• Viral infection (RSV) of bronchioles in children aged <2 years, most commonly in the first year of life, peaking between 3 and 6 months

• Symptoms usually peak between 3 and 5 days, and cough resolves in 90% of infants within 3 weeks.

Diagnosis

• Diagnose bronchiolitis if the child has a coryzal prodrome lasting 1-3 days, followed by persistent cough and either tachypnoea or chest recession (or both) and either wheeze or crackles on chest auscultation (or both)

Common symptoms

• fever (in around 30% of cases, usually of less than 39°C)

• poor feeding (typically after 3 to 5 days of illness)

• Young infants (in particular those aged <6W) may present with apnoea without other clinical signs

Differential diagnosis

• pneumonia (high fever (>39°C) and/or persistently focal crackles)

• viral-induced wheeze or early-onset asthma (older infants and young children with persistent wheeze without crackles or recurrent episodic wheeze or a personal or family history of atopy (these conditions are unusual in children aged <1Y))

• Measure oxygen saturation in every child presenting with suspected bronchiolitis

Referral

Suspect impending respiratory failure, and possible need for intensive care, if any of the following are present: 

• signs of exhaustion, for example listlessness or decreased respiratory effort; 

• recurrent apnoea; 

• failure to maintain adequate oxygen saturation despite oxygen supplementation

Immediately refer if: 

• apnoea (observed or reported)

• child looks seriously unwell

• severe respiratory distress, for example grunting, marked chest recession

• RR >70

• central cyanosis

• persistent 02 sats <92% on air

Consider referral if: 

• RR >60

• difficulty with breastfeeding or inadequate oral fluid intake

• clinical dehydration (take account of risk factors for severe bronchiolitis: chronic lung disease, congenital heart disease, age <3M, premature birth <32 weeks, neuromuscular disorders, immunodeficiency & factors that might affect a carer's ability to look after a child with bronchiolitis)

Management 

Do not use any of the following: 

• antibiotics

• hypertonic saline

• adrenaline (nebulised)

• salbutamol, montelukast, ipratropium bromide, systemic or inhaled corticosteroids

• a combination of systemic corticosteroids and nebulised adrenaline

Key safety information for looking after a child at home: 

• how to recognise developing 'red flag' symptoms:

  • exhaustion (for example, not responding normally to social cues, wakes only with prolonged stimulation)

  • apnoea or cyanosis

  • fluid intake is 50–75% of normal or no wet nappy for 12 hours

  • worsening work of breathing (for example grunting, nasal flaring, marked chest recession)

• that people should not smoke in the child's home because it increases the risk of more severe symptoms in bronchiolitis

• how to get immediate help from an appropriate professional if any red flag symptoms develop

• arrangements for follow-up if necessary​

References

• Bronchiolitis (NHS Choices)

• Bronchiolitis (patient.info)

• NICE. Bronchiolitis in children: diagnosis and management. NG9. 2015 (updated 2021).

• Bronchiolitis in children (SIGN, 2006)

• Cough - acute with chest signs in children - includes management of bronchiolitis (CKS)

QUESTION

You see a seven-month-old boy who has suffered with a cough for the last 48 hours. On examination he has a temperature of 38.7°C and a respiratory rate of 50 breaths per minute. His capillary refill time (CRT) is three seconds and he has mottled skin. Auscultation reveals fine inspiratory crepitations bilaterally. You suspect a diagnosis of bronchiolitis. A Covid-19 test is negative.

Which SINGLE feature on examination is a ‘red flag’ and would necessitate admission to hospital? 

1. Temperature 38.7 °C

2. Respiratory rate 50 breaths/minute

3. Mottled skin

4. Capillary refill time three seconds

5. Inspiratory crepitations on examination

This is a worrying picture of an unwell child.

The guidelines on managing feverish illness in children state that features that are high risk for serious illness should be assessed by paediatric specialists.

The following features are classified as high risk:

• Pale/mottled/ashen/blue skin, lips or tongue

• No response to social cues

• Appearing ill to a healthcare professional

• Does not wake or if roused does not stay awake

• Weak, high-pitched or continuous cry

• Grunting

• Respiratory rate greater than 60 breaths per minute

• Moderate or severe chest indrawing

• Reduced skin turgor

• Bulging fontanelle

A capillary refill time of three seconds or longer is classed as an intermediate-risk group marker for serious illness ('amber' sign).