Bronchiolitis is the leading cause of hospital admission in infants under 1 year of age.
Respiratory syncytial virus (RSV) is the most common cause.
Most cases are mild and self-limiting, and supportive care is the only indicated therapy.
Cough may persist for weeks, after 10 to 14 days of acute illness. Some patients may go on to develop recurrent wheeze.
Viral bronchiolitis is an acute viral infection of the lower respiratory tract. Although it can affect individuals of any age, the term is most often used to refer to infection in infancy. It is characterised by epithelial cell destruction, cellular oedema, and airway obstruction by inflammatory debris and mucus. The clinical manifestations include cough, wheeze, and laboured breathing. Respiratory syncytial virus (RSV) accounts for the majority of cases, although rhinovirus, human metapneumovirus, bocavirus, influenza, parainfluenza, and adenovirus can all cause bronchiolitis as well.
History and exam
Key diagnostic factors
- presence of risk factors
- retractions, grunting, and nasal flaring
Other diagnostic factors
- fluctuating clinical findings
- irritability, malaise, and poor feeding
- fever <40°C (<104°F)
- thoracoabdominal asynchrony
- infants <3 years
- winter months
- prematurity or bronchopulmonary dysplasia
- passive tobacco smoke exposure and air pollution
- impaired airway clearance and function
- congenital heart disease
1st investigations to order
- pulse oximetry
Investigations to consider
- enzyme-linked immunosorbent assay (ELISA) rapid antigen detection
- chest x-ray
- reverse transcriptase polymerase chain reaction (RT-PCR)
- infant pulmonary function tests
infants at high risk of severe RSV infection
- Bacterial pneumonia
- Chlamydial pneumonia
- Cystic fibrosis (CF)
- Bronchiolitis in children: diagnosis and management
- Fever in under 5s: assessment and initial management
Asthma in children: what is it?More Patient leaflets
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