Blood tests can determine whether an individual has sickle cell trait or sickle cell disease.

Screening Tests for Newborns

In the United States, hospitals routinely screen newborn babies for sickle cell disease. To perform the test, a blood sample is taken from the baby's heel using a simple needle prick. Early detection of sickle cell disease can help reduce the risk for life-threatening infections and increase the odds for survival. Babies who are diagnosed with sickle cell disease are given daily antibiotics to help prevent infections.

Prenatal diagnosis is also possible through amniocentesis. The amniotic fluid is tested for the presence of the sickle cell gene.

Diagnostic Tests for Stroke

Unfortunately, no tests can definitely determine which children are at highest risk for a stroke and, therefore, would be candidates for ongoing blood transfusions. The following are diagnostic tools currently used or under investigation:

• Transcranial Doppler (TCD) ultrasonography measures the speed of blood flow in the brain. It can be used for identifying children at risk for stroke. However, high-risk children are still vulnerable to stroke even if the TCD screening diagnosed normal blood flow velocities.
• The use of follow-up magnetic resonance imaging (MRI) to detect small blockages in blood vessels may help confirm high risk in patients identified by TCD ultrasound.
• Some patients may need to undergo angiography, an invasive diagnostic technique useful for detecting aneurysms.
• Researchers are also beginning to uncover possible genetic markers that may eventually be used to help identify sickle cell patients at higher risk for stroke.

New and aggressive treatments for sickle cell disease are prolonging life and improving its quality. As recently as 1973, the average lifespan for people with sickle cell disease was only 14 years. Currently, life expectancy for these patients can reach 50 years and over. Women with sickle cell live longer than their male counterparts.

The damage of sickle cell disease occurs because the logjam that sickle cells cause in the capillaries slows the flow of blood and reduces the supply of oxygen to various tissues. Not only does pain occur when body tissues are damaged by lack of oxygen, but serious and even life-threatening complications can result from severe or prolonged oxygen deprivation. Sickle cell disease is referred to in some African languages as "a state of suffering," but the disease has a wide spectrum of effects, which vary from patient to patient. In some people, the disease may trigger frequent and very painful sickle cell crises that require hospitalization. In others, it may cause less frequent and milder attacks.

Children with sickle cell disease are very susceptible to infections, usually because their damaged spleens are unable to protect the body from bacteria. Signs of impaired lung function may occur even in very early years. As children with sickle cell disease live longer, older patients are now facing medical problems related to the long-term adverse effects of the disease process. The most serious dangers are acute chest syndrome, long-term damage to major organs, stroke, and complications during pregnancy such as high blood pressure in the mother and low birth weight in the infant.