BACKGROUND: There is a lack of consensus regarding the definition of risk 
factors for healthcare-associated infection (HCAI). The purpose of this study 
was to identify additional risk factors for HCAI, which are not included in the 
current definition of HCAI, associated with infection by multidrug-resistant 
(MDR) pathogens, in all hospitalized infected patients from the community.
METHODS: This 1-year prospective cohort study included all patients with 
infection admitted to a large, tertiary care, university hospital. Risk factors 
not included in the HCAI definition, and independently associated with MDR 
pathogen infection, namely MDR Gram-negative (MDR-GN) and ESKAPE microorganisms 
(vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus 
aureus, extended-spectrum beta-lactamase-producing Escherichia coli and 
Klebsiella species, carbapenem-hydrolyzing Klebsiella pneumonia and MDR 
Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species), were 
identified by logistic regression among patients admitted from the community 
(either with community-acquired or HCAI).
RESULTS: There were 1035 patients with infection, 718 from the community. Of 
these, 439 (61%) had microbiologic documentation; 123 were MDR (28%). Among MDR: 
104 (85%) had MDR-GN and 41 (33%) had an ESKAPE infection. Independent risk 
factors associated with MDR and MDR-GN infection were: age (adjusted odds ratio 
(OR) = 1.7 and 1.5, p = 0.001 and p = 0.009, respectively), and hospitalization 
in the previous year (between 4 and 12 months previously) (adjusted OR = 2.0 and 
1,7, p = 0.008 and p = 0.048, respectively). Infection by pathogens from the 
ESKAPE group was independently associated with previous antibiotic therapy 
(adjusted OR = 7.2, p < 0.001) and a Karnofsky index <70 (adjusted OR = 3.7, p = 
0.003). Patients with infection by MDR, MDR-GN and pathogens from the ESKAPE 
group had significantly higher rates of inadequate antibiotic therapy than those 
without (46% vs 7%, 44% vs 10%, 61% vs 15%, respectively, p < 0.001).
CONCLUSIONS: This study suggests that the inclusion of additional risk factors 
in the current definition of HCAI for MDR pathogen infection, namely age >60 
years, Karnofsky index <70, hospitalization in the previous year, and previous 
antibiotic therapy, may be clinically beneficial for early diagnosis, which may 
decrease the rate of inadequate antibiotic therapy among these patients.