Tear analysis in multiple sclerosis.

We examined tears from 12 MS patients and 20 normal controls. In MS tears, the total IgG concentration was increased. Electrophoresis revealed low molecular weight bands (25 to 34k) in tears from patients with demyelinating optic neuritis; similar, less intense bands were seen in some patients with a history of optic neuritis. Production of tears was impaired in almost one-half of MS patients, especially in clinical exacerbations. Analysis of tears may offer new insight into immune function in MS, particularly of the mucosal immune system.