Chapter Immunity and the Lymphatic System 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 selfantigens Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc Orderly Function of the Immune System Functional components of the immune system: lymphoid tissue • Primary – thymus, bone marrow • secondary – tonsils, adenoids, spleen, Peyer patches, appendix lymphocytes antibodies macrophages Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc Immunodeficiency Diseases (cont’d.) 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc Immunodeficiency Diseases (cont’d.) 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc Immunodeficiency Diseases (cont’d.) 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 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 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 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 12 Autoimmune Diseases (cont’d.) Systemic Lupus Erythematosus (SLE) 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 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 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 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 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 Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc 17 ... items © 20 09 by Saunders, an imprint of Elsevier Inc 15 Autoimmune Diseases (cont’d.) Myasthenia gravis (MG) Chronic progressive neuromuscular disorder Autoantibodies produced to acetylcholine... items © 20 09 by Saunders, an imprint of Elsevier Inc 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 Elsevier items and derived items © 20 09 by Saunders,