Adverse hospital outcomes associated with the choice of empiric antibiotics in Klebsiella pneumoniae pneumonia : A retrospective observational study

Introduction: In Malaysia, Klebsiella pneumoniae ranks high as a cause of adult pneumonia requiring hospitalisation. Patients and Methods: With concern over its rising microbial resistance, we explored the association of empiric antibiotics choices with the hospital outcomes of patients treated for microbial proven K. pneumoniae pneumonia in an urban-based teaching hospital. Results: In 313 eligible cases reviewed retrospectively, hospital mortality and requirement for ventilation were 14.3% and 10.8% respectively. Empiric regimes that had in vitro resistance to at least one empiric antibiotic (n = 90) were associated with higher hospital mortality (23.3% vs. 10.8%, P= 0.004) with risk increased by about two-fold [Odds ratio (OR), 2.5; 95% confidence interval (CI), 1.3 to 4.8]. Regimes (n = 84) other than the commonly recommended "standard" regimes (a β-lactam stable antibiotic with or without a macrolide) were associated with higher ventilation rates (16.7% vs. 8.8%, P= 0.047) with similar increased risk [OR, 2.0; 95% CI, 1.0 to 4.3]. Conclusions: Our findings reiterate the clinical relevance of in vitro microbial resistance in adult K. pneumoniae pneumonia and support empiric regimes that contain β-lactam stable antibiotics.