Gong X, Ren Y, Fang X, et al. - This prospective consecutive randomized clinical study was undertaken to determine if substance P (SP), a nociceptive tachykinin which regulates the immune-inflammatory reactions including monocyte chemoattractant protein 1 (MCP-1) production, is involved in sympathetic inflammatory responses in the contralateral eye in patients with or without type 2 diabetes. Participants in the study were 51 cataract patients (22 with diabetes and 29 without). Productions of SP and MCP-1 elevated in the AH of the contralateral eye after the first-eye cataract surgery in diabetic patients, suggesting that SP and MCP-1 were involved in the sympathetic inflammatory responses. After cataract surgery, diabetic patients are vulnerable to noninfectious inflammation and feel more discomfort in second-eye phacoemulsification.