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HelpOrder Code RBCME Red Blood Cell Membrane Evaluation, Blood
Useful For
Investigation of suspected red cell membrane disorders, such as hereditary spherocytosis or hereditary pyropoikilocytosis
This test is not useful for hereditary elliptocytosis.
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| FRAGO | Osmotic Fragility | Yes, (Order FRAG) | Yes |
| SCTRL | Shipping Control Vial | No | Yes |
| HSEV | Spherocytosis Interpretation | No | Yes |
| BND3 | Band 3 Fluorescence Staining, RBC | No | Yes |
| SMPB | Peripheral Blood Smear Review | No | Yes |
Testing Algorithm
Osmotic fragility and eosin-5-maleimide binding (Band3) flow cytometry testing will always be performed. A normal shipping control is necessary to exclude false-positive results due to preanalytical artifact. Testing will be canceled if no shipping control is received or if the shipping control is abnormal. A consultative interpretation will be provided.
For more information see Benign Hematology Evaluation Comparison.
Special Instructions
Method Name
HSEV: Medical Interpretation
FRAGO: Osmotic Lysis
BND3: Flow Cytometry
SMPB: Consultant Review
Reporting Name
RBC Membrane Evaluation, BSpecimen Type
ControlWhole Blood EDTA
Whole Blood Slide
Shipping Instructions
Specimens must arrive within 72 hours of collection.
Necessary Information
Include recent transfusion information and most recent complete blood cell count results.
Metabolic Hematology Patient Information (T810) is strongly recommended, but not required, to be filled out and sent with the specimen. This information aids in providing a more thorough interpretation of test results. Ordering providers are strongly encouraged to complete the form and send it with the specimen.
Specimen Required
A whole blood EDTA specimen, an EDTA shipping control specimen, and 2 well-made peripheral blood smears (Wright stained or fixed in absolute methanol) are required for testing. The shipping control is used to evaluate whether a patient result has been compromised by handling conditions such as temperature, motion, or other transportation interferences. Temperature and handling extremes can adversely impact the integrity of the specimen.
Patient:
Specimen Type: Whole blood
Container/Tube: Lavender top (EDTA)
Specimen Volume: 4 mL
Collection Instructions:
1. Refrigerate specimen immediately after collection.
2. Send whole blood specimen in original tube. Do not aliquot.
3. Rubber band patient specimen and control vial together.
Patient:
Specimen Type: Slides
Container/Tube: Blood smears
Specimen Volume: 2 Well-made peripheral blood smears
Collection Instructions:
1. Prepare 2 peripheral blood smears from the EDTA tube collected from the patient.
2. Either stain the smear with Wright stain or fix the smear with absolute methanol prior to shipping.
Normal Shipping Control:
Specimen Type: Whole blood
Container/Tube: Lavender top (EDTA)
Specimen Volume: 4 mL
Collection Instructions:
1. Collect a shipping control specimen from a normal (healthy), unrelated, nonsmoking person at the same time as the patient.
2. Clearly hand write "normal control" on the outermost label.
3. Refrigerate specimen immediately after collection.
4. Send control specimen in original tube. Do not aliquot.
5. Rubber band patient specimen and control vial together. The control and patient specimens must be handled in the same manner from specimen collection to receipt in the testing laboratory.
Specimen Minimum Volume
Patient whole blood, shipping control: 2 mL; Slides: See Specimen Required
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Control | Refrigerated | 72 hours | PURPLE OR PINK TOP/EDTA |
| Whole Blood EDTA | Refrigerated | 72 hours | |
| Whole Blood Slide | Refrigerated | CARTRIDGE | |
Reject Due To
| Gross hemolysis | Reject |
| Clotted | Reject |
Reference Values
≥12 months:
0.50 g/dL NaCl (unincubated): 3-53% hemolysis
0.60 g/dL NaCl (incubated): 14-74% hemolysis
0.65 g/dL NaCl (incubated): 4-40% hemolysis
0.75 g/dL NaCl (incubated): 1-11% hemolysis
NaCl = sodium chloride
An interpretive report will be provided.
Reference values have not been established for patients who are younger than 12 months of age.
Method Description
Osmotic Fragility:
Specimens for erythrocyte osmotic fragility tests are anticoagulated with EDTA. Osmotic lysis is performed using sodium chloride solution, 0.5 g/dL. An incubated fragility test is performed following 24-hour incubation at 37° C at the following sodium chloride concentrations: 0.60, 0.65, and 0.75 g/dL. Results are reported and interpreted.(Larson CJ, Scheidt R, Fairbanks VF: The osmotic fragility test for hereditary spherocytosis: use of EDTA-anticoagulated blood stored at 4° C for up to 96 hours. Am Soc Clin Pathol Meeting Abstract, 1988; Larson CJ, Scheidt R, Fairbanks VF: The osmotic fragility test for hereditary spherocytosis: objective criteria for test interpretation. Am Soc Clin Pathol Meeting Abstract, 1988; King MJ, Zanella A: Hereditary red cell membrane disorders and laboratory diagnostic testing. Int J Lab Hematol. 2013 Jun;35(3):237-243)
Band 3/Eosin-5-Maleimide Binding Assay:
Eosin-5-maleimide (EMA) is a fluorescent dye that binds to Lys-430 of the extracellular loop of the band 3 protein. Using a 1-color flow cytometry method (number of events plotted against fluorescence), the fluorescent intensity of EMA-stained red blood cells is assessed and compared to normal-value patients.(King MJ, Behrens J, Rogers C, Flynn C, Greenwood D, Chambers K: Rapid flow cytometric test for the diagnosis of membrane cytoskeletal associated hemolytic anemia. Br J Haematol. 2000 Dec;111(3):924-933; King MJ, Zanella A: Hereditary red cell membrane disorders and laboratory diagnostic testing. Int J Lab Hematol. 2013 Jun;35(3):237-243)
Peripheral Blood Smear Review:
A hematopathologist who is an expert in these disorders evaluates the slides and an interpretive report is issued.
Day(s) Performed
Monday through Saturday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
85557-Osmotic fragility
88184-Flow cytometry; first cell surface, cytoplasmic or nuclear marker x 1
85060-Morphology review
Forms
1. Metabolic Hematology Patient Information (T810)
2. If not ordering electronically, complete, print, and send a Benign Hematology Test Request (T755) with the specimen.