Fast Five Quiz: Respiratory Syncytial Virus

Supatida Tengsupakul, MD


September 24, 2019

An initial diagnosis of acute bronchiolitis is generally based on history and physical examination findings. The specific causative organism can then be identified using antigen detection, molecular methods, or culture. Physicians may use any of the following tests to confirm RSV infection, which can help guide treatment decisions (such as to discontinue antibiotic treatment or palivizumab prophylaxis), determine the necessity of isolation, and educate families and caregivers:

  • Culture (HEp-2) is a standard for definitive diagnosis of RSV infection but is used infrequently in clinical settings.

  • Rapid antigen-detection test (turnaround time < 30 minutes) is useful in clinical settings owing to rapid turnaround time; however, it has lower sensitivity than the molecular method. Some laboratories perform an initial RSV rapid antigen test and confirm a negative result with a PCR-based technique.

  • Molecular-based methods (typically included as part of multiplex PCR assays) provide high sensitivity and are not affected by administration of an anti-RSV monoclonal antibody (palivizumab).

Laboratory studies, such as complete blood cell count, serum electrolyte concentrations, and C-reactive protein, may not be necessary in an uncomplicated case. Chest radiography can be useful in patients with persistent high fever to look for superimposed bacterial pneumonia, or in patients who do not have typical presentation of acute bronchiolitis to look for foreign body or evidence of congestive heart failure.

Learn more about tests used to confirm RSV infection.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.