Osmotic Fragility, Erythrocyte
Label Mnemonic: | ROSF |
Epic code: | LAB330 |
Downtime form: | Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
Commercial Mailout Laboratory
6240-8 RCP
356-8593
6240-8 RCP
356-8593
Specimen(s):
Whole Blood
Specimen
Instructions:
Refrigerate within 30 minutes of collection,
viable 72 hours only. Specimens should be received at reference
laboratory within 24 hours of collection; testing must be performed
within 72 hours of collection.
Collection Medium:
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Green top tube 10 mL (Na Heparin) Hospital Stores #907693 |
Alternate
Collection Media:
Light Green top tube (Lithium Heparin)
Minimum:
Preferred Minimum: 5 mL whole blood and TWO unfixed air-dried, and unstained smears Absolute Minimum: 1 mL whole blood and TWO unfixed, air-dried, and unstained smears
Rejection Criteria:
Grossly hemolyzed specimens.
Delivery Instructions:

Turn Around
Time:
1-5 days upon receipt at reference laboratory
Reference Range:
Within normal curve limits. A graph will accompany laboratory report.
Interpretive Data:
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.
Comments:
Deliver specimen to lab before 1200 (Sunday through Thursday
only)-referred to reference laboratory. Pertinent clinical information
should accompany the request. Analysis cannot be done on patients
transfused in the preceding three months since the presence of
transfused cells may render the interpretation ambiguous.
Methodology:
Spectrophotometry
CPT Code:
85555
See Additional Information:
Specimens Requiring Immediate Delivery
Specimens Requiring Immediate Delivery