Acute appendicitis

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Last reviewed: 30 Sep 2024
Last updated: 04 Oct 2024

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

  • improved personal hygiene
  • 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

Forest W. Arnold, DO, MSc, FIDSA

Professor of Medicine

Chief, Division of Infectious Diseases

Director Infectious Diseases Fellowship Training Program

Department of Medicine

School of Medicine

University of Louisville

Louisville

KY

Disclosures

FWA declares that he has no competing interests.

Peer reviewers

Krishna Sundar, MD, FCCP

Associate Professor (Clinical)

Department of Medicine

University of Utah

Director

Pulmonary and Critical Care Research

IHC Urban South

Utah Valley Pulmonary Clinic

UT

Disclosures

KS declares that he has no competing interests.

Ozan Akca, MD

Director of Research

Associate Professor

Department of Anesthesiology and Perioperative Medicine

Neuroscience and Anesthesia Intensive Care Unit

University of Louisville

Louisville

KY

Disclosures

OA declares that he has no competing interests.

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  • Guidelines

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  • Calculators

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  • Patient information

    Appendicitis

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