The ocular surface in cystic fibrosis.

Seventeen patients with cystic fibrosis and 17 age-, race-, and sex-matched controls were examined under standardized conditions. Testing included slit-lamp biomicroscopy, fluorescein staining, rose bengal staining, Schirmer's basic tear test, tear film break-up time, tear pH, tear lysozyme, tear protein, lid and conjunctival cultures, and conjunctival impression cytology. Cystic fibrosis patients showed a statistically significant increase in the incidence of fluorescein staining and clinical blepharitis, as well as significantly decreased Schirmer testing and tear lysozyme. Ocular surface abnormalities in these patients may be attributable to aqueous and lipid tear film deficiencies. Cystic fibrosis patients showed normal conjunctival epithelial cell morphology, grew no pathogenic organisms, and had a decreased incidence of conjunctival bacterial colonization.