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Croup

Evidence last reviewed: 17 Sep 2026
Topic last updated: 07 Jan 2025

Summary

Definition

History and exam

Key diagnostic factors

  • symptoms increasing with agitation
  • distinctive seal-like barky cough
  • age 6 months to 6 years
Full details

Other diagnostic factors

  • male sex
  • peak season late autumn (North America)
  • prodromal symptoms
  • abrupt onset of symptoms
  • symptoms worse at night
  • hoarse voice
  • respiratory distress (sternal/intercostal indrawing, stridor)
  • persistent agitation
  • lethargy
  • asynchronous chest wall and abdominal movement
  • fatigue
  • signs of hypoxia (pallor or cyanosis)
  • signs of hypercapnia (decreased level of consciousness secondary to rising PaCO₂)
Full details

Risk factors

  • age 6 months to 6 years
  • male sex
  • prior intubation
Full details

Diagnostic tests

1st tests to order

  • clinical exam
Full details

Tests to avoid

  • viral panel testing
  • x-ray neck
Full details

Treatment algorithm

ACUTE

mild (no stridor at rest)

moderate (stridor at rest; no agitation or lethargy)

severe (stridor at rest with agitation or lethargy)

Contributors

Authors

Candice Bjornson, MSc, MD, FRCPC

Associate Professor

University of Calgary

Calgary

Canada

Disclosures

CB declares that she has no competing interests. CB is the author of several references in this topic.

David Johnson, MD

Professor

Department of Pediatrics and Physiology and Pharmacology

University of Calgary

Calgary

Canada

Disclosures

DJ declares that he has no competing interests. DJ is the author of several references in this topic.

Peer reviewers

Ken Farion, MD

Assistant Professor

Pediatrics and Emergency Medicine

University of Ottawa

Ottawa

Canada

Disclosures

KF declares that he has no competing interests.

Doreen Matsui, MD, FRCPC

Associate Professor

Departments of Paediatrics and Medicine

Children's Hospital of Western Ontario

London

Ontario

Canada

Disclosures

DM declares that she has no competing interests.

Jeremy Hull, MBBS

Consultant Paediatrician

Children's Hospital and West Wing

John Radcliffe Hospital

Oxford

UK

Divulgaciones

JH declares that he has no competing interests.

Steve Cunningham, MBBS, PhD

Consultant Respiratory Paediatrician

Department of Respiratory & Sleep Medicine

Royal Hospital for Sick Children

Edinburgh

UK

Divulgaciones

SC declares that he has no competing interests.

Donna J. Lee, MD

​Pediatric Pulmonology,

Joseph M. Sanzari Children's Hospital,

Hackensack Meridian Health

Hackensack

NJ

Divulgaciones

DL declares that he has no competing interests.

Deepak Mehta, MD, FRCS ( Oto)

​Professor of Otolaryngology,

Director Pediatric Aerodigestive Center,

Baylor College of Medicine,

Texas Children’s Hospital,

Houston

TX

Divulgaciones

DM declares that he has no competing interests.

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Referencias

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Artículos principales

Johnson D, Klassen T, Kellner J. Diagnosis and management of croup: Alberta Medical Association clinical practice guidelines. Alberta: Alberta Medical Association; 2015 [internet publication].Texto completo

Artículos de referencia

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