Sickle cell disease

Definition

Sickle cell disease is a genetic blood disorder characterized by the presence of abnormal hemoglobin known as hemoglobin S, which causes red blood cells to take on a rigid, crescent or sickle shape. This distortion in shape affects the red blood cells' ability to transport oxygen efficiently and can lead to various complications such as pain crises, increased risk of infections, and organ damage, all of which relate to blood composition and hemodynamics.

5 Must Know Facts For Your Next Test

1. Sickle cell disease is inherited in an autosomal recessive pattern, meaning a person must inherit two copies of the sickle cell gene (one from each parent) to have the disease.
2. The sickle-shaped cells have a much shorter lifespan than normal red blood cells, typically lasting only 10-20 days compared to 120 days for healthy cells.
3. This disease is more prevalent among individuals of African, Mediterranean, Middle Eastern, and Indian descent due to evolutionary adaptations against malaria.
4. Sickle cell disease can lead to chronic complications such as organ damage, increased risk of stroke, and severe infections due to splenic dysfunction.
5. Management strategies include pain relief during crises, blood transfusions, and medications like hydroxyurea that help increase fetal hemoglobin production to reduce sickling.

Review Questions

• How does sickle cell disease affect blood composition and the hemodynamic properties of the circulatory system?
  • Sickle cell disease affects blood composition by altering the shape and function of red blood cells. The abnormal hemoglobin S leads to sickling, causing red blood cells to become rigid and sticky. This changes their flow dynamics within the circulatory system, increasing the likelihood of blockages in small blood vessels and causing pain crises due to reduced oxygen delivery to tissues. These hemodynamic changes can result in chronic complications as tissues become ischemic.
• Discuss how sickle cell disease can lead to anemia and its implications for oxygen transport in the body.
  • Sickle cell disease causes anemia due to the rapid destruction of sickled red blood cells. With a significantly shorter lifespan than normal red blood cells, patients often experience low levels of hemoglobin. This decrease in healthy red blood cells impairs the body's ability to transport oxygen effectively, leading to symptoms like fatigue, weakness, and increased heart rate. Consequently, individuals with sickle cell disease must manage their condition actively to mitigate these anemia-related issues.
• Evaluate the relationship between sickle cell disease and its associated complications within the broader context of public health.
  • Sickle cell disease presents significant public health challenges due to its prevalence in specific populations and its chronic nature. The complications associated with this disorder, such as frequent pain crises, increased susceptibility to infections, and long-term organ damage, place a heavy burden on healthcare systems. Effective management requires comprehensive care strategies including patient education, access to treatments like hydroxyurea or transfusions, and ongoing research into gene therapy options. The societal impact also includes addressing healthcare disparities for affected populations and improving overall quality of life for individuals with sickle cell disease.

Related terms

Hemoglobin: A protein in red blood cells responsible for transporting oxygen from the lungs to the rest of the body and returning carbon dioxide from the body to the lungs.

Anemia: A condition in which there is a deficiency in the number or quality of red blood cells, leading to reduced oxygen transport and resulting in fatigue and weakness.

Vaso-occlusive crisis: A painful episode that occurs when sickle-shaped red blood cells block blood flow in small blood vessels, leading to tissue ischemia and pain.