Correlation between Interleukin-6 and Thrombin–Antithrombin III Complex Levels in Retinal Diseases

<p><i>Purpose</i>: This study aims to evaluate and correlate the levels of interleukin-6 (IL-6) and thrombin–antithrombin III complex (TAT) in the vitreous of patients with different vitreoretinal pathologies.</p> <p><i>Methods</i>: Vitreous samples were collected from 78 patients scheduled for pars plana vitrectomy at a tertiary medical center. Patients were divided by the underlying vitreoretinal pathophysiology, as follows: macular hole (MH)/epiretinal membrane (ERM) (<i>n</i> = 26); rhegmatogenous retinal detachment (RRD) (<i>n</i> = 32); and proliferative diabetic retinopathy (PDR) (<i>n</i> = 20). Levels of IL-6 and TAT were measured by enzyme-linked immunosorbent assay and compared among the groups.</p> <p><i>Results</i>: A significant difference was found in the vitreal IL-6 and TAT levels between the MH/ERM group and both the PDR and RRD groups (<i>P</i> < 0.001 for all). Diabetes was associated with higher IL-6 levels in the RRD group. Different relationships between the IL-6 and TAT levels were revealed in patients with different ocular pathologies.</p> <p><i>Conclusion</i>: Our results imply that variations in vitreal TAT level may be attributable not only to an inflammatory reaction or blood–retinal barrier breakdown, but also to intraocular tissue-dependent regulation of thrombin.