Sickle Cell Anemia Definition and Term Paper
- Length: 11 pages
- Subject: Disease
- Type: Term Paper
- Paper: #9653958
Excerpt from Term Paper :
Another symptom that is often found is a yellowing of skin and eyes; this is a sign of jaundice due to the breakdown of red blood cells. Another sign is that children may show delayed growth and development. (Genetic Disease Profile: Sickle Cell Anemia)
One of the aspects that problematizes this disease are the complications that can arise as a result of the lowering of body defenses and the increased vulnerability to illness. This can be ascribed to spleen damage. The disease "....prevents the spleen from destroying bacteria in the blood. Infants and young children, especially, are susceptible to bacterial infections that can kill them in as little as 9 hours from onset of fever." (Genetic Disease Profile: Sickle Cell Anemia)
Stroke is anther serious possible consequence of this disease. This can result from defective cells damaging the walls of red blood vessels.
6. Brief historical overview.
While the HbS gene is usually found in Africa, yet there is very little evidence and reporting of this gene in African medical literature until the 1870s.
One reason given for this is that many of the symptoms of sickle cell anemia are similar to other diseases found on the continent. (Sickle Cell) Therefore most of the reports and published documentation about the disease are related to studies of patients in the United States.
One of the very first published medical papers on this disease was, "Case of Absence of the Spleen" in the Southern Journal of Medical Pharmacology, published in 1846 in America. (Sickle Cell)
However one of the first modern formal reports on the disease was published in Chicago 1910. This report was to establish the name of the disease. "In the western literature, the first description of sickle cell disease was by a Chicago physician, James B. Herrick, who noted in 1910 that a patient of his from the West Indies had an anemia characterized by unusual red cells that were "sickle shaped." (A Brief History of Sickle Cell Disease)
The following are some of the most significant events related to the historical study and research of sickle cell anemia.
Taliafero and Huck first recognized that the sickling phenomenon was an inherited condition in 1923. (Ingram 38)
In 1927, Hahn and Gillespie showed that sickling of the red cells was related to low oxygen. (A Brief History of Sickle Cell Disease)
In 1948, using a new technique known as protein electrophoresis, Linus Pauling and Harvey Itano showed that "...the hemoglobin from patients with sickle cell disease is different than that of normals. This made sickle cell disease the first disorder in which an abnormality in a protein was known to be at fault." (A Brief History of Sickle Cell Disease)
In 1949, Neel and Beet, independently, put forward the now accepted view that individuals with the severe sickle cell anemia were homozygous for an abnormal gene and that sickle-cell trait carriers were heterozygous, having one normal and one abnormal gene." (Ingram 38)
In 1956, sickle cell disease became the first genetic disorder whose molecular basis was known. This was achieved by Vernon Ingram and J.A. Hunt who "...sequenced sickle hemoglobin and showed that a glutamic acid at position 6 was replaced by a valine in sickle cell disease. Using the known information about amino acids and the codons that coded for them, they was able to predict the mutation in sickle cell disease. "(A Brief History of Sickle Cell Disease)
The first reported cure of sickle cell disease took place in 1984, when bone marrow transplantation in a child with sickle cell disease produced the first reported cure of the disease. "The transplantation was done to treat acute leukemia. The child's sickle cell disease was cured as a side-event. The procedure nonetheless set the precedence for later transplantation efforts directed specifically at sickle cell disease." (A Brief History of Sickle Cell Disease)
Another important breakthrough occurred in 1986 when a study found that "...young children with sickle cell anemia who took penicillin twice a day by mouth had much lower rates of S. pneumoniae infection than a similar group of children who received a placebo." (A Brief History of Sickle Cell Disease)
In 1987, a panel of experts recommended that "...all infants born in the United States be screened for sickle cell anemia so that children with the disease could be identified early and offered treatment with penicillin." (New Hope for People with Sickle Cell Anemia)
In 1995 a drug known as Hydroxyurea became the first and only drug that was successful in preventing various complications that could result from sickle cell disease. (A Brief History of Sickle Cell Disease)
7. Prognosis and treatment.
At present there is, except for bone marrow transplant, no known cure for sickle cell disease. However " Transplants are complicated procedures and aren't an option for everyone." (Sickle Cell Disease) Transplants often have extreme risk factors are also made problematic by donor matching and rejection issues. This is indicated in the following explanation of the dangers of this process. "First you give drugs to kill off the patient's marrow, then you do the transplant to replace the marrow. But the powerful drugs given to kill the patient's bone marrow can be dangerous for someone who has had a stroke or is at risk for stroke." (New Hope for People with Sickle Cell Anemia)
However, while there is as yet no definitive cure for this disease many studies point out that "...life expectancy for individuals with sickle cell anemia has improved." (New Hope for People with Sickle Cell Anemia) This is largely a result of early identification techniques and neonatal screening. Other factors such as penicillin therapy and early intervention have gone a long way to the alleviation of the more severe symptoms of the disease. "Improving treatment has raised lifespans into the 40's and rising. " (Prognosis of Sickle Cell Anemia)
As mentioned above, a recent breakthrough is the use of the drug Hydroxyurea. This has been found to be beneficial in treating the complications as well as the levels of pain in the sufferers of sickle cell anemia. However the full and long-term effects of this drug are not yet fully known and doctors only prescribe it under certain conditions. There are also a number of questions about its impact on the body and health that still need to be answered." Many questions about hydroxyurea in the treatment of sickle cell anemia remain unanswered...Doctors do not know what the most effective and least toxic dose of the drug is or whether taking it for many years presents health risks." (New Hope for People with Sickle Cell Anemia)
Gen therapy is an avenue that is being explored in the fight against this disease. The National Heart, Lung and Blood Institute (NHLBI) recently funded three centers to develop gene therapy for sickle cell anemia. As one medical expert states; "If you could replace the abnormal genes, you could cure the disease. However, there are significant technical problems involved in making gene therapy work." (New Hope for People with Sickle Cell Anemia)
Prehospital and EMS care and management of the disease are also factors that needs consideration. It is recommended that prehospital care is feasible when the severity of the disease is not extreme and "...self-treatment at home with bed rest, oral analgesia, and hydration is possible." (Anemia, Sickle Cell)
However if the situation worsens and the patient has to be transported by EMS, "...they should receive supplemental oxygen and intravenous hydration en route to the hospital," (Anemia, Sickle Cell) Prehospital management of sickle cell crisis should also include management of pain and involves the "... tailoring analgesics and dosages to the level of pain experienced by the patient, " as well as the "...administration of analgesics, including narcotics and NSAIDs, intracellular hydration with hypotonic fluids, bed rest, and antibiotics to treat underlying infection and other precipitants." (Paris et al. 2005)
The treatment and management of this disease has shown considerable advancement, which is evidenced by the decrease in the mortality rate. "In the past, individuals with sickle cell anemia often died in childhood. A 1973 study estimated that half of those with the disease died by the age of 14." (New Hope for People with Sickle Cell Anemia) This situation no longer applies and there is new hope for sufferers of this disease in the use of modern drugs, the increased awareness of the disease and the promise of gene therapy. There has also been research into the way that life habits can reduce the effects and complications of this disease. "...increasing knowledge about their specific effects on human development has led to various forms of environmental treatment: medications, diet, or a change in life habits. " (Pines 40)
Brief History of Sickle Cell Disease. May 31, 2006. http://sickle.bwh.harvard.edu/scd_history.html
Anemia, Sickle Cell. May 31, 2006. http://www.emedicine.com/EMERG/topic26.htm
Genetic Disease Profile: Sickle Cell Anemia. May 31, 2006. http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/sca.shtml
Sickle cell anemia. May 31, 2006. http://www.mayoclinic.com/health/sickle-cell-anemia/DS00324