[Anorexia nervosa, a functional disorder between].

Anorexia nervosa (AN) is a functional eating disorder with a multifactorial origin without an underlying somatic disease. Two types of AN should be distinguished, pure restrictive AN and AN-boulimia with purging, most often among young females. AN is mainly a psychological disease, but it leads quite early to various somatic complications. Weight loss may be dramatic and different deficiencies then occur. Besides anorexia, aberrant behaviours may be present, which may be associated with severe complications. Management should be pluridisciplinary, yet no strategy has proved clear superiority. In cases with profound severity, either psychological/psychiatric or somatic, a hospitalization in a specialized unit becomes essential. The outcome remains uncertain and the final prognosis remains reserved in most cases.