Coombs Test (Direct)

Antibodies are an essential component of our immune system. They help protect our bodies from infections, but sometimes they may attack the healthy cells of the body. Since all the red blood cells in the body are not alike, our immune system may produce antibodies against the ones that do not match the others. However, if the immune system cannot detect the infection correctly and starts producing antibodies against one’s cells, it can cause several health problems. The Coombs test detects the presence of antibodies that may attack the red blood cells. The Coombs test may help the doctor determine if the antibodies produced by the immune system are responsible for attacking and destroying one’s cells. Destruction of the red blood cells is referred to as hemolytic anemia. Of the two Coombs tests, the Direct Coombs test helps detect antibodies that are attached to the red blood cells. Otherwise known as the Direct Agglutination test, the Direct Coombs test is done more frequently. This is because the reagent used in the Coombs test causes the red blood cells with the attached antibodies to stick to each other. A Direct Coombs test can also be done to diagnose transfusion reaction and fatal conditions like erythroblastosis fetalis.