The test identifies IgG antibodies or complement (C3) bound directly to the surface of red blood cells.

A positive result indicates immune-mediated hemolysis.

Clinical uses include:

Diagnosing autoimmune hemolytic anemia (AIHA).

Investigating hemolytic transfusion reactions.

Detecting hemolytic disease of the newborn (HDN) due to maternal antibodies.

Monitoring patients with drug-induced hemolysis.

The test is performed by mixing patient RBCs with Coomb’s reagent (anti-human globulin); agglutination indicates a positive result.

Analyte: Antibodies (IgG) or complement proteins bound to red blood cells.

Normal Result: Negative (no agglutination).

Abnormal Findings:

Positive DCT: Indicates immune-mediated hemolysis (AIHA, transfusion reaction, HDN, drug-induced hemolysis).

Clinical Use:

Provides a direct measure of antibody/complement coating on RBCs.

Helps differentiate causes of anemia and hemolysis.

Guides treatment decisions in transfusion medicine and hematology.