Recently updated guidelines for the diagnosis and treatment of adults with community-associated pneumonia, or CAP, stressed the importance of de-escalation of antibiotic therapy.

For adults with CAP being treated in the outpatient setting, the guidelines recommend against collecting sputum Gram’s stain and culture or blood cultures or performing urinary pneumococcal or Legionella antigen testing.

The guidelines recommend obtaining pretreatment Gram’s stain and culturing respiratory secretions for adult patients being managed in the hospital setting who have severe CAP, are being empirically treated for MRSA or Pseudomonas aeruginosa, were previously infected with MRSA or P. aeruginosa or were recently hospitalized and received parenteral antibiotics.

The guidelines recommend Legionella antigen testing only in patients with severe CAP or when Legionella is suspected due to an epidemiological factor — for example, because of an outbreak or a recent history of travel — whereas pneumococcal antigen testing should be performed only among patients with severe CAP.