Inflammation: Causes and Terminology

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Questions and Answers

What term is commonly used to refer to inflammation of a specific organ?

pathy

itis (correct)

itis-itis

osis

Which of the following is NOT a recognized cause of inflammation?

Physical irritants

Allergens (correct)

Infectious agents

Chemical irritants

What does the Latin root 'inflammare' translate to in English?

To heal

To set something on fire (correct)

To cause pain

To protect

Which of the following options describes a primary function of inflammation?

Repair tissue damage Signup and view all the answers

Which of the following conditions would likely NOT lead to inflammation?

Nutrition overload Signup and view all the answers

What is the primary role of inflammatory cells in the inflammation process?

To facilitate healing and defense Signup and view all the answers

Which type of inflammation is characterized by a prolonged duration and often leads to tissue damage?

Chronic inflammation Signup and view all the answers

Which of the following conditions could be classified as a nutritive irritant leading to inflammation?

Vitamin deficiencies Signup and view all the answers

What characterizes focal inflammation?

Single inflamed area within a tissue Signup and view all the answers

Which of the following can result from acute inflammation?

Hyperemia Signup and view all the answers

What does diffuse inflammation involve?

All tissue or organs affected by inflammation Signup and view all the answers

Which of the following is NOT considered a cardinal sign of inflammation?

Increase in heart rate Signup and view all the answers

How does acute inflammation typically progress?

Resolves quickly or evolves into chronic inflammation Signup and view all the answers

What type of lesions are present in peracute inflammation?

Hyperemia, slight edema, hemorrhage, and few inflammatory cells Signup and view all the answers

What causes the sensation of pain (Dolor) in an inflamed area?

Chemicals irritating sensory nerve endings and pressure from swelling Signup and view all the answers

What defines the term 'duration' in the context of inflammation?

How long the inflammation persists Signup and view all the answers

What characteristic appearance does pus produced by Corynebacterium exhibit?

Greenish Signup and view all the answers

What color does pus turn when produced by Pseudomonas aeruginosa?

Bluish-green Signup and view all the answers

What is a key characteristic of hemorrhagic inflammation?

High erythrocyte content in exudate Signup and view all the answers

In fibrinous inflammation, what is primarily exuded due to endothelial cell injury?

Fibrinogen Signup and view all the answers

What does a thick, stringy, elastic exudate indicate in fibrinous inflammation?

Severe endothelial cell injury Signup and view all the answers

How does blood from the posterior portion of the intestine appear in feces?

Bright red Signup and view all the answers

What is observed microscopically in purulent inflammation?

Numerous living and dead neutrophils Signup and view all the answers

What is a primary cause of the loss of function in an inflamed area?

Pain Signup and view all the answers

What distinguishes a diphtheritic membrane from a croupous membrane?

It leaves ulcerated mucosa Signup and view all the answers

Which microscopic lesion is characterized by the migration of blood leukocytes into extravascular tissue?

Leukocytic infiltration Signup and view all the answers

What type of acute inflammation is characterized by the presence of clear to slightly yellow watery fluid?

Serous inflammation Signup and view all the answers

Which type of acute inflammation occurs primarily in mucous membranes of the respiratory, digestive, and urogenital tracts?

Catarrhal inflammation Signup and view all the answers

In which type of inflammation are the surfaces covered with or containing pus?

Purulent (suppurative) inflammation Signup and view all the answers

What type of acute inflammation is often induced by pyogenic bacteria?

Purulent inflammation Signup and view all the answers

Which exudate type is associated with hyperemia, leukocytic infiltration, and the presence of mucin?

Catarrhal exudate Signup and view all the answers

What is a characteristic feature of exudate in acute inflammation?

Its character depends on causative agents. Signup and view all the answers

What is a key characteristic of hemorrhagic inflammation compared to normal inflammation?

Absence of cardinal signs Signup and view all the answers

Which cell type is primarily involved in acute inflammatory responses?

Neutrophils Signup and view all the answers

Which of the following is NOT a microscopic characteristic of chronic inflammation?

Absence of lymphocytes Signup and view all the answers

What is a common cause of chronic inflammation?

Unique virulence factors of pathogens Signup and view all the answers

What causes the firm consistency seen in chronic inflammatory lesions?

Deposition of fibrous connective tissue Signup and view all the answers

Which of the following describes the gross appearance of chronic inflammation?

Gray to white due to cellular infiltrates Signup and view all the answers

Which type of leukocyte is primarily involved in allergic diseases?

Eosinophils Signup and view all the answers

What is the main role of basophils in the inflammatory process?

Mediating allergic reactions Signup and view all the answers

Study Notes

Definition of Inflammation

Inflammation is a vascularized living tissue's reaction to injury
The term "inflammation" stems from the Latin word "inflammare," meaning "setting something on fire"

Nomenclature of Inflammation

Inflammation of a specific organ or tissue is usually indicated by the suffix "-itis" attached to the organ's Latin name
Examples include "dermatitis" for inflammation of the skin and "hepatitis" for inflammation of the liver
The suffix "-itis" generally signifies "diseases characterized by inflammation"
Some inflammation terms don't end in "-itis," such as "pleurisy" (inflammation of the pleura) and "pneumonia" (inflammation of the lung)

Causes of Inflammation

Causes are numerous and diverse, including:
- Infectious agents: bacteria, viruses, fungi, and parasites
- Physical irritants: excessive heat, cold, ionizing radiation, heatstroke
- Chemical irritants: caustic agents, poisons, venom
- Nutritive irritants: ischemia, vitamin deficiencies
- Endogenous causes: hypersensitivity and autoimmune reactions

Functions of Inflammation

Inflammation is often a protective mechanism with the following primary purposes:
- Dilute, isolate, and eliminate the causative agent
- Repair tissue damage caused by the injury

Classification of Inflammation

Inflammation can be categorized according to:
- Distribution (Location within an organ)
  - Focal: A single inflamed area within a tissue, ranging in size from 1 mm to several centimeters
  - Multifocal: Several foci separated by relatively normal tissue, with variable size
  - Locally Extensive (Focally Extensive): Significant involvement of an area within an organ
  - Diffuse Inflammation: Involves all tissue or an entire organ
- Severity (How severe is the process?): Mild, Moderate, or Severe
- Duration (How long does it persist?):
  - Peracute Inflammation: Characterized by a very short course, caused by potent stimuli like African swine fever, clostridial infection, avian influenza, African horse sickness, and anthrax. Lesions include hyperemia, slight edema, hemorrhage, and few inflammatory cells.
  - Acute Inflammation: A short-term process (hours to days) appearing rapidly after exposure to the causative agent. Progresses to either resolution or chronic inflammation.
    - Gross Lesions: Cardinal signs of inflammation
      - Redness (Rubor)
      - Hotness (Calor)
      - Swelling (Tumor)
      - Pain (Dolor)
      - Loss of function (Functiolaesa)
    - Microscopic Lesions:
      - Vascular Congestion: Distension of blood vessels with blood
      - Leukocytic Infiltration: Migration of blood leukocytes to the extravascular tissue (leukocyte margination, rolling, adhesion, and transendothelial cell migration)
      - Presence of Exudate (Inflammatory Fluid)
        
        Types of Acute Inflammation based on Exudate Character:
        
        Serous Inflammation: Clear to slightly yellow, watery fluid within the tissue, possibly forming raised fluid-filled vesicles
        
        Catarrhal Inflammation: Inflammation of mucous membranes in digestive, respiratory, and urogenital tracts. Grossly, it appears covered or contains mucous. Microscopically, hyperemia, leukocytic infiltration, and mucin are present.
        
        Purulent (Suppurative) Inflammation: Caused primarily by pyogenic bacteria. Characterized by the production of pus, which can vary in consistency and color depending on the causative agent and species.
        
        Hemorrhagic Inflammation: Due to severe irritants causing vascular injury and an exudate rich in erythrocytes
        
        Fibrinous Inflammation: Exudation of fibrin-rich fluid due to severe irritants that damage endothelial cells and allow leakage of large proteins like fibrinogen, which polymerizes into fibrin in the extracellular space.

Chronic Inflammation

Chronic Inflammation: Inflammation of prolonged duration (weeks, months, or years) marked by chronic inflammatory cell infiltration and fibroplasia.
Causes:
- Failure of the acute inflammatory response to eliminate the causative agent
- Repeated episodes of acute inflammation
- Unique properties of the causative agent
Gross Picture:
- Grey to white color due to macrophage and lymphocyte infiltrates, fibroblast proliferation, and fibrous connective tissue deposition
- Firm consistency due to fibroblast proliferation, fibrous connective tissue deposition, and exudate solidification
- Irregular shape due to:
  - Haphazard accumulation of leukocytes
  - Fibrosis
  - Contraction of the lesion by myofibroblasts within the fibrous connective tissue
Microscopic Picture:
- Chronic Inflammatory Cell Infiltrate: Lymphocytes, macrophages, plasma cells, epithelioid cells, and sometimes multinucleate giant cells
- Fibroplasia: Proliferation of fibroblasts and collagen deposition

Inflammatory Cells

Acute Inflammatory Cells
- Neutrophils: The first leukocytes recruited to the inflammatory exudate, prominent in suppurative inflammations
- Mast Cells: Initiate acute inflammatory responses
- Eosinophils: Crucial role in allergic and parasitic diseases
- Basophils: Important role in allergic diseases
Chronic Inflammatory Cells
- Macrophages:
- Epithelioid Cells: Larger than activated macrophages with abundant cytoplasm but diminished phagocytic capacity. Their physiological activity remains unclear.

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Description

This quiz explores the definition, nomenclature, and causes of inflammation. Learn about the various forms of inflammation and their linguistic roots. Test your knowledge of terms like '-itis' and the factors leading to inflammation.