Initial Antibiotic Choice for Community Acquired Pneumonia

Published - Written by John Staples

The basic symptoms which occur in pneumonia … are as follows: acute fever, sticking pain in the side, short rapid breaths, serrated pulse and cough.

  – Maimonides (1138–1204 AD)

Antibiotic treatment of community-acquired pneumonia (CAP) is one of the most remarkable medical developments of the 20th century, yet the choice of initial antibiotics is not without controversy. Current guidelines advise coverage for atypical organisms, but some investigators have pointed to the low incidence of atypical pathogens, the risk of fostering antibiotic resistance, and the specter of increased cardiac events with macrolides. What’s a clinician to do?

In an effort to shed light on this dilemma, Drs. D.F. Postma and C.H. van Werkhoven (University Medical Center, The Netherlands) and colleagues report on the results of the CAP-START study in this week’s NEJM. Seven Dutch hospitals were randomly assigned to treat patients admitted to non-ICU wards with CAP according to one of three antibiotic strategies: Beta-lactam monotherapy (such as ceftriaxone alone), beta-lactam/macrolide combination therapy (such as ceftriaxone plus azithromycin), or fluoroquinolone monotherapy (such as levofloxacin alone). Physicians could deviate from the strategy at their discretion. Hospitals crossed over to a different strategy every four months until trial completion, at which time a total of 2,283 patients had been recruited.

The investigators found that beta-lactam monotherapy was non-inferior to the other strategies, with similar crude 90-day mortality rates for all three groups (9%, 11%, and 9%, respectively). Median hospital length of stay was 6 days for all strategies.

“The non-inferiority of beta-lactam monotherapy for CAP is intriguing and should be considered in light of the risk of side effects (albeit small but not inconsequential) and the increasing burden of antimicrobial resistance,” says infectious disease specialist and NEJM Deputy Editor Dr. Lindsey Baden. “But readers should note that deviations from the recommended strategy for medical reasons occurred in about 25% of patients – suggesting there’s still a need for clinical judgment based on local and clinical factors.”

Unlike the pre-antibiotic era (when Sir William Osler called pneumonia “the Captain of the Men of Death”), modern medicine has a panoply of effective antibiotics from which to choose when a patient is admitted with CAP. What is the take-home message from CAP-START? Perhaps beta-lactam monotherapy is an adequate first volley to fire at the Captain.