title: Anatomic, Geographic, and Taxon-Specific Relative Risks of Carbapenem Resistance in the Health Care System of the U.S. Department of Defense.
abstract: Carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter spp., and Enterobacteriaceae pose urgent public health threats. The differential burden, relative risks, associations with antimicrobial consumption, and temporal trends of those taxa in large, geographically diverse U.S. health systems remain under reported. Electronic records of all patients in a geographically dispersed 280-hospital managed-care system from 2005 to 2014 were reviewed. Carbapenem-resistant strains were identified based on Clinical and Laboratory Standards Institute guidelines and breakpoints. A total of 360,000 potentially carbapenem-resistant strains were identified from 14.7 million cultures (80% infecting and 20% surveillance). Isolation of bacteria overseas or isolation from the bloodstream was associated with a higher relative risks of carbapenem resistance (CR; P < 0.0001). Enterobacteriaceae were isolated 11 times more frequently than P. aeruginosa and Acinetobacter spp. However, compared to Enterobacteriaceae, the CR levels were 73-fold and 210-fold higher in P. aeruginosa and Acinetobacter spp., respectively. Significant differences in the relative risk of CR between taxa, anatomic, and geographic locations persisted after adjustment for other variables, the biggest differences occurring between taxa. Overall, CR rates increased for Enterobacteriaceae (P = 0.03) and decreased for Acinetobacter spp. and P. aeruginosa (P < 0.0001). These data provide a useful baseline for resistance trending and have implications for surveillance. Infections acquired overseas and bloodstream infections are particularly important areas for continued monitoring.
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA emil.p.lesho.mil@mail.mil.
authors.forename: Emil
authors.initials: E
authors.lastname: Lesho
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia, USA.
authors.forename: Uzo
authors.initials: U
authors.lastname: Chukwuma
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Sparks
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia, USA.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Neumann
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, Landstuhl Regional Medical Center, Landstuhl, Germany.
authors.forename: Douglas
authors.initials: D
authors.lastname: Richesson
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Clifford
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Gierhart
authors.affiliation: Global Emerging Infection Surveillance Section, Armed Forces Health Surveillance Branch, Silver Spring, Maryland, USA.
authors.forename: Paige
authors.initials: P
authors.lastname: Waterman
authors.affiliation: Antibiotic Resistance Monitoring and Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Hinkle
mesh_terms: D000150:Acinetobacter / Q000187:drug effects / Q000302:isolation & purification*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D004755:Enterobacteriaceae / Q000187:drug effects / Q000302:isolation & purification*; D005260:Female; D005843:Geography; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology; D006268:Health Facilities; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D058749:Military Facilities; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000302:isolation & purification*; D012306:Risk; D014481:United States; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems