What Is Sickle Cell Disease?

Sickle cell disease is an inherited red blood cell disorder that causes hemoglobin to become irregularly shaped. Hemoglobin is a protein in red blood cells that delivers oxygen throughout the body. Normal red blood cells with hemoglobin are smooth, flexible and round. Sickle cell disease results in hemoglobin evolving into a sickle shape. They also become stiff and stick together, causing difficulty moving through blood vessels. Sickle cell disease can cause blockages in blood flow, resulting in anemia, pain, infections, organ failure, etc.

Types of sickle cell disease

The type of sickle cell disease depends on the genes inherited from parents. Common types include Hemoglobin SS, Hemoglobin SC, Hemoglobin beta plus, and Hemoglobin beta zero. Less common forms of sickle cell disease include Hemoglobin SD, Hemoglobin SE, and Hemoglobin SO. Although it is a lifelong condition, treatment options may improve symptoms.

Symptoms

Symptoms of sickle cell disease vary individually. They include, but are not limited to, the following:

• Jaundice (yellow pigment in the skin and whites of eyes)
• Anemia, which can cause paleness, fatigue and weakness
• Painful swelling in the hands and feet
• Frequent episodes of pain

Complications

Sickle cell disease can result in various health complications, which can be life-threatening. Complications may include the following:

• Stroke
• Pain crisis
• Acute chest syndrome
• Enlarged spleen caused by sickle cell pooling
• Blood vessel obstruction in the penis (priapism)
• Blood clots
• Vision problems
• Organ damage or failure

Causes

Sickle cell disease is caused by a genetic mutation in the HBB gene, which makes part of the hemoglobin. Individuals with sickle cell disease inherit the condition when each parent carries one copy of the mutated gene. However, they typically do not show signs or symptoms.

Risk factors

Certain groups are at an increased risk for developing sickle cell disease. They include the following:

• Those of African descent
• Those of Mediterranean, Middle Eastern, Indian, and Asian descent
• Hispanic Americans from South America and Central America