The occurrence of permanent diabetes mellitus following attacks of acute and recurrent pancreatitis has been well established* Transient hyperglycemia and glycosuria have been noted frequently during acute attacks,3and in some instances patients with fulminating disease have died in diabetic coma.† Scant attention has been devoted, however, to the converse development of acute pancreatitis in patients known to have preexisting diabetes mellitus. Recently, we observed the occurrence of acute pancreatitis in three hospitalized patients with previously known diabetes. This prompted a review of the hospital records from 1936 to 1954 of all patients in whom a final diagnosis of acute pancreatitis had been made on the basis of clinical and/or autopsy criteria. Excluded from consideration were children, cases following abdominal surgery, and instances of chronic pancreatitis. Among 103 hospitalized patients with acute pancreatitis, 5 additional instances of its association with preexisting diabetes mellitus were encountered.‡ Eight patients, therefore, are