Vitreous levels of interleukine-8 and monocyte chemoattractant protein-1 in macular oedema with branch retinal vein occlusion.

ABSTRACT

PURPOSE: To investigate whether interleukine-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) are related with macular oedema in patients with branch retinal vein occlusions (BRVOs). DESIGN: Retrospective case-control study. PARTICIPANTS: Nineteen patients who had macular oedema due to BRVO and nine patients with non-ischaemic ocular diseases (control group). METHODS: Macular oedema was examined by optical coherence tomography. Both venous blood and vitreous samples were obtained at the time of vitreoretinal surgery. IL-8 and MCP-1 levels in vitreous fluid and plasma were determined with enzyme-linked immunosorbent assay kits. Variables were compared with the Mann-Whitney U-test, Wilcoxon's signed-ranked test, and the chi2-test, when appropriate. To examine correlations, Spearman's rank-order correlation coefficients were calculated. Statistical significance was set at P<0.05. RESULTS: The vitreous fluid levels of IL-8 (median 63.5 pg/ml) and MCP-1 (median 1522.4 pg/ml) were significantly higher in the patients with BRVO than in the control group (median 5.1 and 746.5 pg/ml respectively; P<0.001 and <0.001 respectively). Vitreous IL-8 and MCP-1 were significantly correlated in patients with BRVO (P=0.009). CONCLUSIONS: Both IL-8 and MCP-1 were elevated in the vitreous fluid of patients with BRVO and macular oedema. Both chemokines may contribute to the pathogenesis of macular oedema in patients with BRVO.