[Right colon diverticulitis]

Diverticulitis involving the right colon is uncommon in the Occident; only one case for every 300 cases of appendicitis occurs in Western countries compared to a ratio of 1/40-1/180 in Asia. The preferential localization of diverticula in the right colon among Asiatics is probably due to genetic factors. In Asia as in the West, a right colon diverticulum is more likely to cause hemorrhage than diverticulitis. The peak age of symptoms is 40-45 years and the sex ratio is 1:1. The patient most commonly presents with symptoms suggestive of acute appendicitis, acute localized peritonitis, or, more rarely, a psoas abscess. Clinical exam reveals an inflammatory mass in the right lower quadrant in 30% of cases; diffuse peritonitis, large abscesses, and fistulae are rare. Helical CT scan is the best tool for establishing the diagnosis and also helps to rule out other possible etiologies in the differential diagnosis-particularly a perforated right colon cancer. In noncomplicated cases with convincing evidence for the diagnosis by CT scan, a conservative (non-surgical) treatment with antibiotics is possible; a later stage colonoscopy will rule out other colonic lesions. More commonly, the correct diagnosis is only made after embarking on an appendectomy via a McBurney incision; the surgical strategy thereafter depends on the level of suspicion regarding the diagnosis and the extent and complexity of the diverticulitis. Therapeutic options may be conservative (appendectomy), limited (diverticulectomy, or extensive (ileocecal resection or right hemicolectomy). For complicated disease (abscess, localized perforation), an aggressive surgical approach is warranted. Surgical strategies need to be validated, particularly in the light of the increasing use of the laparoscopic approach for suspected appendicitis.