SINCE the description of periarteritis nodosa by von Rokitansky1 in 1852 and by Kussmaul and Maier2 in 1865, numerous reports have appeared in the literature. Dickson3 and subsequent observers favored the designation of polyarteritis nodosa, since the inflammatory reaction is not confined to the adventitial or periadventitial tissues. This term is probably more adequate in describing the morphologic characteristics of the disease, although since the etiologic factors are still under consideration, primary arteritis in the sense implied by Karsner4 of an arteritis in which the infective organisms are not demonstrated warrants consideration.
The cause of this disease has been and is a much debated point, although some are of the opinion that a filtrable virus is the causative agent.5 Syphilis at one time had been suspected but this view has been entirely discarded. Spiro6 expressed the opinion that it was a form of postinfectional