Macrolide Resistance in Cases of Community-Acquired Bacterial Pneumonia in the Emergency Department

Abstract

Background: Emergency physicians are under pressure to prescribe an antibiotic early in the treatment course of a patient with community-acquired pneumonia (CAP). Macrolides are recommended first-line empirical therapy for the outpatient treatment of CAP in patients without associated comorbidities; however, resistance rates to macrolides in the United States are on the rise.

Objective: This review considers macrolide use for CAP in the emergency department by reviewing the microbiologic environment in the United States and whether macrolides can overcome in vitro resistance during actual clinical use. Alternatives to macrolides for CAP are briefly discussed.

Discussion: Resistance to macrolides is now above 25% in all regions of the United States, and resistance to other antibiotics is also on the rise. The failure of outpatient macrolide treatment for CAP because of resistance rates increases the burden of the disease both in terms of the patient and health economics. No definitive answer is available on whether macrolides will achieve treatment success despite infection with in vitro resistant strains. When selecting a therapy, a balance needs to be struck between spectrum of activity targeted against the probable etiology (including atypical pathogens) for respiratory tract infections and the need for first-time success.

Conclusions: Currently available macrolides are now facing resistance rates that cloud their recommendation as a first-line treatment for CAP. Clinicians need a better understanding of their own local resistance rates, while hospitals need to do a better job in describing low- and high-level resistance rates to better inform their physicians.

Keywords: CAP; antibiotic resistance; community-acquired pneumonia; emergency department; macrolide resistance.