Sickle cell anemia is a disease that can be inherited and can affect the structure of a red blood cell. This causes a ripple effect throughout the body because blood contains hemoglobin: a protein that carries oxygen around the body. This illness has challenged researchers in search of cures and treatments, and only a few are known to be effective today.
A normal blood cell appears as a smooth, flexible donut-like shape without a hole in the middle. Alternatively, sickle cell blood cells are in the shape of a letter C or crescent because it is depleted of all of its oxygen and hemoglobin. Inheriting two genes, one from each parent, of a hemoglobin “S” (an abnormal form of hemoglobin), tends to cause rigid structured red blood cells. This is the strongest degree of sickle cell disease among the multiple possible varieties depending on the abnormality of the hemoglobin gene. Another possibility includes a person who inherited one normal gene and one abnormal gene for hemoglobin, also referred to as a carrier for the trait. These carriers are at a higher risk of having children with sickle cell disease. So, what is the big deal with this disease and why is it notoriously harmful?
Sickle cell anemia is thought to have originated in Africa thousands of years ago in hopes of helping protect the population from malaria. Those carrying one copy of the sickle cell gene provided individuals with protection and resistance to certain malarial episodes. However, those with both of the genes unfortunately died because of too much of their hemoglobin being out of shape. This logic is what led researchers to believe that there was a certain selective pressure on the number of sickle cell genes that are protective, thus leading to its balanced prevalence in African-American and Hispanic populations. This would help explain why these groups of people are more prone to getting sickle cell anemia; more specifically, one out of every 365 African-American births and 1 of every 16,300 Hispanic American births results in some form of sickle cell anemia. A simple blood test can determine if an individual is a carrier of the trait, however cures for this anemia are still being researched as studies have shown only invasive and risky techniques as the most promising “cure” as of now.
Although it may seem like having blood cells in the shape of sickles or crescents is not very harmful to the human body, it has been shown to be fatal in some cases and in less extreme situations to impact the spleen, brain, bones, kidney, or heart. The problem with the sickle shape of these blood cells is that they die off very quickly due to the structural damage, leaving the body with a constant shortage of blood and high stress to create more. In the scenario that the blood cells are functioning, without the correct structure of the hemoglobin the blood cell becomes very rigid and sticky which often slows or blocks blood flow. This clotting is extremely problematic since it causes pain and can result in serious complications such as acute chest syndrome and possibly even a stroke. Clotting is also responsible for the other symptoms that accompany this anemia including swelling of the hands and feet, frequent infections, delayed puberty, and vision problems.
Treatment for this disease began back in the 1960s when blood transfusion was first used to treat sickle cell anemia. In a blood transfusion, red blood cells are removed from the donated blood and given through the veins to the patient. The increase of healthy blood cells reduces complications within the individual as well as decreases the pressure to make more blood cells. This treatment method has been proven successful for some severe cases of sickle cell anemia and reduces the risk of complications that accompany this disease. Additionally, It may prevent a stroke in childrenas well. Although seemingly effective, it does have risks such as high levels of iron, mismatched blood type, threat of transmitted disease through Blood, Etc. Furthermore, this is a preventative method and not a cure, making this treatment less appealing.
Medication is another way that sickle cell disease can be managed. Some of the weaker medicines reduce the frequency of pain and need for blood transfusions while the stronger ones can lower the risk of anemia and improve blood flow throughout the body. Side effects of these medications include nausea, joint pain, fever, back pain, and can increase the risk of infection, diarrhea, rashes, and fatigue. While these can be an effective temporary solution, none of these can completely cure an individual.
Finally, more invasive techniques such as stem cell transplants, stem cell gene addition therapy, and gene editing therapy may be able to completely cure a patient with this disease. Stem cell transplant, more commonly known as bone marrow transplant, is an invasive procedure involving replacing the bone marrow affected by sickle cell anemia with donated bone marrow. The risk of this procedure is high, including death, thus it should only be performed for young children experiencing extreme side effects and not for patients with milder conditions. Another stem cell option could be Gene addition therapy: the process of removing the patient’s stem cells, inserting the gene for healthy hemoglobin production, and giving back the stem cells to the patient. This option is best suited for patients who do not have a well-matched donor. Although there are risks to this process, it can be a cure if done correctly.
Individuals with sickle cell anemia can take steps to try to avoid the many complications that accompany this disease. For example, drinking water, avoiding extreme temperatures, exercising regularly, avoid smoking, using medication, and a healthy diet are all factors that can reduce complications and improve one's chances of living a longer, healthier life. As of December 2023, the FDA has approved two gene therapies that may become potential cures for those with severe sickle cell anemia and more curative therapies that don't involve stem cells are currently being researched. This may just be the end of the sickle cell anemia reign with all promising research in work.
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