Moxifloxacin monotherapy versus combination therapy in patients with severe community-acquired pneumonia evoked ARDS

Background: We tested the hypothesis that moxifloxacin monotherapy is equally effective and safe as a betalactam antibiotic based combination therapy in patients with acute respiratory distress syndrome (ARDS) evoked by severe community acquired pneumonia (CAP). Methods: In a retrospective chart review study of 229 patients with adult respiratory distress syndrome (ARDS) admitted to our intensive care unit between 2001 and 2011, 169 well-characterized patients were identified to suffer from severe CAP. Patients were treated with moxifloxacin alone, moxifloxacin in combination with beta-lactam antibiotics, or with another antibiotic regimen based on beta-lactam antibiotics, at the discretion of the admitting attending physician. The primary endpoint was 30-day survival. To assess potential drug-induced liver injury, we also analyzed biomarkers of liver cell integrity. Results: 30-day survival (69% overall) did not differ (p = 0.89) between moxifloxacin monotherapy (n = 42), moxifloxacin combination therapy (n = 44), and other antibiotic treatments (n = 83). We found significantly greater maximum activity of aspartate transaminase (p = 0.048), alanine aminotransferase (p = 0.003), and direct bilirubin concentration (p = 0.01) in the moxifloxacin treated groups over the first 10-20 days. However, these in-between group differences faded over time, and no differences remained during the last 10 days of observation. Conclusions: In CAP evoked ARDS, moxifloxacin monotherapy and moxifloxacin combination therapy was not different to a betalactam based antibiotic regimen with respect to 30-day mortality, and temporarily increased markers of liver cell integrity had no apparent clinical impact. Thus, in contrast to the current S3 guidelines, moxifloxacin may also be safe and effective even in patients with severe CAP evoked ARDS while providing coverage of an extended spectrum of severe CAP evoking bacteria. However, further prospective studies are needed for definite recommendations.