Pathophysiology

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Sickle Cell Anemia

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Sickle Cell Anemia is an inherited disease characterized by periods of relative health alternating with episodes of severe illness caused when sickle shaped [pic]red blood cells block small blood vessels. According to the encyclopedia here’s the pathophysiology of the disease; Sickle cell anemia is caused by a mutation in the B globin chain of hemoglobin, causing the amino acid glutamic acid to be replaced with the hydrophobic amino acid valine at the sixth position. The B globin gene is found on the short arm of chromosome 11. The association of two wild type A globin subunits with two mutant B globin subunits forms hemoglobin S. Under low oxygen conditions, the absence of a polar amino acid at position six of the b globin chain promotes the non covalent polymerization (aggregation) of hemoglobin, which distorts red blood cells into a sickle shape and decreases their elasticity. The loss of red blood cell elasticity is central to the pathophysiology of sickle cell disease. Normal red blood cells are quite elastic, which allows the cells to deform to pass through capillaries. In sickle cell disease, low oxygen tension promotes red blood cell sickling and repeated episodes of sickling damage the cell membrane and decreases the cell 's elasticity. These cells fail to return to normal shape when normal oxygen tension is restored. These rigid blood cells are unable to deform as they pass through narrow capillaries, leading to vessel occlusion and ischemia (a restriction in blood supply). Sickle cell anemia is a genetic disorder that causes the victim 's red blood cells to become stiff and sickle shaped. The disease causes a variety of symptoms, the most prominent of which are crises, caused when the deformed cells block small capillaries, preventing the flow of oxygen to limbs and organs. This blockage is called sludging. The crises range from mild bone aches to devastating body pain and can last up to a week. In the most severe cases, stroke can occur. Currently, there is no cure for [pic]the disease. A child with sickle cell anemia has inherited one duplicate of the defective gene from each parent. Two sickle cell carriers have a 25% chance of having a child with sickle cell and a 50% chance of having a child with the defective gene. In the United States, the illness is common among African Americans, although people of Middle Eastern, Mediterranean, and Indian descent are also at risk. One of every 10 black Americans carries a single gene for sickle cell anemia, one in every 500 (50,000-70,000 people) carries two genes and therefore suffers from [pic]the disease. Those at risk can be tested for the presence of the gene. A hemoglobin electrophoresis test determines if someone is a carrier, and amniocentesis can detect the presence of sickle cell anemia in a fetus. Newborn screening is mandated in approximately 40 states and can be requested if not done routinely.

Symptoms of sickle cell anemia usually appear when the child is about three months old. The child will suffer from painful swelling of the hands or feet. By one year of age the child may refuse to walk. During the first five years of life, infection is a primary concern, mainly if sludging occurs in the spleen, preventing it from filtering out bacteria. Parents should be alert for any signs of infection, such as fever, poor feeding, bad temper, vomiting, and diarrhea. If infection is present, antibiotics are needed to fight off possible fatal complications.

After the age of five, most children have acquired a number of natural immunities, and the danger of infection lessens. During the early school years, the sickle cell patient will experience periodic sludging in the large bones of the body. In youth the danger of complications returns as major organs become prone to sludging. During crises, blood can pool in the spleen and destroy its tissue. Sickle cell victims may also have enlarged hearts. Teenagers with sickle cell are generally two to four years behind in physical development, which can be a source of anxiety to young people. Young women with sickle cell anemia usually do not suffer from infertility, but any pregnancy should be handled with care.

Aggressive research and treatment in recent years have made it possible for sickle cell anemia patients to live long and productive lives. For young children, a pneumococcal vaccine and antibiotic therapy is recommended. When sludging episodes are mild, the child can be made comfortable with over the counter pain medications, rest, and fluids. More severe crises may require hospitalization for stronger pain relief such as spinal anesthetics. Blood transfusions also offer temporary relief from sludging crises. Although bone marrow transplants have been effective in a few very rare cases, the procedure is still under study as a possible cure for [pic]the disease. Transplants carry a 10% risk of death and the drugs used to destroy the old bone marrow can result in infertility.

I conclude that the sickle cell population has a challenging task to deal with this disease. The pain of the disease is not just physical, but can be emotional and psychological too. Due to the complexities of the disease that can affect these individuals, social workers need to work efficiently and effectively with each aspect of the individual’s life and allow the families to do the same on needy basics for their love one.

Bibliography

| |Sickle Cell Disease In Children And Adolescents: Diagnosis, Guidelines For Comprehensive Care, And Care Paths And Protocols For |
| |Management Of Acute And Chronic Complications Peter A. Lane Sedona, AZ, November 10-12, 2001 |

Understanding Sickle Cell Disease: A Handbook for School Personnel http://www.vahealth.org/sicklecell/docs/SchoolHandbook_SickleCellChild

www.google.com

Britannica Online Encyclopedia

Bibliography: | |Sickle Cell Disease In Children And Adolescents: Diagnosis, Guidelines For Comprehensive Care, And Care Paths And Protocols For | | |Management Of Acute And Chronic Complications Peter A. Lane Sedona, AZ, November 10-12, 2001 | Understanding Sickle Cell Disease:  A Handbook for School Personnel http://www.vahealth.org/sicklecell/docs/SchoolHandbook_SickleCellChild www.google.com Britannica Online Encyclopedia