Cytokine Profiles of Tear Fluid From Patients With Pediatric Lacrimal Duct Obstruction.

Purpose: This study evaluated the cytokine levels in unilateral tear samples from both sides in patients with pediatric lacrimal duct obstruction. Methods: Fifteen cases of unilateral lacrimal duct obstruction (mean, 26.9 ± 28.7 months old) were enrolled in this study. Tear samples were collected separately from the obstructed side and the intact side in each case before surgery, which was performed under general anesthesia or sedation. The levels of IL-2, IL-4, IL-6, IL-10, TNF, IFN-γ, and IL-17A then were measured in each tear sample. A receiver operating characteristic (ROC) curve was constructed for the IL-6 levels in the tears. We also measured the postoperative tear fluid levels of IL-6 in those cases from which tear fluid samples could be collected after the surgery. Results: Only the IL-6 concentration was significantly higher on the lacrimal duct-obstructed sides, compared to the control sides (P < 0.001). An ROC curve analysis for the IL-6 levels in tears showed a high value for discriminating the lacrimal duct-obstructed side from the control side (area under the ROC curve [AUC], 0.99; 95% confidence interval [CI], 0.968-1). Significant decrease of the tear fluid IL-6 levels was observed in the seven cases from which tear fluid samples also could be collected after the surgery (P = 0.016). Conclusions: The IL-6 level in tear fluid was significantly higher on the sides with lacrimal duct obstruction, compared to the control sides, and could be a biomarker for pediatric lacrimal duct obstruction.