Sickle cell disease

What is sickle cell disease?

Sickle cell disease is an inherited blood disease that can cause bouts of pain, damage to vital organs, and for some, death.  It affects males and females equally.  It affects a protein inside the red blood cells called hemoglobin.  It occurs when a person inherits two sickle cell genes or a combination of one sickle cell gene plus any one of several other abnormal hemoglobin genes that affect the red blood cells.

Hemoglobin carries oxygen from the lungs and takes it to every part of the body.  A change in the oxygen-carrying hemoglobin inside the red blood cells causes the symptoms of sickle cell disease.  Red blood cells are normally round and flexible.  In people with sickle cell disease, when oxygen is released, the cells become distorted, forming a sticky and rigid banana- or sickle-shaped cell that can clog the vessels.

Sickle cells tend to become trapped and destroyed in the liver and spleen.  This results in a shortage of red blood cells called anemia which, when severe, can cause the patient to be pale, short of breath and easily tired.  Certain conditions, such as infections, may worsen a patient’s anemia by speeding up destruction of red blood cells or reducing red blood cell production.

Two of the most common forms of sickle cell disease are sickle cell anemia (SS disease) and sickle “C” disease.  Sickle beta thalassemia is a less common form.  The effects of sickle cell disease vary greatly from one person to the next.  Some affected people rarely see their doctors for sickle cell-related complaints; others may be hospitalized frequently.

What special problems people with sickle cell disease have?

Sickle cells disease is a serious health problem.  These problems can include: pneumonia, organ damage, painful erections in men, swelling of hands and feet, complications in pregnancy, chest pains and trouble breathing, blood in urine, fever, stroke, leg ulcers, infections, jaundice, gallstones, anemia, and pain.

Infants and young children with sickle cell disease are especially vulnerable to severe bacterial infections, such as those that cause meningitis and pneumonia.

Infections are the leading cause of death in children with children with sickle cell disease.  However, early diagnosis and treatment dramatically reduce the risk of infections and the deaths that result from them.

In 1987, a National Institutes of Health panel recommended that all babies be screened at birth for sickle cell disease.  To date, some 30 states are testing newborns for sickle cell disease.  All newborn babies in Texas are tested for sickle cell disease, despite race or ethnicity.

Do we all have the same chance of inheriting sickle cell disease?

No. In theUnited States, most cases of sickle cell disease occur among blacks and Hispanics of Caribbean ancestry.  About one in every 400-600 blacks inherits sickle cell disease.  It also affects people of Arabian, Greek, Maltese, Italian, Sardinian, Turkish and southern Asian ancestry. It is not contagious.

Is sickle cell “trait” the same thing as sickle cell disease?

No.  Carriers of a single sickle cell gene are said to have sickle cell trait.  One in 10 blacks in this country has sickle cell trait.  They are as healthy as non-carriers, rarely having any health problems related to the trait.  They cannot later develop sickle cell disease.  However, when two carriers have a child, their child may inherit two sickle cell genes and have the disease.

What are the chances that parents with sickle cell trait will pass it on to their children?

There is a 50% chance that a child born to a couple who both carry a sickle cell gene will have the trait like the parents.  There is a 25% chance that the child will have sickle cell disease.  There is also a 25% chance that the child will have neither the trait nor the disease.  Each successive pregnancy has the same set of chances.  If only one parent has the trait, there is no chance that their children will have sickle cell disease.

Can a woman with sickle cell have children?

Yes.  Women with sickle cell disease can have normal pregnancies.  However, affected women are at an increased risk of complications that can affect their health and that of their babies.  During pregnancy, the disease may become more severe and painful crises may occur more frequently.  A pregnant woman with sickle cell disease is at an increased risk of miscarriage and of having a low-birthweight baby.

With early prenatal care and careful monitoring throughout pregnancy, the outlook for a healthy pregnancy has improved.