Lung and liver sarcoidosis‐like reaction induced by tocilizumab

peer reviewedA drug‐induced sarcoidosis‐like reaction is a systemic granulomatous reaction indistinguishable from sarcoidosis and occurring in temporal relationship with a drug initiation. In this article, we report a patient who developed lung and liver granulomatous lesions following tocilizumab initiation for a giant cell arteritis. Infectious, toxic, neoplastic and inflammatory differential diagnoses were ruled out and lesions regressed after treatment cessation, leading to the diagnosis of tocilizumab induced sarcoidosis‐like reaction. We review the six cases reported so far and emphasize the value of a prompt diagnosis. Finally, we discuss the potential pathophysiological mechanisms underlying this rare reaction, which could help to better understand the pathophysiology of sarcoidosis