ダラツムマブ投与後に不規則抗体スクリーニングと交差適合試験が偽陽性となった1症例

False-positive Results in Irregular Antibody Screening and Crossmatching After Daratumumab Treatment：A Case Report

要旨

　抗CD38抗体薬は不規則抗体検査，交差適合試験に用いる間接抗グロブリン試験に干渉する。抗CD38抗体薬であるダラツムマブの最終投与4カ月後に行った不規則抗体検査と交差適合試験が偽陽性となった症例を経験したので報告する。抗CD38抗体薬使用後の患者の周術期には，事前にジチオトレイトール（dithiothreitol：以下，DTT）処理を行うなど，詳細な輸血前検査が必要である。

　Although the human anti-CD38 monoclonal antibody daratumumab is widely used in the treatment of multiple myeloma, its use can interfere with the indirect antiglobulin tests that are commonly used for irregular antibody screening and crossmatching, potentially leading to false-positive results. We present the case of a 41-year-old male in which false-positive results were obtained in both an irregular antibody screening and a crossmatching performed 4 months after the patient received daratumumab as treatment for multiple myeloma. This case highlights the importance of a cautious interpretation of indirect antiglobulin test results in patients treated with anti-CD38 antibodies. To mitigate the potential interference of these antibodies, the administration of dithiothreitol treatment before indirect antiglobulin tests are performed should be considered in similar cases.