When Our Immune System Breaks Down

1. When Our Immune System Breaks Down Immunopathology

2. Our bodies are constantly at war, under assault 24-hours a day from infection and toxins.

3. That we survive at all, is due to our immune system, -a network of chemicals & cells that protect the body.

4. Primary organs of immune system: • Thymus gland- processes T-lymphocytes which governs cellular immunity • Bone marrow- flexible tissue in bones that develops lymphocytes

5. Secondary organs of immune system: • Lymph nodes-filters fluids and pathogens • Spleen- creates lymphocytes for the destruction of old RBCs • Tonsils & Adenoids-lymph tissue

6. Main Job of the Immune System • Protects body from invasion of organisms • Protects body from own cells which may develop incorrectly and cause harm to the fine balance of the body's systems

7. Major cells of immune system: Leukocytes: • Polymorphonuclear leukocytes(granulocytes) - active in inflammatory process • Monocytes & Macrophages - engulf and eat pathogens 7 foreign substances • Lymphocytes - B & T lymphocytes; T-cell responsible for cell-mediated immunity processed by thymus (activated lymphocytes); B-cell responsible for antibody production

8. Crossing the barriers • First Line of Defense: • skin – provides innate immunity • mucosal membranes

9. B Cells • Develop in bone marrow • Provides Humoral Immunity (antibody production-plasma cells) • Enlarge and divide when antigens are encountered • Memory cells- remain dormant until reactivation by same antigens from past

10. T Cells • Produced by bone marrow • Matures in thymus • Identifies specific antigens • HELPER cells- activates and deactivates other immune cells; also suppressor cells that halt immune system • KILLER OR CYTOTOXIC cells- kill antigens

11. physical & chemical barrier can be broken down by: • trauma • as result of infection on surface invading microorganisms can enter body, blood stream & lymphatic system.

12. Inside the body, pathogens can find a niche in body tissue to multiply and form a colony.

13. Normally our bodies are fit enough to fight an infection with all the parts of our immune system.

14. Sometimes we need help fighting infection.

15. Antibiotics are chemicals developed to help us in the fight infection.

16. Antibiotics reduce risk of tissue damage while immune system fights off infection. • They also reduce risk of death if immune system is unsuccessful.

17. Antibiotics are not essential and we would often win without them.

18. The argument has been made that antibiotics are over prescribed.

19. For minor infections with low risks we should wait for the body's own defenses.

20. There is a protective effect of normal microorganisms which live on skin & mucosal membranes. These usually prevent other more dangerous bugs from spreading.

21. If for example you have a course of antibiotics for an infection… • as well as killing off the harmful bacteria causing the infection, • some of the good resident microbes will die, leaving an opportunity for others to grow.

22. Pathogens which grow under these conditions are called opportunistic pathogens.

23. A good example of an opportunistic infection: thrush or candida Note white fungal patches under tongue

24. This yeast-like fungus normally lives on skin, in gut & vagina in small, well-controlled numbers. After using antibiotics, fungi get a chance to multiply.

25. Hypersensitivity Disorders

26. Contact dermatitis http://www-medlib.med.utah.edu/WebPath/IMMHTML/IMM029.html

27. Hypersensitivity-contact dermatitis http://tray.dermatology.uiowa.edu/ImageBase.html

28. Photosensitive dermatitis http://tray.dermatology.uiowa.edu/ImageBase.html

29. Skin reaction to insect bite. Brown Recluse Spider

30. Poison Ivy Dermatitis http://health.discovery.com/diseasesandcond/encyclopedia/132.html

31. Hives

32. Allergic Welts http://www.dermatest.de/PB/Publikationen/PBEN/Allergic_skin_reactions/body_allergic_skin_reactions.html

33. Allergic Rhinitis http://www.emedicine.com/PED/topic2560.htm allergic rhinitis nose rub

34. “allergic shiners” as result of allergic rhinitis http://www.emedicine.com/PED/topic2560.htm

35. Nasal Polyp http://www.ghorayeb.com/NasalPolyps.html

36. http://www.ghorayeb.com/NasalPolyps.html

37. Hypersensitivity- Allergies • Some diseases results from a person’s immune response which causes tissue damage and disordered function rather than immunity • Hypersensitivity or allergies disease can be locally or systemically

38. Anaphalaxis • Hypersensitivity reaction in which antibody on mast cells quickly reacts with an antigen. • Mast cells release histamine & other mediators that lead to edema. • Local allergies- confined to skin and mucous membranes • Anaphaylactic shock- occurs throughout the body and can be life-threatening

39. Some causes of a hypersensitivity reaction:

41. acute laryngeal edema due to anaphylactic reaction to penicillin http://www-medlib.med.utah.edu/WebPath/IMMHTML/IMM030.html

42. Autoimmune Disorders

43. AutoImmunity • Immune response typically recognizes the difference between the person’s tissues and invaders; tolerance • When tolerance fails, the immune system attacks the body’s own system and individuals develop antibodies to their own tissues or self-antigens (autoantibodies)

44. patient with scleroderma note taunt skin and scaring at corners of mouth http://www-medlib.med.utah.edu/WebPath/IMMHTML/IMM024.html

45. Sclerodactyly as result of scleroderma http://www.dermis.net/doia/diagnose.asp?zugr=d&lang=e&diagnr=710110&topic=t

46. Lupus “butterfly rash” http://www-medlib.med.utah.edu/WebPath/IMMHTML/IMM009.html

47. Another lupus “butterfly rash” Also called “malar rash”

48. Myasthenia gravis Three different serial pictures demonstrate fatigue of eyelid muscles as patient keeps looking up. http://www.methodisthealth.com/health/nervsystem/Myasgrav.htm

49. Rheumatoid arthritis

50. X-ray rheumatoid arthritis http://www.vh.org/adult/provider/radiology/icmrad/skeletal/Parts/RAHands.html