Osmotic Fragility, Erythrocyte
Test Mnemonic
OSMFER
CPT Codes
- 85555 - QTY (1)
Includes
- Osmotic Fragility
Performing Laboratory
ARUP
FDA Category
Laboratory Developed Test
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 5 mL | Whole blood | EDTA (Lavender) | Refrigerated | Specimens should be refrigerated within 30 minutes after collection. |
Alternate Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 5 mL | Whole blood | Sodium or Lithium heparin (Green) | Refrigerated | Specimens should be refrigerated within 30 minutes after collection. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL | Whole blood |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | Unacceptable |
| Refrigerated | 72 hours |
| Frozen | Unacceptable |
Days Performed
Mon - Fri
Turnaround Time
2 - 6 days
Methodology
| Name | Description |
|---|---|
| Spectrophotometry (S) |
Reference Range
Special Info
Grossly hemolyzed specimens are unacceptable. This test is New York DOH approved.
Clinical Info
Functional testing of red blood cell sensitivity to osmotic stress; do not use to distinguish between spherocytes in hereditary spherocytosis and acquired autoimmune hemolytic anemia. For patients with acute hemolysis, a normal red cell osmotic fragility test result cannot exclude an osmotic fragility abnormality since the osmotically labile cells may be hemolyzed and not present. Recommend testing during a state of prolonged homeostasis with stable hematocrit.