Nucleic acid amplification testing for CAP in adults

For adults with high-severity CAP, perform nucleic acid amplification testing (NAAT) (eg polymerase chain reaction [PCR]) to:

• confirm or exclude a viral diagnosis (eg influenza, COVID-19)
• confirm or exclude the presence of bacterial pathogens that are traditionally more difficult to isolate on culture (eg Mycoplasma pneumoniae, Legionella species)
• inform infection control management.

For adults with low- or moderate-severity CAP, consider NAAT (eg PCR) if the result is likely to aid decisions on management.

When available, sputum samples, endotracheal aspirates and bronchial lavage samples may provide greater yield for NAAT (eg PCR) than nose and throat swab samples; for advice on the most appropriate sample, refer to a local microbiological laboratory.

Refer to state and territory health department guidelines for advice on testing for severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection (COVID-19).

For a list of other clinical and microbiological investigations for CAP in adults, see Clinical and microbiological investigations for community-acquired pneumonia (CAP) in adults.