Anorectal abscess

Last reviewed: 25 Apr 2022
Last updated: 20 Sep 2019

Summary

Definition

History and exam

Key diagnostic factors

  • anal fistula
  • history of Crohn disease
  • male sex
  • perianal pain
  • perianal or rectal induration
More key diagnostic factors

Other diagnostic factors

  • perianal swelling
  • low-grade fever
  • tachycardia
  • change in bowel habits
  • rectal bleeding
  • inability to urinate
Other diagnostic factors

Risk factors

  • anal fistula
  • Crohn disease
  • male sex
  • hard stools
  • age 20 to 40 years
More risk factors

Diagnostic investigations

1st investigations to order

  • clinical examination
  • examination under anesthetic
More 1st investigations to order

Investigations to consider

  • WBC count
  • serum glucose
  • serum electrolytes
  • anal ultrasonography
  • CT pelvis
  • MRI pelvis
  • microscopic examination and/or culture of the purulent fluid
More investigations to consider

Treatment algorithm

ACUTE

all patients

Contributors

Authors

Jan Rakinic, MD, FACS, FASCRS

Professor of Surgery

Chief

Section of Colorectal Surgery

Southern Illinois University School of Medicine

Springfield

IL

Disclosures

JR is an author of a reference cited in this topic.

Acknowledgements

Dr Jan Rakinic would like to gratefully acknowledge Dr C. Neal Ellis, a previous contributor to this topic. CNE declares that he has no competing interests.

Peer reviewers

Mark H. Whiteford, MD

Assistant Professor of Surgery

Colon and Rectal Surgery

Gastrointestinal and Minimally Invasive Surgery Division

The Oregon Clinic

Portland

OR

Disclosures

MHW declares that he has no competing interests.

Neil Hyman, MD

Chief

Division of General Surgery

Professor of Surgery

Fletcher Allen Healthcare

Burlington

VT

Disclosures

NH declares that he has no competing interests.

Steven Brown, MBChB, FRCS, MD, BMedSci

Consultant Surgeon

Department of Colorectal Surgery

Sheffield Teaching Hospitals

Sheffield

UK

Disclosures

SB declares that he has no competing interests.

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