Peritonitis, bacterial primary

Peritonitis may be classified as primary, secondary, or tertiary. Primary peritonitis, also called spontaneous bacterial peritonitis, is an infection of the peritoneal cavity without an evident source of bacteria from the abdomen.1,2 In secondary peritonitis, a focal disease process is evident within the abdomen. Secondary peritonitis may involve perforation of the gastrointestinal (GI) tract (possibly because of ulceration, ischemia, or obstruction), postoperative peritonitis, or posttraumatic peritonitis (e.g., blunt or penetrating trauma). Tertiary peritonitis occurs in critically ill patients and is infection that persists or recurs at least 48 hours after apparently adequate management of primary or secondary peritonitis. 

An abscess occurs if peritoneal contamination is localized but bacterial elimination is incomplete. The location of the abscess often is related to the site of primary disease. For example, abscesses resulting from appendicitis tend to appear in the right lower quadrant or the pelvis those resulting from diverticulitis tend to appear in the left lower quadrant or pelvis. A mature abscess may have a fibrinous capsule that isolates bacteria and the liquid core from antimicrobials and immunologic defenses. 

Primary peritonitis is treated with antimicrobials and rarely requires drainage. Secondary peritonitis requires surgical removal of the inflamed or gangrenous tissue to prevent further bacterial contamination. If the surgical procedure is sub-optimal, attempts are made to provide drainage of the infected or gangrenous structures. 

Primary bacterial peritonitis is often caused by a single organism. In children, the pathogen is usually Group A Streptococcus, Streptococcus... 

Intraabdominal infections have a wide spectrum of clinical features often depending on the specific disease process, the location and the magnitude of bacterial contamination, and concurrent host factors. Patients with primary and secondary peritonitis present quite differently (Table 42-3). 

Intraabdominal infections have a wide spectrum of clinical features often depending on the specific disease process, the location and the magnitude of bacterial contamination, and concurrent host factors. Patients with primary and secondary peritonitis present quite differently (Table 42-3). If peritonitis continues untreated, the patient may experience hypovolemic shock from fluid loss into the peritoneum, bowel wall, and lumen. This may be accompanied by generalized sepsis. Intraabdominal abscess may pose a diagnostic challenge as the symptoms are neither specific nor dramatic. 

Dann PH, Amodio JB, Rivera R et al (2005) Primary bacterial peritonitis in otherwise healthy children imaging findings. Pediatr Radiol 35 198-201 Dasgupta R, Langer JC (2004) Hirschsprung disease. Curr Probl Surg 41 942-988... 

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