Loss and Reappearance of A Antigen After Chemotherapy Leading to Blood Group Discrepancy in Acute Myeloid Leukemia: A Case Report.

A male patient aged 11 years diagnosed with acute myeloid leukemia presented with complaints of fever, lethargy, and bleeding manifestations. On ordering red blood cells and platelet transfusion, his blood group was tested. Blood group discrepancy was observed in that forward grouping showed the O Rh D positive blood group and reverse grouping revealed the A Rh D positive. The patient's previous blood group record was O Rh D positive, and he had a transfusion history of O Rh D positive red blood cells and platelets in other hospital. Initial immunohematological workup results, including adsorption and heat elution, were consistent with the O Rh D-positive blood group, but further workups on follow-up after the commencement of chemotherapy showed that his original blood group was A Rh D positive, in which the A antigen expression was previously masked by the underlying disease condition of the patient. Hence, the correlation of laboratory results with clinical details and case history is an essential step in resolving such blood group discrepancies.