|Values are valid only on day of printing.|
Detecting complement bound to RBC
Investigation of hemolytic anemia
Complement, in conjunction with IgM antibody, may be present on patient or donor (transfused) RBCs and may cause hemolysis. The antibody may be directed against self-antigens (autoimmune hemolysis), maternal antigens (hemolytic disease of the newborn), donor antigens (eg, alloimmune transfusion reaction), or drugs.
The presence of in vivo coating of RBC with complement can be demonstrated by the direct antiglobulin (Coombs) test.
If positive, reaction is graded (positive 1+ to 4+).
The presence or absence of red cell-bound complement is used in conjunction with other testing and clinical data to aid in the characterization of hemolysis as immune-mediated. Possible causes include autoimmune hemolytic anemia, drug-induced hemolysis, hemolytic disease of the newborn, and alloimmune reactions to recently transfused RBC.
No significant cautionary statements.