Immunological abnormalities in patients with untreated retinal vasculitis.

Peripheral blood immunological features were assessed in 21 patients with clinical and angiographic evidence of retinal vasculitis (RV). Abnormalities of humoral and cellular immunity were frequent in this group of patients. Lymphopenia was the most common immunological abnormality, being present in 76% of patients at presentation (p less than 0.05). Peripheral blood T and B cells were decreased with a normal helper (OKT4) to suppressor (OKT8) T cell ratio in 11 patients tested (five with Behçet''s syndrome and six with idiopathic RV). Significantly increased concentrations of serum immune complexes were present in 55% of patients (p less than 0.05). Results of the present study indicate the frequent association of peripheral blood immunological abnormalities in patients with active RV and indicate the possible role of immunological mechanisms in its pathogenesis.