Other studies have shown increased levels of IL-8 pro-inflammatory cytokine in blood and also Cerebrospinal fluid (CSF) of the patients with chronic pain [21], elevated levels of IL-6, IL-1β, and TNF-α in CSF of the patients with complex regional pain syndrome [22] and prominent levels TNF-α in Schwann cells of the patients with painful neuropathies [23]. The gene discussed is TNF; the disease is complex regional pain syndrome.