Symptoms of Peritoneal Abscess
Peritoneal abscesses present with abdominal pain, tenderness, fever, nausea, and vomiting as the most common symptoms, and diagnosis should be confirmed with CT imaging, which is the modality of choice for adults not undergoing immediate laparotomy. 1
Clinical Presentation
Common Symptoms
- Abdominal pain and tenderness (often localized to the area of the abscess)
- Fever and chills
- Nausea and vomiting
- Altered mental status (especially in immunocompromised patients)
- Anorexia and weight loss
Physical Examination Findings
- Localized abdominal tenderness
- Guarding and rigidity
- Palpable abdominal mass (in some cases)
- Decreased or absent bowel sounds
- Signs of systemic inflammatory response (tachycardia, tachypnea)
Laboratory Findings
- Leukocytosis with left shift
- Elevated inflammatory markers (ESR, CRP)
- Blood cultures positive in up to 28% of cases 2
- Abnormal liver function tests (if abscess is near liver)
Special Considerations
Atypical Presentations
- Immunocompromised patients may present with subtle or atypical symptoms 1
- Patients with spinal cord injuries or altered mental status may have minimal abdominal complaints despite significant infection 1
- Post-operative peritoneal abscesses often have atypical clinical presentations which may delay diagnosis 1
High-Risk Populations
- Post-surgical patients (especially after gastrointestinal surgery)
- Patients with recent peritonitis
- Immunocompromised individuals
- Diabetic patients
- Patients on peritoneal dialysis 3
Diagnostic Approach
Imaging
- CT scan is the imaging modality of choice for adults with suspected intra-abdominal infection 1
- Ultrasonography may be useful for superficial abscesses or when CT is unavailable 1
- Plain radiographs have limited utility but may show free air or obstruction
Differential Diagnosis
- Primary peritonitis (especially in cirrhotic patients)
- Secondary peritonitis from perforated viscus
- Tertiary (persistent) peritonitis
- Inflammatory bowel disease flare
- Pancreatitis
- Mesenteric ischemia
Complications
- Sepsis and septic shock
- Multiple organ dysfunction syndrome
- Extension of infection to adjacent structures
- Fistula formation
- Adhesions and bowel obstruction
Red Flags Requiring Urgent Intervention
- Signs of septic shock (hypotension, altered mental status)
- Diffuse peritonitis
- Respiratory distress
- Immunocompromised status with signs of infection
- Failure to improve with initial management
Early diagnosis and appropriate treatment of peritoneal abscesses are crucial for improving outcomes, as mortality increases significantly when diagnosis and treatment are delayed beyond 4 days 2. The clinical presentation can be variable and nonspecific, requiring a high index of suspicion, particularly in post-surgical patients where atypical presentation may lead to delayed diagnosis 1.