RESUMO
A 67-year-old man previously diagnosed with ulcerative colitis complained of difficulty in defecation and underwent balloon dilatation of rectum, but the procedure failed. The patient was transferred to a surgical department for further treatment. Before surgery, his red cells were typed A, Rh(D) positive. The antibody screening test was positive and the results of the identification tests were atypical. The reactivity was similar to anti-Le(b) antibody; however, the antibody showed panreactivity against papainized red cells. It showed stronger reactivity against O red cells than A Le(a−b+) red cells, and we concluded that the antibody was anti-Le(bH). After reexamination, his Lewis phenotype was found to be Le(a−b−). His FUT2 and FUT3 were analyzed to confirm his Lewis blood type, and c.59T>G and c.1067T>A variants were found on the FUT3. Therefore, the patient's Lewis blood type was concluded as Le(a−b−).