Acute appendicitis

Last reviewed: 29 Aug 2023
Last updated: 16 Aug 2022



History and exam

Key diagnostic factors

  • abdominal pain
  • anorexia
  • right lower quadrant tenderness
More key diagnostic factors

Other diagnostic factors

  • age of occurrence
  • nausea
  • fever
  • diminished bowel sounds
  • tachycardia
  • vomiting
  • Rovsing sign
  • psoas sign
  • obturator sign
Other diagnostic factors

Risk factors

  • <6 months of breastfeeding
  • low dietary fiber
  • improved personal hygiene
  • smoking
More risk factors

Diagnostic investigations

1st investigations to order

  • CBC
  • CRP
  • abdominal and pelvic CT scan
  • urinary pregnancy test
More 1st investigations to order

Investigations to consider

  • abdominal ultrasound
  • urinalysis
  • abdominal and pelvic MRI in pregnancy
More investigations to consider

Treatment algorithm


uncomplicated acute appendicitis

ill with perforation or abscess



Peter Szasz, MD, PhD, FRCSC

Assistant Professor

Department of Surgery

Queen's University





PS declares that he has no competing interests.


Dr Peter Szasz would like to gratefully acknowledge Professor Ali Tavakkoli, Professor Dileep N. Lobo and Dr Nasim Ahmed, previous contributors to this topic. AT is a consultant for Medtronic. DNL is the author of an article cited in the topic. NA declares that he has no competing interests.

Peer reviewers

John M. Davis, MD

General Surgery

Jersey Shore Medical Center




JMD declares that he has no competing interests.

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