In its latest clinical practice guideline on community-acquired pneumonia the American Thoracic Society’s guidelines panel addresses the use of nucleic acid-based testing for non-influenza viral pathogens. The guideline was published online in the May 1 issue of the American Journal of Respiratory and Critical Care Medicine. 

Community-acquired pneumonia is caused by a wide range of respiratory pathogens, prominently including viruses. However, the only viral pathogen addressed by the 2019 clinical practice guideline  was influenza. The panel determined that, given the increasing recognition of non-influenza viral causes of CAP and the expanded availability of diagnostic tests among clinicians, it was necessary to update the previous guideline to help guide treatment.

Using the Grading of Recommendations, Assessment, Development and Evaluation or GRADE framework, the panel made the following recommendations regarding the use of nucleic acid-based viral diagnostic testing for viral pathogens other than influenza in patients with suspected CAP:

Recommendation 1 In outpatients with suspected CAP, we suggest not performing routine nucleic-acid based testing of respiratory samples for viral pathogens other than influenza (conditional recommendation, very low-quality evidence)

Recommendation 2 In hospitalized patients with suspected CAP, we suggest nucleic acid-based testing of respiratory samples for viral pathogens other than influenza only in patients that meet one of the following conditions:

• Patients with severe CAP
• Immunocompromised patients (including neutropenia, active cancer therapy, history of solid organ or blood component transplant, advanced HIV disease, or chronic use of immunosuppressive medications including systemic corticosteroids). (conditional recommendations, very low-quality evidence)

“Molecular diagnostics for lung infections are rapidly evolving. We will continue to monitor developments to determine when additional updates are appropriate,” noted guideline panelists Scott Evans, MD and Charles Dela Cruz, MD, PhD. “We also look forward to reviewing more literature that directly link the use of molecular diagnostics on important outcomes, such as death, morbidity, antimicrobial drug use patterns, and costs.”