The effect of rituximab dose on infectious complications in ABO-incompatible kidney transplantation.

BACKGROUND: Rituximab (RIT) improves the outcomes of ABO-incompatible (ABOi) kidney transplantation (KT), but it has been associated with infectious complications. The aim of this study was to investigate infectious complications according to the dose of RIT in ABOi KT.

METHODS: We analyzed 213 recipients [118 ABO-compatible (ABOc) KT and 95 ABOi KT] who underwent living donor KT between 2010 and 2014. ABOi KT patients were categorized by RIT dose: standard RIT (375 mg/m(2), n = 76) versus reduced RIT (200 mg, n = 19). All patients received basiliximab and maintained on triple immunosuppression consisting of tacrolimus, prednisone and mycophenolate mofetil. Infectious complications and post-transplant outcomes were analyzed for 1 year following KT.

RESULTS: The rates of overall infectious complications among the three groups were comparable (22.9% in ABOc KT, 38.2% in standard RIT and 26.3% in reduced RIT, P = 0.069). In the standard RIT group, hepatitis B virus reactivation occurred in three recipients (3.9%) with hepatitis B surface antigen[-]/anti-hepatitis B core antibody[+]. Three cases (3.9%) of Pneumocystis jirovecii pneumonia occurred in the standard RIT group. Serious infections developed in 13 of the ABOc KT (11.0%), 20 from the standard RIT group (26.3%) and 2 from the reduced RIT group (10.5%, P = 0.015). Standard-dose RIT was found to be an independent risk factor for serious infections [hazard ratio: 2.59 (95% confidence interval: 1.33-5.07), P = 0.005]. There were no significant differences in rejection, renal function, graft survival and patient survival between standard and reduced RIT groups.

CONCLUSIONS: Standard RIT increased the risk of serious infection when compared with reduced-dose RIT. Reduced-dose RIT might be sufficient for ABOi KT without increasing the risk of serious infection.