1. Chapter 2 Immunity and the Lymphatic System

2. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 1 Immunity  Immunity: The ability of the body to defend itself against infectious agents, foreign cells and even abnormal body cells.  Specific immunity: Also known as acquired immunity, effective against particular identified foreign agents and develops in response to contact with that agent.  Autoimmunity: Occurs when individuals develop antibodies to their own tissues or self-antigens.

3. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 2 Orderly Function of the Immune System  Functional components of the immune system:  lymphoid tissue Primary – thymus, bone marrow Primary – thymus, bone marrow secondary – tonsils, adenoids, spleen, Peyer patches, appendix secondary – tonsils, adenoids, spleen, Peyer patches, appendix  lymphocytes  antibodies  macrophages

4. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 3 Orderly Function of the Immune System (cont’d.)  Major functions of the immune system:  Protect the body against foreign organisms  Maintain homeostasis by eliminating damaged cells (phagocytosis)  Battles infection

5. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 4 Orderly Function of the Immune System (cont’d.)  Inappropriate responses of the immune system:  Hyperactive (allergic) – excessive response  Immunodeficient (e.g., AIDS) – inadequate response  Autoimmune (e.g., SLE) – misdirected response  Transplant rejection – attack to beneficial foreign tissues

6. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 5  Acquired Immunodeficiency Syndrome (AIDS)  Caused by human immunodeficiency virus (HIV)  Diagnosed by presence of HIV antibodies in the blood (common test: ELISA; confirmation: Western blot)  HIV attacks helper T lymphocytes  Reduces cell-mediated immunity  Attacks nervous system directly Immunodeficiency Diseases (cont’d.)

7. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 6  HIV transmission is through direct contact with blood or semen of infected person  sexual contact  blood transfusions and other blood products  contaminated shared needles (IV drug use, etc.)  accidental needle sticks  to fetus via placenta or during birth process from infected mother Immunodeficiency Diseases (cont’d.)

8. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 7 Universal Precautions  Thorough and frequent hand washing.  Personal protective equipment worn as required by specific task (e.g. gloves, gown, goggles, mask).  Proper disposal of all sharps in designated biohazard containers.  No needle recap prior to disposal.  Caution in handling of laboratory specimens.  Proper containment and disinfection of blood and body fluid spills.  Use clean mouthpieces and resuscitation bags. Immunodeficiency Diseases (cont’d.)

9. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 8 Autoimmune Diseases  Lymphocytes and antibodies are sensitized to develop against the body’s own organs or tissues.  May be triggered by disease, injury, metabolic changes, or mutation in immunologically competent cells.  May be caused by certain drugs or chemicals, trauma, or viral infection.

10. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 9 Autoimmune Diseases (cont’d.) Pernicious Anemia  Symptoms: weakness and tingling and numbness in extremities, altered vision, lightheadedness, tinnitus, palpitations, weight loss, digestive disturbances, sore tongue.  Signs: decreased red blood cell, white blood cell, and platelet counts; increased red blood cell mean volume; decreased hemoglobin levels; jaundice; optic nerve atrophy; decreased amount of gastric acid.

11. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 10 Autoimmune Diseases (cont’d.) Connective Tissue Diseases  Systemic lupus erythematosus  Scleroderma  Sjogren syndrome  Rheumatoid arthritis  Juvenile rheumatoid arthritis  Ankylosing spondylitis  Polymyositis

12. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 11 Autoimmune Diseases (cont’d.) Systemic Lupus Erythematosus (SLE)  Inflammation of skin, joints, nervous system, kidneys, lungs, and other organs.  Butterfly rash across face may be present.  Other rashes may appear on other exposed skin areas.

13. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 12 Autoimmune Diseases (cont’d.)  Butterfly face rash  Alopecia  Photosensitivity  Raynaud’s phenomenon  Thrombocytopenia  Discoid skin lesion  Nasopharyngeal ulceration  Polyarthritis  Pleuritis or pericarditis  Protein or casts in the urine  Hemolytic anemia  False-positive serology  Abnormal blood antibodies  LE cells (leukocytes) present in lab testing Systemic Lupus Erythematosus (SLE)

14. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 13 Autoimmune Diseases (cont’d.)  Rheumatoid arthritis (RA)  Chronic, inflammation and edema of the synovial membranes surrounding joints.  Destruction of cartilage and adjacent bone.  May produce weight loss, fever, and malaise.  Joint pain and stiffness, especially in morning.  Bilateral joint tenderness, edema, erythema, warmth.

15. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 14 Autoimmune Diseases (cont’d.)  Multiple sclerosis (MS)  Inflammatory disease of the central nervous system.  Demyelination of nerves occurs in the brain and spinal cord.  Signs and symptoms are primarily neurologic and related to areas of myelin destruction.

16. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 15 Autoimmune Diseases (cont’d.) Myasthenia gravis (MG)  Chronic progressive neuromuscular disorder.  Autoantibodies produced to acetylcholine receptor in muscle cells.  Ineffective nerve-muscle junction results in severe weakness, difficulty talking and swallowing, drooping eyelids and diplopia.

17. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. 16 Autoimmune Diseases (cont’d.)  Vasculitis  Inflammation in the walls of blood vessels that may lead to necrosis, thrombus formation, and local infarct  Can be classified as small vessel or systemic; affecting medium and large arteries