Anti IH: An antibody worth mention

Abstract

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.

Potential serological challenges caused by anti-IH antibody in the crossmatch laboratory

“…have described a similar instance of a clinically significant anti-IH antibody showing a broad TA. [ 5 ] In our example, the anti-IH antibody demonstrated a higher grade of reactivity pattern and broader TA with group O adult erythrocytes as against group A 1 adult cells. Further, there was reduced reactivity with group Oi (cord) cells as well as Oh (Bombay) cells, respectively.…”

Cold Agglutinin Disease: Improved Understanding of Pathogenesis Helps Define Targets for Therapy

“…While neutrophil aggregates and pseudo-neutropenia have been observed in rare cases of CAD [32,35], low platelet counts have not been reported. Rarely, the antigen specificity can be anti-i (little i), anti-Pr, or anti-IH [31,36,37].…”