Direct Antiglobulin Test

General Information

Lab Name
Direct Antiglobulin Test
Lab Code
DAT
Epic Name
Direct Antiglobulin Test
Description

The Direct Antiglobulin Test (DAT) is a hemagglutination test using reagent antibodies to human IgG and complement components. When the antiglobulin reagent is combined with washed RBCs, the Fc portion of the coating antibody molecules will bind to the reagent forming a bridge between adjacent RBCs to produce visible agglutination. Agglutination by a monospecific reagent suggests that the RBCs are coated with the corresponding antibody protein. DAT testing may be performed on automated analyzer or standard tube method using polyspecific DAT reagent. Further testing with DAT IgG specific and Complement will be performed if reactivity noted with polyspecific DAT reagent.

Synonyms
DAT, Direct Coombs Test
Components

Interpretation

Reference Range
See individual components

Ordering & Collection

Specimen Type
Blood
Collection

Preferred: 6 mL PINK TOP (EDTA) tube

Also acceptable: 6 mL LAVENDER TOP tube

Handling Instructions

Specimen verification and collection

  • Verification of positive patient ID must be performed in the presence of the patient by the person collecting the specimen and a second qualified staff member at the time of collection and include a verbal read back of the full legal name, spelling of the legal name, and MRN as it appears on the armband.
  • Both persons performing the verification are required to sign the labeled sample documenting verification was performed and the specimen was collected from the correct patient.
  • Label specimen in the presence of the patient.
  • Write collection date and time on specimen label.
  • Signatures or initials of person collecting the specimen and second verifier are required on the specimen


Transport: Place specimen in separate biohazard bag and transport at room temperature

Transport temperature: Ambient

Quantity
Requested: 6 mL EDTA whole blood
Minimum: 3 mL EDTA whole blood

Processing

Receiving Instructions

For UWMC patients: send specimen to appropriate transfusion service lab. H location specimen will be sent to HMC, U location specimen will be sent to UWMC Montlake TSL.

For non UWMC clients: Specimen must be collected and tested at UWMC Montlake Transfusion Services Lab within 24 hours of collection. Testing will be performed at UWMC Montlake Transfusion Services. Batch and send specimen separate from other testing, indicate for “For Transfusion Services” on bag.

SPS: Receive batch from non UWMC clients and immediately send specimen to NN601, tube station: 361 for testing.

Misc Sendout

Performance

Lab Department
Blood Bank(BB)
Frequency
Daily
Available STAT?
No
Performing Location(s)
HMC Transfusion Service
206-520-4600

325 9th Ave, Rm # BCT-67, Seattle, WA 98104-2420

UW-MT Transfusion Service
206-520-4600

Clinical Lab, Room # NN601,
University of Washington Medical Center,
1959 NE Pacific street, Seattle, WA 98195

Billing & Coding

CPT Codes
86880
LOINC
1007-4
Interfaced Order Code
UOW5189