inflammation. - Frequent infections can be a result of chronic inflammation.

Vascular Component of Acute Inflammation - Acute inflammation involves vasodilation and increased permeability of blood vessels. - Vasoactive amines like histamine and serotonin, as well as eicosanoids like prostaglandin E2 and leukotriene B4, contribute to vasodilation. - Nitric oxide released by macrophages and endothelial cells also contributes to vasodilation. - Increased permeability allows plasma fluid, containing important proteins, to move into the inflamed tissue. - The collection of fluid in the tissue causes swelling (edema) and facilitates antimicrobial actions.

Plasma Cascade Systems - The complement system promotes opsonization, chemotaxis, and agglutination. - The kinin system generates proteins that sustain vasodilation and other physical inflammatory effects. - The coagulation system forms a protective protein mesh over injury sites. - The fibrinolysis system counterbalances clotting and generates inflammatory mediators. - These plasma cascade systems play a crucial role in the inflammatory response.

Cellular Component - Leukocytes reside in the blood and move into inflamed tissue via extravasation. - Some leukocytes act as phagocytes, ingesting bacteria, viruses, and cellular debris. - Leukocytes release enzymatic granules that damage pathogenic invaders. - Leukocytes release inflammatory mediators that develop and maintain the inflammatory response. - Acute inflammation is mediated by granulocytes, while chronic inflammation is mediated by mononuclear cells.

Leukocyte Extravasation - Neutrophils migrate from blood vessels to infected tissue via chemotaxis. - Neutrophils remove pathogens through phagocytosis and degranulation. - Inflammation is a protective immune response against foreign organisms. - In autoimmune diseases, the immune system triggers an inflammatory response against normal tissues. - Leukocyte extravasation involves leukocyte margination, endothelial adhesion, transmigration, and movement within the tissue via chemotaxis.

Phagocytosis - Extravasated neutrophils come into contact with microbes at the inflamed tissue. - Phagocytes express endocytic pattern recognition receptors (PRRs) that bind to non-specific microbe-associated molecular patterns (PAMPs). - Actin-myosin cytoskeletal rearrangement occurs to endocytose the plasma membrane containing the PRR-PAMP complex and the microbe. - Phagosome is trafficked to intracellular lysosomes, forming a phagolysosome that kills microbes. - Opsonization enhances phagocytic efficacy by binding complement C3b and antibodies to microbial antigens.

Cell-Derived Mediators - Lysosome granules in granulocytes contain enzymes that act as inflammatory mediators. - GM-CSF, produced by macrophages, monocytes, T-cells, B-cells, and tissue-resident cells, contributes to inflammation in various conditions. - Histamine, stored in mast cells and basophils, causes arteriole dilation, increased permeability, and organ-specific effects. - IFN-γ, produced by T-cells and NK cells, has antiviral, immunoregulatory, and anti-tumor properties. - Cell-derived mediators play important roles in inflammation and its associated effects.

Other Factors - Inflammatory cytokines IL-1 and TNFα induce the expression of adhesion molecules on endothelial cells.