Clinical information
Diagnostic Utility:
This test detects the presence of IgG antibodies or the complement component C3d coating red blood cells. This situation may occur, fundamentally, in the context of:
- Autoimmune hemolytic anaemia.
- Drug-induced hemolytic anaemia.
- Hemolytic transfusion reactions.
- Feto-maternal incompatibility and hemolytic disease of the newborn.
Method:
Direct antiglobulin test (Direct Coombs test) with polyspecific antiglobulin. Hemagglutination.
Reference Values
Possible results are: Negative, Positive.
Diagnostic Algorithm:
In case of a positive result, test 9993 Differential direct Coombs is performed, which allows differentiation between IgG- and C3d-coated red blood cells.
| Code | Test Name | Can it be ordered separately? | Is it always done? |
|---|---|---|---|
| 9993 | Differential direct Coombs | Yes (*) | No |
*Although these tests can be ordered separately, the laboratory needs to know that the sample has a positive Direct Coombs. That's why a polyspecific Direct Antiglobulin Test is always performed initially.
Turnaround Time:
1 day when the screening is negative.
1 day when the screening is positive and identification is unequivocal.
Several days may be needed when the identification is complex (mixtures of antibodies or uncommon specificities)
Specimen information
Sample: Whole blood
Tube: EDTA K3 10 ml tube
Minimum volume: 6 ml (1 ml in infants)
Stability:
- At room temperature: 2 days
- In refrigeration: 2 days
Transport instructions: Preferably at room temperature
Reason for rejection: Sample highly hemolyzed
Administrative information
BST Code: 0012
Test Description: Direct Antiglobulin Test (DAT) Synonyms: Direct Coombs Test
Section: Immunohematology
BST Rate: Check the updated rates by clicking here.
Profiles:
Test 0012 Direct Antiglobulin Test can be requested individually. It is also performed within the following profiles:
| Profile | Included Tests |
|---|---|
| Hemolytic Anaemia |
0009 ABO/Rh(D) Blood Grouping 0010 Irregular Antibody Screen 0011 Irregular Antibody Identification 0012 Direct Antiglobulin Test 0014 Eluate of Red Cell Antibodies 0016 Auto/Allo Adsorption of Red Cell Antibodies 9991 Hemolytic Anaemia Comment |
| Feto-Maternal (Child) Incompatibility Study |
0009 ABO/Rh(D) Blood Grouping 0012 Direct Antiglobulin Test 0014 Eluate of Red Cell Antibodies 9994 Incompatibility Comment |
| Haemolytic Disease of the Newborn (Infant) |
0009 ABO/Rh(D) Blood Grouping 0012 Direct Antiglobulin Test Note: The mother should also be studied |
References
AABB Technical Manual. 19th edition. Editat per MK Fung, AF Eder, SL Spitalnik, CM Westhoff: AABB 2017
Quality
BST holds ISO 9001, ISO 14001, and OSHAS 18001 quality certifications, as well as the European Excellence 500+ seal. BST is accredited by CAT, JACIE-FACT, FACT-NETCORD, and EFI, and complies with Good Manufacturing Practice (GMP) and Good Distribution Practice (GDP) guidelines.