**3.2 Chronic WAD**

We identified two studies (**Table 2**) using the same material concerning patients with chronic WAD (Gerdle et al., 2008b; Gerdle et al., 2008c), and 5-HT and IL-6 were significantly higher in WAD than in HC. No differences were found in the concentrations of investigated metabolites, potassium, glutamate, BKN, or kallidin compared with healthy controls.
