Detection of Clinically Significant Anti-Ih Antibodies in a Para-Bombay Patient During Pregnancy

Introduction: The para-Bombay blood phenotype is a rare blood group variant, with a limited number of cases reported worldwide. Case Summary: Here, we present the case of a pregnant woman with clinically significant anti-IH antibodies and incompatible cross-matching with group O packed cells detected during pre-transfusion testing. Three years later, samples were collected again from the subject and showed that her anti-IH antibody levels had reduced. Her para-Bombay blood type was then confirmed using a polymerase chain reaction with sequence-specific primers of the ABO gene and Sanger sequencing of the FUT1 and FUT2 genes. This patient can only undergo transfusion therapy with Bombay or para-Bombay matched blood group RBCs due to the pre-formed anti-IH in her serum. Conclusion: The systematic identification of blood groups and antibodies helped prevent transfusion-related adverse events and contributed to safe transfusion practice.