Session 6: Inflammation

Question 1

What is Inflammation?

Answer 1

• Series of defensive biological reactions to harmful agents that lead to pain, redness, swelling, heat and loss of function in the affected areas of the body.
• The inflammatory response focuses host defense components at the site of an infection to eliminate microorganisms and heal damaged tissue.

Question 2

Inflammatory response and cells involved in acute inflammation

Answer 2

The acute inflammation process is achieved by the increased movement of plasma and
leukocytes from the blood into the injured tissues
– Blood vessels near the infected site become more permeable
– Polymorphonuclear leukocytes (PMNs) are the first cells to arrive at the site and release cytokines
– The liver produces C-reactive protein (CRP)

Question 3

List and define the 5 cardinal signs of inflammation

Answer 3

1. Heat (calor) - localized rise in temperature due to an increased amount of blood at the site
2. Redness (rubor) - result of increased blood in the area
3. Swelling (tumor) - accumulation of plasma and leukocytes at the site
4. Pain (dolor) - excess fluid in the tissues puts pressure on sensitive nerve endings, causing pain
5. Loss of function (functio lasea) - the result of swelling and pain (For example, inflammation of a finger would cause you to favor that finger and not use it in a normal manner).

Question 4

Chronic Inflammation

Answer 4

• It is a pathological condition that can destroy healthy tissue and cause more damage
  than the original problem. Pain is often absent.
• When inflammation becomes chronic, the inflammatory response can become so
  intense that it does permanent damage to the body tissues

Question 5

Why does Chronic Inflammation occur? Examples of some conditions

Answer 5

Chronic inflammation occurs because the body is unable to rid itself of invading organism. The invading microorganisms are persistent and stimulate an exaggerated immune response
Examples:
– Asthma
– Gingivitis
– Periodontitis

Question 6

The Chronic Inflammatory Process

Answer 6

• Characterized by an accumulation of macrophages which engulf and digest microorganisms.
• Leukocytes release inflammatory mediators that perpetuate the inflammatory response.
• Signs and symptoms of chronic inflammation may partially or completely disappear during a period of remission. May recur in a active period of disease known as exacerbation

Question 7

Chemical mediators associated with chronic inflammation

Answer 7

Chemical mediators are biologically active compounds secreted by cells that activate the body’s inflammatory response.
Important mediators include:
– Interleukins 1, 6 and 8 (IL-1, IL-6, and IL-8)
– Leukotrienes
– Prostaglandins (PGs)
– Tumor Necrosis Factor-alpha (TNF-α)

Question 8

Describe the differences between acute and chronic inflammation

Answer 8

• Acute inflammation is a short-term, normal process that protects and heals the body.
• Chronic inflammation is a long-lived, out-of-control inflammatory response that continues for more than a few weeks.
• Tissue damage is the hallmark of chronic inflammation.