Recurrence of Vogt-Koyanagi-Harada Disease as Immune-Related Adverse Events Induced by an Immune Checkpoint Inhibitor.

We describe a case involving recurrence of Vogt-Koyanagi-Harada (VKH) disease induced by treatment with the immune checkpoint inhibitor (ICI) pembrolizumab (anti-programmed death (PD)-1 antibody). The patient was a 59-year-old woman who presented with decreased vision in both eyes. She was referred to our hospital. In addition to anterior chamber inflammation, thickening of the choroid, folds in the retinal pigment epithelium (RPE) layer, and multiple serous retinal detachments were observed. Cerebrospinal fluid analysis revealed a significant increase in mononuclear cells, leading to a diagnosis of VKH disease. She received an intravenous infusion of 1,000 mg of methylprednisolone for three days; thereafter, she was started on 40 mg of oral prednisolone, which was gradually tapered off, and treatment was completed 18 months after the onset. One year later, the patient underwent tumor resection for endometrial cancer and was subsequently treated with the ICI anti-PD-1 antibody (pembrolizumab). She began noticing a decline in her vision, and a recurrence of VKH disease was noted. Thickening of the choroid, folds in the RPE layer, and serous retinal detachments were again observed in both eyes, leading to a diagnosis of recurrent VKH disease. While continuing pembrolizumab, the patient resumed oral prednisolone at 30 mg. As improvement was observed, the dose of prednisolone was gradually tapered; however, anterior chamber inflammation, thickening of the choroid, and RPE folds were subsequently noted, leading to a diagnosis of another recurrence. When administering an ICI to patients with a history of VKH disease, an ophthalmology consultation should be recommended both before and after initiating treatment.