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Last reviewed: 16 Mar 2025
Last updated: 09 Aug 2022

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • fever or hypothermia
  • abdominal pain
  • rectal tenderness and fullness

Other diagnostic factors

  • tachycardia
  • change in bowel habits/abnormal bowel function
  • prolonged ileus
  • anorexia/lack of appetite
  • nausea and vomiting
  • palpable mass
  • signs of sepsis
  • pre-operative corticosteroid use

Risk factors

  • recent surgery or trauma, appendicitis, diverticulitis, or perforated ulcer

Diagnostic investigations

1st investigations to order

  • WBC count
  • drainage culture
  • abdominal CT scan

Investigations to consider

  • serum CRP
  • serum erythrocyte sedimentation rate (ESR)
  • Gram stain of abscess fluid
  • serum glucose
  • abdominal ultrasound
  • abdominal MRI scan

Emerging tests

  • endoscopic ultrasound

Treatment algorithm

Contributors

Authors

Laura Kreiner, MD, FACS

Assistant Professor of Surgery

MetroHealth Medical Center

Case Western Reserve University School of Medicine

Cleveland

OH

Disclosures

LK declares that she has no competing interests.

Acknowledgements

Dr Laura Kreiner would like to gratefully acknowledge Dr Ali F. Mallat, Dr Lena M. Napolitano, and Dr Lillian Kao, previous contributors to this topic.

Disclosures

AFM declares that he has no competing interests. LMN has been a member of the speakers' bureau and consultant for Merck, Pfizer, Schering-Plough, Ortho-McNeil, Wyeth, and Astellas Pharma. LK declares that she has no competing interests.

Peer reviewers

James T. Lee, MD, PhD, FACS, FIDSA, FSHEA

Professor of Surgery (retired)

University of Minnesota

Saint Paul

MN

Disclosures

JTL declares that he has no competing interests.

Jeffrey A. Claridge, MD, MS, FACS

Director of Research

Division of Trauma, Burns and Critical Care

Assistant Professor

Department of Surgery

MetroHealth Medical Center

Case Western Reserve University School of Medicine

Cleveland

OH

Disclosures

JAC declares that he has no competing interests.

Matthew Falagas, MD, MSc, DSc

Director

Alfa Institute of Biomedical Sciences

Marousi

Athens

Greece

Disclosures

MF declares that he has no competing interests.

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