title: Long-Term Carriage of Ciprofloxacin-Resistant Escherichia coli Isolates in High-Risk Nursing Home Residents.
abstract: BACKGROUND Rates of multidrug-resistant gram-negative organisms are surpassing those of methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci in nursing homes (NHs). OBJECTIVE To characterize the incidence and duration of carriage of ciprofloxacin-resistant Escherichia coli (CipREc) in NHs and identify those in the O25b-ST131 lineage. METHODS We collected 227 CipREc isolates obtained by routine and regular surveillance of high-risk NH residents with indwelling devices. Repetitive element palindromic (REP)-polymerase chain reaction assay and multiplex polymerase chain reaction amplification for O25b-ST131 E. coli detection were performed using (GTG)5-primers and O25pabBspe and trpA2 primer pairs, respectively. RESULTS We found a high period prevalence of CipREc colonization (21.5%), high rates of recolonization with the same strain following clearing (0.46 recolonizations/ person/ year), and an acquisition incidence of 1.05 cases/1,000 person-days. Almost three-quarters of colonized residents carried strains in the O25b-ST131 E. coli lineage. Compared with isolates not in the lineage, O25b-ST131 isolates were carried significantly longer (10 vs 3 months). We identified 18 different REP-types; 2 occurred in 55% of the residents colonized with CipREc, and in more than 1 NH. Duration of CipREc carriage varied by REP-type and averaged 6 months. CONCLUSION CipREc occurred frequently in NH residents and is carried for long durations, and reacquisition following clearance is common Trial registration. ClinicalTrials.gov identifier: NCT01062841.
authors.affiliation: 1Center for Molecular and Clinical Epidemiology of Infectious Diseases,Department of Epidemiology,University of Michigan School of Public Health,Ann Arbor,Michigan.
authors.forename: Miriam D
authors.initials: MD
authors.lastname: Ismail
authors.affiliation: 1Center for Molecular and Clinical Epidemiology of Infectious Diseases,Department of Epidemiology,University of Michigan School of Public Health,Ann Arbor,Michigan.
authors.forename: Ting
authors.initials: T
authors.lastname: Luo
authors.affiliation: 2Infection Prevention in Aging Research Group,Division of Geriatric and Palliative Medicine,University of Michigan Medical School,Ann Arbor,Michigan.
authors.forename: Sara
authors.initials: S
authors.lastname: McNamara
authors.affiliation: 2Infection Prevention in Aging Research Group,Division of Geriatric and Palliative Medicine,University of Michigan Medical School,Ann Arbor,Michigan.
authors.forename: Bonnie
authors.initials: B
authors.lastname: Lansing
authors.affiliation: 2Infection Prevention in Aging Research Group,Division of Geriatric and Palliative Medicine,University of Michigan Medical School,Ann Arbor,Michigan.
authors.forename: Evonne
authors.initials: E
authors.lastname: Koo
authors.affiliation: 2Infection Prevention in Aging Research Group,Division of Geriatric and Palliative Medicine,University of Michigan Medical School,Ann Arbor,Michigan.
authors.forename: Lona
authors.initials: L
authors.lastname: Mody
authors.affiliation: 1Center for Molecular and Clinical Epidemiology of Infectious Diseases,Department of Epidemiology,University of Michigan School of Public Health,Ann Arbor,Michigan.
authors.forename: Betsy
authors.initials: B
authors.lastname: Foxman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002353:Carrier State / Q000453:epidemiology*; D002939:Ciprofloxacin / Q000627:therapeutic use*; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008824:Michigan; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009735:Nursing Homes; D012044:Regression Analysis; D016037:Single-Blind Method
chemical_list: D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin