Prevalence and Risk Factors for Enterobacteriaceae (EB) and Multidrug-Resistant EB in Community-Acquired Pneumonia

Abstract

SESSION TITLE: Lung Infections SESSION TYPE: Original Investigation Slide PRESENTED ON: Tuesday, October 31, 2017 at 02:45 PM - 04:15 PM PURPOSE: Bacterial pathogens causing community-acquired pneumonia (CAP) have experienced an alarming increase in antimicrobial resistance during the last 10 years. Enterobacteriaceae (EB) family is known to involve potentially multidrug-resistant (MDR) microorganisms associated with high mortality that remain as an important cause of CAP. However, limited data are available regarding the actual prevalence and associated risk factors for EB and MDR-EB CAP. The aim of our study was to determine the prevalence and specific risk factors associated with EB and MDR-EB in a multicenter international cohort of adults hospitalized with CAP. METHODS: We performed a multinational (54 countries), multicenter (222 participating hospitals), point-prevalence study of adult patients (>18 years of age) admitted to the hospital due to CAP. EB patients with CAP included Klebsiella pneumoniae, Escherichia coli, Enterobacter spp., Proteus spp., and Serratia spp. We stratified the cohort according to the antimicrobial resistance to the major classes of antibiotic agents according to the Clinical Practice Guidelines. MDR-EB was defined when the identified pathogen was resistant to 3 or more antibiotic classes. We determined the prevalence of EB and MDR-EB among all patients with CAP and tested the association with 64 specific risk factors for EB and MDR-EB infection. RESULTS: Of 3,193 patients hospitalized with CAP, 197 (6%) had a positive culture with EB. Fifty one percent (n=100) of EB were resistant to at least one antibiotic, and 19% (n=38) were MDR-EB. The most commonly EB identified were K. pneumoniae (n = 111, 56%) and E. coli (n= 56, 28%). EB were resistant to fluoroquinolones (31%), piperacillin-tazobactam (30%), non-antipseudomonal cephalosporins (28%), aminoglycosides (14%) and carbapenems (8%). The risk factors that were independently associated with EB-CAP were prior extended-spectrum beta-lactamase (ESBL) infection (Odds ratio [OR] 3.6), underweight (OR 2.4), severe CAP (OR 2.4) and male gender (OR 1.5) (p value <0.05 for all). Additionally, prior ESBL infection (OR 8.2), enteral tube feedings (OR 3.5), underweight (OR 2.9), chronic liver disease (OR 2.7) and hospitalization in the past 12 months (OR 2.4) were independently associated with MDR-EB infection (p <0.05, for all risk factors). CONCLUSIONS: In our multicenter international study of adults hospitalized with CAP, the prevalence of EB was low (less than 10%). However, the presence of specific risk factors such as prior ESBL infection and underweight should raise the clinical suspicion for EB and MDR-EB in CAP patients. CLINICAL IMPLICATIONS: Clinicians should consider the prevalence of specific pathogens and evaluate for specific EB and MDR-EB risk factors before selection of empiric antimicrobial agents for adult patients hospitalized with CAP. DISCLOSURE: The following authors have nothing to disclose: David Villafuerte, Luis Reyes, Paola Faverio, Stefano Aliberti, Marcos Restrepo No Product/Research Disclosure Information