Purpose: To determine the levels of interleukin 8 (IL-8) in the vitreous of patients with proliferative diabetic retinopathy (PDR).
Design: Observational case-control study.
Methods: Vitreous fluid samples were obtained by vitreoretinal surgery from 71 eyes of patients with diabetes mellitus type 2 with PDR and from 17 eyes of nondiabetic patients with a macular hole. PDR was classified as active and inactive and subdivided according to the extent of large-vessel gliotic obliteration. The cytokine levels were measured by cytometric bead array method.
Results: The vitreous levels of IL-8 were significantly higher in patients with PDR in comparison with the control subjects (P < .001) and in patients with higher extent of large vessel gliotic obliteration (P < .001). A vitreous level of IL-8 was not associated with the presence of active PDR.
Conclusion: Increased levels of IL-8 in PDR were associated with a higher extent of large-vessel gliotic obliteration.