Bronchiolitis is swelling and mucus buildup in the smallest air passages in the lungs (bronchioles), usually due to a viral infection.
Causes, incidence, and risk factors
Bronchiolitis usually affects children under the age of 2, with a peak age of 3 - 6 months. It is a common, and sometimes severe illness. Respiratory syncytial virus (RSV) is the most common cause. More than half of all infants are exposed to this virus by their first birthday.
Other viruses that can cause bronchiolitis include:
Call your health care provider immediately, or go to the emergency room if the child with bronchiolitis:
Becomes extremely tired
Has bluish color in the skin, nails, or lips
Starts breathing very fast
Has a cold that suddenly worsens
Has difficulty breathing
Flares nostrils or retracts chest muscles in an effort to breathe
Most cases of bronchiolitis are not easily preventable because the viruses that cause the disorder are common in the environment. Careful attention to hand washing, especially around infants, can help prevent the spread of respiratory viruses.
Family members with an upper respiratory infection should be especially careful around infants. Wash your hands often, especially before handling the child.
At this date, there is no RSV vaccine available. However, there is an effective product, called palivizumab (Synagis), for infants who are at high risk of developing severe disease from RSV. Ask your child's doctor whether this medication is right for your child.
Watts KD, Goodman DM. Wheezing, bronchiolitis, and bronchitis. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 383.
American Academy of Pediatrics Subcommittee on the Diagnosis and Management of Bronchiolitis. Diagnosis and management of bronchiolitis. Pediatrics. 2006;118:1774-1793.
Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.