Omental appendagitis is an inflammation of the pedunculated fatty fringes of the colonic serosa, sometimes confused with appendicitis or diverticulitis. We report the case of a diabetic and hypertensive subject who underwent a cholecystectomy and a left inguinal hernia, was referred for abdominal pain associated with a pseudo-surgical abdomen with a positive inflammatory assessment and an abdominal CT scan in favor of acute appendagititis, and improved with level 2 anti-inflammatory steroid and analgesic treatment. Acute appendagitis constitutes a rare emergency for which therapies and downstream monitoring are specific.