Potential Implications of Using Locally Validated Risk Factors for Drug-Resistant Pathogens in Patients With Community-Acquired Pneumonia in US Hospitals: A Cross-Sectional Study.

Background: The 2019 American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) community-acquired pneumonia (CAP) guidelines recommend that clinicians prescribe empiric antibiotics for methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa only if locally validated risk factors (or 2 generic risk factors if local validation is not feasible) are present.

Methods: In this cross-sectional study that included adults hospitalized for CAP across 50 hospitals in the Premier Healthcare Database from 2010 to 2015, we sought to describe how the use of extended-spectrum antibiotics (ESAs) and the coverage for patients with CAP due to restraint organisms would change under the 2 approaches described in the 2019 ATS/IDSA guidelines. The proportion of ESA use in patients with CAP and the proportion of ESA coverage among patients with infections resistant to recommended CAP therapy were measured.

Results: In the 50 hospitals, 19%-75% of patients received ESAs, and 42%-100% of patients with resistant organisms received ESAs. The median number of risk factors identified per hospital was 9 (interquartile range, 6-12). Overall, treatment according to local risk factors reduced the number of patients receiving ESAs by 38.8 percentage points and by 47.5 percentage points when using generic risk factors. However, the effect varied by hospital. The use of generic risk factors always resulted in less ESA use and less coverage for resistant organisms. Using locally validated risk factors resulted in a similar outcome in all but 1 hospital.

Conclusions: Future guidelines should explicitly define the optimal trade-off between adequate coverage for resistant organisms and ESA use.