Successful Treatment of Lymphoplasmacytic Lymphoma/Waldenström Macroglobulinemia Complicated by Severe Autoimmune Neutropenia With Rituximab and Bendamustine

A 73-year-old woman was diagnosed with lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) with general fatigue and severe neutropenia. Although rituximab monotherapy was initiated, the neutrophil counts decreased within one week after rituximab administration. Subsequently, a combination of rituximab and bendamustine was initiated, and then her neutrophil counts became consistently within the normal range. The LPL/WM kept complete remission for two years. LPL/WM complicated with severe autoimmune neutropenia is rare. Rituximab and bendamustine brought strong lymphocyte depletion, leading to amelioration of autoimmune neutropenia. In this case, rituximab and bendamustine may have been active in patients with LPL/WM complicated with autoimmune disorders.