Acute appendicitis

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Last reviewed: 6 Apr 2025
Last updated: 17 Apr 2025

Summary

Definition

History and exam

Key diagnostic factors

  • abdominal pain
  • anorexia
  • nausea and vomiting
  • right lower quadrant tenderness
  • tense rigid abdomen
  • hypotension and tachycardia
  • palpable mass
Full details

Other diagnostic factors

  • age of occurrence
  • fever
  • flushed face and a fetor
  • diminished bowel sounds
  • tachycardia
  • loose stool
  • constipation
  • Rovsing sign
  • psoas sign
  • obturator sign
Full details

Risk factors

  • differences in the appendiceal microbiome
  • smoking
Full details

Diagnostic tests

1st tests to order

  • CBC
  • CRP
  • abdominal and pelvic CT scan
Full details

Tests to consider

  • abdominal ultrasound
  • urinalysis
  • urinary pregnancy test
  • abdominal and pelvic MRI in pregnancy
Full details

Emerging tests

  • Neutrophil-to-lymphocyte ratio
  • serum sodium
  • pentraxin-3
  • serum amyloid A
  • platelet indices
Full details

Treatment algorithm

ACUTE

uncomplicated acute appendicitis

ill with perforation or abscess

Contributors

Expert advisers

Peter Szasz, MD, PhD, FRCSC

Assistant Professor

Department of Surgery

Queen's University

Kingston

Ontario

Canada

Disclosures

PS declares that he has no competing interests.

Elisabeth Adderson, MD

Associate Member

St. Jude Children's Research Hospital

Associate Professor of Pediatrics

University of Tennessee Health Sciences Center

Memphis

TN

Disclosures

EA declares that she has no competing interests.

Peer reviewers

John M. Davis, MD

General Surgery

Jersey Shore Medical Center

Neptune

NJ

Disclosures

JMD declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Di Saverio S, Podda M, De Simone B, et al. Diagnosis and treatment of acute appendicitis: 2020 update of the WSES Jerusalem guidelines. World J Emerg Surg. 2020 Apr 15;15(1):27.Full text  Abstract

American College of Radiology. ACR appropriateness criteria: right lower quadrant pain - suspected appendicitis. 2022 [internet publication].Full text

Sartelli M, Chichom-Mefire A, Labricciosa FM, et al. The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections. World J Emerg Surg. 2017 Jul 10;12:29.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
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