HLA-B and Absence of circulating granulocytes: Another 4 HLA alleles (HLA-B*38:02, HLA-B*27:05, HLA-DRB1*01:01 and HLA-DRB1*04:02) with frequencies less than 5% were also included in the analysis because of significant associations with drug-induced agranulocytosis that have been reported in the literatures16,19,21–23,26.