Gangrene: Types and Characteristics

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Questions and Answers

What is the primary cause of dry gangrene?

Arterial obstruction (correct)

Bacterial infection

Venous obstruction

Chemical exposure

What characteristic color and texture is associated with dry gangrene?

Wet and green

Yellow and moist

Red and swollen

Black and shrunken (correct)

Which type of gangrene typically leads to septicemia due to toxin absorption?

Dry gangrene

Wet gangrene (correct)

Fungal gangrene

Gas gangrene

Which bacteria are commonly associated with wet gangrene?

Clostridium perfringens Signup and view all the answers

What is the process called that leads to an abnormal increase in the size of an organ or tissue due to cellular size increase?

Hypertrophy Signup and view all the answers

Gas gangrene is primarily associated with which condition?

Deep contaminated wounds Signup and view all the answers

What nomenclature is most relevant when discussing cellular responses to injury and disease?

Cellular adaptations to stress Signup and view all the answers

Which adaptation is characterized by a decrease in tissue size due to a reduction in cell number or size?

Atrophy Signup and view all the answers

What type of atrophy is specifically characterized by muscle changes due to reduced activity?

Disuse atrophy Signup and view all the answers

What is the consequence of pressure atrophy on tissue?

Cuts off the blood supply to the tissue Signup and view all the answers

Which type of atrophy can result from the absence of trophic hormones?

Endocrine atrophy Signup and view all the answers

What distinguishes hypoplasia from atrophy?

Hypoplasia refers to incomplete growth of an organ. Signup and view all the answers

What type of metaplasia involves the transformation of columnar or cuboidal epithelium into stratified squamous epithelium?

Epithelial metaplasia Signup and view all the answers

Which term describes a complete failure of development of an organ during embryogenesis?

Agenesis Signup and view all the answers

What pathological condition arises from chronic irritation or avitaminosis A?

Epithelial metaplasia Signup and view all the answers

Vascular atrophy is primarily a result of which condition?

Chronic venous congestion Signup and view all the answers

Which type of hypertrophy is characterized by an increase in organ size due to the removal or destruction of one of two paired organs?

Compensatory hypertrophy Signup and view all the answers

What is the main distinction between physiological and pathological hyperplasia?

Physiological hyperplasia is a normal response, while pathological hyperplasia is an abnormal response. Signup and view all the answers

In which condition is left ventricular hypertrophy most likely to occur?

Aortic valvular stenosis Signup and view all the answers

Which of the following is a cause of pathological hyperplasia due to hormonal stimulation?

Hyperplasia of the mammary gland induced by estrogens Signup and view all the answers

What type of atrophy is characterized by the natural decrease in size of an organ as part of normal development?

Physiological atrophy Signup and view all the answers

Which statement accurately describes the difference between hyperplasia and hypertrophy?

Hyperplasia involves cell number increase, while hypertrophy involves cell size increase. Signup and view all the answers

Which type of pathological hyperplasia occurs in response to persistent irritation or injury?

Irritation-induced hyperplasia Signup and view all the answers

What is the primary feature of pathological hypertrophy compared to physiological hypertrophy?

Pathological hypertrophy is a response to disease or injury, while physiological hypertrophy results from normal physiological demands. Signup and view all the answers

Study Notes

Gangrene

Necrotic tissue with putrefaction, giving a black and foul-smelling appearance.
Caused by infection of necrotic tissue with putrefactive organisms.
Characterized by a dark coloration due to iron sulfide formation from the reaction of hemoglobin and hydrogen sulfide.

Types of Gangrene

Dry Gangrene:
- Affects only the skin surface.
- Primarily involves limbs, especially toes.
- Caused by arterial obstruction, common in individuals with impaired blood flow like diabetics.
- Tissue appears dry, shrunken, and dark reddish-black, resembling mummified flesh.
Wet Gangrene:
- Commonly affects organs like the small intestine, appendix, lung, and uterus, and can also occur in limbs.
- Caused by both arterial and venous obstruction, leading to tissue infection by saprophytic microorganisms like Clostridium perfringens or Bacillus fusiformis.
- Tissue appears wet, swollen, foul-smelling, and black or green.
- Systemic effects include septicemia and potentially death due to absorption of bacterial toxins.
Gas Gangrene:
- Affects deep contaminated wounds with significant muscle damage.
- Caused by gas-forming bacteria.
- Tissue becomes swollen with gas bubble formation.
- Infection spreads rapidly, resulting in severe toxemia.
- Less common in civilian settings, but a serious complication of war wounds.

Cellular Adaptations in Disease

Cells adapt to altered environments through physiological and pathological stimuli.
These adaptations involve changes in growth patterns, including hypertrophy, hyperplasia, atrophy, and metaplasia.

Importance of Cellular Adaptations

Common responses encountered in various diseases.
Some growth adaptations can create favorable conditions for later development of neoplasia (cancer).
These adaptations are frequently used in clinical practice.

Changes in Growth Pattern

1. Hypertrophy

Hyper = excess; trophy = nourishment
Abnormal increase in the size and weight of an organ or tissue due to enlarged cells.
Caused by increased functional demand of the tissue.
Types:
- Physiological Hypertrophy: E.g., Pregnant uterus, muscle growth due to exercise.
- Pathological Hypertrophy:
  - Compensatory: Occurs in paired organs if one is damaged or removed, leading to enlargement of the remaining organ. E.g., Kidney hypertrophy after removal of one kidney.
  - Adaptive: Occurs in muscular hollow organs to overcome chronic obstruction. E.g., Heart, stomach, bladder, or intestine hypertrophy in response to obstruction.
  - An example is Left ventricular hypertrophy in cases of aortic valvular stenosis.

2. Hyperplasia

Hyper = excess; plasia = formation
Increase in the size and weight of an organ or tissue due to increased number of cells.
Types:
- Physiological Hyperplasia: E.g., Growth of breast and genital organs at puberty.
- Pathological Hyperplasia: - Compensatory: E.g., Bone marrow hyperplasia after hemorrhage or excessive hemolysis. - Hormonal: E.g., Endometrial and mammary gland hyperplasia induced by estrogen injections. - Irritation: Can be caused by mechanical factors, bacterial infection, or toxicity. - Deficiencies: E.g., Iodine deficiency leading to thyroid hyperplasia. - Viral: E.g., Epithelial hyperplasia caused by poxvirus.

3. Atrophy

A = not (deprivation); trophy = nourishment
Decrease in the size of a tissue after full growth due to a decrease in cell number or size.
Types:
- Physiological Atrophy: E.g., Atrophy of the thymus.
- Pathological Atrophy:
  - General Atrophy:
    - Malnutrition and starvation atrophy: Due to lack of nutrients.
    - Senile atrophy: Age-related atrophy.
  - Localized Atrophy:
    - Disuse atrophy: Occurs due to inactivity.
    - Pressure atrophy: Resulting from sustained pressure on a tissue, often affecting blood supply.
    - Vascular atrophy: Due to insufficient oxygen and nutrients caused by anemia or chronic venous congestion.
    - Neurotrophic atrophy: Occurs when a trophic nerve is injured, leading to muscle atrophy.
    - Endocrine atrophy: Results from the absence of trophic hormones causing atrophy in the affected cells.

4. Metaplasia

Met = after; plasia = formation
Transformation of fully differentiated cells into another type of differentiated cells from the same germinal layer, adapting to environmental or functional changes.
Types:
- Epithelial Metaplasia (Squamous Metaplasia): Transformation of columnar or cuboidal epithelium into stratified squamous epithelium. Often occurs in the bronchi, bronchioles, gallbladder, and urinary bladder. Caused by chronic irritation and vitamin A deficiency.
- Connective Tissue Metaplasia (Osseous Metaplasia): Connective tissue converting into bone. Occurs during healing, for example in the abdominal wall.

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Description

This quiz explores the critical aspects of gangrene, focusing on its definition, types, and causes. Learn about the differences between dry and wet gangrene, their symptoms, and the underlying issues leading to these conditions. Perfect for nursing students or anyone interested in understanding this medical emergency.