Immunocytologic findings in a case of Vogt-Koyanagi-Harada syndrome.

Background: Vogt-Koyanagi-Harada (VKH) syndrome is a form of chronic panuveitis that often has a poor long-term visual outcome. To the authors' knowledge, there have been only two previous reports describing immunocytologic findings in the eyes of patients with VKH syndrome, all studied in relatively late stages of the disease.
Methods: The authors performed immunocytologic studies on the enucleated eyes of a patient with active VKH syndrome, using monoclonal antibodies to mononuclear subsets, major histocompatibility antigens, and viral and treponemal agents, to better understand the pathophysiologic mechanisms underlying the disease. Emulsified chorioretinal tissue also was processed for viral isolation in tissue culture and for Treponema pallidum by rabbit inoculation studies.
Results: The dense uveal infiltrates in active VKH syndrome are composed predominantly of T lymphocytes and HLA-DR+ macrophages. Scattered T cells and plasma cells were present in the retina. In addition, nondendritic-appearing CD1 (Leu-6) positive cells were localized in the choroid, in close proximity to choroidal melanocytes. No microbial agents were identified.
Conclusion: Whereas the etiology of the VKH syndrome remains an enigma, the authors' immunocytologic findings are consistent with a T-cell-mediated disorder. In demonstrating CD1 (Leu-6) positive cells in the infiltrates, the authors propose a potential role for these cells in the etiology of VKH syndrome.