Transcript Sickle Cell Trait - Sickle Cell Disease

Sickle Cell Trait:
Know Your Status
Jacqueline Rodriguez-Louis, MPH, M.Ed.
Overview
What is Sickle Cell Trait (SCT)?
 Who Has SCT?
 What causes SCT?
 Why Do I Care about SCT?
 What is Sickle Cell Disease (SCD)?
 Sickle Cell Trait: What Do I Do Next?
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What is Sickle Cell Trait?
• Hemoglobin
– Found in the red blood cells
– Carries oxygen in the blood
• Many types of Hemoglobin
– Hemoglobin A: Adult Hemoglobin
– Hemoglobin S: Sickle Hemoglobin
• Sickle Cell Trait
– Individuals have Hemoglobin A + S
Who has Sickle Cell Trait?
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~3 million people in the US have sickle cell trait (SCT)
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1 in 12 (8%) African Americans in the US have SCT
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Also commonly seen in…
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South American (Brazil)
Central American (Honduras)
Caribbean (Haiti)
Mediterranean (Greece)
Middle Eastern (Saudia Arabia)
South Central Asian populations (India)
Malaria and Sickle Cell Trait
Mediterranean
• Malaria is an
infection of the
red blood cells
Caribbean
Central,
South
America
Africa
India
Middle
East
• Sickle cell trait
provides some
protection
against malaria
Malaria and Sickle Cell Trait
Mediterranean
• Malaria is an
infection of the
red blood cells
Caribbean
India
Middle
East
Central,
South
America
• Sickle cell trait
provides some
protection
against malaria
Africa
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How does someone get SCT?
It is inherited, it is not contagious!
 We inherit 2 genes for hemoglobin
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1 Adult
hemoglobin
1 Sickle
hemoglobin
(Hemoglobin A)
(Hemoglobin S)
Sickle Cell Trait
(Hemoglobin AS)
Diagnosis of Sickle Hemoglobin
in Infancy
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Since 2006, all US babies undergo newborn
screening for Sickle Hemoglobin
All babies screened in MA since 1990
 Identifies sickle cell disease and trait
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Diagnosis of Sickle Hemoglobin
in Pregnancy
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All pregnant women are screened through
blood tests at the start of prenatal care
If found to have any abnormal values,
additional testing is done for mother
 Fathers are screened if mother has sickle
cell trait or another abnormal hemoglobin
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Stopped targeted screening because
ethnicity no longer reliable
Treatment of Sickle Cell Trait
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NO routine treatment needed
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RARE Problems
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Rapid enlargement of spleen at high altitudes
Occasional microscopic blood in urine
Extreme exercise or dehydration – e.g., NCAA
• Kidney problems and even death
• NOTE: Extreme exercise or dehydration can cause these
same problems in the general population
Sickle Cell Disease
Facts: Sickle Cell Disease
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Most commonly inherited disease in US
2,000 newborns/year diagnosed
 1 in 400 African American births
 1 in 16,000 Hispanic births
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• Approximately 1 in 1,100 Hispanic births on
East Coast
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SCD affects approximately 100,000
individuals in the US
http://www.nhlbi.nih.gov/health/healthtopics/topics/sca/
Types of Sickle Cell Disease
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More severe forms
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Less severe forms
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Hb SS (sickle cell anemia) – 60%+
Hb SC disease – 25%
Many other forms, less common in US
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How is sickle cell disease inherited?
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Autosomal recessive inheritance
If both parents have trait:
• 1 in 4 (25%) chance to have a child
that will not have sickle cell disease
or SCT
• 2 in 4 (50%) chance to have a child
with SCT
• 1 in 4 (25%) chance to have a child
with sickle cell disease
http://www.cdc.gov/ncbddd/sicklecell/
Common Features of SCD
Anemia: Hemoglobin levels in SCD = 7-10
Normal level: 12-15
Children with SCD
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Pain episodes
Stroke
Acute Chest Syndrome
Infection
Adults with SCD
 Bone disease
 Eye disease
 Gall bladder disease
 Leg ulcers
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Sickle Cell Trait: Next Steps
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Talk to your family
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Does anyone have sickle cell
disease?
Talk to your doctor
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Does it make sense to be screened
for sickle cell trait?
• CBC, Hemoglobin electrophoresis
Thank you!
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Questions?
Survival in Sickle Cell Anemia
80
Years
70
All Americans
60
50
42 yr men
40 48 yr women
30
20
Sickle
Cell Anemia
10
0
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
CDC 2006