What are the symptoms of Spontaneous Bacterial Peritonitis (SBP)?

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Symptoms of Spontaneous Bacterial Peritonitis (SBP)

Up to one-third of patients with spontaneous bacterial peritonitis (SBP) may be entirely asymptomatic or present only with worsening of liver function or hepatic encephalopathy. 1

Common Clinical Presentations

SBP presents with a wide spectrum of symptoms ranging from asymptomatic to severe systemic inflammation:

Cardinal Symptoms

  • Abdominal pain
  • Abdominal tenderness
  • Fever (or hypothermia in some cases)
  • Chills
  • Worsening ascites 1, 2

Other Common Manifestations

  • Altered mental status/worsening hepatic encephalopathy
  • Vomiting
  • Diarrhea
  • Ileus
  • Tachycardia
  • Tachypnea
  • Unexplained deterioration in clinical condition
  • Acute kidney injury 1, 2

High-Risk Scenarios

SBP should be strongly suspected in any patient with cirrhosis and ascites who presents with:

  • New-onset fever
  • Abdominal pain or tenderness
  • Unexplained clinical deterioration
  • Worsening encephalopathy
  • Acute kidney injury
  • Gastrointestinal bleeding 1

Diagnostic Approach

The diagnosis of SBP requires a high index of suspicion, as clinical symptoms may be subtle or absent. Diagnostic paracentesis should be performed immediately in all patients with cirrhosis and ascites who:

  • Are admitted to the hospital emergently for any reason
  • Develop signs of infection
  • Show worsening liver or renal function
  • Present with hepatic encephalopathy
  • Have gastrointestinal bleeding 1

The diagnosis is confirmed by an ascitic fluid neutrophil count >250/mm³ in the absence of an intra-abdominal surgically treatable source of infection 1.

Clinical Pitfalls to Avoid

  1. Delayed diagnosis: Each hour of delay in diagnosis is associated with a 3.3% increase in mortality. Do not wait for culture results to initiate treatment 1.

  2. Missing asymptomatic cases: Remember that up to one-third of patients may be asymptomatic or present with only subtle signs like worsening encephalopathy 1, 2.

  3. Overlooking SBP in patients with GI bleeding: All cirrhotic patients with gastrointestinal bleeding should undergo diagnostic paracentesis 1.

  4. Withholding paracentesis due to coagulopathy concerns: Despite abnormal coagulation panels in many cirrhotic patients, routine transfusion before paracentesis is not recommended 2.

  5. Failing to differentiate from secondary peritonitis: SBP is typically monobacterial with neutrophil count >250/mm³ but <1000/mm³, while secondary peritonitis is often polymicrobial with neutrophil count >1000/mm³ 1.

Early recognition of symptoms and prompt diagnostic paracentesis are critical for improving outcomes in patients with SBP, as mortality without prompt treatment can be as high as 20-40% 1.

References

Guideline

Spontaneous Bacterial Peritonitis

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Emergency medicine updates: Spontaneous bacterial peritonitis.

The American journal of emergency medicine, 2023

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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