NEWBORN SCREENING

[FSA]

Hemoglobin S/Beta+- Thalassemia (HbSβ+ Disease)

 

Differential Diagnosis: Hemoglobin FSA pattern on newborn screen is highly suggestive of sickle beta plus thalassemia. The hemoglobins are listed in order (F>S>A) of the amount of hemoglobin present. This result is different from FAS which is consistent with sickle carrier (trait) 

Condition Description: A red blood cell disorder characterized by presence of fetal hemoglobin (F) and hemoglobin S in the absence of hemoglobin A. The hemoglobins are listed in order of the amount of hemoglobin present (F>S). This result is different from FAS which is consistent with sickle carrier 

You Should Take the Following Actions:

  • Contact family to inform them of the newborn screening result
  • Perform a physical examination of the infant and assess for splenomegaly
  • Obtain blood sample for confirmatory testing and a complete blood count with reticulocyte count
  • Initiate penicillin (Pen VK 125mg po bid) prophylaxis
  • Educate parents/caregivers regarding risks of sepsis, the need for urgent evaluation if fever of ≥101°F or signs and symptoms of splenic sequestration
  • Contact a specialist in hemoglobinopathies for consultation on diagnostic evaluation and management
  • Report findings to state newborn screening program (Carleigh Soule at 307-777-6297) 

Confirmation of Diagnosis: Hemoglobin separation by electrophoresis, isoelectric focusing or HPLC showing FSA. Family or DNA studies may be used to confirm genotype.  

Clinical Expectations:   Infants are usually well at birth. Later potential clinical problems include mild hemolytic anemia, life-threatening infection, vaso-occlusive pain episodes, dactylitis, and chronic organ damage. Prompt treatment of infection and splenic sequestration is associated with decreased mortality in the first three years of life 

Additional Information: (Click on the name to take you to the website) 

Grady Comprehensive Sickle Cell Center                  Wyoming Department of Health
http://scinfo.org/                                                http://www.health.wyo.gov

Sickle Cell Disease Association                                Colorado Newborn Screening
http://www.sicklecelldisease.org/                           http://www.cdphe.state.co.us  

 

 

www.acmg.net

 

For Algorithm: http://www.acmg.net/resources/policies/ACT/Visio-Hemoglobinopathy_4-18-06.pdf