Which serologic test is used to diagnose autoimmune hemolytic anemia?

Which serologic test is used to diagnose autoimmune hemolytic anemia?

• A. Coggins Test
• B. Intradermal Testing
• C. Latex Agglutination Test
• D. Coombs Test

Answer: (D)

Autoimmune hemolytic anemia is diagnosed by showing antibodies or complement bound to the patient’s red blood cells. The Coombs test, also called the antiglobulin test, is designed for exactly that purpose. A direct Coombs test uses anti-human globulin to detect antibodies or complement attached to red cells, and a positive result confirms immune-mediated coating of erythrocytes, which is what happens in AIHA. The indirect Coombs test can detect free antibodies in serum that could react with red cells, providing additional diagnostic information. Other options aren’t used to diagnose AIHA: the Coggins test screens for equine infectious anemia, intradermal testing is a skin allergy test, and latex agglutination is a general serologic method not specific to identifying immune coating of red cells.

Autoimmune hemolytic anemia is diagnosed by showing antibodies or complement bound to the patient’s red blood cells. The Coombs test, also called the antiglobulin test, is designed for exactly that purpose. A direct Coombs test uses anti-human globulin to detect antibodies or complement attached to red cells, and a positive result confirms immune-mediated coating of erythrocytes, which is what happens in AIHA. The indirect Coombs test can detect free antibodies in serum that could react with red cells, providing additional diagnostic information.

Other options aren’t used to diagnose AIHA: the Coggins test screens for equine infectious anemia, intradermal testing is a skin allergy test, and latex agglutination is a general serologic method not specific to identifying immune coating of red cells.