[Severe chronic pain with allodynia in Parkinson's disease: a case report]

We report a 61-year-old man with Parkinson's disease, who had a 3-year history of severe chronic pain with allodynia in the lower extremities prior to motor symptoms. He always had tingling pain around the ankles, and tactile sensation induced severe burning pain expanding to the toes and thighs, so his pain was considered to be allodynia. Pain and motor symptoms were ameliorated by L-dopa therapy and exacerbated by withdrawal of L-dopa. Pain is known to occur in Parkinson's disease, but severe pain rarely occurs. To our knowledge, allodynia, which is usually recognized in causalgia or reflex sympathetic dystrophy, has never been reported in Parkinson's disease. Patients with Parkinson's disease may complain severe causalgia-like pain as an initial symptom.