Díez-Feijóo, RamónRodríguez-Sevilla, Juan JoséFernández Rodríguez, M. ConcepciónFlores, SolangeRaya, CarmenFerrer, AnaColomo Saperas, Luis AlbertoSalar Silvestre, Antonio2022-09-202022-09-202022Diez-Feijóo R, Rodríguez-Sevilla JJ, Fernández-Rodríguez C, Flores S, Raya C, Ferrer A, Colomo L, Salar A. Case report: High doses of intravenous immunoglobulins as a successful treatment for late onset immune agranulocytosis after rituximab plus bendamustine. Front Immunol. 2022 Jan 10;12:798251. DOI: 10.3389/fimmu.2021.7982511664-3224http://hdl.handle.net/10230/54113Late onset neutropenia (LON) related to rituximab or rituximab plus chemotherapy is defined as an unexplained absolute neutrophil count of ≤1.5 × 109/L starting at least four weeks after the last rituximab administration. LON is infrequent and its pathophysiology remains unknown. There are no guidelines or consensus strategies for the optimal management of patients developing LON. The majority of the patients recover promptly with no specific treatment and only some cases need to be managed with granulocytic colony stimulating factor (G-CSF), usually with a rapid response. Here, we describe a 69-year-old patient with Waldenström's macroglobulinemia who presented a septic event in the context of severe LON after rituximab plus bendamustine. The diagnosed of agranulocytosis was established by bone marrow examination. Interestingly, anti-neutrophil antibodies bound to the patient's granulocytes were found suggesting an autoimmune mechanism. The patient did not respond to G-CSF but achieved a rapid response after high doses of intravenous immunoglobulins with full white blood cell recovery.application/pdfeng© 2022 Diez-Feijóo, Rodríguez-Sevilla, Fernández-Rodríguez, Flores, Raya, Ferrer, Colomo and Salar. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.info:eu-repo/semantics/articlehttp://dx.doi.org/10.3389/fimmu.2021.798251Waldenström’s macroglobulinemiaAgranulocytosisBendamustineImmunoglobulinRituximabinfo:eu-repo/semantics/openAccess