Inflammation 3: Acute suppurative Inflammation Flashcards
Define acute suppurative inflammation
acute inflammation formed by virulent bacteria, forming pus as a result
define pus
Liquefied material mixed with Pus cells, exudate, neutrophils & necrotic fluid
describe pathogenesis of pus
- Virulent bacteria causes necrosis of tissue
- as a result, it attracts neutrophils
- it then kills neutrophils by leukocidins, causing leukocytes (neutrophils) to die and release their proteolytic enzymes
- proteolytic enzymes cause digestion & liquefaction of necrotic tissue
Pus cells are ____
dead neutrophils
virulent bacteria kills neutrophils by ____
leukocidins
description of pus
- tubrid creamy
- Doesn’t coagulate on standing
- yellow when caused by staphelococus aureus
- sanguineous when caused by streptococus
- green when caused by pyocyaneous
types of Acute suppurative inflammation
- Localized suppurative
- Diffuse suppurative
explain why pus doesn’t coagulate on standing
due to release of proteolytic/lysosomal enzymes
bacteria causing Localized Suppurative acute inflammation
Staphylococcus Aureus
bacteria causing Diffuse Suppurative acute inflammation
Streptococcus hemolyticus
Enzyme specific to staphylococcus Aureus, and its function
Coagulase enzyme;
localization of bacteria by formation of Fibrin
Enzyme specific to Streptococcus hemolyeticus & function
- Spreading factor= Hyaluronidase enzyme
- Virulence factors= streptokinase & Fibrolysin
their function is spreading of the bacteria
Enumerate types of Localized Suppurative Acute inflammations
- Furuncle (boil): hair follicle (folliculitis)
- Carbuncle: multiple communicating SC absesses with multiple sinuses at the surface
- Abscess
most common site for carbuncle
in the back of the neck
Carbuncle is more in pateints with ____
Diabetes
Enumerate & describe complications arriving with abscess
-
Spread:
direct
Blood (septicemia, toxemia, pyemia)
Lymphatics (lymphangitis, Lymphadenitis) - Ulcer: local defect with surface
- Sinus: blind ended tract connecting deep abscess to surface
- Fistula: Double ended tract connecting 2 surfaces or hollow organs
- Keloid
- Rupture
- Hemorrhage
- Chronicity of the abscess
- Putrefaction
- Compression
Cause of Abscess
Pyogenic bacteria= Staphylococcus aureus bacteria
as it is a Localized suppurative acute inflammation
enumerate routes of abscess formation
- bacteria is seeded into tissue (such as in surgery)
- Secondary infection of necrotic tissue
Describe the morphology of abscess
3 zones:
* Central: Necrosis (which gradully decreases peripherally)
* Mid Zone: Liquifaciton zone (pus)
* Peripheral zone: pyogenic membrane
Pyogenic membrane/ Abscess is area is rimmed by:
- Neutrophils (preserved)
- macrophages
- Dilated capillaries
- fibrin
- Fibroblasts
fate of abscess
- Small: absorbed then healed
- Large: if not surgically removed, it ruptures (evacuation) and then heals by scar tissue
describe pus of diffuse suppurative acute inflammation
thin & sanguineous (colour of blood) (due to hemolysis of RBCs)
Enumerate types of diffuse suppurative acute inflammation
- Cellulitis
- acute diffuse suppurative appendicitis
- septic peritonitis
cellulitis is more common in patients with ____
Diabetes
common site of cellulitis
- Loose tissue= subcutaneous
- Loose areolar tissue= Scrotum or Orbit
