IL6 and complex regional pain syndrome: Consistent with the finding that TNF-alpha levels may change in some patients with disease duration, one of the other studies found increased TNF-alpha and IL-6 immunostaining on keratinocytes in affected skin (compared with the contralateral limb) to be more frequent in patients with acute than chronic CRPS.4 The opposing directional relationship between TNF-alpha and disease duration in the 2 studies may arise due to methodological differences (plasma vs skin biopsy) or the dissimilar subgroup focus (normal inflammatory profile/inflammatory profile vs acute/chronic).