Acute and Chronic Inflammation Flashcards
What are the 3 components of acute inflammation?
1) alterations in vascular caliber that lead to an increase in blood flow
2) structural changes in the microvasculature that permit plasma proteins and leukocytes to leave the circulation
3) emigration of leukocytes from the microcirculation, their accumulation in the focus of injury, and their activation to eliminate the offending agent
The increased blood flow and edema associated with acute inflammation lead to what 3 symptoms?
- redness (rubor)
- warmth (calor)
- swelling (tumor)
What causes pain during acute inflammation?
Leukocytes release prostaglandins, neuropeptides, and cytokines that cause tissue damage
Describe the order in which vascular flow changes
- vasodilation
- increased permeability of the microvasculature
- statsis
What mediators induce vasodilation?
histamine and nitric oxide most noteably
Why does stasis occur?
The loss of fluid results in concentration of red cells in small vessels which increases the viscosity of the blood
What is the hallmark of acute inflammation?
increased vascular permeability leading to the escape of a protein-rich fluid (exudate) into the extravascular tissue
What causes edema?
Exudate escapes into the extravascular tissue which increases the osmotic pressure of the interstitial fluid which leads to outflow of fluid into the interstitial fluid causing edema
Describe the 3 distinct phases of fluid loss from vessels during acute inflammation
1) immediate transient response lasting for 30 minutes or less, mediated mainly by the actions of histamine and leukotrienes on the endothelium
2) a delayed response starting at about 2 hours and lasting for about 8 hours, mediated by kinins, complement products, and other factors
3) a prolonged response that is most noticeable after direct endothelial injury
What is Transmigration aka?
diapedesis
What is suppurative or purulent inflammation characterized by?
the production of large amounts of pus or purulent exudate consisting of neutrophils, necrotic cells, and edema fluid
What is serous inflammation marked by?
the outpouring of a thin fluid that, depending on the size of injury, is derived from either the plasma or the secretions of mesothelial cells lining the peritoneal, pleural, and pericardial cavities (called effusion)
What can be defined as a local defect, or excavation, of the surface of an organ or tissue that is produced by the sloughing (shedding) of inflammatory necrotic tissue?
an ulcer
What can be defined as inflammation of prolonged duration (weeks or months) in which active inflammation, tissue destruction, and attempts at repair are proceeding simultaneously?
chronic inflammation
How does chronic inflammation typically begin?
insidiously, as a low-grade, smoldering, often asymptomatic response
