Acute Inflammation: Body Defense Reaction

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Questions and Answers

What is the primary purpose of the body's inflammatory response?

To increase the body's temperature

To eliminate or limit the spread of injurious agents and remove necrosed cells and tissues (correct)

To cause harm to the body

To reduce the body's blood flow

What is the suffix that means inflammation?

osis

itis (correct)

algia

itis (correct)

What is the duration of acute inflammation?

Days to weeks

Months to years

Years to decades

Minutes, hours, few days (correct)

What is the fifth sign of acute inflammation?

Loss of function Signup and view all the answers

What is the role of mediators in acute inflammation?

To control the inflammatory response locally Signup and view all the answers

What is the first step of acute inflammation?

Recognition of injurious agent Signup and view all the answers

What is the result of increased permeability of blood vessels in acute inflammation?

Exudation of protein-rich fluid into tissues Signup and view all the answers

What is the difference between exudate and transudate?

Exudate is a fluid loss in inflammation, while transudate is a fluid loss due to hydrostatic pressure imbalance Signup and view all the answers

What is the result of arteriolar dilatation in acute inflammation?

Increased blood flow Signup and view all the answers

What is the result of vasodilatation of arterioles and capillaries in acute inflammation?

Increased blood flow and increased permeability Signup and view all the answers

What leads to increased lymphatic drainage?

Oedema Signup and view all the answers

What is a characteristic of pus?

A purulent exudate, rich in neutrophils and cell debris Signup and view all the answers

What is the process of neutrophils sticking to the endothelium?

Adhesion Signup and view all the answers

What is the function of exudation of fluid in acute inflammation?

Delivers plasma proteins to area of injury Signup and view all the answers

What is the result of vasodilatation in acute inflammation?

Increases temperature Signup and view all the answers

What is the purpose of pain and loss of function in acute inflammation?

To enforce rest, reduces chance of further traumatic damage Signup and view all the answers

Study Notes

Acute Inflammation

Definition: Local response of living tissues to injury due to any agent, aiming to eliminate or limit the spread of injurious agents and remove necrosed cells and tissues.

Inflammation Process

Involves 2 basic processes: inflammatory response and healing process
Complex host response for survival, involving host cells, blood vessels, proteins, and other mediators

Types of Inflammation

Acute inflammation: short duration (minutes, hours, few days), represents the early body reaction, usually followed by repair
Chronic inflammation: prolonged duration

Signs of Acute Inflammation

Redness (rubor)
Swelling (tumor)
Heat (calor)
Pain (dolor)
Loss of function

Acute Inflammation Changes

Vascular events: accumulation of fluid exudate and neutrophils in tissues, controlled by chemical mediators
Cellular changes: margination, rolling, emigration, transmigration, chemotaxis, activation, and phagocytosis

Causes of Acute Inflammation

Microbial infections
Hypersensitivity reactions
Physical agents
Chemicals
Tissue necrosis

Steps of Acute Inflammation

Recognition of injurious agent
Recruitment of leukocytes
Removal of agent
Regulation control of response
Resolution (repair process)

Vascular Changes

Vasodilation: increase in blood flow and permeability
Edema formation: increased permeability of blood vessels, leading to exudation of protein-rich fluid into tissues

Cellular Changes

Margination and rolling: neutrophils lining up and rolling along the endothelium
Emigration: neutrophils migrating through the blood vessel wall
Chemotaxis and phagocytosis: neutrophils migrating to the site of injury, phagocytosing microorganisms, and releasing toxic metabolites and enzymes

Exudate vs Transudate

Exudate: fluid loss in inflammation, high protein content, specific gravity above 1.02
Transudate: fluid loss due to hydrostatic pressure imbalance, low protein content, specific gravity less than 1.012

Oedema

Excess of fluid in interstitium, can be transudate or exudate
Leads to increased lymphatic drainage
Pus: a purulent exudate, rich in neutrophils and cell debris

Hallmark of Acute Inflammation

Exudate (of fluid): delivers plasma proteins, immunoglobulins, inflammatory mediators, and fibrinogen to the area of injury, dilutes toxins, and increases lymphatic drainage
Infiltrate (of cells): removes pathogenic organisms, necrotic debris, and delivers microorganisms to phagocytes and antigens to the immune system