Serum immunoglobulins in acute anterior uveitis.

Serum levels of immunoglobulin A, G, and M were examined in 99 patients with acute anterior uveitis (AAU). The mean level of serum IgA was raised (p less than 0.001) in AAU patients when compared with healthy control subjects. The levels of serum IgG and IgM were not significantly different from those in the control group. The raised levels of serum IgA were found to occur predominantly in the HLA-B27 positive group of patients (p less than 0.001) and were highest in HLA-B27 positive patients with sacroiliitis or associated spondylarthritic diseases (p less than 0.001). The HLA-B27 negative group of AAU patients did not have a significantly raised mean serum IgA. The raised level of serum IgA in HLA-B27 positive AAU patients suggests that there has been a response to an environmental or infectious agent(s) acting across a mucosal tissue in these patients. This agent could be responsible for the initiation of the acute ocular inflammation.