Immunologic basis for the pathogenesis of pterygium.

We examined surgically excised pterygial tissues from 26 patients for the various immunoglobulin classes by direct immunofluorescence. Of the 26 patients, 19 (73.1%) showed positive staining with goat anti-human IgG fluorescein-labeled antibody. Direct immunofluorescence with goat anti-human IgE fluorescein-labeled antibody was found in all 26 samples, varying in fluorescent intensity from 1+ to 4+. Routine histologic staining disclosed an infiltration of small lymphocytes and plasma cells into the pterygium. These results suggest that an immunologic mechanism, possibly Type 1 hypersensitivity, may contribute to the pathogenesis of pterygium.