Last updated: November 20, 2023

Summarytoggle arrow icon

Bronchiolitis is a lower respiratory tract infection (LRTI) characterized by inflammation of the bronchioles in children < 2 years of age. Respiratory syncytial virus (RSV) is the primary pathogen, although many viruses have been implicated in bronchiolitis. Patients first present with upper respiratory tract infection (URTI) symptoms (e.g., low-grade fever, nasal congestion) followed by a cough, wheezing, and, in severe cases, signs of acute respiratory distress. Bronchiolitis is a clinical diagnosis; diagnostic studies are usually not needed unless the child presents with severe illness that requires an evaluation for associated complications (e.g., superinfection, respiratory acidosis) or if the diagnosis is uncertain. Management consists of supportive treatment (e.g., nasal suction) and close monitoring. Severe illness requires hospitalization for additional management (e.g., IV fluids, respiratory support, nutritional support) and close monitoring of respiratory status. Bronchiolitis prevention includes RSV vaccination of pregnant individuals in the third trimester and routine passive immunization of all infants < 8 months of age with RSV monoclonal antibodies.

Epidemiologytoggle arrow icon

Epidemiological data refers to the US, unless otherwise specified.

Clinical featurestoggle arrow icon

If significant nasal congestion is present, provide nasal suction and reassess respiratory status to differentiate upper airway involvement (clear breath sounds after nasal suction) from lower airway involvement (abnormal breath sounds after nasal suction). [2]

Symptoms typically peak 3–5 days after onset and then gradually improve over 2–3 weeks. The onset of new symptoms or worsening of existing symptoms (e.g., fever) after 3–5 days should raise concern for complications of bronchiolitis. [1][2]

Diagnosticstoggle arrow icon

General principles [1][4]

Laboratory studies [1][2]

Chest x-ray in bronchiolitis

Managementtoggle arrow icon

Approach [1][7]

Children with bronchiolitis and oxygen saturation ≥ 90% do not require supplemental oxygen. [1][4]

Avoid bronchodilators, epinephrine, corticosteroids, antibiotics, and chest physiotherapy unless there are comorbidities (e.g., asthma, croup, cystic fibrosis, acute otitis media). [1]

Admission criteria for bronchiolitis [1][7][8]

Inpatient management of bronchiolitis [1][7]

Respiratory support

Hypertonic saline nebulizations may trigger bronchospasm. Discontinue treatment if nebulizations cause severe coughing fits and/or worsen the patient's respiratory status. [10]

Caloric and fluid support

  • Ensure patients receive the recommended daily intake for their age.
  • Encourage normal oral feeds (e.g., with breastmilk, formula, regular diet for age) as tolerated.
  • Consider NG/IV fluids for any of the following: [1]

Respiratory distress increases caloric and fluid requirements but also increases the risk for aspiration during oral feeds. Nutritional and fluid support via a feeding tube (orogastric or nasogastric) and/or intravenously is often necessary. [1]

Other recommendations

Outpatient management of bronchiolitis [1][7]

  • Arrange follow-up within 24 hours. [12]
  • Educate caregivers on:
    • Signs of deterioration and the need to seek immediate medical attention if present [12]
    • How and when to provide nasal suction
    • The expected course of disease
  • Encourage adequate oral caloric and fluid intake.
  • Advise caregivers to avoid exposing the patient to second-hand smoke; offer counseling on smoking cessation for household members.

Advise caregivers to seek immediate medical attention if the child shows signs of deterioration such as dehydration, poor feeding, lethargy or irritation, new fever, and/or signs of respiratory distress. [12]

Differential diagnosestoggle arrow icon

The differential diagnoses listed here are not exhaustive.

Complicationstoggle arrow icon

We list the most important complications. The selection is not exhaustive.

Prognosistoggle arrow icon

  • With timely diagnosis and adequate treatment, the prognosis is good.
  • Bronchiolitis in infancy is associated with an increased risk of developing asthma.

Preventiontoggle arrow icon

Administration of respiratory syncytial virus vaccine to pregnant individuals minimizes the risk of bronchiolitis in young infants. [14]

Related One-Minute Telegramtoggle arrow icon

Interested in the newest medical research, distilled down to just one minute? Sign up for the One-Minute Telegram in “Tips and links” below.

Referencestoggle arrow icon

  1. Brady MT, Byington CL, et al. Updated Guidance for Palivizumab Prophylaxis Among Infants and Young Children at Increased Risk of Hospitalization for Respiratory Syncytial Virus Infection. Pediatrics. 2014; 134 (2): p.e620-e638.doi: 10.1542/peds.2014-1666 . | Open in Read by QxMD
  2. Ralston SL, Lieberthal AS, Meissner HC, et al. Clinical practice guideline: the diagnosis, management, and prevention of bronchiolitis. Pediatrics. 2014; 134 (5): p.e1474-1502.doi: 10.1542/peds.2014-2742 . | Open in Read by QxMD
  3. Smith DK, Seales S, Budzik C. Respiratory Syncytial Virus Bronchiolitis in Children. Am Fam Physician. 2017; 95 (2): p.94-99.
  4. FDA Approves First Vaccine for Pregnant Individuals to Prevent RSV in Infants. . Accessed: August 22, 2023.
  5. Florin TA, Plint AC, Zorc JJ. Viral bronchiolitis. Lancet. 2017; 389 (10065): p.211-224.doi: 10.1016/s0140-6736(16)30951-5 . | Open in Read by QxMD
  6. Piedimonte G, Perez MK. Respiratory syncytial virus infection and bronchiolitis. Pediatr Rev. 2014; 35 (12): p.519-530.doi: 10.1542/pir.35-12-519 . | Open in Read by QxMD
  7. Kirolos A, Manti S, Blacow R, et al. A Systematic Review of Clinical Practice Guidelines for the Diagnosis and Management of Bronchiolitis. J Infect Dis. 2020; 222 (Supplement_7): p.S672-S679.doi: 10.1093/infdis/jiz240 . | Open in Read by QxMD
  8. Bedson W, Wilkinson E, Hawcutt D, Mcnamara P. Severity Scores used in the assessment of Bronchiolitis: A systematic review. Paediatric respiratory infection and immun. 2021.doi: 10.1183/13993003.congress-2021.oa2846 . | Open in Read by QxMD
  9. Zhang L, Mendoza-Sassi RA, Wainwright C, Klassen TP. Nebulised hypertonic saline solution for acute bronchiolitis in infants. Cochrane Database Syst Rev. 2017; 2017 (12).doi: 10.1002/14651858.cd006458.pub4 . | Open in Read by QxMD
  10. Siegel JD, Rhinehart E, Jackson M, Chiarello L. 2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Health Care Settings. Am J Infect Control. 2007; 35 (10): p.S65-S164.doi: 10.1016/j.ajic.2007.10.007 . | Open in Read by QxMD
  11. Walls R, Hockberger R, Gausche-Hill M. Rosen's Emergency Medicine. Elsevier Health Sciences ; 2018
  12. Di Cicco M, Kantar A, Masini B, Nuzzi G, Ragazzo V, Peroni D. Structural and functional development in airways throughout childhood: Children are not small adults. Pediatr Pulmonol. 2020; 56 (1): p.240-251.doi: 10.1002/ppul.25169 . | Open in Read by QxMD
  13. Vo AT, Liu DR, Schmidt AR, Festekjian A. Capillary blood gas in infants with bronchiolitis: Can end-tidal capnography replace it?. Am J Emerg Med. 2021; 45: p.144-148.doi: 10.1016/j.ajem.2021.04.056 . | Open in Read by QxMD
  14. McDaniel CE, Ralston S, Lucas B, Schroeder AR. Association of Diagnostic Criteria With Urinary Tract Infection Prevalence in Bronchiolitis. JAMA Pediatr. 2019; 173 (3): p.269.doi: 10.1001/jamapediatrics.2018.5091 . | Open in Read by QxMD

Icon of a lock3 free articles remaining

You have 3 free member-only articles left this month. Sign up and get unlimited access.
 Evidence-based content, created and peer-reviewed by physicians. Read the disclaimer