A classification of disease

• The body is made in a certain way and functions uniquely. This is called Anatomy and Physiology
• Changes to the normal anatomy or physiology of the human body is called pathophysiology.
• Three very important pathological changes are:

  1. Death of part or all of the body
  2. Inflammatory reaction (or inflammation)
  3. Neoplasm (or Cancer formation)
• Inflammation

  A response of a tissue to injury, often injury caused by invading parasites.
• Characteristics of inflammation

  1. Increased blood flow to the tissue
  2. Increased blood flow causes temperature rise
  3. Swelling
  4. Pain
• Inflammation

  The change happens in a tissue when injured if the injury does not destroy the tissue.
• Some causes of inflammation

  1. Trauma
  2. Infection
  3. Chemicals
  4. Allergy
• Two main types of inflammation

  1. Acute
  2. Chronic
• The type and amount of inflammation depends on the cause
• Acute injury or infection

  Conditions that need immediate attention.
• Chronic mild injury or infection

  Results in long-lasting inflammation
• Acute inflammation


  A rapid response to an injurious agent that serves to deliver mediators of host defense leukocytes and plasma protein to the site of injury.
• 3 major components of acute inflammation

  1. Alterations in vascular caliber that lead to an increased blood flow.
  2. Structural changes in the microvasculature are the smallest vessels, such as the capillaries, arterioles, and venules that permit plasma and leukocytes to leave the circulation
  3. Emigration of the leukocytes from the microcirculation, their accumulation in the focus of injury, and their activation to eliminate the offending agent (Robbins,7th ed)
• Cytokines

  Proteins that serve as messengers between cells
• Efflux

  Means flow out
• The different components of the inflammatory responses are mediated by different signals and serve distinct (and overlapping) functions.
• The vascular phenomena of acute inflammation are characterized by increased blood flow to the injured area, resulting mainly from arteriolar dilation and opening of capillary beds induced by mediators such as histamine.
• If the injurious agent cannot be quickly eliminated, the result may be chronic inflammation.
• Increased vascular permeability results in the accumulation of protein-rich extravascular fluid, which forms the exudate.
• Exudate

  A fluid with a high content of protein and cellular debris which has escaped from blood vessels and has been deposited in tissues or on tissues.
• Rubor


  Redness
• Warmth

  Calor
• Swelling

  Tumor
• Redness, warmth, and swelling of acute inflammation are caused by increased blood flow and edema.
• Dolor

  Pain
• Signs and symptoms of chronic inflammation:

  1. Swelling but not usually very much
  2. Redness is not usual
  3. Slight heat
  4. Not much pain and tenderness
  5. Loss of function is common
  6. Potential fluid or pus presence
• To eliminate chronic inflammation, remove the cause.
• The affected body part may be unable to function properly if that site is:

  1. Badly damaged
  2. Very scarred
• Shivering 


  Rigors
• Neoplasm


  Also called new growth, tumor, or cancer.
• Neoplasm

  The growth of abnormal body cells which keep on growing where and when they are not needed.
• Known causes of neoplasm:

  1. Chemicals
  2. Some drugs
  3. Certain viruses
  4. Excessive sunlight
  5. Radiation from atomic bombs
• Two types of neoplasm:

  1. Benign (simple) neoplasm
  2. Malignant (complex) neoplasm
• Two types of malignant neoplasms:

  1. Primary-Neoplasm at the place it started
  2. Secondary-Neoplasm at the place it has spread to from the primary neoplasm
• Different ways neoplasms damage the body

  1. Destruction
  2. Obstruction
  3. Pressure
  4. Ulceration
  5. Wasting & malaise