American Medical Association Family Medical Guide - American Medical Association [366]
In the United States, sickle cell disease and sickle cell trait occur most frequently among African Americans and Hispanics of Caribbean ancestry. About 1 in every 10 African Americans carries the gene for sickle cell disease. Each child of a man and woman who both have the sickle cell trait has a 25 percent chance of inheriting the sickle cell gene from each parent and having the disease.
Symptoms
A person who has sickle cell disease has symptoms of anemia, such as weakness, fatigue, shortness of breath, and palpitations (heartbeats that you’re aware of ). In addition to these symptoms, he or she may have headaches and jaundice (yellowing of the skin and the whites of the eyes). Occasional sickle cell crises occur when the abnormal cells block small blood vessels and cause tissue in the bones, joints, or abdomen to die; a person will have severe pain in the long bones and in the abdomen, sometimes along with nausea and vomiting. The person also may experience fever and shortness of breath.
The frequency of sickle cell crises varies from person to person. Crises are more likely to occur when a person has an infection, has been injured, or has had prolonged exposure to cold weather. Because sickle cell crises can occur during anesthesia and surgery, precautions are taken before surgery to prevent them.
Lack of an adequate blood supply to organs may cause areas of tissue in the organs to die. Poor circulation also can cause sores to develop on the legs and ankles. Damage to the nervous system can lead to stroke (see page 669). Older people with sickle cell disease may develop impaired lung and kidney function. Younger men may develop priapism (see page 840), a condition that causes persistent, often painful, erections.
Diagnosis
For a person who has symptoms of sickle cell disease, a doctor will take a detailed family health history, perform an examination, and order a blood test to check for abnormal hemoglobin and to determine if the person has sickle cell disease or sickle cell trait. Symptoms such as anemia, abdominal and bone pain, and nausea usually indicate sickle cell disease. Sickle cell disease can be diagnosed in a fetus during pregnancy by CVS (chorionic villus sampling; see page 511) between the 10th and 12th weeks of pregnancy or by amniocentesis (see page 510) later in pregnancy. In most states, all newborns are tested for sickle cell disease so that treatment can begin early for a child who is found to have the disease.
Treatment
Because sickle cell disease cannot be cured, treatment focuses on relieving symptoms and preventing sickle cell crises. Sickle cell crises are often treated with analgesics to relieve pain, supplemental oxygen to increase the supply of oxygen to tissues, and both oral and intravenous fluids to help prevent dehydration. For adults with sickle cell disease, a doctor may prescribe a cancer drug called hydroxyurea to increase the amount of hemoglobin F (fetal hemoglobin, which protects against sickling) in the blood and decrease the number of sickle-shaped red blood cells. The doctor may prescribe folic acid supplements to increase the body’s production of red blood cells to help replace dead and damaged cells. Other treatment options include blood transfusions (see below), antibiotics, and sometimes a stem cell or bone marrow transplant (see page 624), which can have significant risks.
The effects of sickle cell disease
Abnormal sickle-shaped blood cells can clog tiny blood vessels and prevent blood (and oxygen) from reaching tissues throughout the body. For this reason, sickle cell disease can affect many different organs and functions.
A person who has sickle cell disease needs to do everything possible to maintain good health. He or she should see the doctor regularly for checkups and seek prompt medical treatment for even minor illnesses, such as colds and other viral infections, or minor injuries. As a precaution, a doctor will immunize