What is sickle cell disease?
Sickle cell disease is an inherited (passed from parent to
child) disorder that affects the body’s red blood cells. In this disease,
defective hemoglobin (a substance that carries oxygen in the blood) causes the
red blood cells to change shape (into a sickle) when oxygen is released to tissues.
Normal red blood cells are round and are able to move through
small blood vessels in the body to deliver oxygen. In sickle cell disease, a
chemical change in hemoglobin causes the substance to form long rods in the red
blood cell as the hemoglobin releases oxygen. These rigid rods change the shape
of the red blood cell into a sickle shape.
The disease gets its name because the faulty blood cells are
shaped like sickles used to cut wheat. When the deformed cells go through blood
vessels, they become stiff, distorted, clog the blood flow, and can break apart.
Individuals with sickle cell disease have hemoglobin "S,"
whereas others without this disease have hemoglobin "A".
Sickle cell disease is found most often in African-Americans and
Africans. However, other ethnic groups also can have sickle cell disease. In
many states, the law requires newborn babies to be tested for sickle cell
disease, regardless of ethnic background.
What causes sickle cell disease?
A chemical change in hemoglobin causes the substance to form
long rods in the red blood cell as the hemoglobin releases oxygen. These rigid
rods change the shape of the red blood cell into a sickle shape.
Sickle cell disease is not contagious. Children are born with
sickle cell hemoglobin, which they inherit from their parents. Individuals might
be carriers who have the sickle cell trait or might actually have sickle cell
disease. People who inherit only one sickle cell gene are carriers, but people
who inherit two sickle cell genes have sickle cell disease.
What are the symptoms of sickle cell disease?
Symptoms of sickle cell disease include:
- Swelling and inflammation of the joints
- Blood blockage in the spleen or liver
What are the medical problems of sickle cell disease?
Medical problems associated with sickle cell disease include:
- Respiratory illness known as acute chest syndrome
- Pain episodes
- Priapism (a persistent, usually painful, erection that lasts for more
than four hours)
Sickle cell disease can also cause damage to bones and to many
organs, including the heart, lungs, kidneys, and spleen.
How is sickle cell disease diagnosed?
Sickle cell disease is diagnosed by examining a sample of
blood under a microscope. The test used is hemoglobin electrophoresis, which
determines the type of hemoglobin one has, and if he or she is a carrier or has
the disease. When the abnormal sickle-shaped cells in the blood are identified,
a diagnosis is made.
How is sickle cell disease treated?
Currently, there is no cure for sickle cell disease.
Treatment of sickle cell disease depends upon the symptoms a person is
experiencing. Treatment includes early diagnosis, health promotion, and symptom
prevention. Some medicines that can be used to treat sickle cell disease-related pain include:
- Pain medications, including opioids and anti-inflammatory medicines
- Hydroyurea (e.g., Hydrea and Droxia)
- Iron overload therapy
- Tricyclic antidepressants such as amitriptyline
- Anticonvulsants such as Gabapentin
What is the outlook for people with sickle cell disease?
People who have sickle cell disease have a reduced life
expectancy. Some people with the disease can remain without symptoms for years,
while others do not survive beyond infancy or early childhood. New treatments
for sickle cell disease are improving life expectancy and quality of life.
People with sickle cell disease can survive beyond their 50s with optimal
management of the disease.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 10/7/2009...#12100