Full-field electroretinogram behavior in Vogt-Koyanagi-Harada disease: a 24-month longitudinal study in patients from acute onset evaluated with multimodal analysis.

PURPOSE: To prospectively evaluate the dynamic changes of the full-field electroretinogram (ff-ERG) and its association with inflammatory signs in patients with Vogt-Koyanagi-Harada disease (VKHD) followed up after acute onset. METHODS: Twelve acute VKHD patients, who were followed up for at least 24 months, were enrolled at a tertiary center from June 2011 to January 2017. Treatment consisted of intravenous methylprednisolone followed by 1 mg/kg/day of oral prednisone with a slow tapering associated with late non-steroidal immunosuppressive therapy in previously defined cases. Inflammation was systematically evaluated with clinical and posterior segment imaging (PSI) exams (fluorescein angiography, FA, indocyanine green angiography, ICGA, enhanced depth imaging optical coherence tomography, EDI-OCT). A ff-ERG was performed upon enrollment as well as at predefined intervals. Scotopic ff-ERG parameters changes between the 12th and 24th months defined the ERG-stable or ERG-worsening groups. "Flare" was defined as an appearance or worsening of inflammatory signs (after the initial 6 months following disease onset) under the predefined treatment protocol. RESULTS: ff-ERG parameters initially improved in all eyes; in the evaluation between the 12th and 24th months, ff-ERG results were stable in 17 eyes (71 %) and worsened in 7 eyes (29 %). Subnormal ff-ERG results were observed in 15 eyes (62 %) at the 24th month. On the other hand, the flare was observed in 8 eyes (33 %) as cells in the anterior chamber and in 24 eyes (100 %) as any PSI inflammatory sign. The ERG-worsening group presented thicker subfoveal choroid at the first month (p = 0.001) and fluctuations in choroidal thickness more often during follow-up when compared to the ERG-stable group (p = 0.02). CONCLUSIONS: Scotopic ff-ERG parameters worsened between the 12th and 24th months in a quarter of the patients. Subclinical inflammation detected as an increase in CT seems to be related to worsening in visual function measured with ffERG.

Vogt-Koyanagi-Harada disease: review of a rare autoimmune disease targeting antigens of melanocytes.

Vogt-Koyanagi-Harada disease (VKHD) is a rare granulomatous inflammatory disease that affects pigmented structures, such as eye, inner ear, meninges, skin and hair. This disease is mainly a Th1 lymphocyte mediated aggression to melanocytes after a viral trigger in the presence of HLA-DRB1*0405 allele. The absence of ocular trauma or previous intraocular surgery sets VKHD appart from sympathetic ophthalmia, its main differential diagnosis. The disease has an acute onset of bilateral blurred vision with hyperemia preceded by flu-like symptoms. The acute uveitic stage is characterized by a diffuse choroiditis with serous retinal detachment and optic disc hyperemia and edema. Fluorescein angiography in this phase demonstrates multiple early hyperfluorescent points. After the acute uveitic stage, ocular and integumentary system pigmentary changes may appear. Ocular findings may be accompanied by lymphocytic meningitis, hearing impairment and/or tinnitus in a variable proportion of patients. Prompt diagnosis followed by early, aggressive and long-term treatment with high-dose corticosteroids is most often ensued by good visual outcomes. However, some patients may experience chronic uveal inflammation with functional eye deterioration. The current review discusses the general features of VKHD, including epidemiology, classification into categories, differential diagnosis and current therapeutic approaches.