Hemoglobin, Unstable
Ordering Recommendation
Use to confirm unstable nature of hemoglobins. Test cannot be used on infants <6 months of age due to physiologically elevated Hb F levels.
New York DOH Approval Status
Specimen Required
Test results are unreliable in infants younger than 6 months of age.
Lavender (EDTA) or pink (K2EDTA).
DO NOT FREEZE. Transport 5 mL whole blood. (Min: 2 mL)
Refrigerated.
Samples more than 7 days old. Specimens collected on infants less than 6 months old.
Ambient: Unacceptable; Refrigerated: 7 days; Frozen: Unacceptable
Methodology
Visual Identification
Performed
Mon-Fri
Reported
1-5 days
Reference Interval
Negative
Interpretive Data
Unstable hemoglobin disease is due to an alteration in the amino acid sequence involved in the interface between the alpha
and beta chains of the hemoglobin molecule. These alterations significantly change the structure of the molecule resulting in
denaturation and precipitation of globin chains.
The Unstable Hemoglobin assay is a qualitative test that does not identify the variant when present. Additional evaluation is
suggested for positive tests (Hemoglobin Evaluation by HPLC with Reflex to Electrophoresis and/or RBC Solubility, ARUP test
3017101). False positive results can occur in specimens with high hemoglobin F levels (infants less than 6 months old) and
specimens tested beyond 7 days from draw time.
Standard
Note
Hotline History
CPT Codes
83068
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0049020 | Hemoglobin, Unstable | 4639-1 |
Aliases
- Hb Heat Sensitivity
- Heat Stability Test
- Isopropanol Stability Test
- RBC Heat Stability Test
- Unstable Hemoglobin