[Are systemic diseases of infectious origin?].

Defined as diffuse inflammatory disorders, theoretically of unknown origin, systemic diseases would thus not be of infectious origin. Nevertheless, a series of examples shows that it is possible for some, and probable for others, that a parasitic, bacterial or especially viral infection would be a triggering or maintaining factor. In addition, better means of investigation have already and will certainly lead to more precise study of this interaction. New pathophysiological mechanisms are predicted and sometimes already shown. The results have already influenced therapy. It can therefore be concluded that at least some diseases considered to by systemic are probably of infectious origin.