Dou Xuelin, Li Kongyang, Lu Jin
Department of Hematology, Peking University People's Hospital, National Clinical Research Center for Hematologic Diseases, Peking University Institute of Hematology, Beijing, China.
Department of Hematology, People's Hospital of Yangjiang, Yangjiang, China.
Front Oncol. 2024 Dec 17;14:1509567. doi: 10.3389/fonc.2024.1509567. eCollection 2024.
Obinutuzumab, a humanized type II anti-CD20 monoclonal antibody, is widely used in the treatment of B-cell lymphomas. Thrombocytopenia typically occurs 1 to 2 weeks after administration. In rare cases, obinutuzumab can induce severe acute thrombocytopenia within days of infusion, a condition known as "obinutuzumab-induced acute thrombocytopenia (OIAT)." Rituximab, a chimeric type I anti-CD20 monoclonal antibody, is also known to cause "rituximab-induced acute thrombocytopenia (RIAT)." This report presents a case of OIAT, with subsequent treatment switched to rituximab, which did not result in thrombocytopenia recurrence.
A 38-year-old female patient with a 2-year history of lymphadenopathy was diagnosed with follicular lymphoma (Grade I-II). She was treated with obinutuzumab combined with bendamustine. Following the first administration of obinutuzumab, her platelet count dropped to 37×10⁹/L within 2 days and further declined to 27×10⁹/L on the fourth day without bleeding symptoms. The platelet count recovered by day 8. After a second obinutuzumab infusion, the platelet count again dropped to 15×10⁹/L within 1 day. Platelet transfusion was effective, and the count eventually recovered to 95×10⁹/L by day 29. No further acute thrombocytopenia occurred after switching to rituximab.
OIAT is a rare but serious adverse effect of obinutuzumab. This case highlights the importance of early recognition and monitoring of platelet counts in patients receiving obinutuzumab. The findings in our case, along with those in the literature, suggest that switching to rituximab or extending the interval before obinutuzumab re-administration can reduce the risk of recurrent thrombocytopenia. Further research is needed to elucidate the underlying mechanisms and establish treatment guidelines for OIAT.
奥妥珠单抗是一种人源化II型抗CD20单克隆抗体，广泛用于治疗B细胞淋巴瘤。血小板减少症通常在给药后1至2周出现。在罕见情况下，奥妥珠单抗可在输注数天内诱发严重急性血小板减少症，这种情况称为“奥妥珠单抗诱导的急性血小板减少症（OIAT）”。利妥昔单抗是一种嵌合I型抗CD20单克隆抗体，也已知会引起“利妥昔单抗诱导的急性血小板减少症（RIAT）”。本报告介绍了一例OIAT病例，随后改用利妥昔单抗治疗，未导致血小板减少症复发。
一名38岁女性患者，有2年淋巴结病病史，被诊断为滤泡性淋巴瘤（I-II级）。她接受了奥妥珠单抗联合苯达莫司汀治疗。首次使用奥妥珠单抗后，她的血小板计数在2天内降至37×10⁹/L，并在第4天进一步降至27×10⁹/L，无出血症状。血小板计数在第8天恢复。第二次输注奥妥珠单抗后，血小板计数在1天内再次降至15×10⁹/L。血小板输注有效，计数最终在第29天恢复至95×10⁹/L。改用利妥昔单抗后未再发生急性血小板减少症。
OIAT是奥妥珠单抗一种罕见但严重的不良反应。该病例突出了在接受奥妥珠单抗治疗的患者中早期识别和监测血小板计数的重要性。我们病例的发现以及文献中的发现表明，改用利妥昔单抗或延长奥妥珠单抗再次给药前的间隔时间可降低血小板减少症复发的风险。需要进一步研究以阐明潜在机制并建立OIAT的治疗指南。
