Abstract
Changes on the expression of Rh blood-group antigens have been observed when hematologic malignancies progressed. It is reported that mosaic uniparental isodisomy on chromosome 1 induces unusual Rh blood-group phenotypes, showing both RhD positive and RhD negative erythrocyte cell-populations. Here we report on the loss of E and c antigen-expressions during exacerbation of myelodysplastic syndrome (MDS), in which anti-E autoantibody was detected by indirect antiglobulin test (IAT) but not by direct antiglobulin test (DAT).
A 79-year-old Japanese female was admitted to our hospital to undergo a detailed examination and treatment of her pan-cytopenia in March, 2010. In the bone marrow abnormal erythroblasts were dominantly observed, and chromosomal analysis revealed complex aberrations, including monosomy 19, and trisomy 21. She was diagnosed with MDS (RAEB-1). Periodical transfusion was selected for medical treatment because of her advanced age. On first admission, the examination on blood cell type proved to be B type RhD positive, and antibodies to red blood cells were negative by IAT. On the 55th day after first admission, anti-E was detected by IAT; however, DAT was negative. At that time, reactivity of patient red blood cells was (w+mf) to both anti-E and anti-c. On day 83, anti-c was also detected by the Bromelin method. There was no abnormality in the short arm of chromosome 1 although many chromosomal aberrations were detected in her marrow cells with the G-banding method. Moreover, RHCE gene analysis of the day-55 sample showed normal RHC, RHc, RHE, and RHe with PCR-SSP, which showed that this phenotype was R1R2 (CcDEe).
These results indicate that decrease expression of E and c antigen is associated with the exacerbation of MDS in our patient.
