Most common cause of bacterial peritonitis is
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
Primary or spontaneous
Perforated viscus
Foreign body
Biliary peritonitis
G.I.T