Indirect Coombs test

Keywords: Indirect antiglobulin test


5 mL blood in plain tube.


Patient’s plasma incubated with test red cells; red cells washed, incubated with polyvalent anti-human globulin serum and observed for agglutination.


Detection of red cell (blood group) antibodies in serum. Screen for red cell antibodies in pregnancy and prior to compatibility testing (cross match).

Detection and definition of antibodies in immune haemolytic anaemia.

See also Blood group and antibody screen and Crossmatch.


Agglutination indicates presence of antibody (or complement) bound to red cell surface.


Klein HG and Anstee DJ. Mollison’s Blood Transfusion in Clinical Medicine. 12th ed.2014. Wiley-Blackwell.