Isolated adrenocorticotropic hormone (ACTH) deficiency and Guillain-Barré syndrome occurring in a patient treated with nivolumab.

The increased use of immune checkpoint inhibitors (ICIs) has led to the observation of a variety of immune-related adverse events (irAEs). These irAEs occur usually within the first months after ICIs onset and can involve theorically all organs. We describe two rare irAEs occurring in a 70-year-old caucasian man who was treated with nivolumab for an advanced urothelial cancer of the left kidney. He developed an isolated adrenocorticotropic hormone deficiency that was diagnosed at week 19 and a neurological complication that appeared at week 79 and initially confounded with a lumbar spinal stenosis. Diagnosis of Guillain-Barré syndrome was finally confirmed with the complete resolution of symptoms after 5 days of intravenous immunoglobulin and corticosteroids. We highlight the importance of quickly recognising these potential life-threatening irAEs such as cortisol insufficiency and neurologic adverse events whose initially presentation could be non-specific. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.