Effect of Histocompatibility Y Antigen Matching on Graft Survival in Primary Penetrating Keratoplasty.

Purpose: To investigate the influence of histocompatibility Y (H-Y) antigen matching on corneal graft survival in primary penetrating keratoplasty (PK). Methods: Medical records of patients who underwent primary PK at Seoul National University Bundang Hospital between June 2005 and October 2015 were retrospectively analyzed. The eyes were classified into 2 groups: H-Y-compatible (115 eyes) and H-Y-incompatible (23 eyes). The H-Y-compatible group included donor/recipient combinations of male/male (57 eyes), female/male (44 eyes), and female/female (14 eyes). The H-Y-incompatible group included the male/female (23 eyes) combination alone. A subgroup analysis of low-and high-risk patients according to preoperative diagnoses was also performed. Survival analysis was conducted using the Kaplan-Meier method; differences between groups were assessed with a log-rank test. Results: A total of 138 eyes from 136 patients (age: 58 +/- 18 years) were enrolled. Rejection-free graft survival and graft survival were not significantly different between H-Y-compatible and H-Y-incompatible groups (chi(2) = 0.4, P = 0.548; chi(2) = 1.9; P = 0.17, respectively). Preoperative diagnoses of high-risk cases included those with corneal perforation or thinning (8.7%) and infectious keratitis (7.2%). Low-risk cases included corneal opacity (50.0%), bullous keratopathy (25.4%), keratoconus (5.8%), and corneal dystrophy (2.9%). In the high-risk group, rejection-free graft survival rate was significantly higher in the H-Y-compatible group (chi(2) = 3.9, P = 0.049). Conclusions: H-Y antigen matching does not influence graft rejection and failure in cases of primary PK. However, matching the H-Y antigen could help reduce graft rejection, especially in preoperatively high-risk patients.