Bronchiolitis

Bronchiolitis is inflammation of the small airways also known as the bronchioles in the lungs. Acute bronchiolitis is caused by a viral infection, usually affecting children younger than two years of age. Symptoms may include fever, cough, runny nose or rhinorrhea, and wheezing. More severe cases may be associated with nasal flaring, grunting, or respiratory distress. If the child has not been able to feed properly due to the illness, signs of dehydration may be present.

Chronic bronchiolitis is more common in adults and has various causes, one of which is bronchiolitis obliterans. Often when people refer to bronchiolitis, they are referring to acute bronchiolitis in children.

Acute bronchiolitis is usually the result of viral infection by respiratory syncytial virus (RSV) (59.2% of cases) or human rhinovirus (19.3% of cases). Diagnosis is generally based on symptoms. Tests such as a chest X-ray or viral testing are not routinely needed, but may be used to rule out other diseases.

There is no specific medicine that is used to treat bronchiolitis. Symptomatic treatment at home is generally effective and most children do not require hospitalization. This can include antipyretics such as acetaminophen for fever and nasal suction for nasal congestion, both of which can be purchased over the counter. Occasionally, hospital admission for oxygen, particularly high flow nasal cannula, or intravenous fluids is needed in more severe cases of disease.

About 10% to 30% of children under the age of two years are affected by bronchiolitis at some point in time. It commonly occurs in the winter season in the Northern Hemisphere. It is the leading cause of hospitalizations in those less than one year of age in the United States. The risk of death among those who are admitted to hospital is extremely low at about 1%. Outbreaks of the condition were first described in the 1940s.