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Spontaneous bacterial peritonitis

Last reviewed: 6 Feb 2025
Last updated: 13 Feb 2025

Summary

Definition

History and exam

Key diagnostic factors

  • abdominal pain or tenderness
  • signs of ascites
  • fever
  • nausea/vomiting
  • diarrhea
  • altered mental status
  • gastrointestinal bleed
Full details

Other diagnostic factors

  • hypothermia
  • hypotension
  • tachycardia
Full details

Risk factors

  • decompensated hepatic state (usually cirrhosis)
  • low ascitic protein/complement
  • gastrointestinal bleeding
  • endoscopic sclerotherapy for esophageal varices
  • ascites due to malignancy, renal insufficiency, or congestive heart failure
  • extraintestinal infection
  • invasive procedures
  • use of proton-pump inhibitors (PPIs)
Full details

Diagnostic tests

1st tests to order

  • CBC
  • serum creatinine
  • LFT
  • prothrombin time/INR
  • blood cultures
  • ascitic fluid appearance
  • ascitic fluid absolute neutrophil count (ANC)
  • ascitic fluid culture
  • ascitic fluid protein, glucose, lactate dehydrogenase (LDH), pH
Full details

Tests to consider

  • serum-ascites albumin gradient (SAAG)
  • ascitic fluid carcinoembryonic antigen (CEA)
  • ascitic fluid alkaline phosphatase
  • ascitic fluid AFB stain and culture, fungal culture, microscopy for ova/parasites
  • ascitic fluid lactoferrin
  • CT scan abdomen
Full details

Emerging tests

  • highly-sensitive leukocyte esterase reagent strip testing of ascitic fluid (Periscreen)
  • bedside (standard urine) leukocyte esterase reagent strip testing of ascitic fluid

Treatment algorithm

ACUTE

community-acquired infection with low risk for resistant species

nosocomial infection, septic shock, high risk for MDR organisms

Contributors

Authors

Brian Chinnock, MD

Associate Professor of Emergency Medicine

UCSF Fresno Medical Education Program

Fresno

CA

Disclosures

BC is an author of references cited in this topic.

Peer reviewers

Ke-Qin Hu, MD

Director, Hepatology Services, H.H. Chao Comprehensive Digestive Disease Center

Professor of Medicine

School of Medicine

University of California, Irvine

Irvine

CA

Disclosures

KQH declares that he has no competing interests.

Andrea De Gottardi, MD, PhD

Visiting Hepatologist

Hepatic Hemodynamic Laboratory

Liver Unit

Hospital Clinic

Barcelona

Spain

Disclosures

ADG declares that he has no competing interests.

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