Peritoneal abscess describes the formation of an infected fluid collection encapsulated by fibrinous exudate, omentum, and/or adjacent visceral organs. The overwhelming majority of abscesses occurs subsequent to Secondary Peritonitis. Approximately half of patients develop a simple abscess without loculation, whereas the other half of patients develop complex abscesses secondary to fibrinous septation and organization of the abscess material. Abscess formation occurs most frequently in the subhepatic area, the pelvis, and the paracolic gutters, but it may also occur in the perisplenic area, the lesser sac, and between small bowel loops and their mesentery.
Drainage of pus is mandatory and is the first line of defense against progressive sepsis. Percutaneous CT-guided catheter drainage has become the standard treatment for most intra-abdominal abscesses. It avoids possibly difficult laparotomy, prevents the possibility of wound complications from open surgery, and may reduce the length of hospitalization. It also obviates the possibility of contamination of other areas within the peritoneal cavity. CT-guided drainage delineates the abscess cavity and may provide safe access for percutaneous drainage.
Peritonitis is defined as inflammation of the serosal membrane that lines the abdominal cavity and the organs contained therein. Peritonitis is often caused by introduction of an infection into the otherwise sterile peritoneal environment through perforation of the bowel, such as a ruptured appendix or colonic diverticulum. The disease may also be caused by introduction of a chemically irritating material, such as gastric acid from a perforated ulcer or bile from a perforated gall bladder or a lacerated liver. In women, there may be a pelvic localized peritonitis secondary to infections originated at uterus and Fallopian tubes..
Peritoneal infections are classified as primary (ie, spontaneous), secondary (ie, related to a pathologic process in a visceral organ), or tertiary (ie, persistent or recurrent infection after adequate initial therapy).
The most common etiology of primary peritonitis is spontaneous bacterial peritonitis (SBP) due to chronic liver disease. Approximately 10-30% of all patients with liver cirrhosis who have ascites develop bacterial peritonitis over time.
The common etiologic entities of secondary peritonitis (SP) include perforated appendicitis; perforated gastric and duodenal ulcer disease; perforated (sigmoid) colon caused by diverticulitis, volvulus, or cancer; and strangulation of the small bowel
Spontaneous bacterial peritonitis (SBP) is an acute bacterial infection of ascitic fluid. Frequently the infectious agent can not be identified, but contamination of dialysate can cause the condition among those receiving peritoneal dialysis (PD). SBP occurs in both children and adults and is a well-known and ominous complication in patients with cirrhosis.