Relapse of Birdshot Uveitis after Stopping Immunosuppressive Treatment and Starting Immune Checkpoint Inhibitors for Lung Cancer.

A 56-year-old Caucasian woman with birdshot uveitis had to stop immunosuppressive treatment with adalimumab due to metastatic squamous lung carcinoma. She was subsequently treated with chemotherapy and pembrolizumab, an immune checkpoint inhibitor (ICI). After stopping adalimumab and starting pembrolizumab, the patient had an inflammatory relapse of birdshot uveitis with macular oedema. Birdshot uveitis is triggered by an unknown antigen presented on the HLA-A29 molecule which activates cytotoxic T-cells. Although immunosuppressive therapy effectively stabilizes birdshot uveitis, it might induce a higher risk of developing cancer. Treatment with ICIs, on the other hand, might exacerbate birdshot uveitis by increasing anti-tumoural immune reaction and inducing off-target autoimmunity.