Reflex Sympathetic Dystrophy

Reflex sympathetic dystrophy is a poorly understood condition of chronic pain, edema, and trophic changes developing in an area innervated by a partially damaged peripheral nerve. Classically, the pain occurs weeks after the injury and persists indefinitely. The syndrome is notoriously variable. Some authors prefer use of the term causalgia or complex regional pain syndrome. This extremely painful condition is thought to be mediated in part through the action of the sympathetic nervous system because some patients benefit from chemical or surgical sympathectomy. There is also evidence of a role for sensitization of the central nervous system in association with the primary partial peripheral denervation. Kemler et al. (1999) found a frequency of HLA-DQ1 (see 146880) of 69% in 52 unrelated Dutch patients with reflex sympathetic dystrophy in comparison to a frequency of 42% in a control group of 295 unrelated healthy individuals.