PURPOSE: Giant papillary conjunctivitis in patients wearing contact lenses occurs after intolerance and/or allergy to contact lenses. Eotaxin is a CC chemokine with a potent and specific chemotactic effect for eosinophils, which are involved in allergies. The purpose of this study is to measure the eotaxin levels in tears of patients wearing contact lenses and in normal subjects. Eotaxin levels were also correlated with the grade of giant papillary conjunctivitis. METHODS: Around 10 microL of tears were collected with glass capillaries in 16 patients wearing contact lenses and in 10 normal volunteers. Giant papillary conjunctivitis was graded from 0 to 4 by reference to standard slit-lamp photographs of the superior tarsal conjunctiva. Eotaxin concentration in tears was measured by ELISA using mouse anti-human eotaxin monoclonal antibodies. For the statistical analysis of the results, the paired Wilcoxon/Kruskal-Wallis test was used. RESULTS: The mean concentration of eotaxin was 2698+/-233 (SEM) pg/mL in patients wearing contact lenses and 1498+/-139 pg/mL in normal subjects. The difference was statistically significant (P=0.0004). The mean score of papilla grade was 1.75+/-0.19 in patients wearing contact lenses and 0.2+/-0.13 in normal subjects (P<0.0001). Papilla grade could be correlated to the eotaxin level in tears (R2=0.6562 and P<0.0001). CONCLUSION: An increase of eotaxin levels in tears was measured in patients wearing contact lenses. Eotaxin levels correlated with the severity of giant papillary conjunctivitis. These data suggest that eotaxin could play a role in papilla formation.