Multidrug-resistant gram-negative bacteria in a long-term care facility: prevalence and risk factors.
OBJECTIVE
To quantify the prevalence, risk factors, and mode of transmission associated with colonization by multidrug-resistant gram-negative bacteria (MDRGN) in the long-term care (LTC) setting.


METHODS
Cross-sectional.


METHODS
Four nursing units in a 648-bed LTC facility in Boston, Massachusetts.


METHODS
Eighty-four long-term care residents.


METHODS
Nasal and rectal swabs were obtained to determine colonization with MDRGN; if present, molecular typing was performed. The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) was also determined. Demographic and clinical characteristics were obtained from the medical record. Multivariable analysis was used to identify factors independently associated with MDRGN colonization.


RESULTS
A total of 51%, 28%, and 4% subjects were colonized with MDRGN, MRSA, and VRE, respectively. After multivariable adjustment, advanced dementia (adjusted odds ratio (AOR)=2.9, 95% confidence interval (CI)=1.2-7.35, P=.02) and nonambulatory status (AOR=5.7, 95% CI=1.1-28.9, P=.04) were the only independent risk factors for harboring MDRGN. Molecular typing indicated person-to-person transmission.


CONCLUSIONS
Colonization with MDRGN is common in the LTC setting. A diagnosis of advanced dementia is a major risk factor for harboring MDRGN.
Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts02215, USA.
Aurora
A
Pop-Vicas
Susan L
SL
Mitchell
Ruth
R
Kandel
Robert
R
Schreiber
Erika M C
EM
D'Agata
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001900:Boston / Q000453:epidemiology; D003704:Dementia / Q000150:complications; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D006801:Humans; D008134:Long-Term Care; D008297:Male; D016106:Methicillin Resistance; D008875:Middle Aged; D009735:Nursing Homes; D015995:Prevalence; D012307:Risk Factors; D020713:Vancomycin Resistance