Acute diverticulitis in patients under 40 years of age: radiologic diagnosis.

During a 4-year period, eight patients 40 years old or younger had surgically proved diverticulitis at our institution. None of these patients had connective-tissue diseases or were on medication (i.e., steroids) that would predispose them to diverticulosis. The presenting clinical symptoms in this group of patients were often misleading, and in only one of the eight cases was the correct clinical diagnosis made at the time of admission. Of the three diagnostic studies that were performed (barium enema, sonography, and CT), barium enema was the most accurate, yielding evidence for diverticulitis in six of seven cases. The degree and extent of diverticulosis in these patients was minimal compared with that in the older patients. CT showed abdominal abscesses in two patients; in one, a mistaken diagnosis of Crohn disease was made; in the other, diverticulitis was correctly identified. In the three patients in whom sonography was performed, the findings were negative for diverticulitis. Our experience suggests that the diagnosis of acute diverticulitis should be considered in patients with abdominal pain who are less than 40 years old.