MLT GlobeDirect antiglobulin test (DAT)
Hematology · also called Direct Coombs test, DCT
What it measures
Detects antibody or complement already attached to the patient's red cells in the body. It is used to investigate immune hemolysis, transfusion reactions and hemolytic disease of the newborn.
Specimen and preparation
- Specimen: Whole blood (EDTA)
- Tube: Lavender top
- Preparation: EDTA prevents in-vitro complement binding; clotted samples can give false positives.
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
- Autoimmune hemolytic anemia (warm or cold)
- Hemolytic transfusion reaction
- Hemolytic disease of the fetus and newborn
- Drug-induced immune hemolysis
- Positive in some healthy people or after IVIG
Method
Polyspecific anti-human globulin (then monospecific anti-IgG and anti-C3d) by tube or column agglutination
Good to know
A positive DAT does not prove hemolysis; correlate with hemoglobin, reticulocytes, bilirubin, LDH and haptoglobin.
Related tests
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