A Case of Huge Granulomatous Appendicitis with Abscess Formation in the Appendiciceal Wall

Abstract

A 22-year-old man admitted for the right lower quadrant abdominal pain and 9.0×5.8×3.3cm tumor with peritoneal irritant signs was found in ultrasonography and computed tomography to have a massive lesion of the right iliac fossa. Under a diagnosis of acute appendicitis with abscess formation, we conducted laparotomy. The extreme swelling of the appendix suggested malignancy, so we conducted an ileocecal-resection. Microscopic findings of the resected specimen revealed included and cavity formation of the appendix wall, multinucleated giant cells, epitheloid granuloma, and a caseous necrosis, leading to a diagnosis of granulomatous appendicitis (GA). Serological tests for Yershinia Enterocolicia antibody were negative. GA was originally thought to be a form of Crohn.s disease, and to be uncommon, but it was reported 0.1 to 2.0% of appendectomy specimens have granulomatous change microscopically. Reported causes of GA are Crohn.s disease, infection, foreign bodies, and delayed or interval appendectomy. The most recent speculation involves yershinia species, but it is difficult to elucidate pathogenesis. In our case it was suggested that foreign body like a fish bone and consequence of the use of antibiotic drug as causes of GA.