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Disorders
of the Blood and Immune System
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Blood dyscrasias are disorders that affect the blood or the structures in the body that manufacture blood components. The disorders may develop independently or as a complication of other disorders.
ANEMIA
Anemia is the term used to describe a reduced red blood cell count in the blood or weakened hemoglobin in the blood. Lowered red blood cell counts reduce the amount of oxygen and nutrients that can be carried to the cells, and thereby affect the amount of physical exertion an individual may tolerate. Individuals with anemia are short of breath, male appear pale, have increased heart rate and may feel mentally and physically exhausted. There are a variety of different forms of anemia. Aplastic Anemia is a result of malfunction of the bone marrow. Hemolytic Anemia is the state in which red blood cells are destroyed faster than the body can replace them. Other forms of anemia are due to mineral deficiencies or faulty metabolism. In this category are Iron Deficiency Anemia, caused by poor iron intake or difficulty in the metabolism of iron; and Pernicious Anemia, caused by difficulties in the body’s ability to metabolism vitamin B12. Treatment of anemia is aimed at the cause. If it is underlying disease, improvement in this area will improve the red blood count. Dietary improvements may also be of benefit. Transfusions may be necessary until the body can manufacture an adequate supply of red blood cells.
POLYCYTHEMIA
Polycythemia is an overabundance of red blood cells. The increase in the number of red blood cells thickens the blood and makes it more difficult for the body to pump the blood through the blood vessels, which can lead to a number of cardiovascular problems such as stroke, heart attack, high blood pressure, and congestive heart failure. Like other blood dyscrasias, polycythemia may develop independently or as a complication of other disorders, and treatment may focus on improving the underlying medical cause. Efforts to thin the blood, such as increasing fluid intake, are also attempted.
AGRANULOCYSTOSIS
Agranulocystosis is a reduction in the count of neutrophils, a certain type of white blood cell. The disorder is a medical emergency and can quickly result in death due to a decreased ability to fight infection. The disease is often caused by exposure to poisons of some type, and treatment involves removal of the causal agent as well as massive doses of antibiotics to prevent infection.
REHABILITATION CONSIDERATIONS
These disorders will likely impose few if any functional limitations if brought under control. Persons with active blood dyscrasias likely will see a decrease in mental and physical vitality. The disorders often develop secondarily to other serious medical conditions, and these disorders will necessitate additional functional limitations on the individual.
Sickle cell diseases are a special group of blood dyscrasias in which blood cells deteriorate rapidly and assume a disfigured shape, often the shape of a sickle. Sickle cell diseases are hereditary in nature and are most common in persons of African ancestry (1/12 are carriers of the gene; one in 500 has the disease). The disorder also occurs in persons of Mediterranean, Arabian, and Southern Asian descent. It is speculated that the sickle-cell trait developed as an adaptation to malaria, which is more common in warmer and tropical climates.
To understand the effect of sickle cell diseases, the function of normal red blood cells must first be discussed. Normal red blood cells are rounded and carry normal hemoglobin. These cells carry oxygen and nutrients to the cells of the body until destroyed by the spleen, and have a life span of about 120 days. Old blood cells are converted into amino acids, with a small portion turned into bile by the liver.
Sickle cells are caused by faulty hemoglobin, which rapidly breaks down in the oxygenation/deoxygenation cycle. As the cells break down, they assume the sickle shape and cannot carry oxygen as efficiently. The cells break down more quickly, and have a life span of one to two weeks. Because red blood cells are broken down more quickly, the liver will overproduce bile and the individual will become jaundiced (have a yellow pallor in the skin). Sickle cell diseases may also bring on a wide variety of other complications.
There are over 200 varieties of abnormal hemoglobin, the vast majority of which are very rare. Three types of abnormal hemoglobin are responsible for the greater part of sickle cell diseases. These are Sickle Cell Anemia, Hemoglobinopathy SC, and Thalassemia.
SICKLE CELL ANEMIA
Sickle Cell Anemia is the most common form of sickle cell disease. It is usually diagnosed shortly after birth with a peak in mortality between ages 2 and 5 due to a hindered ability of the body to fight the infections related to the disease. The disease tends to become milder as the individual passes from childhood to adolescence and adulthood. Persons with Sickle Cell Anemia have a elongated, thin appearance with retardation of growth. Individuals display the rapidly deteriorating sickled red blood cells.
HEMOGLOBINOPATHY SC
Hemoglobinopathy SC (sickle cell) is a milder form of sickle cell disease. It is about a third as prevalent as sickle cell anemia and may not show symptoms until adolescence or early adulthood. Mortality peaks between ages 40 and 60 and is often due to arteriosclerotic heart disease.
SICKLE THALASSEMIA
Sickle thalassemia may take one of two forms. The milder form mimics Hemoglobinopathy SC in symptoms and complications, and the more severe form mimics sickle cell anemia.
SICKLE CELL TRAIT
The sickle cell trait is present in individuals who have one normal gene and one sickle cell gene. Sickle cell trait does not normally cause problems, although individuals may have some abnormal hemoglobin in the blood stream. The sickle cell trait should be identified through genetic testing and counseling to prevent development of sickle cell diseases in offspring.
SICKLE CELL CRISES AND COMPLICATIONS
Sickle Cell Crises are distinctive manifestations of sickle cell diseases. There are four types of sickle cell crises. The first of these is the Vaso-Occlusive or Painful crisis, in which blood vessels are clogged by the elongated sickle cells, cutting off blood supply and causing clusters of cells to die, or infarct. The symptoms of this crisis usually are deep-seated, severe aching which is either generalized or localized. The second type of crisis is referred to as the Aplastic crisis, in which red blood cells in the process of creation are destroyed in the bone marrow, lowering the level of operating hemoglobin in the bloodstream. The crisis is often secondary to a viral infection. Splenic Sequestration is a disorder most common with sickle cell anemia, is brought on by infection, and involves an enlargement of the spleen which causes red blood cells to become trapped in the organ, lowering the blood count. The Hyperhemolytic Crisis is an acceleration in the pace of red blood cell destruction and delayed replacement, and may be caused by infections or reactions to certain kinds of chemicals or other substances.
Complications of sickle cell diseases are numerous. Anemia is common, with enlargement of bone marrow and thinning of bone mass, increased workload of the heart, and jaundice from increased rate of destruction of red blood cells. Heart problems, including murmurs, enlargement of the heart and congestive heart failure, and myocardial infarction may occur. The lungs are affected, and the individual with sickle cell disease may be prone to pneumonia and pulmonary embolisms originating in the bone marrow. Bone diseases, including arthritis, thinning of the bones in the hands, feet, and the heads of the femurs, and osteomyelitis may develop. Strokes and cerebral hemorrhage are more likely to occur. Infections, especially serious diseases such as encephalitis and septicemia, are more likely to develop, especially in children with the disease. Damage to internal organs, to the skin (especially the skin of the legs), and sexual dysfunction are also common complications. Many of these complications are due to infarcts in various parts of the body that result from reduced blood flow from the sickle cells clogging blood vessels.
TREATMENT
There is no cure for sickle cell anemia, and treatment is limited to management of complications and sickle cell crises. This often involves treatment of infections that may bring on crises as well as blood transfusions to increase the amount of working hemoglobin in the blood stream.
REHABILITATION CONSIDERATIONS
The major functional limitation specific to sickle cell disease, like other blood dyscrasias, is chronic fatigue. The risk of sudden death is small in adults. However, the diseases are unpredictable and can make rehabilitation planning difficult. Sickle cell anemia will usually cause greater problems than other forms of the disease. The complications of the disease also will impose their own functional limitations.
Physical capacities can vary widely. Sedentary and light work can be performed by all persons with sickle cell disease, and some individuals able to perform medium to very heavy work. However, heavy lifting may aggravate certain complications of the disease in some individuals and should be avoided in these cases. The individual with the disease is often the best source of information as to physical capabilities.
Environmental considerations can be critical in sickle cell diseases. Heat and humidity will increase fatigue, and cold temperatures can accelerate cell sickling. Deoxygenated environments (high altitudes, caisson work) should be avoided due to the difficulty of the blood cells to carry limited oxygen supplies. Access to drinking water and a restroom should be considered, as sickle cell patients require more than the normal amount of fluid intake. Stress is known to exacerbate the disease in most persons, and stressful work may not be a wise consideration.
Hemophilia is a congenital disorder in which the absence of a factor in the blood causes disorders in blood clotting. When the skin is broken the body responds in two ways through the blood. First, the platelets will form a “plug” in the wound. Then, clotting factors (there are 13 in normal blood) interact with the platelets to close the wound and begin the healing and regenerative process.
There are two prominent types of hemophilia which differ in the clotting factor which is missing. Hemophilia A (also called classic hemophilia) involves the lack of clotting factor VIII, and is the most common form of the disease (80% of cases). Hemophilia B (also called Christmas disease) is the lack of clotting factor IX and accounts for 19% of hemophilia cases. Hemophilia A and B are sex linked hereditary conditions that are found only in males. Hemophilia in women is exceedingly rare, and is caused only by diseases such as Von Willebrand’s Syndrome and other rare diseases that together make up only 1% of hemophilia cases.
The inability of the blood to clot causes obvious problems with wounding. Another severe problem of hemophilia are hemoarthrosies, or spontaneous bleeding in the joints of the body which limit range of motion, and make exertion and prolonged standing and sitting difficult. Treatment of the disorder involves intravenous administration of the missing clotting factors, which must be taken from human donors. The treatment can be done in the home, much like hemodialysis or injection of insulin. The clotting factors are extremely expensive, and financial distress is a common problem for people with hemophilia. Because human blood products are used in treatment, individuals with hemophilia are at increased risk of contracting blood borne diseases.
REHABILITATION CONSIDERATIONS
Persons with hemophilia may grow up sheltered, overprotected, and may not have had access to the normal developmental experiences. This can lead to emotional and vocational immaturity, and the rehabilitation counselor working with a person with hemophilia should be aware of these potential psychosocial implications. Persons with hemophilia are best employed in sedentary or light work; some persons may be able to tolerate medium exertion. Because of the nature of the disease, dangerous situations should be avoided.
The Human Immunodeficiency Virus (HIV) Spectrum is currently the preferred term in referring to the effects of HIV on the body. The HIV virus affects the T-cells of the immune system, rendering it ineffective in preventing infections in the body.
Each of us is frequently (if not constantly) exposed to a number of bacteria, parasites, and fungi that ordinarily do not infect us because of the work of the immune system. Because the immune system is compromised in HIV infection, these organisms are allowed to grow and may become life threatening; these are called opportunistic infections. Two of the more common infections are pneumocystis carinii pneumonia, caused by parasitic infection, and candidiasis (yeast infection), caused by the Candida fungus and commonly manifested as oral thrush-painful white plaques in the mouth and throat. Certain cancers are also opportunistic in nature and may appear in HIV infection. The most common of these is Kaposi’s Sarcoma, manifested by red, blue or purple blotches under the skin. Neurological effects, ranging from headache to severe dementia, are also common in
Appearance of these disorders is an indication that an individual may have HIV infection. HIV infection is diagnosed through one of two blood tests: the ELISA test and the Western Blot. Multiple positive results on the ELISA test are confirmed with the Western Blot, indicating that an individual is indeed infected with HIV.
The course of the disease was once referred to in terms of asymptomatic HIV infection, followed by AIDS-related complex (increasing bouts with opportunistic infections and cancers) and finally full-blown AIDS, or massive infections leading to death. The proper terminology in describing HIV infection is now referred to as the HIV Spectrum. The spectrum has four stages (groups) which are progressive. The first group includes those that demonstrate symptoms of recent HIV infection (typically flu-like symptoms); the second group those who are infected with the virus but are asymptomatic; the third group those who demonstrate swelling of the lymph nodes for extended periods of time, and the fourth group those with opportunistic infections. The level of the T-cell count in the blood is lower as an individual passes through the four groups.
TREATMENT
HIV remains an incurable disease, but advances in medical treatment have allowed its course to be slowed and persons with HIV are living longer. Treatment is aimed at supporting the immune system for as long as possible and attempting to manage opportunistic infections should they appear.
REHABILITATION CONSIDERATIONS
Persons with HIV infection will likely have no significant functional limitations for a period of time that can last for years. The greatest problems with HIV and vocational adjustment remain the fear and loathing of others leading to discrimination in hiring and retention. HIV is a difficult disease to catch, as the virus is quite fragile, and typically has to get directly from the body fluids of an infected individual to the bloodstream of an individual that is not infected. Fears of spread of the disease in food service occupations, for example, are unfounded.
Persons with HIV might want to avoid crowds and it may be wise for them to work alone-not because they will infect other people with HIV, but rather because they may be exposed to infectious agents carried by others. In particular, work in health care settings such as hospitals may not be advisable.
As persons with HIV live longer with the disease, they will increasingly come to the attention of rehabilitation personnel. As the disease enters later stages of the spectrum, persons may experience increasing fatigue and other functional limitations that may necessitate job change or modification. If severe neurological symptoms develop, individuals with HIV may have problems with the thought process that can preclude employment.