Vitreous level of tumor necrosis factor alpha in patients with macular edema secondary to retinal vein occlusion

Abstract

PurposeRetinal vein occlusion (RVO) induces ischemia that triggers the release of inflammatory cytokines, including tumor necrosis factor alpha (TNF- α). We aimed at measuring TNF- α level in vitreous samples of treatment naïve RVO patients.Material and Methodsthis is a case control study. The study was conducted on 45 eyes (20 eyes with treatment naïve RVO associated with macular edema & 25 eyes of patients undergoing cataract surgery as control). Vitreous samples were collected using 25 gauge needle connected to 1 milliliters (ml) syringe and the level of TNF- α was assessed using Enzyme-linked Immunosorbent Assay (ELISA) Kits.ResultsThe mean age of RVO cases was 51.50 ± 12.86 years while controls was 55.76 ± 6.88 years (P value =0.192). Vitreous level of TNF-α was statistically significant higher in RVO patients [4.92 ± 0.74 picograms (pg)/ ml] than control [3.54 ± 0.60 pg/ml]; p value < 0.001. Vitreous TNF-α level in ischemic and non-ischemic RVO subgroups was 4.94 ± 0.69 pg/ml and 4.89 ± 0.89 pg/ml respectively that wasn't statistically significant (p value = 0.885) and its level in branch and central RVO subgroups was 5.02 ± 0.79 pg/ml and 4.84 ± 0.73pg/ml respectively not statistically significant (p value = 0.592).ConclusionsTNF-α level is increased in vitreous of RVO associated macular edema patients, thus, it may be involved in its pathogenesis and Anti-TNF-α might be used as treatment targets in the future.

Keywords: ELISA; macular edema; retinal vein occlusion; tumor necrosis factor- α; vitreous tapping.