Risk factors for drug-resistant pathogens in patients with hospital-acquired and ventilator-associated pneumonia

Abstract

Introduction: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are lethal nosocomial infections. Identifying patients at risk for drug-resistant pathogens (DRPs) is important to achieve appropriate antibiotic therapy and to reduce overuse of broad-spectrum antibiotics. The aim of this study is to clarify the risk factors for DRPs in patients with HAP and VAP at diagnosis.

Methods: This prospective observational study was conducted in adult patients with HAP and VAP at Nagoya University Hospital from March, 2010 through October, 2016. P. aeruginosa, methicillin-resistant S. aureus, extended-spectrum β-lactamase-producing Enterobacteriaceae, S. maltophilia, and multidrug-resistant A. baumannii were defined as DRPs. Multivariate logistic regression analysis was performed to assess risk factors for DRPs.

Results: In total, 504 patients (417: HAP, and 87: VAP) were analyzed. DRPs were identified in 127 (39%) of 327 culture-positive patients. Prevalence of DRPs in patients with and without history of prior DRP infection/colonization during the past year was 65% (60/92) and 29% (67/235), respectively. In patients without prior DRP history, Significant risk factors for DRPs were peripheral intravenous catheter (adjusted OR: 2.3, 95% CI: 1.2–4.4) and non-ambulatory status (2.0, 1.0–3.9). The following factors tended to increase the DRP risk: current hospitalization of ≥5 days (3.2, 0.9–11.8), chronic renal failure (2.1, 0.9–4.5), and hematocrit <30% (1.8, 0.9–3.3).

Conclusions: The prevalence of DRPs was ~40% in patients with HAP and VAP, and the risk factors for DRPs were elucidated. These factors should be considered for initial antibiotic selection.