<prompt> Most common cause of bacterial peritonitis isPrimary or spontaneousPerforated viscusForeign bodyBiliary peritonitis  <response>: Peritonitis secondary to any bowel or other visceral pathology eg. perforation, appendicitis is termed as secondary peritonitis, E-Coli is the commonest organism causing this. Primary peritonitis - there is no documented infection, it;s monomicrobial, extraperitoneal postoperative leak after surgery for gallbladder, CBD, ERCP, duodenum, pyloroplasty Reference: SRB 5th edition page no.566,573 