Pathogenic mechanisms of fibromyalgia.

The symptomatology characterizing fibromyalgia comprises three systems: the musculoskeletal system with widespread muscular pain, neuroendocrine disorders, and psychological distress including anxiety and depression. Fibromyalgia is predominantly found in middle aged women. Though the most prominent symptom of fibromyalgia is pain in defined regions of the locomotor system, the numerous other somatoform and psychological disorders suppose a common primary disturbance which is considered to originate within higher levels of the central nervous system. Studies of the entire endocrine profile of fibromyalgia patients support the hypothesis that an elevated activity of corticotropin releasing hormone (CRH) neurons determines not only many symptoms of fibromyalgia but may also cause alterations observed in the hormonal axes. Hypothalamic CRH neurons thus may play a key role not only in resetting the various endocrine loops but possibly also nociceptive and psychological mechanisms as well