Pneumococcal urinary antigen assay for CAP in adults

Consider performing pneumococcal urinary antigen assay to identify Streptococcus pneumoniae infection in adults with high-severity CAP, or if a positive result is likely to change therapy. The result may not change treatment decisions in patients already treated with benzylpenicillin or amoxicillin.

The pneumococcal urinary antigen assay can be performed on routine urine samples (either before or after starting antibiotic therapy), so is useful for the early identification of S. pneumoniae. Sensitivity for S. pneumoniae is increased in high-severity CAP, and pneumococcal pneumonia with bacteraemiaMetlay, 2019Wiersinga, 2018.

Do not use a pneumococcal urinary antigen assay to establish a diagnosis of CAPAthlin, 2022Bellew, 2019Greenfield, 2022Hyams, 2020Ito, 2021.

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 .