Body Systems and Disorders The Immune System Body Systems and Disorders

Lymphatic System Supplements the circulatory system Composed of lymph, lymph nodes, lymph vessels, the spleen, the thymus gland, lymphoid tissue in the intestinal tract, and the tonsils There is no muscular pump or heart

Functions Acts as intermediary between blood and tissue Transports excess tissue fluid Produce lymphocytes and filters out harmful bacteria

Lymph Straw colored Called intercellular, interstitial fluid or tissue fluid Composition of lymph Moves with assistance of skeletal tissue contraction, breathing movements, and valves

Lymph Vessels Closely parallel the veins Right lymphatic duct Left lymphatic duct (thoracic duct) Flows in only one direction

Lymph Nodes Small structures located alone or grouped in various places along the lymph vessels throughout the body When germinal centers are stimulated, the immune response is activated

Tonsils Masses of lymphatic tissue Produce lymphocytes Filter out bacteria

Tonsils Tonsillitis – Infected tonsils. Symptoms: Difficulty swallowing; sore throat; elevated temp; chills. Treatment – antibiotics if bacterial or in extreme cases surgery. FYI – Tonsils get smaller in size as a person gets older.

Spleen Saclike mass of lymphatic tissue Located upper left of the abdomen beneath the diaphragm Forms lymphocytes and monocytes Filters out bacteria Stores red blood cells

Thymus Gland Located in the upper anterior part of the thorax, above the heart Produces T-lymphocytes It is also an endocrine gland which secretes a hormone called thymosin

Disorders of the Lymph System Lymphadenitis – enlargement of the lymph nodes Hodgkin’s disease – cancer of lymph nodes. Early symptom: painless swelling of the lymph nodes. Treatment: chemotherapy and radiation.

Disorders of the Lymph System Infectious mononucleosis – caused by Epstein-Barr virus. Frequently occurs in young adults & children. Spread by oral contact – also known as “kissing disease.” Symptoms: enlarged lymph nodes; fever; physical/mental fatigue. In- crease in number of leukocytes. Treatment: symptomatically; bed rest. In some cases liver may be affected and hepatitis can result.

Immunity When pathogens and foreign materials penetrate the skin the person’s immunity comes into play Immunity is the body’s ability to resist these invaders Individuals differ in their ability to resist infection

Immunity Resistance varies at different times Natural immunity Immunity we are born with Acquired immunity Reaction that occurs as a result of exposure to invaders Passive acquired immunity Acquired artificially by injecting antibodies

AIDS/HIV A – Acquired I – Immune D – Deficiency The disease is not inherited I – Immune Refers to body’s natural defenses against cancers, disease, and infections D – Deficiency Lacks cellular immunity

AIDS/HIV S – Syndrome Human immunodeficiency virus (HIV) causes AIDS Involves the set of diseases or conditions that are present to signal the diagnosis Human immunodeficiency virus (HIV) causes AIDS HIV destroys the body’s T4-lymphocyte cells Opportunistic infections

Transmission of AIDS Sexual contact Sharing hypodermic needles In utero or at birth

Screening Tests for HIV/AIDS ELISA – enzyme-linked immunosorbent assay is an AIDS antibody indicator. Detects the antibodies for AIDS but not the virus itself. Western blot – follow up to confirm the ELISA results. Rapid test – test of blood or oral fluid to check for the presence of antibodies to HIV. Produces results in approx. 20 min.

Symptoms of HIV/AIDS Flu-like symptoms – beginning stages More persistent symptoms include – coughing; shortness of breath; seizures; mental symptoms; fever; weight loss; abd cramps; persistent diarrhea. Symptoms may not occur for 10 years after initial infection. Opportunistic conditions – include cancers; parasitic infections; fungal infections; viral infections; higher risk for T.B. and syphilis.

Treatment of HIV/AIDS No cure for AIDS Prevention and treatment have prolonged and improved the lives of many

Preventing Transmission of HIV/AIDS Limit sexual contacts Have protected sex Do not share needles Clean up soiled materials Cover wounds Standard precautions used by all health care workers

Medical Terminology