MLT GlobeSickling test
Hematology · also called Sickle cell screen, Sodium metabisulfite test, Solubility test
What it measures
A rapid screen for hemoglobin S. A reducing agent removes oxygen so cells containing HbS sickle (slide test) or the HbS precipitates and clouds the solution (solubility test).
Specimen and preparation
- Specimen: Whole blood (EDTA)
- Tube: Lavender top
- Preparation: Results may be false negative in infants under 6 months and after recent transfusion.
Reference range
| Group | Range |
|---|---|
| All | Negative |
Reference ranges differ between laboratories, methods and populations. Always use the range printed on your own lab report.
Causes of high values
- Positive: sickle cell trait (HbAS)
- Positive: sickle cell disease (HbSS, HbSC, HbS/β-thalassemia)
Method
Sodium metabisulfite slide test or dithionite tube solubility test
Good to know
A positive screen cannot tell trait from disease; confirm with Hb electrophoresis or HPLC. Severe anemia or high HbF may give false negatives.
Related tests
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