Rituximab-Related Late-Onset Neutropenia in Kidney Transplant Recipients Treated for Antibody-Mediated Acute Rejection

Objectives: Kidney transplant is a new area for use of rituximab, which is being used to treat acute antibody-mediated rejection or as an induction agent in ABO-or HLA-incompatible grafts. We report on late-onset neutropenia in rituximab-treated kidney transplant recipients with antibody-mediated rejection. Materials and Methods: This observational prospective study was performed on kidney transplant recipients with clinically suspicious or biopsy-proven antibody-mediated rejection treated with plasmapheresis plus intravenous immunoglobulin with (cases) or without (controls) rituximab. Results: Compared with none of the controls, 4 of 6 patients (66.7%) in the rituximab-treated group experienced late-onset neutropenia 35 to 93 days after the last dose of rituximab. The course of neutropenia was complicated by endocarditis in 1 patient, resulting in his death just because of a lack of valvular surgery. Conclusions: Increased use of rituximab to treat antibody-mediated rejection among kidney transplant recipients requires attention to its late-onset adverse event, neutropenia. Although asymptomatic in some patients, kidney transplant recipients treated con-comitantly with plasmapheresis and mycophenolate mofetil are predisposed to hypogammaglobulinemia, and monitoring of patients for infections is required.