This article will help provide a basic understanding of sickle cell anemia. For the African American community, sickle cell disease is a major health issue. Sickle cell disease can also affect Mediterranean, Middle Eastern, and Asian Indian ancestry. There is a growing segment in the Latino-American population particularly those of Caribbean, Central American, and South American ancestry who are affected by this disease.
In the United States one out of every 400 births has this disease. The most common type of sickle cell disease is sickle cell anemia.
Definition and Description of Sickle Cell Disease
Sickle cell disease is a group of inherited blood disorders that center on red blood cells. These red blood cells can function abnormally resulting in small blood clots, chronic anemia, painful events, and potential complications associated with tissue and organ damage. These blood disorders include sickle cell anemia, Mediterranean blood disease, the sickle beta thalassemia syndromes, and hemoglobinopathies in which the sickle cell hemoglobin is in sufficient concentration to cause the red blood cell to sickle.
All types of sickle cell disease are caused by a genetic change in the hemoglobin portion of the red blood cell. Hemoglobin is the oxygen-carrying protein inside the red blood cell. Normal red blood cells are oval and flexible. Red blood cells in sickle cell disease have a tendency to reshape themselves into rod-like structures that resemble the curved blade of a sickle; thus, the term sickle cell.
Sickle cells have a shorter life span than normal red blood cells. This results in chronic anemia and reduced oxygen to the tissues of the body. Sickle cells are less flexible and more sticky than normal red blood cells. This presents a problem since they can be trapped in the small blood vessels preventing blood flow to the body’s tissues. This compromise in the delivery of oxygen to the tissues results in pain. It also has the potential to damage the associated tissues and organs.
Carriers of the sickle cell gene are referred to as having sickle cell trait. Most of the time sickle cell trait does not cause health problems. In fact, sickle cell trait can be beneficial because it provides protection against malaria, a disease caused by blood-borne parasites transmitted through mosquito bites. It is estimated that one in 12 African-Americans has sickle cell trait.
The Cause of Sickle Cell Disease!
The hemoglobin molecule of a red blood cell is made up of three components:
Sickle cells contain a genetic change in the beta globin component of the hemoglobin molecule. This is caused by a change in the genetic coding on chromosome 11. One small change in a single DNA nucleotide results in a different amino acid being inserted into the beta globin protein of the hemoglobin molecule. This results in the unique properties of sickle cells. For simplicity we will call this altered gene the “sickle cell gene” and the regular gene the “normal red blood cell gene.”
For most individuals, they have two copies of the “normal red blood cell gene” to produce normal beta globin resulting in typical red blood cells. Individuals with sickle cell trait have one “normal red blood cell gene” and one “sickle cell gene” so they produce both normal red blood cells and sickle cells in roughly equal proportions. Because of this they do not usually experience significant health problems as a result of having sickle cell trait. Those with sickle cell anemia have two “sickle cell genes.”
Genetics play a significant role in both the disease, symptoms, and in family planning. If both members of a couple have sickle cell trait, then there is a 25% chance in each pregnancy for the baby to inherit two sickle cell genes. The resulting child will have sickle cell anemia. Correspondingly, there is a 50% chance the baby will have sickle cell trait and a 25% chance that the baby will have the “normal red blood cell genes”.
If both members of a couple have sickle cell anemia, then the baby will have sickle cell anemia 100% of the time. If one member of the couple has sickle cell anemia and the other has both “normal red blood cell genes”, then the resulting child will have sickle cell trait 100% of the time. Finally, if one member of the couple has sickle cell trait and the other has both “normal red blood cell genes”, then the resulting child has a 50% chance of have normal red blood cell hemoglobin or a 50% chance of having sickle cell trait.
The Need for Oxygen!
Oxygen is necessary for life and the optimal function of all cells. Red blood cells transport the oxygen from your lungs to the tissues of your body. It is the hemoglobin molecule that binds oxygen to itself in the lungs. It then releases oxygen to the tissues for proper cell respiration. However, once the oxygen is released by the sickle cell hemoglobin it can cause the red blood cell to alter its normal oval shape into the rigid, sickle shape characteristic of sickle cells. Low oxygen can be a trigger for this change. Studies also seem to indicate that cold temperatures and dehydration can be additional factors in triggering this change.
Normal red blood cells can survive for approximately 120 days where as sickle cells typically last 10-12 days. This is an important factor because it leaves the bloodstream chronically short of red blood cells and hemoglobin which leads to anemia. This creates its own shortage of oxygen which could trigger a shape change in the oval red blood cell to the sickle shape. This rigid, sickle shape does not allow the sickle cell to fit well through small blood vessels.
In addition, there are altered chemical properties that develop which increases the cells’ “stickiness”. This is why sickle cells tend to adhere to the inside surfaces of small blood vessels, as well as other blood cells, resulting in blockages. These blockages prevent oxygenated blood from reaching the tissues resulting in pain. If kept without oxygen long enough possible organ and tissue damage can occur.
Common symptoms for those with sickle cell anemia include the following:
For those with sickle cell anemia, the severity of symptoms varies widely and cannot be predicted solely on genetic inheritance. Some with sickle cell anemia develop health and life threatening problems in infancy while others only have mild symptoms throughout their lives. Others experience various degrees of health issues as they age. Certain variations of sickle cell disease tend to have less severe symptoms than other types of sickle cell disease.
Organs Affected by Sickle Cell Anemia
Various organs and body systems can be effect by sickle cell disease. As you will see from this list, sickle cell anemia has a wide range of effects on the body. The bottom line is that any tissue that needs oxygen and adequate blood flow can be at risk.
Diagnosis and Treatment
The inheritance of sickle cell disease or sickle cell trait cannot be prevented but it can be predicted so screening is recommended. If you exhibit symptoms, then contact your physician so that accurate tests can be done. These tests can determine if you carry the “sickle cell gene” and what level of risk you are at. For newborns, more than 40 states include sickle cell screening as part of the battery of blood tests. However, don’t just assume the test is done. You must always be proactive.
Hemoglobin trait screening is always a good choice for any person of a high-risk ethnic background especially if you are planning on having children. If you and your partner are found to have sickle cell or any other hemoglobin traits, then you might want to receive genetic counseling to better understand the risk of sickle cell disease for your offspring. There are various testing options available to you to help you in your planning.
There are various treatment options to help prevent some of the symptoms and complications of sickle cell disease. These treatment options can include:
As with any disease condition, you want to always work with a qualified health professional to develop a course of action that best fits your individual situation.
There is new research that shows a direct correlation between nitric oxide deficiency and symptom severity for those with sickle cell anemia. I will discuss this in my companion article “Sickle Cell Disease – 14 Helpful Steps!” This article discusses the latest research. It also provides 14 suggestions you can use to help those with sickle cell disease.
I hope this article has given you a better understanding of sickle cell disease. I encourage you to take the steps to educate yourself and any loved ones who may have this health issue. Together we can help empower them to take the necessary steps to improve their overall health and wellness.
Until next time, may we both age youthfully!
P.S. As a convenience, below are the links to:
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