A case of coagulation factor V inhibitor induced by immune checkpoint inhibitor therapy

In recent years, the use of immune checkpoint inhibitors (ICIs) for the treatment of various carcinomas has increased, which have been associated with immune-related adverse events (irAEs) that are often diverse. Haematological immune-related adverse events (hem-irAEs) are rare, and only a few cases of ICI-induced coagulation factor inhibitors have been reported. Here, we report a rare case of ICI-induced factor V inhibitor. AbstractA 73-year-old woman with lung adenocarcinoma (cT4N3M1a: Stage IVA) was treated with atezolizumab as the eighth line of therapy. Four weeks after the fourth dose of atezolizumab, the prothrombin time (PT) and activated thromboplastin time (APTT) were prolonged. Coagulation factor V (FV) activity was decreased, and FV inhibitors were observed. There was no history of PT or APTT prolongation or bleeding before the use of atezolizumab. Atezolizumab-induced coagulation FV inhibitor was diagnosed. After 2  weeks, the PT and APTT spontaneously normalized. FV activity improved and the FV inhibitors disappeared after 6 and 9 weeks, respectively.

Source: Respirology Case Reports - February 15, 2024 Category: Respiratory Medicine Authors: Yuki Haruta, Masanori Azuma, Toshikatsu Sado, Ryuichi Saito, Yoshimune Miyazaki, Akihiro Noda, Reina Kitagawa, Yasutaka Hori, Sayaka Fujimoto, Yoshinori Hasegawa, Tetsuya Ueda, Ryosuke Yamamura Tags: CASE REPORT Source Type: research