Sickle Cell Anemia

Sickle Cell Overview

Sickle Cell Anemia is an inherited disorder in which red blood cells (RBC's) are abnormally shaped. This abnormality can result in serious infections, chronic anemia, and damage to body organs. Each person can have different forms of complications from the disorder. Some children remain relatively healthy, while others are frequently hospitalized. Due to recent advancements in early diagnosis and treatment, most children born with this disorder can grow up to live relatively normal lives.

Forms of Sickle Cell Anemia

Forms of sickle cell anemia are determined by the genes inherited from the child's parents. Children affected with the disease have inherited a sickle cell gene from each parent. A child can also inherit a sickle cell gene from one parent and a different kind of abnormal gene from the other and end up with a different form of sickle cell disease such as hemoglobin, SC disease, or hemoglobin s-thalassemia. Someone who inherits only one sickle cell gene and a normal gene from the other parent will have the sickle cell trait, but not the disease. A blood test can determine whether you have the disease or carry the cell trait. People who carry the trait don't have sickle cell disease or exhibit any signs of the disorder but they can still pass the disease on to their future children. When both parents carry the sickle cell trait there is a 25% that the child will have the sickle cell disease. When one parent carries the trait and the other actually has the disease, the odds increase to 50% that the child will inherit the disease.

Children Affected

In the United States Sickle Cell Anemia affects mostly African Americans. Some forms of sickle cell anemia may occur in children who come from different ethnic backgrounds (Greek, Turkish or Middle Eastern ancestry); however this is often a very rare case.

Causes of Sickle Cell Anemia

Children with sickle cell disease have two inherited, defective hemoglobin genes. The hemoglobin gene can take on an abnormal shape, distorting the shape of the red blood cell. The cells change from a normal round, doughnut shape to the elongated shape of a sickle, or letter "C". Sickle cells are usually stiff and pointed, unlike normal RBC's which move easily through small blood vessels. Their shape means that they have a tendency to get stuck in narrow blood vessels and block the flow of blood. This can cause severe pain in the child and lead to organ damage due to the cells not getting enough oxygen. Sickle cells have a shorter-than-normal life span, which leads to a low red blood cell count. Normal red blood cells can live up to approximately 120 days, whereas a sickle cell lives for only 10 to 20 days.

Diagnosis

Sickle cell disease is usually diagnosed at birth with a blood test. This can be performed along with other routine newborn screening tests. If a child tests positive on the test, a second screening is conducted in order to confirm the diagnosis. Children with sickle cell disease are at an increased risk for infection and other health problems, early diagnosis and treatment is important! Currently more than 40 states are required to perform newborn screening tests in their hospitals right after birth.

Symptoms

Symptoms of sickle cell disease can vary and range from mild to severe, with symptoms varying a child who has inherited a sickle cell gene from one parent and a different abnormal hemoglobin gene from the other.  Most children with sickle cell disease have anemia and may develop one or more of the following conditions and symptoms as part of the disorder:

Acute chest syndrome Inflammation or trapped red blood cells in the lungs.

Aplastic crisis Bone marrow temporarily slows its production of RBC's due to infection.

Hand-foot syndrome (dactylitis) Painful swelling of the hands and feet, followed by fever.

Infection Children with sickle cell anemia are at an increased risk for certain bacterial infections. High fevers are usually a common sign and require immediate attention by a doctor.

Painful crises Can occur in any part of the body and may be caused by cold or dehydration. Pain may last a few hours or up to 2+ weeks. The pain may be so severe that hospitalization would be required. 

Splendic sequestration crises The spleen becomes enlarged by trapping the abnormal RBC's. This leads to fewer cells in the general circulation. Early signs include paleness, weakness, enlarged spleen, and pain in the abdomen.

Stroke Poor blood blow can occur in the brain when sickle cells block small blood vessels. This may lead to stroke. Signs include headaches, seizures, weakness of the arms and legs, speech problems, a facial droop and loss of consciousness.

Other possible complications can include: leg ulcers, bone and joint damage, gallstones, kidney damage, painful prolonged erections in males, eye damage and delayed growth. 

Treatment

Besides a bone marrow transplant, there is no known cure for sickle cell disease. Transplants can become a complicated procedure and are not advised for everyone. To qualify a child would need bone marrow from a "matched" donor with a low risk of being rejected. There are significant risks towards the procedure, along with a high chance of rejection of the transplanted marrow.

Even without a cure, children with sickle cell disease can lead very normal lives. Certain types of medication can be taken to help manage the pain, and immunizations (penicillin) can prevent infections. Infants and young children usually require two daily doses of penicillin, as prescribed by their doctors until they are at least five years old. They should also be fully immunized with all regular childhood vaccinations. Many doctors will also prescribe daily vitamin supplements, such as Folic acid which can help a child produce new RBC's.  Children who develop serious complications such as anemia or stroke may receive regular transfusions of red blood cells to prevent or treat these complications.

The drug hydroxyurea has yet to be officially approved for use in children. Although it has been approved to be taken by adults, some specialists may approve of its use on children in very special circumstances. Hydroxyurea increases the amount of fetal hemoglobin in blood cells, which interferes with the sickling process and makes red blood cells less sticky. This helps decrease the number and intensity of painful episodes and other complications. The drug has been proven to reduce pain in adults and children. Research is still being conducted to determine the drugs long term effects and safety so that all children one day will be able to receive treatment from Hydroxyurea. 

Caring for Children with Sickle Cell Disease

In addition to the primary care given by a doctor parents should also make sure that their child receives regular care from a hematologist (blood specialist). Children should also drink plenty of liquid and get plenty of rest. It is also advised that children avoid extreme temperatures. The average life span for someone with sickle cell disease can live up until at least 40 years old, and many even longer. The most critical time for someone with sickle cell is during infancy, which is why early diagnosis and treatment is very important. 

Emergency medical care should be sought immediately if any of the following occur:

Fever of 101F or higher

Swollen hands or feet

Sudden paleness of the skin or nail beds

Yellow color of skin or eyes

Swelling in the abdomen

Trouble hearing or seeing

Weakness on one side of the body or a sudden change in speech

Headache

Joint, stomach, chest, muscle pain or limping

Can Sickle Cell Disease be Cured?

No cure has yet been discovered. With professional treatment and good care most people with the disease can live a very normal life. Bone marrow transplants can cure the disease in a small number of people.

Facts about Sickle Cell Disease

Sickle Cell Disease is the most common hereditary hematologic disorder in the world

Children with Sickle Cell Disease start to have signs of the disease during their first year, usually at around 5 months

About 8% of the African-American population carries the sickle cell trait

In the US there are around 50,000 African-Americans and Hispanics affected with sickle cell disorders

Contact a CCBF Doctor

If you have any questions or would like to schedule an appointment, please call 212-746-3400 to schedule a visit with Dr. Giardina.

 

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