Coombs Test

**Semantic type:** Laboratory Procedure

**Definition:** A hemagglutination test using anti-human globulin (antiglobulin, Coombs reagent) to detect antibodies that react with a subject's red blood cells. The test takes two forms: the direct test is used to diagnose autoimmune hemolytic anemia; the indirect test is used for prenatal Rhesus factor compatibility, blood and tissue typing, and transplant cross-matching.

**Synonyms:** - Coomb's test - Coombs - antiglobulin test