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Sickle Cell Disease
and
Women’s Health
Common Types of Sickle Cell
• Sickle Cell Anemia (SS),
• Sickle-Hemoglobin C Disease
(SC)
• Sickle Beta-Plus Thalassemia
and
• Sickle Beta-Zero Thalassemia.
About Sickle Cell
• 72,000 Americans are affected with Sickle Cell Anemia
• SCA is an autosomal recessive disease caused by a point
mutation in the hemoglobin beta gene (HBB) found on
chromosome 11p15.4
• Sickle cell disease is an inherited blood disorder that affects red
blood cells. People with sickle cell disease have red blood cells
that contain mostly hemoglobin S, an abnormal type of
hemoglobin. Sometimes these red blood cells become sickleshaped (crescent shaped) and have difficulty passing through
small blood vessels.
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?call=bv.View..ShowSection&rid=gnd.section.98
Who Gets SCDs?
• 1 in 500 African Americans are
affected with Sickle Cell Anemia
• The different kinds of SCD and the
different traits are found mainly in
people whose families come from:
• Africa, (as many 25% of infants are born with
the disease in some areas)
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the Caribbean,
the Eastern Mediterranean,
Middle East and
Asia.
Who Gets SCDs?
• Carriers of the Sickle Cell trait vary by
population.
• Sickle trait is protective against malaria.
• Frequency of trait carriers vary by population group
as follows:
• 1/14 African American
• 1/183 Hispanic
• 1/625 Caucasian
• 1/1336 Asian
http://www.labcorp.com/genetics/genetic_disorders/sickle_cell_disease.html
anthro.palomar.edu/ synthetic/synth_7.htm
Risks in Pregnancy with Sickle Cell
Health complications that can affect the
mother and her babies.
Preterm labor
Sickle Crisis
Pulmonary infarction
Pyelonephritis
Thrombophlebitis
Spontaneous
Abortions
Low-birthweight baby
Toxemia
Acute chest syndrome
Pneumonia
Fetal death
Antepartum hemorrhage
Sickle Cell and Pregnancy
• Pregnant women may experience
more severe and pain episodes more
frequently
• With early prenatal care and careful
monitoring throughout pregnancy,
women with sickle cell disease can
have a healthy pregnancy.
• If the baby’s father has sickle cell trait,
the baby has a 50 percent chance of
having the disease. [If he does not, the
baby will have only the trait].
Sickle Cell Genetics
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Sickle cell trait is not synonymous to sickle cell disease.
The allele is incompletely recessive.
People with sickle cell trait are generally healthy.
Conditions are inherited from parents the same way as blood
type, hair color and other physical traits.
Causes of Complications
• People with sickle cell make a different form of hemoglobin
A called hemoglobin S (S stands for sickle)
• This is due to a mutation in the ß-globin chain of
hemoglobin, replacing glutamic acid with less polar
valine at the sixth position of the ß chain .
• The association of two wild type a-globin subunits with
two mutant ß-globin subunits forms hemoglobin S, which
polymerizes under low oxygen conditions causing
distortion of red blood cells and a tendency for them to
lose their elasticity.
http://www.sicklecelldisease.org/about_scd/index.phtml
www.worldofmolecules.com/ disease/hemoglobin_S.htm
Sickling
• Red blood cells containing mostly hemoglobin S live
only about 16 days versus 120 days of normally
shaped cells. They also carry less oxygen, become
stiff, distorted in shape and have difficulty passing
through the body’s small blood vessels.
• When sickle-shaped cells block small blood vessels,
less well oxygenated blood can reach parts of the
body. Tissue that does not receive a normal blood
flow eventually becomes damaged.
Symptoms of SCA
• Symptoms appearing at six months of age may include
enlargement of the abdomen and heart and painful swelling
of the hands and feet. Growth is often delayed.
• In adolescence, sexual maturation may be delayed.
• The disturbances in blood flow associated with the disease
also dispose affected people to infections and leg ulcers.
• These symptoms are due to the altered hemoglobin, which
changes shape when the amount of oxygen in the blood is
reduced for any reason. The red blood cell in which the
hemoglobin is contained also changes its shape, from round
to crescent (sickle shaped).
http://www.fortunecity.com/greenfield/rattler/46/Anaemia.html
Medical Complications
• Sickle cells are destroyed rapidly in the body of people with
the disease causing anemia, jaundice and the formation of
gallstones.
• The sickle cells also block the flow of blood through vessels
resulting in lung tissue damage (acute chest syndrome), pain
episodes (arms, legs, chest and abdomen), stroke and
priapism (painful prolonged erection).
• It also causes damage to most organs including the spleen,
kidneys and liver. Damage to the spleen makes sickle cell
disease patients, especially young children, easily
overwhelmed by certain bacterial infections.
Acute Chest
Syndrome
http://europa.redjupiter.com/images/pediatriceducation/110104SickleCellAcuteChestC.jpg
Crisis Types
1. Vaso-Occlusive – common (Painful)
2. Aplastic – usually associated with infections
(Parvovirus B19)
3. Sequestration – particularly in infants and
children; in those with SC and S-beta Thal
(cause of death in 10-15% under 10 years of
age)
4. Hemolytic – rare
Vaso-Occlusive Crisis
• Results from infarction due to sickled, poorly
oxygenated blood
• Symptoms are diffuse and bilateral pain
• Organ damage includes:
– Spleen to the point of becoming nonfunctional by age 2-4
– CNS
• Cerebral infarction in children
• Hemorrhage in adults
– Bones (avascular necrosis especially femur)
– Also kidney, eyes, liver
PHYSICIANS NEED TO TREAT PAIN APPROPRIATELY AND
AGGRESSIVELY WITH FLUIDS AND PAIN MEDICATIONS!
pedsccm.wustl.edu/.../ head/ct/cerinfarc2.html
Precipitants of Vaso-Occlusive Crisis
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Low oxygen tension (high altitudes)
Dehydration
Acidosis
Extreme physical exercise
Physical or psychological stress
Alcohol
Pregnancy
Cold weather
Pre-existing medical conditions (such as DM, HSV,
sarcoidosis)
Leg Ulcers
www.meddean.luc.edu/.../ pulmonar/pd/step52b.htm
Child being treated for leg ulcer
•www.studentbmj.com/ issues/03/12/education/450.php
Bleeding and Clotting
Complications
• Recurrent fetal loss
• Symptoms of a bleeding disorder might include
– unusually hard-to-control bleeding after minor injury,
childbirth, or surgery;
– excessive bleeding from the gums after flossing, brushing,
or having a tooth removed;
– frequent or long nosebleeds;
– and easy bruising
http://www.cdc.gov/ncbddd/hbd/women.htm
Stroke and Sickle Cell
• A stroke is a sudden and severe complication of
sickle cell anemia.
• Strokes affect from 6 to 8% of patients with sickle
cell anemia, especially between 2 and 10 years of
age.
• The sickled cells in a child with sickle cell anemia
result in cerebral infarction.
http://www.dshs.state.tx.us/newborn/sickle.shtm
Testing for SCDs
• A hemoglobin electrophoresis can tell whether
a patient has a sickle cell disorder or is a
healthy carrier, e.g. for sickle cell trait.
• Routine screening should take place for
people in the groups listed during pregnancy
and before anesthesia, either at hospital or
dental clinics.
erasmeinfo.ulb.ac.be/.../ English/sickle_diag.htm
Although there is no cure for sickle cell
disorders, physicians and other
professionals can help to reduce the
frequency and severity of crises and their
complications by prompt recognition and
treatment.
Treatment Tips
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Aim for the patient to live as normal a life as possible but be prepared
to take immediate action if he or she becomes ill. Treat infection
early.
Maintain general health and nutrition. Make sure that the patient
keeps warm and dry.
Avoid situations likely to precipitate crisis e.g. dehydration, acidosis,
general anesthesia, and sports such as skydiving and scuba diving.
Arrange regular blood tests. These are needed for reference in a crisis
and to monitor kidney and liver function .
Consider folic acid supplements.
All patients with sickle cell disorders should be offered prophylactic
penicillin.
Treatment Tips
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Pneumococcal vaccination should be offered although it does not
protect against all strains of pneumococci.
Ensure adequate malaria prophylaxis as sickle cell disease offers no
protection - but see 9 below.
Beware of coexistent Glucose-6-phosphate dehydrogenase (G6PD)
deficiency. There is a high incidence in the population groups prone
to sickle cell disorders. Acute hemolytic crisis may be provoked in
people with sickle cell disease by eating broad beans (favia) or by
the administration of certain drugs including some anti-malarials.
Offer genetic counseling.
Give the patient a hemoglobinopathy card or a letter giving details
of his or her condition.
Cognitive Behavioral Therapy can be effective for managing sickle
cell disease and pain
Treatment
• Health maintenance starts with early diagnosis, preferably in
the newborn period and includes penicillin prophylaxis,
vaccination against pneumococcus bacteria and folic acid
supplementation.
• Blood transfusions help by reducing recurrent pain crises, risk
of stroke and other complications.
• It is important to remove excess iron from the body, because
it can gather in the heart, liver, and other organs and may
lead to organ damage.
• Treatments are available to eliminate iron overload.
Promising Treatment
Developments
• In search for a substance that can prevent red blood cells from
sickling without causing harm to other parts of the body,
Hydroxyurea was found to reduce the frequency of severe
pain, acute chest syndrome and the need for blood
transfusions in adult patients with sickle cell disease.
• Droxia, the prescription form of hydroxyurea, was approved
by the FDA in 1998 and is now available for adult patients
with sickle cell anemia. Studies will now be conducted to
determine the proper dosage for children.
• Other treatment options in clinical development include new,
more convenient options than current therapies to eliminate
iron overload caused by repeated blood transfusions.
• Transplantation can convert patients into carriers.
Local Resources
Pennsylvania SCDAA –
Philadelphia / Delaware Valley
4601 Market St.
Philadelphia, PA 19139
Stanley A. Simpkins, Executive
Director
(215) 471-8686 – Office
(215) 471-7441 – Fax
E-Mail:
[email protected]
Website:
www.sicklecelldisorder.net
HRS: 9:00am – 5:00pm
The South Central Sickle Cell
Council
3211 North Front Street, Suite 103
Harrisburg, PA 17110
Patricia A. Prim, Executive
Director
(717) 234-3358 – Office
(717) 234-1907 – Fax
E-Mail: [email protected]
HRS: 9:00am -5:00pm