Inflammation Study Guide

Erythema (redness) results from vasodilation and increased blood flow.
Heat is also caused by vasodilation and increased blood flow.
Edema occurs due to increased vascular permeability and hydrostatic pressure, leading to fluid filtration into interstitial spaces.
Pain can originate from direct trauma, pressure from edema, swelling of nerve endings, and chemical mediators.

Acute inflammation mainly involves edema (fluid and plasma proteins) and neutrophilic migration.
Chronic inflammation includes infiltration of lymphocytes, plasma cells, and macrophages, promoting endothelial cell and fibroblast growth leading to granulation tissue.
Chronic inflammation features angiogenesis (new blood vessel formation), fibrosis (scarring), and tissue destruction.

Common causes of acute inflammation include infections, tissue necrosis, foreign bodies, and immune reactions.
Chronic inflammation may arise from extensive necrosis, areas with impossible tissue regeneration (e.g., heart, CNS, PNS), persistent injurious agents, or repeated episodes of acute inflammation.

Exudate is a high protein fluid with abundant cellular content due to increased vascular permeability.
Transudate is low in protein and cells, resulting from normal Starling’s forces without increased permeability.
Effusion refers to fluid leakage into an anatomic or potential space, which can either be exudate or transudate.

Inflammation goals include enhancing the movement of plasma proteins and cells to the injury site, termed “exudation.”
Increased capillary permeability leads to fluid and protein leakage; vasodilation initially increases blood flow.
Following fluid leakage, blood flow decreases, increasing blood viscosity and potentially leading to clotting from raised fibrinogen levels.
Leukocyte migration and accumulation are essential for pathogen elimination.

Leukocytes work to remove harmful stimuli, release substances to degrade pathogens, perform phagocytosis, and release growth factors for healing.
Stasis occurs when blood flow slows and vessels engorge.
Margination describes leukocytes accumulating along endothelial cells due to adhesion molecule interaction.
Diapedesis is the process where leukocytes migrate from blood vessels into the interstitial space by squeezing through endothelial cells.
Chemotaxis involves chemokines attracting leukocytes to the injury site.

Lymphatic vessels drain exudate from tissues, reducing edema and removing inflammatory stimuli and leukocytes.
Phagocytes present antigens in lymph nodes, leading to proliferation of B and T cells, which can cause lymphadenopathy (enlargement of lymph nodes).

Inflammation of lymphatic vessels, often presenting as red streaks on the skin and painful upon palpation.

Histamine is stored in granules within mast cells, basophils, and platelets, promoting endothelial contraction, increased vascular permeability, exudation, vasodilation, and bronchoconstriction.