TNF and Behcet disease: It has been shown that serum levels of neutrophil-mediated proinflammatory cytokines tumor necrosis factor (TNF), interleukin 1 beta (IL-1β) and IL-8 are elevated during acute exacerbations.9 Furthermore, BD patients have exhibited elevated serum levels of homocysteine (Hcy),10 which has been proposed to play an important role in uveal inflammation by increasing nitric oxide (NO) synthesis in endothelial cells.