Incidence and predictive factors for infectious disease after rituximab therapy in kidney-transplant patients.

Rituximab off-label use includes organ transplantation. We review the occurrence of infectious disease and its outcome after rituximab therapy. Between April 2004 and August 2008, 77 kidney-transplant patients received rituximab therapy [2-8 courses (median 4) of 375 mg/m2 each] for various reasons. Their results were compared with a control group (n=902) who had received no rituximab. After a median follow-up of 16.5 (1-55) months for rituximab patients and 60.9 (1.25-142.7) months for control patients, the incidence of infectious disease was 45.45% and 53.9% (ns), respectively. The incidence of bacterial infection was similar between the two groups, whereas the viral-infection rate was significantly lower, and the rate of fungal infection was significantly higher in the rituximab group. Nine out of 77 patients (11.68%) died after rituximab therapy, of which seven deaths (9.09%) were related to an infectious disease, compared to 1.55% in the controls (p=0.0007). In the whole population, the independent predictive factors for infection-induced death were the combined use of rituximab and antithymocyte-globulin given for induction or anti-rejection therapy, recipient age, and bacterial and fungal infections. After kidney transplantation, the use of rituximab is associated with a high risk of infectious disease and death related to infectious disease.