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Health Professionals Guide to Newborn Screening
Hemoglobinopathies
Hemoglobin Diseases
A group of autosomal recessive disorders characterized by synthesis of abnormal hemoglobin molecules (e.g. S, E, C) or decreased synthesis of a beta globin chain. Those hemoglobinopathies characterized by synthesis of an abnormal molecule are detectable at birth. Affected individuals with sickle cell disease may have early overwhelming sepsis and require prompt evaluation at a comprehensive care facility.
| Prevalence (WI): |
1:400 (Sickle Cell Disease in African Americans)
1:2,500 (General Population) |
| Analytes Measured: |
Hemoglobin Fractions
Fetal (F), Adult (A), Sickle (S)
C-Hemoglobin (C), E-Hemoglobin (E) |
| Patterns Reported |
FA = Normal
FS = Hemoglobin SS disease
FC = Hemoglobin C disease
FSC = Sickle Hemoglobin-C disease
FSA = Sickle Beta Thalassemia
FE = Homozygous E disease |
| Feeding Effect: |
None |
| Timing Effect: |
None
NOTE: Specimen collection after a transfusion invalidates hemoglobin test results for a minimum of 60 days post transfusion. It is recommended that a specimen be collected prior to a transfusion, if at all possible. If a baby has been transfused or a transfusion is imminent, see When to Collect a Specimen. |
| Confirmation: |
Whole blood specimen at one month of age. The WSLH will provide a blood collection kit and no-cost testing. |
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Treatment: |
Prophylactic penicillin until age five. |
Common Hemoglobin Traits
| Prevalence (WI): |
1:10 (Sickle Cell Trait in African Americans) |
| Analytes Measured: |
Hemoglobin Fractions
Fetal (F), Adult (A), Sickle (S)
C-Hemoglobin (C), E-Hemoglobin (E)
D-Hemoglobin (D), BART Hemoglobin |
| Patterns Reported |
FA = Normal
FAS = Sickle cell trait
FAC = Hemoglobin C trait
FAD = Hemoglobin D trait
FAE = Hemoglobin E trait
FA + BART |
| Feeding Effect: |
None |
| Timing Effect: |
None (unless transfused)
NOTE: Specimen collection after a transfusion invalidates hemoglobin test results for a minimum of 60 days post transfusion. It is recommended that a specimen be collected prior to a transfusion, if at all possible. If a baby has been transfused or a transfusion is imminent, see When to Collect a Specimen. |
| Confirmation: |
Should this infant show signs of microcytic anemia or have pain of unknown etiology, check for beta (+) thalassemia by hemoglobin electrophoresis through the newborn screening laboratory. |
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Treatment: |
None |
COMMENT: Persons with hemoglobin traits are by definition carriers of an abnormal hemoglobin gene. While this fact has little clinical significance to the individual, genetic counseling is important (especially sickle cell trait (FAS)) because both parents may also be carriers creating a significant risk for a future baby to have a hemoglobin disease (i.e. sickle cell disease).
Any concern for the rare symptomatic variant (non-sickle) can be monitored through clinical observations (anemia, jaundice, cyanosis) combined with a hemoglobin electrophoresis, CBC, and reticulocyte count. By one year of age, some children may show a mild microcytic anemia. The presence of BART hemoglobin is an exception as it may be clinically significant, especially in Southeast Asians. Specific hematologic consultation is recommended for babies who show BART hemoglobin at newborn screening. Recommended follow-up at one year of age is CBC, reticulocyte count, and hemoglobin quantitation.
Information on treatment centers is also available on this site.
For information about other screened disorders, click on the next page button, or follow one of these links:
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