Doxycycline may Reduce Risk of Clostridioides difficile Infection in community acquired Pneumonia patients

A recent retrospective analysis conducted in Veterans Affairs Hospitals across the United States suggests that doxycycline, a commonly used antibiotic, is associated with a lower risk of Clostridioides difficile infection (CDI) compared to azithromycin, particularly when used in the treatment of community-acquired pneumonia (CAP).

The study, published in the American Journal of Infection Control, involved an analysis of approximately 156,107 hospitalized patients diagnosed with CAP who received care at Veterans Affairs Hospitals. Researchers, led by Ashley L. O'Leary, Pharm.D., from the Veterans Affairs Western New York Healthcare System in Buffalo, aimed to investigate the potential link between doxycycline use and CDI risk reduction.

Their analysis revealed compelling findings. When doxycycline was used alongside ceftriaxone for pneumonia treatment, it demonstrated a 17% lower risk of CDI compared to azithromycin (P = .03). Moreover, among patients with a previous history of CDI, doxycycline use exhibited a significant reduction in the incidence of CDI by a substantial 45% (odds ratio 0.55; P = .02).

Senior author Kari A. Mergenhagen, Pharm.D., also from the Veterans Affairs Western New York Healthcare System, highlighted the significance of these results. "Our analysis found that in patients with a prior history of C. diff, doxycycline was the only factor associated with a reduction in the incidence of new C. diff infections," said Mergenhagen. "These results suggest that in cases where Legionella pneumonia can be ruled out prior to treatment, patients at increased risk of C. diff may benefit from the use of doxycycline as a first-line agent."

These findings provide valuable insights for clinicians treating patients with CAP, particularly those with an elevated risk of CDI. The study implies that doxycycline could be considered as a preferred first-line agent for atypical coverage in pneumonia treatment, especially when Legionella pneumonia is not a concern.

Reference:

O’Leary, A. L., Chan, A. K., Wattengel, B. A., Xu, J., & Mergenhagen, K. A. Impact of doxycycline on Clostridioides difficile infection in patients hospitalized with community-acquired pneumonia. American Journal of Infection Control,2023. https://doi.org/10.1016/j.ajic.2023.09.007