Laboratory Lab results are too important to go anywhere else.

Hemoglobinopathy Evaluation

hemoglobin electrophoresis

Test Codes

Antrim #21245, EPIC: LAB5862, SOFT: HGEVL

Department

Special Chemistry

Instructions

A Complete Blood Count (CBC) is required to perform a Hemoglobinopathy Evaluation. Therefore, if a CBC has not been performed within the last 30 days, a CBC will be ordered.

Specimen Collection Criteria

Collect: One Lavender-top EDTA tube for Hemoglobinopathy Evaluation AND one Lavender-top EDTA tube for Complete Blood Count. (Minimum Whole Blood: 1.0 mL each tube.)

NOTE: The second Lavender-top EDTA tube is not required if a Complete Blood Count (CBC) or CBC with Differential (CBCD) is ordered and drawn at the same time, or has been performed in the last 30 days. If there is not a separate order for a CBC, and CBC will be ordered.

• A copy of the requisition must be sent with the specimen.
• See Minimum Pediatric Specimen Requirements for Microtainer^® collection.

Physician Office/Draw Specimen Preparation

Do not centrifuge. Do not freeze. Store whole blood refrigerated (2-8°C or 36-46°F) prior to transport. (Minimum Whole Blood: 1.0 mL each tube.)

Preparation for Courier Transport

Transport: Whole blood specimen or packed cells, refrigerated (2-8°C or 36-46°F). (Minimum Whole Blood: 1.0 mL each tube.)

Rejection Criteria

• Frozen specimens.
• Centrifuged specimens.
• Severely hemolyzed specimens.

In-Lab Processing

Do not centrifuge. Do not freeze.

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 48 hours
Refrigerated (2-8°C or 36-46°F): 3 days
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days

Laboratory

Royal Oak Special Testing Laboratory

Performed

Sunday – Saturday (day shift only). 
Confirmation of Hemoglobin variant by electrophoresis performed on Thursday.
Results available in 3–5 business days.

Reference Range

Hemoglobin	Age	Reference Range (%)
Hb A2	Less than 12 months	0.0 - 3.3
Hb A2	1 year – Adult	2.0 - 3.3
HbF	0-30 days	60 - 90
HbF	31 days – 23 months	Less than or equal to 60
HbF	2 years – Adult	0.0 - 2.0
HbA	0-30 days	10 - 40
HbA	31 days – 24 months	40 - 98.5
HbA	2 years – Adult	94.5 - 98.5

Test Methodology

Electrophoresis and High Performance Liquid Chromatography (HPLC).

The lab protocol consists of automatic chromatographic analysis (HPLC) to quantitate Hgb A₂, fetal hemoglobin and Hgb A. If an abnormal hemoglobin is identified by chromatography, electrophoresis (alkaline and/or acid gel) will be performed to confirm the identity of the variant hemoglobin. If an abnormal hemoglobin is not identified, electrophoresis will not be performed routinely.

Interpretation

The final interpretation is made by a pathologist.

Our current methods allow for detection of a number of hemoglobins including Hemoglobin S, C, D, E, Hasharon, Lepore, some A₂ variants and usually G Philadelphia. It can also be determined whether an individual is heterozygous or homozygous for the hemoglobin variant. Because of the great number of hemoglobin variants, the Beaumont Laboratory is unable to identify all possible variants and in some cases the blood sample or an additional sample is sent to Mayo Medical Laboratories. Based on hemoglobin A₂ and F levels and CBC results, diagnoses of ß (beta) or delta-ß (delta-beta) thalassemia (hetero or homozygous) can be made.

Hbg A₂ is elevated in ß thalassemia trait, although if a patient has co-existing iron deficiency, the Hgb A₂ level may be normal. Hgb A₂ levels are also elevated in sickle cell trait, sickle cell disease, megaloblastic anemia and hyperthyroidism. Only ß thalassemia (hetero or homozygous) would be associated with thalassemic CBC indices (low MCV, high or high-normal RBC). Hgb A₂ levels are low or low-normal in alpha thalassemia, delta thalassemia, iron deficiency and sideroblastic anemia.

Hgb F levels are much higher in the neonate than an older child or adult. Hgb F may be slightly increased in ß thalassemia trait and moderately increased in delta-beta thalassemia. It is also increased in hereditary persistence of fetal hemoglobin, a condition most commonly seen in African-Americans. Slight increases may also be acquired and can occur with several bone marrow abnormalities (e.g., leukemias, aplastic anemia), severe anemias and in pregnancy.

Clinical Utility

Hemoglobin electrophoresis is usually ordered for detection of abnormal hemoglobins, ß thalassemia, and hereditary persistence of fetal hemoglobin (HPFH). It cannot be used to detect alpha thalassemia trait in individuals over a few weeks of age.

CPT Codes

83021. If reflexed, add 83020.

Contacts

Last Updated

1/11/2023