Osmotic Fragility, Erythrocyte
Also known as: OSM FRG
Use
The Osmotic Fragility, Erythrocyte test is a functional test that assesses the sensitivity of red blood cells to osmotic stress. It is used to evaluate conditions such as hereditary spherocytosis and autoimmune hemolytic anemia, in which red blood cells are more prone to osmotic lysis due to increased fragility. The test is particularly important for investigating hemolytic anemias and can provide supportive evidence for these conditions, although additional clinical and laboratory data is recommended for comprehensive assessment.
Special Instructions
It is recommended to test during a state of prolonged homeostasis with stable hematocrit to avoid false negatives in cases with acute hemolysis, where osmotically labile cells may already be hemolyzed and absent. Green (sodium or lithium heparin) or lavender (EDTA) tubes should be used for collection.
Limitations
A normal test result in patients with acute hemolysis does not rule out osmotic fragility abnormalities since already lysed cells may not be present in the sample. It is advised to perform the test under conditions of stable hemoglobin and hematocrit for accurate interpretation. The test does not differentiate between hereditary spherocytosis and acquired autoimmune hemolytic anemia solely based on laboratory findings.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 34964-7
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
5mL
Minimum Volume
1mL
Container
Green (sodium or lithium heparin) or lavender (EDTA)
Storage Instructions
Specimens should be refrigerated within 30 minutes after collection.
Causes for Rejection
Grossly hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | 72 hours |
| Frozen | Unacceptable |