Diagnosis

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Diagnosis

Bronchiolitis is a clinical diagnosis that is based on typical history and examination. The peak severity of bronchiolitis usually occurs at day two to three of illness, with resolution over seven to ten days. The associated cough may persist for weeks. Bronchiolitis most commonly occurs in the winter months in temperate regions but can be seen year-round in tropical regions. 

Clinical signs and symptoms

Consider a diagnosis of bronchiolitis in an infant if they have an upper respiratory tract infection (rhinorrhoea, nasal congestion, and/or cough), followed by the onset of a lower respiratory tract infection involving one or more of the following: respiratory distress (tachypnoea and/or retractions), presence of diffuse crackles and/or wheeze. These symptoms may occur with or without the presence of fever. Additional signs and symptoms may include feeding difficulties, vomiting, dehydration, hypoxaemia, lethargy, and uncommonly (<5%) diarrhoea, and rarely (<2%) apnoea. (Evidence quality: very low; recommendation strength: weak)

Bronchiolitis is usually self-limiting, often requiring no treatment or interventions.