ESSENTIAL FEATURES
• Bacterial peritonitis is a suppurative response of the peritoneal lining to direct bacterial contamination
• Clinical manifestations include:
–Fever and chills
–Tachycardia
–Acute abdomen
–Free air on plain films
EPIDEMIOLOGY
• Primary bacterial peritonitis is caused mainly by hematogenous spread or transluminal invasion in patients with advanced liver disease and reduced ascitic fluid protein concentration
• Surgical causes are classified as secondary bacterial peritonitis resulting from bacterial contamination originating from within the viscera
• Secondary bacterial peritonitis most commonly follows disruption of a hollow viscus
• Most common etiology in young patients is perforated appendicitis
• Most common etiology in elderly patients is complicated diverticulitis or perforated peptic ulcer
CLINICAL FINDINGS
SYMPTOMS AND SIGNS
• Fever and chills
• Tachycardia
• Oliguria
• Severe abdominal pain with rebound tenderness, guarding, and rigidity (“acute abdomen”)
• Diminished bowel sounds
• Physical signs of peritonitis may be subtle in the very young or old and in patients who are immunosuppressed
LABORATORY FINDINGS
• Leukocytosis
• Abnormal liver profile or renal function test
• Mild elevation in amylase
• Elevated ESR and C-reactive protein
• Bacteremia
IMAGING FINDINGS
• Abdominal x-ray: Demonstrates free air and ileus pattern and may suggest the primary etiology
• Water soluble contrast study: Demonstrates the location of the perforated viscus
• Abdominal pelvic CT scan with IV and PO contrast: Best exam for characterizing source of bacterial peritonitis, although an operation should not be delayed to obtain this test in patients with an acute abdomen
DIAGNOSTIC CONSIDERATIONS
• Primary bacterial peritonitis
• Etiology of secondary bacterial peritonitis:
–Appendicitis
–Perforated gastroduodenal ulcers
–Diverticulitis
–Gangrenous cholecystitis
–Acute salpingitis
–Nonvascular small bowel perforation
–Large bowel perforation
–Mesenteric ischemia
–Acute necrotizing pancreatitis
–Postoperative complications
–Others
• Familial Mediterranean fever
RULE OUT
• Primary bacterial peritonitis in patients with advanced liver disease (high operative mortality)
• Nonoperative causes of peritonitis
–Pancreatitis
–Pyelonephritis
–Acute salpingitis
WORK-UP
• Thorough history and physical exam
• CBC
• Basic chemistries
• Amylase and lipase
• UA
• Liver profile
• Coagulation studies
• Abdominal x-rays
WHEN TO admit
• All patients with bacterial peritonitis should be admitted for appropriate surgical and medical management
WHEN TO refer
• Primary bacterial peritonitis is ideally cared for nonoperatively by gastroenterologists
• Secondary bacterial peritonitis should be managed by a general surgeon
TREATMENT AND MANAGEMENT
• Resuscitation with IV fluids and electrolyte replacement
• Operative control of the abdominal sepsis
• Systemic antibiotics
• Cardiorespiratory ICU support as indicated
SURGERY
Indications
• Operative goal is to correct the underlying cause of abdominal sepsis:
–Perforated viscus
–Ruptured appendix
–Infected necrotizing pancreatitis
–Gangrenous cholecystitis
–Abscess drainage
MEDICATIONS
• Systemic empiric antibiotics that cover aerobic and anaerobic enteric organisms
• Directed antibiotic therapy based on operative cultures
TREATMENT MONITORING
• Good urinary output
• Resolution of tachycardia
• Amelioration of fever and leukocytosis
• Resolution of ileus
Complications omplications
• Uncontrolled abdominal sepsis and death
• Abscess formation
• Deep wound infections
• Anastomotic dehiscence
• Fistula formation
Prognosis
• Overall mortality for generalized peritonitis is 40%
• Factors contributing to mortality include:
–Type/duration of underlying disease
–Associated comorbidities
–Reduced cardiac status
–Low preoperative albumin
RESOURCES
REFERENCES
• Kim S et al: The perihepatic space: comprehensive anatomy and CT features of pathologic conditions. Radiographics 2007;27:129.
