Disorders of the Blood and Immune System
BCE 542 (Physical Disabilities, Rehabilitation and Employment) Dr. Dunn November 26, 2002
Disorders of the Blood and Immune System
• Blood Dyscrasias – Anemia – Polycythemia – Agranulocystosis • Sickle Cell Diseases – Sickle Cell Anemia – Hemoglobinopathy SC – Sickle Thalassemia – Sickle Cell Trait • Hemophilia • AIDS/HIV Spectrum
Blood Dyscrasias
• Reduced red blood cell count or weakened hemoglobin in bloodstream. • Types: – Aplastic Anemia: Malfunction of the bone marrow; new red blood cells are not produced. – Hemolytic Anemia: Red blood cells destroyed faster than the body can produce them. – Iron Deficiency Anemia: The body is unable to metabolize iron, or iron intake is insufficient. – Pernicious Anemia: Inadequate intake or poor metabolization of vitamin B12 • Symptoms: Exhaustion; increased heart rate, pallor, shortness of breath • Treatment: – Aims at correcting cause of problem; dietary changes are often necessary. – Blood transfusions may be necessary until individual can maintain an adequate red blood count.
Anemia
Polycythemia
• Overabundance of red blood cells, causing thickening of the blood. • Difficulties in circulation can result in cardiovascular problems (stroke, heart attack, hypertension, congestive heart failure) • Symptoms and causes are similar to those for anemia. • Treatment aims at correcting cause of the problem, thinning the blood (coumadin, increased fluid intake).
Agranulocystosis
• Reduction of neutrophils, a type of white blood cell, dramatically reducing the ability to fight infection. • Usually caused by exposure to a variety of poisons. • Medical emergency. • Treatment: Massive doses of antibiotics and removal of toxins/detoxification.
Rehabilitation: Blood Dyscrasias
• Usually not a serious concern if brought under control and managed. • When disorder is active, individuals will have serious problems with mental and physical vitality; person should not be placed in overly-strenuous activities. • Unmanageable blood dyscrasias usually result from other, more serious disorders which will place additional restrictions on the individual.
Sickle Cell Diseases
What is a sickle cell?
• Normal red blood cells look like “donuts;” have a life span of about 120 days. • In sickle cells, blood cells have defective hemoglobin that wears down after 10-14 days; as cells wear out they acquire a “sickle” shape. • Sickle cells are destroyed more often in liver, causing the liver to overproduce bile and place more of certain amino acids into the bloodstream, causing jaundice. • Sickle cells also cannot carry oxygen as efficiently as normal cells. • A variety of other complications can develop (discussed shortly)
Sickle Cell Disease: Causes
• Abnormal hemoglobin is genetic and hereditary. • Over 200 types of abnormal hemoglobin, most very rare. • Most common in persons of African descent (1/500 have disease; 1/12 carry the gene). • Also seen in persons of Mediterranean, Arabic, and South Asian ancestry.
Three most common hemoglobin disorders
• Sickle Cell Anemia: Most common form. Usually diagnosed shortly after birth; peak in death rate at ages 2-5 due to hindered ability to fight disease. Becomes milder as individual ages. Person has an elongated, thin appearance; growth usually stunted. • Hemoglobinopathy SC: May not show symptoms until adolescence/adulthood. Mortality peaks at ages 40-60, usually due to cardiovascular complications (arteriosclerosis) • Thalassemia: Two forms: One mimics sickle cell anemia and is more serious; the other mimics hemoglobinopathy SC and is less serious. ++++++++ Sickle Cell Trait: Individuals who carry one normal gene and one sickle cell gene usually show no symptoms, but may have some abnormal hemoglobin.
Sickle Cell Crises
• Distinctive manifestations of sickle cell disease. • Four Types: – Vaso-Occlusive or Painful Crisis: Sickle cells clog and block blood vessels, causing infarction of tissue. – Aplastic Crisis: Red blood cells are destroyed in the bone marrow as they are created, causing lowered blood count. – Splenic Sequestration: Spleen enlarges, trapping red blood cells in the organ, lowering blood count. – Hyperhemolytic Crisis: Increase in pace of destruction of red blood cells.
Other Complications
• Anemia • Jaundice • Cardiovascular concerns (heart murmurs, congestive heart failure, heart attack, stroke, arteriosclerosis). • Damage to bones (marrow destruction, loss of bone mass, osteoarthritis, osteomyelitis). • Pneumonia and pulmonary embolisms • Damage to internal organs • Damage to skin • Infections, esp. Encephalitis, Septicemia • Sexual Dysfunction (Priapism in men or continuous erection, causing damage to vascular structures).
Sickle Cell Disease: Treatment
• There is no cure for sickle cell disease. • Treatment:
– Transfusions in certain circumstances. – Avoidance of infections (can bring on sickle cell crisis) – Management of complications
• Prevention (Genetic Counseling)
Sickle Cell Disease: Rehabilitation
• Disease is unpredictable; planning may be difficult. • Chronic fatigue is the major physical limitation. • Physical capacities vary widely--all persons with sickle cell can do sedentary/light work, but others may be able to perform medium to very heavy work. • Heavy lifting may cause complications in some persons. • Environment should be adequately oxygenated; not cold (increases cell sickling). • Disease causes thirst; person should have ready access to drinking water and toilet. • Stress may bring about crises--may need to be avoided. • Complications of the disease can impose additional functional restrictions.
Hemophilia
• Hemophilia is an insufficient ability of the blood to clot, caused by a lack of one or more of 13 clotting factors present in the blood. • Two major types: – Hemophilia A (Classic Hemophilia): Lack of clotting factor VIII; accounts for 80% of cases – Hemophilia B (Christmas Disease): Lack of clotting factor IX; accounts for 19% of cases. • Hemophilia A and B are caused by a sex-linked inherited gene and are seen only in males. Hemophilia in women is exceedingly rare and is only brought about as a result of a number of disorders such as Von Willebrand’s Syndrome, which make up 1% of hemophilia cases and can occur in either sex; some female carriers of hemophilia genes may show some mild symptoms.
Causes of hemophilia
• Inability to clot can make even minor wounds lifethreatening. • Hemoarthroses: Spontaneous bleeding in the joints; causes swelling, pain, loss of range of motion. Can lead to osteoarthritis. • Risk of hemoarthroses can make exertion and prolonged sitting/ standing difficult. • Treatment: Replacement of clotting factors with those derived from human donors.
– Can be done in the home. – Very expensive – Person is at heightened risk of developing blood-borne diseases and infections.
Hemophilia: Symptoms, Complications, Treatment
Hemophilia and Rehabilitation
• Sedentary and light work should be considered, although some persons can tolerate medium exertion. • Dangerous work should be avoided for obvious reasons. • Psychosocial implications: Children can grow up sheltered, overprotected; can be emotionally and vocationally immature.
Human Immunodeficiency Virus Spectrum
Note: HIV Spectrum is now the preferred term to refer to this disorder, rather than AIDS.
HIV and the Body
• The human immunodeficiency virus attacks the immune system by way of T-cells, rendering the body incapable of fighting off infections. • We are exposed to viruses, germs, and fungi which our immune system normally can fight off easily. • If the immune system is weakened, these organisms can easily infect the body, however.
Opportunistic Infections
• Pneumocystis Carinii pneumonia: Caused by a parasite common in the body. • Toxoplasmosis: Brain infection; Caused by microorganisms commonly carried by cats. • Oral Thrush/Candidiasis: Caused by candida fungus; painful, raised white blothches in mouth/throat. A form of yeast infection. • Kaposi’s Sarcoma: Opportunistic cancer, manifested in red or purple blotches in the skin.
Testing for HIV infection
• Opportunistic infection may indicate HIV infection; calls for testing
– ELISA test: Initial test for HIV.
– Western Blot: A confirmatory test administered if the ELISA test shows positive result for HIV infection.
Course of Disease
• Old classification:
– HIV infection showing no symptoms – AIDS-Related Complex (ARC): Bouts with opportunistic infections increasing in severity.
– AIDS/Full Blown AIDS: Massive infections leading to death.
Course of the Disease
• New classification, four groups based on tcell count: The HIV Spectrum
– 1: Evidence of recent infection (usually flu-like symptoms) – 2: Asymptomatic, but infected. – 3: Swollen lymph nodes over extended period of time. – 4. Opportunistic infections.
• There is no cure for HIV infection. Treatment attempts to support immune system, treat opportunistic infections. • HIV now may be regarded as a manageable disease in many persons, much like diabetes, because of new drug treatments. • Combinations of drugs (drug cocktails) have allowed persons to remain relatively symptom free for longer and longer periods of time. • Drug cocktails may have serious side effects (nausea, lethargy, development of abnormal facial fat).
Treatment of HIV
HIV: Rehabilitation Concerns
• HIV is an extremely difficult disease to catch. • Unreasonable fear and loathing remain the greatest obstacles to employment for persons with HIV. • Persons with HIV may have no functional limitations for many years--often, no rehabilitation is needed. • As disease progresses, and individual becomes more ill, functional limitations will be present. Often, these may be so severe or swift as to prevent the individual from participating in rehabilitation. • HIV may more often be a secondary concern in rehabilitation, rather than a primary disability. • Persons in rehabilitation who have HIV should avoid crowds and be cautious if employed in health care occupations--not because they can infect others, but because others might infect them with communicable diseases.