Signs, Symptoms, and Complications
Sickle cell disease presentation is extremely variable. Some people may have mild symptoms, while others may experience severe symptoms and frequent complications. Infants with sickle cell disease are typically normal at birth, developing symptoms in their first year as hemoglobin F is replaced with hemoglobin S production. People with sickle cell disease due to homozygous Hb S (SS) are more likely to have severe symptoms than those with Hb S and Hb C (SC). Those with sickle cell trait are generally healthy but may sometimes have symptoms associated with sickle cell disease when they are exposed to intense exercise, dehydration, or changes in altitude, such as may be seen with athletes. Symptoms and complications of sickle cell disease may include:
- Pain crises. Episodes of pain that can last for extended periods of time are the most common complication of sickle cell disease. The pain is associated with the narrowing or obstruction of small blood vessels (called vaso-occlusion). This reduces or prevents blood flow to the affected area and can cause tissue damage. The location of the pain and its duration can vary from crisis to crisis and can occur throughout the body, especially in the bones, joints, lungs, and belly. Pain and swelling in the hands and feet is often one of the first symptoms noticed in young children. Decreased oxygen, infection, dehydration, a change in altitude, and temperature extremes can precipitate a pain crisis, but many occur without an identifiable trigger. The symptoms from each episode generally resolve in a few days to several weeks.
- Anemia is a common complication because of the shortened life of the sickled RBCs. Those affected may experience fatigue, decreased stamina, dizziness, paleness, shortness of breath, and an increased heart rate. Anemic children may grow and develop more slowly. An aplastic crisis may occur when there is a disruption in RBC production. The most common reason for an acute decrease in RBC production is an infection by parvovirus B19.
- Infections, especially lung infections, can be serious in those with sickle cell disease. According to the Centers for Disease Control and Prevention, pneumonia is a leading cause of death in children with sickle cell disease.
- Acute chest syndrome, due to vaso-occlusion, is a lung injury that can cause symptoms such as coughing, chest pain, and fever. This condition requires prompt medical attention. It can develop rapidly and become life-threatening.
- Stroke is one of the most feared complications of sickle cell anemia as it can cause permanent damage and disability. Stroke is more common in children than in adults, occurring in 10% of children with sickle cell anemia.
- Splenic sequestration is the rapid enlargement of the spleen when many sickle cells are trapped in the spleen. Occurring primarily in children, it can cause symptoms such as abdominal pain, nausea, and weakness that can progress to shock. This condition can be life-threatening and may require the removal of the spleen.
Other complications of sickle cell disease may include gallstones, bone necrosis, kidney disease, leg ulcers, disease of the retina in the eye (retinopathy), and sustained erection (priapism). Found throughout the world, sickle cell anemia is most common in those of African descent and in those from Mediterranean countries, the Middle East, India, the Caribbean, and Central or South America. According to the National Heart, Lung, and Blood Institute, about 70,000 people in the U.S. have sickle cell anemia. It affects about 1 in 500 African Americans and 1 in 36,000 Hispanic Americans. As many as two million people in the U.S., including 1 in 12 African Americans, are estimated to have sickle cell trait.