Identifying groups at high risk for carriage of antibiotic-resistant bacteria.
BACKGROUND
No simple, cost-effective methods exist to identify patients at high risk for methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci colonization outside intensive care settings. Without such methods, colonized patients are entering hospitals undetected and transmitting these bacteria to other patients. We aimed to develop a highly sensitive, simple-to-administer prediction rule to identify subpopulations of patients at high risk for colonization on hospital admission.


METHODS
We conducted a prospective cohort study of adult patients admitted to the general medical and surgical wards of a tertiary-care facility. Data were collected using electronic medical records and an investigator-administered questionnaire. Cultures of anterior nares and the perirectal area were also collected within 48 hours of admission.


RESULTS
Among 699 patients who enrolled in this study, 697 underwent nasal cultures; 555, perirectal cultures; and 553, both. Patient self-report of a hospital admission in the previous year was the most sensitive variable in identifying patients colonized with methicillin-resistant Staphylococcus aureus or with either organism (sensitivity, 76% and 90%, respectively). A prediction rule requiring patients to self-report having received antibiotics and a hospital admission in the previous year would have identified 100% of patients colonized with vancomycin-resistant enterococci. In the high-risk groups defined by the prediction rule, the prevalence of colonization by methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, or either organism were 8.1%, 10.2%, and 15.0%, respectively.


CONCLUSIONS
Patients with a self-reported previous admission within 1 year may represent a high-risk group for colonization by methicillin-resistant Staphylococcus aureus or vancomycin-resistant enterococci at hospital admission and should be considered for targeted active surveillance culturing.
Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore 21201, USA. jfuruno@epi.umaryland.edu
Jon P
JP
Furuno
Jessina C
JC
McGregor
Anthony D
AD
Harris
Judith A
JA
Johnson
Jennifer K
JK
Johnson
Patricia
P
Langenberg
Richard A
RA
Venezia
Joseph
J
Finkelstein
David L
DL
Smith
Sandra M
SM
Strauss
Eli N
EN
Perencevich
D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008396:Maryland / Q000453:epidemiology; D016106:Methicillin Resistance; D008875:Middle Aged; D009296:Nasal Cavity / Q000382:microbiology; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D013211:Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification