[An immuno-pathological study of pterygium].

Pterygium specimens from 68 patients and normal conjunctiva from 12 controls were examined for the contents of immunoglobulins and C3 by direct immunofluorescence assay. The levels of IgE, IgG and IgA in the epithelial layer, of IgE, IgG and C3 in the basement membrane, and of IgE, IgG in the stroma, were found significantly higher in progressive cases than in the controls. as was the IgG-bearing cell count in the stroma. Also IgG bound to the basement membrane was significantly manifest in the quiescent cases. Routine histologic staining showed an infiltration of lymphocytes and plasma cells in the pterygium. A small amount of immunoglobulins was found in the stroma from the controls, but no C3 was demonstrated. These results suggest that an immunologic mechanism, possibly type I and type III hypersensitivity, may contribute to the pathogenesis of pterygium.