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 ATS/IDSA community-acquired pneumonia (CAP) guidelines recommend that clinicians prescribe empiric antibiotics for MRSA or P. aeruginosa only if locally validated risk factors (or 2 generic risk factors if local validation is not feasible) are present. It remains unknown how implementation of this recommendation would influence care.

Methods: This cross-sectional study included adults hospitalized for CAP across 50 hospitals in the Premier Healthcare Database from 2010-2015 and sought to describe how the use of extended-spectrum antibiotics (ESA) and the coverage for patients with CAP due to restraint organisms would change under the two approaches described in 2019 ATS/IDSA guidelines. To do this, 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 ESA, and 42%-100% of patients with resistant organisms received ESA. The median number of risk factors identified per hospital was 9 (interquartile range [IQR], 6-12). Overall, treatment according to local risk factors reduced the number of patients receiving ESA by 38.8 percentage points and using generic risk factors by 47.5 percentage points. 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 one hospital.

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