peritonitis /per′itənī″tis/ [Gk, peri + teinein, to stretch, itis] , an inflammation of the peritoneum. It is produced by bacteria or irritating substances introduced into the abdominal cavity by a penetrating wound or perforation of an organ in the GI tract or the reproductive tract. Peritonitis is caused most commonly by rupture of the appendix but also occurs after perforations of intestinal diverticula, peptic ulcers, gangrenous gallbladders, gangrenous obstructions of the small bowel, or incarcerated hernias, as well as ruptures of the spleen, liver, ovarian cyst, or fallopian tube, especially in ectopic pregnancy. In some cases, peritonitis is secondary to the release of pancreatic enzymes, bile, or digestive juices of the upper GI tract, and there are reports of postoperative peritonitis caused by cornstarch used to powder surgical gloves. The bacteria most frequently identified as causative agents in peritonitis are Escherichia coli, Bacteroides, Fusobacterium, and anaerobic and aerobic streptococci. Pneumococci occasionally found in peritonitis in girls are thought to enter the abdominal cavity via the vagina and fallopian tubes. See also acute diffuse peritonitis, adhesive peritonitis. ▪ OBSERVATIONS: Characteristic signs and symptoms include abdominal distension, rigidity and pain, rebound tenderness, decreased or absent bowel sounds, nausea, vomiting, and tachycardia. The patient has chills and fever; breathes rapidly and shallowly; is anxious, dehydrated, and unable to defecate; and may vomit fecal material. Leukocytosis, an electrolyte imbalance, and hypovolemia are usually present, and shock and heart failure may ensue.
