The association of anti-r-HuEpo-associated pure red cell aplasia with HLA-DRB1*09-DQB1*0309

Background. Anti-r-HuEpo associated PRCA developed in patients received subcutaneous injection of r-HuEpo for treatment of renal anemia in chronic kidney disease. This adverse immunological effect of r-HuEpo causes sudden loss of r-HuEpo efficacy, low circulating reticulocyte count and bone marrow biopsy shows an absence of erythroid precursor cells with normal cell population of non-erythroid lineage. There are postulation cause of anti-r-HuEpo associated PRCA including genetic factor, immunogenicity factor, storage and handlings factor and formulation of r-HuEpo product. Previous observation of our report showed an aggregation of HLA-DRB1 * 09 in four anti-r-HuEpo associated PRCA cases. This allele is rare in Caucasian (<1%) but more common in Thai population (8.4–12.5%). This study was aimed to investigate the possible association between HLA-DRB1 * 09 or other specific HLA and anti-r-HuEpo associated PRCA.