Risk factors for developing EBV-related B cell lymphoproliferative disorders (BLPD) after non-HLA-identical BMT in children

B cell lymphoproliferative disorders (BLPD) are relatively frequent after genotypically non-HLA-identical BMT, We performed univariate analysis to study which BMT-related variables were associated with an increased risk of developing BLPD, Sixty-five recipients of other than genotypically HLA-identical PM grafts were included in the study, Seventy-seven recipients of genotypically HLA-identical PM grafts served as a comparison group, BLPD occurred in nine of 65 children after non-HLA-identical BMT (14%) and in none of the 77 children after HLA-identical BMT (0%), In all cases, BLPD was proven to be EBV-related, Our data suggest that the combined use of Campath 1G and anti-LFA1 was associated with an increased risk of developing BLPD, particularly children who had received a T cell-depleted PM graft, using albumen density gradient sedimentation followed by E-rosetting, and who were conditioned with Ara-C, CY and TBI, In addition, T cell numbers below 50/mu l at 1 month and below 100/mu l at 2 months after BMT, respectively, were associated with an increased risk of developing BLPD, Longitudinal determination of T cell numbers after non-HLA-identical PMT is a simple method for identifying patients at risk of developing BLPD, In addition to monitoring levels of circulating EBV-infected lymphocytes, monitoring T cell numbers may allow early intervention to prevent progression of BLPD.