Ibrutinib-induced Interstitial Pneumonia and Pneumomediastinum in a Patient with Chronic Graft-Versus-Host Disease

We describe the case of a 17-year-old man with severe aplastic anemia who had received allogeneic hematopoietic stem cell transplantation (HSCT) at the age of 15. He developed moderate chronic graft-versus-host disease of the skin, and ibrutinib was initiated 6 months after HSCT. At 21 months post-HSCT, the patient presented with dyspnea. A chest computed tomography scan revealed mediastinal and subcutaneous emphysema. Ibrutinib was discontinued, and steroid therapy was administered for the treatment of suspected interstitial pneumonia caused by ibrutinib exposure. The mediastinal and subcutaneous emphysema had disappeared, and no recurrence was observed thereafter. If any respiratory symptoms are observed during ibrutinib therapy, imaging studies should be performed to determine whether ibrutinib-related lung complications have occurred.