What are the diagnostic criteria for croup (laryngotracheobronchitis)?

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From the Guidelines

Croup is primarily diagnosed based on clinical presentation, with key criteria including age, characteristic barking cough, stridor, hoarseness, onset, and physical examination findings. The diagnostic criteria for croup (laryngotracheobronchitis) can be broken down into several key components:

  • Age: Typically affects children 6 months to 3 years old, but can occur up to 6 years
  • Characteristic barking cough: A seal-like, harsh cough is the hallmark symptom
  • Stridor: Inspiratory stridor, a high-pitched breathing sound, is often present
  • Hoarseness: The child's voice may be hoarse or raspy
  • Onset: Symptoms often worsen at night and may be preceded by upper respiratory infection symptoms
  • Physical examination: May reveal mild respiratory distress, tachypnea, and suprasternal or intercostal retractions
  • Absence of drooling or difficulty swallowing, which would suggest other conditions like epiglottitis The Westley Croup Score can be used to assess severity, considering stridor, retractions, air entry, cyanosis, and level of consciousness 1. While not necessary for diagnosis, neck X-rays may show the classic "steeple sign" in severe cases. Croup is typically a clinical diagnosis, and additional tests are usually not required unless the presentation is atypical or severe. The diagnosis is based on the characteristic clinical features, with the barking cough and stridor being the most distinctive signs in the context of an upper respiratory infection in young children.

The clinical guideline and orderset used in the study 1 aimed to reduce hospital admissions for croup, highlighting the importance of accurate diagnosis and management in a clinical setting. The study included children with an ICD-10 discharge diagnosis of croup (J05.×, J38.×,) and collected data on age, race, and ethnicity to assess for differences in study groups that might impact disposition decision making.

In clinical practice, it is essential to prioritize the diagnosis of croup based on clinical presentation, as it is a common and typically self-limiting condition in children. A thorough clinical evaluation, including history and physical examination, is crucial for diagnosing croup and ruling out other potential causes of respiratory symptoms. The use of clinical guidelines and ordersets, as seen in the study 1, can help standardize the diagnosis and management of croup, ultimately reducing hospital admissions and improving patient outcomes.

From the Research

Diagnostic Criteria for Croup

The diagnostic criteria for croup, also known as laryngotracheobronchitis, are primarily based on clinical presentation, as stated in 2, 3, 4, 5. The key characteristics of croup include:

  • Inspiratory stridor
  • Barking cough
  • Hoarseness
  • Variable degree of respiratory distress
  • Low-grade fever (not necessary for diagnosis) 5

Clinical Diagnosis

Diagnosis is mainly clinical, with no specific confirmatory test, as mentioned in 2, 3, 5. Laboratory studies, such as viral cultures and rapid antigen testing, have minimal impact on management and are not routinely recommended 5. Radiography and laryngoscopy should be reserved for patients in whom alternative diagnoses are suspected 5.

Differential Diagnosis

The differential diagnosis of croup includes:

  • Epiglottitis
  • Retropharyngeal abscess
  • Bacterial tracheitis
  • Foreign body airway obstruction 3, 5

Assessment and Management

Assessment of airway, breathing, and circulation is crucial in treating croup, with a focus on airway, as stated in 4. The management of croup has altered dramatically over the years, with good evidence supporting the routine use of corticosteroids in all children with croup 2.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Viral croup: a current perspective.

Journal of pediatric health care : official publication of National Association of Pediatric Nurse Associates & Practitioners, 2004

Research

Croup.

The Journal of family practice, 1993

Research

Croup - assessment and management.

Australian family physician, 2010

Research

Croup: Diagnosis and Management.

American family physician, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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