Anti IH: An antibody worth mention

A 72-year-old female with co-morbidities posted for surgical correction of fracture neck of femur without any history of transfusions was noted to have a hemoglobin level of 7 g/dl and packed red blood cells transfusion was ordered. Pretransfusion tests demonstrated A1B group with D positive on forward grouping. Reverse grouping showed a varying grade of agglutination with A, B, and O cells. Agglutination being stronger at 4°C. Antibody screening showed pan-agglutination, direct Coomb's test and auto control were negative. The serum reacted with adult O cells (OIadult) but not with adult Bombay cells (Oh Iadult) or O cord (Oicord) cells. A possibility of a compound cold antibody anti IH was made and A1B compatible cells were transfused to the patient. This case report illustrates anti-IH cold agglutinin with broad thermal amplitude. Uniqueness of this case report was O group incompatibility with A1B group, which was detected earlier and a catastrophic transfusion reaction being subverted.