Friend or Foe: Hydroxyurea & Sickle Cell Anemia

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Morgane Kapto

ENGL 21003: Writing for the Sciences

Professor Williams

February 26, 2025

Imagine trying to go about your daily life, but every little task seems harder. The simple task of getting out of bed is a struggle, as you feel dizzy and out of breath. The act of making breakfast takes a while as you battle extreme tiredness, despite getting a full night’s sleep. Getting through the day is a hassle as you’re plagued with a fever and intense swelling of your hands and feet. The scene I just described gives you an idea of what the average person suffering from sickle cell anemia experiences, a collection of different symptoms (U.S. Department of Health and Human Services [USDHHS], 2024a). On the positive side, the drug Hydroxyurea reduces these symptoms and can improve the quality of life of those affected, however, it comes with its own caveats.

Sickle cell anemia is a lifelong disease that affects more than 100,000 people in the United States, and 8 million people worldwide (USDHHS, 2024b). It is an inherited disease that manifests when two copies of the mutation are present, one copy received from each parent. The mutation affects hemoglobin, a major component of red blood cells, which makes up the bloodstream and transports oxygen throughout the body. A healthy individual’s red blood cells are disk-shaped, but an anemic individual’s red blood cells are misshapen, a shape similar to a crescent or “sickle,” hence the name. Due to the deformed red blood cells, they are unable to carry out their duty of transporting oxygen, and so anemic patients are low on oxygen, which results in many other issues. People who have sickle cell disease go through bouts of intense pain called “pain crises,” which is caused by blockages in the bloodstream. They may also suffer with serious health complications like stroke, lung problems, eye problems, infections, and kidney disease (USDHHS, 2024b). Sickle cell anemia predominantly affects the Black population, with 9 out of 10 people affected by the disease identifying as Black or of African ancestry, and 1 out of 365 Black babies being born with the disease in the United States (USDHHS, 2024b). 

It is understood that the disease developed as a way to fight malaria, which is prevalent in Western Africa, as is sickle cell anemia. Malaria, a life threatening parasitic disease that spreads through mosquito bites, operates by infecting red blood cells and spreading throughout the body (Crutcher, 1996). When red blood cells are “sickled,” it is harder for the parasite to infect red blood cells, thereby containing the spread. From an evolutionary standpoint, it is more advantageous to carry the trait, or one copy of the gene, of sickle cell anemia to protect against malaria. However, it is not helpful to have the disease itself, or two copies of the gene, as its protection against malaria does not outweigh the symptoms of sickle cell anemia. 

Luckily, a treatment was made available in the 1980s to reduce symptoms of sickle cell anemia and increase longevity. Hydroxyurea is an antimetabolite, which inhibits normal metabolic (life supporting chemical processes) functions, and it helps prevent the formation of sickle-shaped red blood cells (U.S. National Library of Medicine [USNLM], 2024). Hydroxyurea is also used to treat cancer, but it is used in lower doses to treat sickle cell anemia (American Society of Hematology, n.d.). The treatment comes in the form of a capsule or tablet and is usually taken daily. 

When discussing a treatment, it is important to consider how it was made. In this case, Hydroxyurea was developed with the help of HeLa cells. HeLa cells are a line of cells that were unethically taken from an African American woman named Henrietta Lacks in 1951 (USDHHS, 2022). HeLa cells are considered to be immortal because the cells could reproduce on their own when they were cultivated outside of Henrietta Lacks’ body. The ethical issue surrounds how the HeLa cells were acquired. They cut a piece of Lacks’ tumor, and sent it to the lab for testing, as per the usual procedure. However, the health professionals did not tell Lacks or her family that she had cancer or that they would be using her cells for research. Since then, HeLa cells have been used for many scientific advancements, and are still used today. In developing Hydroxyurea, the treatment’s potential benefits were tested on HeLa cells in 1964, and it was noted that it was effective in slowing down cancerous growth and preventing the mis-shaping of red blood cells (USDHHS, 2022). 

Despite its effectiveness as a treatment for sickle cell anemia, Hydroxyurea does cause many side effects. It can be lethal at high doses, can increase the risk of infection and bleeding, and cause nausea, fever, shortness of breath, ulcers, and a fast heartbeat, to name a few (USNLM, 2024). For this reason, scientists have been searching for other treatments for sickle cell anemia, such as gene therapy. One gene therapy involves adding a modified gene to the body, and another involves making changes to a gene already in the body (USDHHS, 2024b).

There are many valid reasons as to why people may be hesitant to take Hydroxyurea or other treatments to help with sickle cell anemia. The United States has had a history of taking advantage of minorities, specifically Black Americans, and using them as medical test subjects. This structural racism, discrimination done by institutions, was prevalent in the development of Hydroxyurea itself, with Johns Hopkins Hospital using Henrietta Lacks’ cells for research purposes and sharing them without her or her family’s permission. This event along with other instances of medical abuse in the Black community justifies the apprehensions that people hold about medications, especially Hydroxyurea, which was created to deal specifically with a disease prevalent among Black people. However, many studies have been done confirming the drug’s safety at low doses, with over 30 years of evidence that Hydroxyurea is safe and effective for treating sickle cell anemia (McGann & Ware, 2015). One study discussed how the treatment could be used earlier in childhood to allow affected children to live longer and healthier lives (McGann & Ware, 2015).

All in all, Hydroxyurea remains a common treatment prescribed to those affected by sickle cell anemia to deal with their symptoms. Despite its drawbacks, when proper precaution is taken, Hydroxyurea is successful in alleviating the physical struggles that come with the disease. Getting out of bed becomes easier, making breakfast is a painless process, and the day becomes more manageable as one doesn’t have to deal with the fatigue, nausea, or pain crises. Perhaps in the future we will see better and improved treatments for sickle cell anemia, but for now, many are grateful for Hydroxyurea today.

References

American Society of Hematology. (n.d.). Sickle cell disease. Hematology.org. https://www.hematology.org/education/patients/anemia/sickle-cell-disease 

Crutcher, J. M. (1996, January 1). Malaria. Medical Microbiology. 4th edition. https://www.ncbi.nlm.nih.gov/books/NBK8584/ 

McGann, P. T., & Ware, R. E. (2015). Hydroxyurea therapy for sickle cell anemia. Expert opinion on drug safety, 14(11), 1749–1758. https://doi.org/10.1517/14740338.2015.1088827

U.S. Department of Health and Human Services. (2022, October 3). Significant research advances enabled by Hela Cells. National Institutes of Health. https://osp.od.nih.gov/hela-cells/significant-research-advances-enabled-by-hela-cells/ 

U.S. Department of Health and Human Services. (2024a, August 20). Symptoms. National Heart Lung and Blood Institute. https://www.nhlbi.nih.gov/health/sickle-cell-disease/symptoms 

U.S. Department of Health and Human Services. (2024b, September 30). What is sickle cell disease? National Heart Lung and Blood Institute. https://www.nhlbi.nih.gov/health/sickle-cell-disease 

U.S. National Library of Medicine. (2024, October 20). Hydroxyurea: Medlineplus drug information. MedlinePlus. https://medlineplus.gov/druginfo/meds/a682004.html#:~:text=Hydroxyurea%20is%20in%20a%20class,sickle%2Dshaped%20red%20blood%20cells.