Anomalies endocriniennes au cours de la fibromyalgie et du syndrome de fatigue chronique

Fibromyalgia is a syndrome characterized by chronic widespread pain and allodynia, a heightened and painful response to pressure, without biological detectable abnormalities. Fibromyalgia is frequently associated with debilitating fatigue, sleep disturbance, joint stiffness, difficulty with swallowing, bowel and bladder abnormalities, numbness and tingling; and cognitive dysfunction. Fibromyalgia is frequently comorbid with psychiatric conditions such as depression and anxiety and stress-related disorders such as posttraumatic stress disorder. It has been postulated that fibromyalgia can be the consequence of a chronic stress mediated mainly through the hypothalamo-pituitary-adrenal axis and the sympathetic nervous system. Hormonal systems are grossly normal and circadian rythms are unaltered. Despite some arguments in favour of a CRH neurons hyperactivity, these results are not able to consolide a particular physiopathological mechanism and to argument for a new therapeutic approach. Many of the hormonal abnormalities may be the consequence of psychological and stress disturbances. Chronic fatigue syndrome is the most common name given to a variably debilitating disorder defined by persistent fatigue unrelated to exertion, not substantially relieved by rest and accompanied by the presence of other specific symptoms for a minimum of six months. It is frequently associated with psychosocial factors, such as depression, sleep disorder, anxiety, and coping style, which suggest that dysregulation of the body's stress systems may serve as an underlying mechanism in the maintenance of chronic fatigue. Some endocrine factors may contribute to chronic fatigue syndrome. In general, hypoactivity of the hypothalamic-pituitary-adrenal axis, autonomic nervous system alterations characterized by sympathetic overactivity and low vagal tone, as well as immune abnormalities, secondary to severe and/or chronic stress, may contribute to the expression of chronic fatigue.