Atypical vogt-koyanagi-harada disease: diagnostic markers in a case with the unilateral presentation

Vogt-Koyanagi-Harada disease (VKHD) typically presents with bilateral ocular involvement, and unilateral cases are very rare; this may be due to subclinical involvement of the second eye.A 23-year-old female patient presented with blurred vision in her left eye.Fundus and optical coherence tomography (OCT) examination revealed no abnormal findings in the right eye, while choroidal folds extending between the optic disc and macula and increased choroidal thickness were observed in the left eye.Fundus fluorescein angiography (FFA) showed staining only at the left optic disc.In indocyanine green angiography (ICGA), diffuse hypofluorescent dark dots (HDD) were observed in the early phase, and isofluorescent dots in the late phase in both eyes.These findings were interpreted as acute VKHD-related bilateral diffuse choroiditis.Prompt initiation of corticosteroid and immunosuppressive therapy resulted in initial improvement; however, the disease relapsed after the patient discontinued treatment due to gastrointestinal side effects.OCT findings of internal limiting membrane (ILM) undulations in the right eye were interpreted as indicative of inflammation activation.After resuming systemic corticosteroid therapy and adding methotrexate and adalimumab, the patient\'s ocular condition improved, with no further signs of inflammation.This case highlights that unilateral involvement with atypical findings can occur during the acute phase of VKHD, emphasizing the importance of using advanced imaging techniques (OCT, FFA, and ICGA) for early and accurate diagnosis.