Clinical diagnosis of primary epiploic appendagitis: differentiation from acute diverticulitis.

Background: Primary epiploic appendagitis (PEA) is an uncommon cause of abdominal pain that occurs either from appendageal torsion or spontaneous thrombosis of an appendageal draining vein. Primary epiploic appendagitis is frequently misdiagnosed as either appendicitis or diverticulitis, depending on its location.

Study: Clinical and radiologic characteristics of 8 patients with PEA were retrospectively reviewed and compared with 18 patients with acute diverticulitis.

Results: Patients with PEA presented with lower abdominal pain of recent onset that was localized to the left (seven cases) and right (one case) lower quadrants. Well-localized tenderness without peritoneal irritation sign was usually the only physical finding. Blood tests were not significant. In acute diverticulitis, the pain was more evenly distributed throughout the lower abdomen and findings like nausea, fever, and leukocytosis were more frequently associated than in PEA. Computed tomography findings, such as pedunculated oval fatty mass with streaky densities connected to the serosal surface of the adjacent colon, can lead to the diagnosis of PEA. Symptoms of PEA were resolved within 1 week (mean, 4.7 days) without surgery.

Conclusions: When patients with very localized lower abdominal pain and tenderness do not have associated symptoms or laboratory abnormalities, a high index of suspicion for PEA and early radiologic examinations are required.