Associatıon of systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) with graft survival in regraft cases after penetrating keratoplasty.

PURPOSE: To evaluate whether preoperative systemic immune-inflammatory indices are associated with subsequent regraft requirement due to late endothelial failure following penetrating keratoplasty (PK). METHODS: This retrospective study reviewed 1,738 PK cases performed in a tertiary eye center. Eyes that later underwent regraft due to late endothelial failure (n=51) were compared with PK recipients maintaining long-term graft clarity (n=50). Preoperative complete blood counts obtained prior to the primary PK were used to calculate neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation Index (SII) and Systemic Inflammation Response Index (SIRI). Donor characteristics, preservation intervals, surgical parameters, and glaucoma-related variables were recorded. Multivariable logistic regression and receiver operating characteristic (ROC) analyses were performed to identify factors associated with regraft risk. RESULTS: Neutrophil counts, NLR, SII and SIRI were significantly higher in the regraft cohort, whereas lymphocyte, monocyte, platelet counts, and PLR did not differ between groups. SII and SIRI demonstrated modest discriminative ability for regraft (AUC 0.649 and 0.642 respectively). In multivariable analyses both SII (OR 1.002 per unit increase, p=0.037) and SIRI (OR 2.657 per unit increase, p=0.023) remained independently associated with regraft after adjustment for donor age, preservation intervals, graft size, and glaucoma-related factors. Donor age and the number of antiglaucoma medications were also independently associated with regraft risk. Notably, shorter preservation intervals in the regraft cohort did not translate into improved outcomes. CONCLUSIONS: Elevated preoperative SII and SIRI values were associated with subsequent regraft requirement due to late endothelial failure after PK. Although their discriminative performance was modest, these findings suggest that systemic immune-inflammatory status may contribute to long-term graft outcomes and may provide supportive information within a multifactorial preoperative risk assessment framework.Hemogram-derived indices may provide supportive information as adjunctive markers within preoperative risk assessment frameworks in corneal transplantation.