Rituximab-induced B-cell depletion has been proven to be a useful therapy for autoimmune hemolytic anemia (AIHA). The aim of this retrospective study was to evaluate the effectiveness of rituximab in the treatment of 36 patients with AIHA refractory to several treatments. These patients had received a median of four (one to eight) previous treatments, and 13 patients had undergone splenectomy. Rituximab was administered by intravenous infusion at a dose of 375 mg/m(2) once weekly for four doses in 29 patients, and 7 patients received one to six doses. Overall, 28 (77%) of 36 patients achieved response. Twenty-two patients (61%) reached a complete response (CR), and 6 patients (16%) obtained a partial response. All patients that reached CR (61%) were able to maintain the response during more than 6 months, with a median follow-up of 14 months (1-86 months). Sixteen patients maintained response for more than 1 year. The predictors of maintained response were achievement of CR and negative Coombs test result. Splenectomized patients showed a better response rate than those nonsplenectomized. Rituximab was well tolerated, and only one patient presented a transitory rash during infusion. Rituximab induced clinical responses in multitreated severe refractory both warm and cold AIHA patients with little toxicity, and consequently, this therapy should be considered as an early therapeutic option in this setting.