Dr. M.J. Bazos, MD
Patient
Handout
ANEMIA,
SICKLE CELL
About Your
Diagnosis
Sickle cell anemia is a
genetic disease in which the red blood cells contain an abnormal hemoglobin
known as hemoglobin S (Hb S). Hemoglobin is the material in red blood
cells that carries oxygen from the lungs to the rest of the body. The abnormal
hemoglobin has a tendency to aggregate, especially in parts of the body where
oxygen content is low. This aggregation causes the red blood cells to form a
sickle shape, which gives the disease its name. Sickle cell anemia is caused by
a mutation in the DNA (deoxyribonucleic acid) that codes for betaglobin, one of
the proteins that makes up hemoglobin. More than 50,000 persons in the United
States have sickle cell anemia. The disease is most common among
African-Americans, but is also seen among persons of Mediterranean, Caribbean,
South and Central American, Arabian, and East Indian ancestry. Sickle cell
anemia is a hereditary disease.
Patients
inherit the abnormal gene from
both their mother and their father; therefore their bodies can make only Hb S.
The parents of patients with sickle cell anemia may have either sickle cell
disease or sickle cell trait. Persons with sickle cell trait have one sickle
cell gene and one normal beta-globin gene. They can make both Hb S and normal
hemoglobin (Hb A). Persons with sickle cell trait are healthy but can have
children with sickle cell anemia. Sickle cell anemia is diagnosed by means of a
blood test to determine that the red blood cells form a sickle shape. The blood
test is followed by a more detailed examination of the blood to determine the
presence of Hb S, Hb A, or any other abnormal hemoglobin. A few patients with
sickle cell disease have been cured with bone marrow transplantation from a
brother or sister. However, this treatment remains highly
experimental.
Living With Your
Diagnosis
Sickle cell anemia is
characterized by acute episodes of illness, known as crises. The most
common type of crisis is a vasooclusive or painful crisis; it is believed to be
caused by blockage of blood vessels by sickled red blood cells. Patients
experience severe pain, usually in the bones, and may have a fever. Symptoms
usually last several days but may persist for more than a week. Sickle cell
anemia can affect every organ of the body, leading to complications such as
kidney disease, eye disease, chronic hip or shoulder pain, heart disease, and
leg ulcers. Sickling of red blood cells in the blood vessels of the brain may
lead to strokes. Men with sickle cell anemia may have priapism, a persistent,
unwanted erection. Sickling in the spleen causes the organ to become inactive,
making patients with sickle cell anemia prone to infections. Some of the more
common infections are osteomyelitis (bone infection) and pneumonia. Patients
with sickle cell anemia may have a
serious
lung disorder known as acute
chest syndrome. This syndrome is believed to be caused by a combination of
sickling in the blood vessels of the lung and ribs and pneumonia. Patients with
sickle cell anemia also may experience a type of crisis known as aplastic
crisis, in which the bone marrow
temporarily
stops making red blood cells.
This type of crisis is usually associated with an infection (especially with the
organism parvovirus B19) and can lead to severe anemia. It is safe for patients
with sickle cell anemia to travel in pressurized aircraft. However, travel in
nonpressurized aircraft at high altitudes may trigger a
crisis.
Treatment
Treatment
of sickle cell crisis involves controlling the pain. Mild crises can be managed
with oral medications, which may or may not be narcotics. More severe pain
crises may necessitate use of narcotics administered by means of intramuscular
or intravenous injection. Fluids are given to prevent dehydration. Severe
complications of sickle cell disease, such as stroke or acute chest syndrome,
may be managed by means of exchange transfusion, which involves removing the
patient’s abnormal red blood cells and replacing them with normal red
blood cells. Hydroxyurea is a chemotherapeutic drug that appears to decrease the
frequency of pain crises among patients with sickle cell anemia. Some patients
with severe symptoms of sickle cell
anemia
may be treated with this drug.
Narcotic pain medications can cause drowsiness and constipation. Aspirin and
nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can cause
stomach pain and platelet abnormalities (platelets are blood cells that help
form clots). Hydroxyurea can cause a decrease in all blood cell counts: red
blood cells, white blood cells, and platelets. A low red blood cell count
(anemia) can cause fatigue and shortness of breath. A low white blood cell count
(neutropenia) can increase susceptibility to infection. A low platelet count
(thrombocytopenia) can lead to easy bruising or bleeding. Use of narcotics can
lead to physical dependence and symptoms of withdrawal if the drug is stopped
too quickly. However, true addiction (a psychological need for the drug) is
rare. Overuse of aspirin or NSAIDs can cause stomach ulcers and kidney disease.
Overuse of acetaminophen (eg, Tylenol) may produce liver damage. Hydroxyurea can
cause fetal abnormalities; therefore patients should not become pregnant or
father a child while taking it. Children with sickle cell anemia generally
receive prophylactic penicillin to prevent bacterial infection. Many sickle cell
crises may be managed at home with oral pain medications, hydration, and
rest.
The
DOs
• Take a daily folate
supplement.
• Drink plenty of fluids
to avoid dehydration, especially if you begin to have a painful
crisis.
• Eat a healthy diet that
contains green, leafy vegetables, which are high in
folate.
• Participate in mild to
moderate exercise as tolerated but be careful to rest if you feel tired and
drink fluids after exertion.
• Dress
warmly and avoid exposure to cold if possible; cold temperatures may trigger a
crisis.
• Inform the surgeon or
dentist that you have sickle cell anemia if you are undergoing elective surgical
or dental procedures.
• Consider
genetic counseling to determine your risk for having an affected
child.
• Undergo prenatal care with
both your obstetrician and your primary care physician. Although you may have a
more complicated pregnancy than women without sickle cell disease, your
likelihood of delivering a healthy baby is excellent.
The
DON’Ts
• Do not overuse pain
medications.• Avoid excessive
consumption of alcohol.• Avoid
overexertion.• Avoid swimming in
cold water, which may trigger a
crisis.When to Call Your
Doctor• If you have a fever,
shortness of breath, severe abdominal pain, priapism, neurologic symptoms (such
as weakness on one side of your body or difficulty speaking), or a painful
crisis that does not respond to management at
home.Websites:MedMark
Hematology: http://medmark.bit.co.kr/hematol.htmlhttp://www.uncfsu.edu/osc/Joint
Center for Sickle Cell and Thalassemic Disorders:http://cancer.mgh.harvard.edu/medOnc/sickle.htm