PHILADELPHIA, PA—Initial treatment of patients hospitalized with aspiration pneumonia with anaerobe-specific antibiotics did not influence mortality or length of stay, compared to those without initial anaerobe-specific antibiotics, but patients without initial anaerobe coverage were more likely to change antibiotics, reported Hirokazu Ban, MD, from the Department of Internal Medicine, Mount Sinai Beth Israel, New York, NY, and colleagues, at IDWeek 2014.

The Infectious Disease Society of America/ American Thoracic Society (IDSA/ATS) guidelines state that anaerobic coverage is indicated for aspiration pneumonia only in patients presenting with specific risk factors like history of loss of consciousness as a result of alcohol/drug overdose or after seizures in concomitant gingival disease or esophageal motility disorders.

However, “clinicians often add anaerobic coverage in patients without these risk factors” noted Dr. Ban. His team evaluated the outcomes of patients with aspiration pneumonia that were treated with or without anaerobic-specific antibiotics.

This single-center retrospective cohort study included 388 patients (of 636 patients initially identified with a diagnosis code of aspiration pneumonia) that met the inclusion criteria between January 2008 and September 2013. 

Primary outcome was complete response to antibiotic coverage, defined as patients who demonstrated a normalization of vital signs and white blood cell count, symptomatic improvement, and a discharge from the hospital while remaining on the initial regimen. 

Similar Apache II (10.5±4.6 vs. 10.4±4.5) and PORT scores (110±30 vs. 108±32) were reported for 283 patients treated with anaerobe-specific antibiotics compared to 105 patients without anaerobe-specific antibiotics. 

Researchers found that patients treated with initial anaerobic coverage showed more complete response than those without initial anaerobic coverage (59% vs. 48%; P=0.045). No significant differences in length of stay (10.75 vs. 11.0 days; P=0.73), or mortality (13% vs. 17%; P=0.36) were detected. A change in antibiotics occurred more often in patients initially treated without anaerobic coverage (25% vs. 35% P=0.04); most of these changes (89%) consisted of adding anaerobic coverage. 

Dr. Ban and colleagues highlighted the need for larger studies comparing the 2 strategies in patients with aspiration pneumonia.