The most common mechanism of perforation in appendix is

Appendicular Perforation Immediate appendectomy has long been the recommended treatment for acute appendicitis because of the presumed risk of progression to rupture The overall rate of perforated appendicitis is 25.8% Children <5 years of age and patients >65 years of age have the highest rates of perforation (45 & 51% respectively) Risk factors for Appendicular Perforation Fecolith Diabetes mellitus Immunosuppression Extremes of age Pelvic appendix Previous abdominal surgery It has been suggested that delays in presentation are responsible for the majority of perforated Appendices Appendiceal rupture occurs most frequently distal to the point of luminal obstruction along the anti mesenteric border of the appendix Rupture should be suspected in the presence of fever with a temperature of < 39% (102degF) and a WBC count of >18000 cells/mm3 MC bacteria isolated in perforated appendicitis : Bacteroides fragilis (80%) > E.coli (77%) Ref: Sabiston 20th edition Pgno : 1297