Hemoglobin (Hb) A2 and F by Column with Reflex to Electrophoresis
Ordering Recommendation
Use to quantify HbA2 and HbF in whole blood. Aids in the management of sickle cell disease and in the identification of β thalassemia carriers.
New York DOH Approval Status
Specimen Required
Lavender (EDTA) or pink (K2EDTA).
Transport 5 mL whole blood. (Min: 0.2 mL)
Refrigerated.
Frozen or room temperature specimens.
Ambient: Unacceptable; Refrigerated: 1 week; Frozen: Unacceptable
Methodology
High Performance Liquid Chromatography (HPLC)/Electrophoresis
Performed
Sun-Sat
Reported
1-4 days
Reference Interval
Age-Defined Normal Hemoglobin Reference Intervals
Age |
Hb A2 Percent |
Hb F Percent |
---|---|---|
0-1 month | 0.0-1.4 | 45.8-91.7 |
2 months | 0.0-2.0 | 32.7-85.2 |
3 months | 0.1-2.6 | 14.5-73.7 |
4 months | 0.8-3.0 | 4.2-56.9 |
5 months | 1.5-3.3 | 1.0-38.1 |
6-8 months | 1.8-3.5 | 0.9-19.4 |
9-12 months | 1.9-3.5 | 0.6-11.6 |
13-23 months | 1.9-3.5 | 0.0-8.5 |
2 years and older | 2.0-3.5 | 0.0-2.1 |
Interpretive Data
In laboratory testing to confirm a diagnosis of a β-thalassemia trait diagnosis, Hb A2 levels should be considered in conjunction with family history and additional laboratory data, including serum iron and iron binding capacity, red cell morphology, hemoglobin, hematocrit, and mean corpuscular volume (MCV).
Patients with a combination of iron deficiency and β-thalassemia may have a normal A2 level. In these cases, elevated A2 level cannot be used to screen for β-thalassemia in these cases.
Patient State | Hb A2 Level | Hb F Level |
---|---|---|
Heterozygous β-thalassemia | 4-9% | 1-5% |
Homozygous β-thalassemia | Normal or Increased | 80-100% |
Heterozygous HPFH | Less than 1.5% | 10-20% |
Homozygous HPFH | Absent | 100% |
FDA
Note
Recommend quantitation of hemoglobin for definitive diagnosis after 1 year of age. If abnormal peaks suggestive of a hemoglobin variant are detected, then Capillary Electrophoresis will be added to aid in confirmation and identification of the variant. Additional charges apply
Hotline History
CPT Codes
83021; if reflexed, add 83020
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2008793 | Hemoglobin, Capillary Electrophoresis | 13514-5 |
3002709 | Hemoglobin A2 | 4551-8 |
3002710 | Hemoglobin F | 4576-5 |
3002711 | Hemoglobin A2 and F Interpretation | 21026-0 |
Aliases
- A2 Hemoglobin
- F-Hemoglobin
- Hemoglobin A2
- Hemoglobin A2 and F, Blood
- Hemoglobin F
- Hemoglobinopathy (Hb) A2