Spontaneous bacterial peritonitis

Last reviewed: 29 Oct 2022
Last updated: 05 Nov 2021

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • abdominal pain or tenderness
  • signs of ascites
  • fever
  • nausea/vomiting
  • diarrhoea
  • altered mental status
  • gastrointestinal bleed
More key diagnostic factors

Other diagnostic factors

  • hypothermia
  • hypotension
  • tachycardia
Other diagnostic factors

Risk factors

  • decompensated hepatic state (usually cirrhosis)
  • low ascitic protein/complement
  • gastrointestinal bleeding
  • endoscopic sclerotherapy for oesophageal varices
  • ascites due to malignancy, renal insufficiency, or congestive heart failure
  • extra-intestinal infection
  • invasive procedures
More risk factors

Diagnostic investigations

1st investigations to order

  • FBC
  • serum creatinine
  • ascitic fluid appearance
  • ascitic fluid absolute neutrophil count (ANC)
  • ascitic fluid culture
  • blood cultures
  • LFT
  • PT/INR
More 1st investigations to order

Investigations to consider

  • highly-sensitive leukocyte esterase reagent strip testing of ascitic fluid (Periscreen)
  • bedside (standard urine) leukocyte esterase reagent strip testing of ascitic fluid
  • ascitic fluid protein, glucose, lactate dehydrogenase (LDH)
  • serum-ascites albumin gradient (SAAG)
  • ascitic fluid pH and arterial blood pH
  • ascitic fluid carcinoembryonic antigen (CEA)
  • ascitic fluid alkaline phosphatase
  • CT scan abdomen
More investigations to consider

Emerging tests

  • ascitic fluid lactoferrin
  • ascitic fluid PCR for bacterial DNA
  • serum procalcitonin

Treatment algorithm

ACUTE

community-acquired infection

nosocomial infection, septic shock, high risk for resistant species

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

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.

Kia Saeian, MD

Associate Professor of Medicine

Program Director

Gastroenterology Fellowship Program

Medical College of Wisconsin

Milwaukee

WI

Disclosures

KS declares that he has no competing interests.

Joseph K. Lim, MD

Assistant Professor of Medicine

Director

Yale Viral Hepatitis Program

Section of Digestive Diseases

Yale School of Medicine

New Haven

CT

Disclosures

JKL declares that he has no competing interests.

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  • Differentials

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    • Tuberculous peritonitis
    • Intraperitoneal haemorrhage into ascitic fluid
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  • Guidelines

    • Diagnosis, evaluation, and management of ascites, spontaneous bacterial peritonitis and hepatorenal syndrome
    • Guidelines on the management of ascites in cirrhosis
    More Guidelines
  • Videos

    Ascitic drainage animated demonstration

    More videos
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