- Clinical science
Bronchiolitis is a lower respiratory tract infection (RTI) in which the bronchioles become inflamed because of a viral infection. Most often, the respiratory syncytial virus (RSV) is responsible. The infection occurs mainly in children below the age of two and is characterized by initial upper RTI symptoms (low-grade fever, stuffy nose) followed by a cough and possibly signs of respiratory distress (i.e., tachypnea, wheezing, nasal flaring, intercostal retractions, cyanosis) that may require hospitalization. Ill children should be closely monitored and receive oxygen and proper hydration for supportive therapy.
- Primarily affects children < 2 years
- Peak incidence: 2–6 months of age
- Common during winter months
Epidemiological data refers to the US, unless otherwise specified.
- Initially presents with upper respiratory tract symptoms (e.g., rhinorrhea), fever, and cough
Respiratory distress (usually occurs in infants)
- Tachypnea, prolonged expiration
- Nasal flaring, intercostal retractions
- Poor feeding in breastfed infants
- Auscultatory findings: wheezing, crackles
An upper RTI followed by symptoms of respiratory distress and wheezing in a child < 2 years of age should prompt evaluation for bronchiolitis!
- Supportive treatment (adequate hydration, relief of nasal congestion/obstruction, monitoring)
- Indications for hospitalization: risk factors for severe bronchiolitis
- Inpatient management: supportive treatment and monitoring of oxygen status
- Bronchodilators, epinephrine, and corticosteroids have historically been part of the treatment for bronchiolitis, but recent guidelines no longer recommend them.
- Ribavirin (antiviral synthetic nucleoside analog): currently not recommended for routine treatment of bronchiolitis; may be considered in immunocompromised patients
- Respiratory failure
We list the most important complications. The selection is not exhaustive.
- With timely diagnosis and adequate treatment, the prognosis is good
- Bronchiolitis in infancy is associated with an increased risk of developing asthma.