Bronchiolitis

Also known as: viral bronchiolitis, RSV bronchiolitis.

What is bronchiolitis?

Bronchiolitis is a common lung infection/inflammation affecting the small tubes (air passages-lower airways-bronchioles) to the lungs which usually affects children younger than 2 years of age, and which sometimes results in their hospitalization. The infection/inflammation causes swelling and secretions (mucus) that partially or completely block the bronchioles.

What causes bronchiolitis?

Risk factors include: being born preterm, never being breast fed, exposed to tobacco smoke, having an underlying heart or lung condition, a depressed immune system, living in a crowded environment, or being exposed to multiple young children. Bronchiolitis is almost always caused by a viral infection, typically the Respiratory syncytial virus (RSV), which infects infants < 3 years of age between November and April (in the USA). Other viral causes include influenza, parainfluenza or adenovirus.

What are the symptoms of bronchiolitis?

Following 1-3 days of common cold symptoms (stuffy nose, fever, decreased appetite, mild cough), breathing becomes more rapid (60-80 times per minute), the cough becomes persistent, and wheezing develops with trouble breathing and feeding. In small infants (premature ones or those < 2 months if age) periods of a pause in breathing (apnea) may be the first sign of bronchiolitis. With increasing severity, rib retractions (sucking in of the skin around the ribs or throat), flaring of the nostrils and grunting may occur and as the infant tires with the effort required to get oxygen into the lungs, and blue-tinged lips, fingernails and/or skin (cyanosis) from lack of oxygen indicates the seriousness of the condition and hospitalization will be required.

What are bronchiolitis care options?

There is no cure for bronchiolitis. Mild bronchiolitis may only require symptomatic treatment (fever control, nose drops or spray, fluids, etc.) at home. Most children will get better in 1-2 weeks.

If uncertain as to the severity, parents should seek immediate Emergency Department evaluation as this can be a life-threatening illness. Approximately 3% of children with bronchiolitis will require monitoring and treatment in hospital. Oxygen therapy, intravenous (IV) fluids, and a system to help the infant breathe (a breathing tube - endotracheal tube - and a machine to help breathing - a ventilator) may be required to support the child while the bronchioles heal.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: September 09, 2019 02:34 PM