Nivolumab-associated immune-related filamentary keratitis

A woman in her late 50s presented to the ophthalmology clinic having bilateral eye pain and discharge for the last month. Her medical history was significant for lung adenocarcinoma, for which she was being treated with nivolumab. Filamentary keratitis was evident at the slit-lamp examination. Regardless of ophthalmic reasons, nivolumab was suspended. Prednisolone ointment was started, with a complete remission. We present a case of steroid-responsive filamentary keratitis triggered by nivolumab. We aim to highlight the importance of prompt ophthalmology referral and the use of therapies targeting ocular surface inflammation in immune checkpoint inhibition therapy.