A case report in this issue of The Journal, page 653, by Alkalay and co-workers calls attention to a syndrome that seems to be in the process of being differentiated from the pyrexias of unknown origin. In 1948 Reimann1 grouped together under the term periodic disease a series of patients with somewhat diverse symptomatology, characterized by periodic recurrence of symptoms over a long period of time and without known cause. The findings most frequently noted were recurring fever, abdominal pain, and joint pain. Similar cases have been described by others under such terms as benign paroxysmal peritonitis, periodic peritonitis, periodic arthralgia, periodic abdominalgia, and familial Mediterranean fever. Heller and associates2 proposed the following diagnostic criteria: (1) attacks of fever, usually of short duration, recurring at varying intervals over the course of many years; (2) painful manifestations usually but not always with each attack located in abdomen, chest, joints,