INTRODUCTION: Most anti-M antibodies are not active at 37°C and are thus of no clinical significance. Occasionally these antibodies have a wide thermal range and can lead to hemolytic transfusion reactions or hemolytic disease of the new born. PATIENT AND METHODS: We describe two cases of anti-M antibodies, both of which were clinically significant. RESULTS: The first case was detected due to crossmatch incompatibility and the second presented as a blood group discrepancy. CONCLUSION: When the antibody is active at 37°C, M antigen negative red cell units should be issued.
INTRODUCTION: Most anti-M antibodies are not active at 37°C and are thus of no clinical significance. Occasionally these antibodies have a wide thermal range and can lead to hemolytic transfusion reactions or hemolytic disease of the new born. PATIENT AND METHODS: We describe two cases of anti-M antibodies, both of which were clinically significant. RESULTS: The first case was detected due to crossmatch incompatibility and the second presented as a blood group discrepancy. CONCLUSION: When the antibody is active at 37°C, M antigen negative red cell units should be issued.