Test ID: UNHB Hemoglobin Stability, Blood
Reporting Name
Hb Stability, BUseful For
Work-up of congenital hemolytic anemias
Specimen Type
Whole Blood EDTASpecimen Required
Only orderable as part of a profile or as a reflex. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-HBEL1 / Hemoglobin Electrophoresis Evaluation, Blood
-THEV1 / Thalassemia and Hemoglobinopathy Evaluation, Blood and Serum
-REVE2 / Erythrocytosis Evaluation, Blood
-MEV1 / Methemoglobinemia Evaluation, Blood
Specimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole Blood EDTA | Refrigerated | 7 days |
Reference Values
Only orderable as part of a profile or as a reflex. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-HBEL1 / Hemoglobin Electrophoresis Evaluation, Blood
-THEV1 / Thalassemia and Hemoglobinopathy Evaluation, Blood and Serum
-REVE2 / Erythrocytosis Evaluation, Blood
-MEV1 / Methemoglobinemia Evaluation, Blood
Normal (reported as normal [stable] or abnormal [unstable])
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
83068
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| UNHB | Hb Stability, B | 4639-1 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 9095 | Hb Stability, B | 4639-1 |
Clinical Information
Unstable hemoglobin disease is rare and may be caused by any of a large number of hemoglobin variants. They are inherited as autosomal dominant traits. The severity of the disease varies according to the hemoglobin variant; there may be no clinical symptoms, or the disease may produce a mild, moderate, or severe hemolytic anemia.
The stained peripheral blood smear shows anisocytosis, poikilocytosis, basophilic stippling, polychromasia, and sometimes, hypochromia. The reticulocyte count may be increased. Splenomegaly and Heinz bodies may also be present.
Interpretation
An abnormal or unstable result is indicative of a hemoglobin variant present. Other confirmatory tests should be performed to identify the hemoglobinopathy (HBEL1 / Hemoglobin Electrophoresis Cascade, Blood).
Clinical Reference
1. Hoyer JD, Hoffman DR. The thalassemia and hemoglobinopathy syndromes. In: McClatchey KD, Amin HM, Curry JL, eds. Clinical Laboratory Medicine. 2nd ed. Lippincott Williams and Wilkins; 2002:866-895
2. Benz EJ, Ebert BL. Hemoglobin variants associated with hemolytic anemia, altered oxygen affinity, and methemoglobinemias. In: Hoffman R, Benz EJ, Silberstein LE, et al. eds. Hematology: Basic Principles and Practice. 7th ed. Elsevier; 2018:608-615
3. Shean RC, Agarwal A, Rets AV. Unstable hemoglobin, a rare but significant cause of hemolytic anemia: Recognition of peripheral smear findings is crucial for diagnosis. Int J Lab Hematol. Published online December 15, 2025. doi:10.1111/ijlh.70043
Method Name
Only orderable as part of a profile or as a reflex. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-HBEL1 / Hemoglobin Electrophoresis Evaluation, Blood
-THEV1 / Thalassemia and Hemoglobinopathy Evaluation, Blood and Serum
-REVE2 / Erythrocytosis Evaluation, Blood
-MEV1 / Methemoglobinemia Evaluation, Blood
Isopropanol and Heat Stability
Day(s) Performed
Monday through Friday
Report Available
1 to 4 daysmml-benign-hematology-disorders