Acute inflammation Flashcards
What are the cardinal signs of acute inflammation?
The cardinal signs of acute inflammation are rubor (redness), calor (heat), tumor (swelling), and dolor (pain), Loss of function.
Describe the sequence of events in the vascular phase of acute inflammation.
The vascular phase involves increased blood flow to the area, increased permeability of blood vessels, and leakage of proteins and cells out of blood vessels.
List the mediators involved in the vascular phase of acute inflammation.
Histamine, bradykinin, leukotrienes, and prostaglandins are among the mediators released during the vascular phase of acute inflammation.
Explain the differences in the macroscopic appearance of acute skin inflammations caused by Staphylococcus aureus, Streptococcus pyogenes, and anthrax.
S. aureus typically produces a central zone of liquefactive necrosis with pus-filled cavity, while S. pyogenes results in cellulitis/impetigo with spreading redness. Anthrax presents with a black eschar.
What are the possible outcomes of acute inflammation?
Possible outcomes include resolution, suppuration, healing by fibrosis, progression to chronic inflammation, spread (direct or via blood vessels), or death.
Why is it important for neutrophils to continuously replace in the blood?
Neutrophils have a short lifespan and must be continuously replaced from the bone marrow to maintain effective immune response.
Define exudate, pus, pyogenic bacteria, abscess, bacteremia, septicemia, active hyperemia, passive hyperemia, transudate.
Exudate: Fluid rich in protein and cells.
Pus: A collection of dead neutrophils, bacteria, and tissue debris.
Pyogenic bacteria: Bacteria that induce pus formation.
Abscess: A localized collection of pus within a tissue.
Bacteremia: Presence of bacteria in the bloodstream.
Septicemia: Systemic infection associated with bacteremia.
Active hyperemia: Increased blood flow due to local vasodilation.
Passive hyperemia: Increased blood flow due to venous congestion.
Transudate: Fluid that passes through a membrane due to imbalance of hydrostatic and osmotic pressures.
Learning Objective 1:
List different types of cells which originate from a monocyte.
What are the cell types that originate from a monocyte?
Name the cells that are part of the mononuclear phagocyte system.
What are the functions of macrophages in the body?
The cells that originate from a monocyte include macrophages, which are part of the mononuclear phagocyte system. Macrophages function in phagocytosis of small and large particles, presentation of antigens to the lymphocyte system for antibody synthesis, secretion of factors stimulating fibrosis, and production of some components of complement.
earning Objective 2:
List the 7 phases of the cellular phase of inflammation and their mediators, and describe the functions of their mediators.
Can you name the phases of the cellular phase of inflammation?
Describe the events that occur during the margination of leukocytes.
What are chemotactic factors, and how do they influence inflammation?
Explain the process of phagocytosis during inflammation.
What is the significance of intracellular killing in the cellular phase of inflammation
he 7 phases of the cellular phase of inflammation are:
i. Slowing of blood flow
ii. Margination of leukocytes
iii. Triggering
iv. Strong adhesion
v. Motility
vi. Phagocytosis
vii. Intracellular killing
The mediators involved include selectins, integrins, bacterial products, leukotriene LTB4, and complement system by-products. These mediators facilitate leukocyte margination, adhesion, chemotaxis, phagocytosis, and intracellular killing of pathogens.
Learning Objective 3:
Describe in detail the pathogenesis of fever and rigors.
What causes fever during inflammation?
How do endogenous pyrogens contribute to fever?
Discuss the effects of fever on the body.
What are rigors, and how do they relate to fever?
Fever is caused by the action of pyrogens, which are released from polymorphs and macrophages stimulated by various factors such as antigen-antibody complexes, bacterial endotoxins, certain viruses, and pyrogenic lymphokines. Pyrogens act on the thermoregulator center in the hypothalamus, leading to an elevation of body temperature. Rigors are characterized by sudden, intense cold and shivering associated with fever and result from the body’s attempt to raise the internal temperature to match the new set point.
Learning Objective 4:
Define leucocytosis, lymphocytosis, and “right shift”.
Define leucocytosis and explain its significance.
What is lymphocytosis, and in what conditions does it occur?
Explain the concept of “right shift” in the context of leukocyte response.
Leucocytosis refers to an increase in the number of leukocytes in the bloodstream, which can be caused by various factors including infection, inflammation, or stress. Lymphocytosis specifically refers to an increase in lymphocytes in the blood, often seen in viral infections. “Right shift” refers to an increase in the proportion of immature neutrophils (bands) in the blood, which can indicate an ongoing inflammatory response.
Learning Objective 5:
List the systemic changes potentially seen in acute inflammation and discuss their pathogenesis.
What systemic changes can occur during acute inflammation?
Describe the role of pyrogens in inducing fever during inflammation.
How does acute inflammation lead to alterations in serum proteins?
Discuss the mechanisms underlying leucocytosis during acute inflammation.
Systemic changes in acute inflammation include fever, leucocytosis, and alterations in serum proteins such as increased gamma globulins and fibrinogen. Fever is caused by the action of pyrogens on the hypothalamus, while leucocytosis results from the release of mature and immature neutrophils from the bone marrow. Alterations in serum proteins occur as part of the acute phase response to inflammation.
Learning Objective 6:
List specific subtypes of acute inflammation, correlating their appearance with their pathological differences.
What are the subtypes of acute inflammation?
Describe the characteristics of suppuration and its consequences.
Explain the pathogenesis of cellulitis and its clinical manifestations.
Specific subtypes of acute inflammation include suppuration, characterized by pus formation and tissue necrosis, and cellulitis, which is a diffuse inflammation of connective tissue caused by bacteria. Suppuration often leads to abscess formation, while cellulitis spreads through the connective tissue due to factors produced by certain bacteria like haemolytic streptococci.
