[Chronic fatigue syndrome].

Enduring and disabling fatigue that cannot be explained by a known disease is the main characteristic of chronic fatigue syndrome. Several definitions do exist, and classification approaches vary regarding supplementary symptoms, time course, and by implicit concepts of aetiology. CFS can be considered as a functional somatic syndrome, e. g. supported by the high rates of comorbid bodily complaints and syndromes that lack clear medical explanation. Accordingly the diagnostic process should not be limited to the thorough physical examination, but also address additional somatic complaints, psychosocial factors (specifically subjective illness beliefs), and impairments. Recently German medical and psychological societies provided treatment guidelines for functional somatic syndromes. Cognitive behavioural therapy and graded activity are evidence based treatment methods for CFS. © Georg Thieme Verlag KG Stuttgart · New York.