| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Sickle Cell Screen
MessageHematology
Test Code
LAB339
Alias/See Also
Sickle prep, Dithionite test, Sickledex, Hemoglobin S Solubility
CPT Codes
85660
Preferred Specimen
2.5 mL whole blood in lavender top tube, EDTA
Test may be performed on same tube as CBC collection.
Test may be performed on same tube as CBC collection.
Minimum Volume
0.5 mL whole blood in microtainer (lavender top tube, EDTA), fingerstick/heelstick – Neonates
Other Acceptable Specimens
One Lavender-top K2EDTA Microtainer® (Min: 300 mcL), Gray-top Sodium or Potassium Oxalate tube, Light Blue-top Sodium Citrate tube, Dark Green-top Heparin tube, Yellow-top ACD tube, or a tube containing CPD or CPDA-1.
Instructions
LAB: Hematocrit of the sample must be ≥ 15%
If the hematocrit is below 15%:
Centrifuge the sample for 5-10 minutes at 1200 rpm.
Pipet 10µl of the packed cell volume from the bottom of the tube
Add it to the Sickledex® Solubility Buffer test tube.
If the hematocrit is below 15%:
Centrifuge the sample for 5-10 minutes at 1200 rpm.
Pipet 10µl of the packed cell volume from the bottom of the tube
Add it to the Sickledex® Solubility Buffer test tube.
Transport Container
Whole blood or capillary blood at room temperature (20-26°C or 68-78.8°F) or refrigerated (2-8°C or 36-46°F). (Min: 2.0 mL whole blood or 300 mcL capillary blood)
Specimen Stability
Refrigerated (2-8°C): 45 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Insufficient volume.
Frozen specimens.
Samples submitted for patients previously determined to have a positive sickle cell test.
Frozen specimens.
Samples submitted for patients previously determined to have a positive sickle cell test.
Methodology
Sickledex method is a qualitative test and does not distinguish between Sickle Cell Disease (S/S) and heterozygous Hgb S syndromes (e.g., A/S, C/S, etc.), all positive tests should be further evaluated by hemoglobin electrophoresis.
FDA Status
Moderately complex
Setup Schedule
Sunday - Saturday.
Report Available
Same day
Limitations
False negatives may occur if:
1. Hgb S concentration is low in infants younger than 6 months of age (due to the presence of Hgb F) and in transfused patients where the Hgb S is diluted below 30%.
2. Anemia (Hgb < 15%).
3. Hgb S concentration is low in infants younger than 6 months of age (due to the presence of Hgb F) and in transfused patients where the Hgb S is diluted below 30%.
4. Anemia (Hgb < 15%). Abnormal proteins, abnormal elevations of total serum proteins (particularly gamma globulins), and hyperlipidemia.
5. Hgb CHarlem, Hgb CGeorgetown, Hgb STravis, and Hgb CZiguinchor.
6. Transfusions with Hgb S blood.
7. Extremely high hemoglobin, erythrocyte count, or leukocyte count.
8. Many Heinz bodies in unstable hemoglobin disorders after splenectom
1. Hgb S concentration is low in infants younger than 6 months of age (due to the presence of Hgb F) and in transfused patients where the Hgb S is diluted below 30%.
2. Anemia (Hgb < 15%).
3. Hgb S concentration is low in infants younger than 6 months of age (due to the presence of Hgb F) and in transfused patients where the Hgb S is diluted below 30%.
4. Anemia (Hgb < 15%). Abnormal proteins, abnormal elevations of total serum proteins (particularly gamma globulins), and hyperlipidemia.
5. Hgb CHarlem, Hgb CGeorgetown, Hgb STravis, and Hgb CZiguinchor.
6. Transfusions with Hgb S blood.
7. Extremely high hemoglobin, erythrocyte count, or leukocyte count.
8. Many Heinz bodies in unstable hemoglobin disorders after splenectom
Reference Range
Negative
Performing Laboratory
Hoag Newport
