RESULTS INTRODUCTION METHODS CONCLUSION  Extended spectrum beta-lactamases producing Enterobacteriacae (ESBLPE) have become a major cause of hospital-acquired infections.  Consequences: -limitation of effective antimicrobial drug therapy - adverse patient outcome  Since last decade, ESBL-PE carrying CTX-M enzymes have spread in the community  Hospitalization of asymptomatic colonized patient from the community may serve as reservoir for further cross-transmission to other hospitalized patients  The objectives of this study were to: evaluate the duration of ESBL-PE carriage after hospital discharge factors associated with clearance of ESBLPE carriage  Importation of ESBLPE in hospital settings from the community constitute a starting point for their spread to nearby patients  ESBLPE carriers had long length of hospital stay with a high risk of readmission within 30 days after hospital discharge 2  The difference median time to ESBLPE clearance with 2 previous study (198 days vs 98 and 136 days) were probably due to the populations studied and the strategy of follow- up 3,4  Associations between time of clearance and length of hospital stay > 7 days could be explained by the use of carbapenem which could decrease the gut colonization.  The association with the period of positivity could be explained the shorter follow-up during the last years of study  The long time persistence of ESBLPE carriage after hospital discharge make the screening and contact- isolation precautions at readmission advisable for all patients identified positive during an earlier hospital stay with the help of an automatic alert system.  Prospective surveillance of ESBLPE colonizations/infections from 1st January 1997 to 31 December 2010 in a 1000-bed University Hospital  Data collection: Demographical, Microbiological data and Hospital stay characteristics on ESBLPE colonizations/infections were prospectively collected  Population studied: newly admitted patient known as colonized and/or infected during a previous hospitalization identified by an automatic alert system 1 oSystematic contact-isolation precautions o Rectal swabbing if readmission > 3 months after a previous hospital discharge  Clearance : 1 negative rectal screening at the time of the readmission  Imported cases: carriage discovered within 48 h and infection within 72 h after admission,  Duration of carriage: difference between date of positive readmission and date of hospital discharge following the first positive culture  Microbiological techniques: Culture on Drigalski lactose agar and ChromID ESBL for ESBLPE screening. Susceptibility: agar diffusion method + synergy test  Data analysis: Univariate (Wilcoxon rank-sum test, 2- tailed Fischer’s exact tests) and a multivariate analysis (Cox model)  ESBL-PE was isolated from 1884 patients cumulating 2734 hospital admissions and 220 visits mainly in medical units for 2239 (41.4%), ICUs for 1699 (31%) and surgical units for 941 (17%)  ESBL-PE was imported in 951 (50.5%) and acquired in 924 (49%)  Median time to colonization: 16 days [9 - 29]  ESBL-PE strains isolated: E.coli, 1093 (51.9%); K.pneumoniae, 438 (20.8%); Enterobacter spp., 423 (20.1%).  Incidence of ESBL-PE: from 0.11 in 1997 to 0.98/1,000 Patients/days in  503 readmitted patients with a median delay of 27 days (10 – 67) after hospital discharge  449 patients screened: 181 (40.3%) ESBL positive culture and 268 (59.7%) negative.  Median time of ESBL clearance: 6.6 months (4.3 – 14.6)  Variables associated with a shorter duration of clearance (Table 1): o a first positive culture during the period , HR;95% CI= 1.65 [ ] o a length of hospital stay >7 days after a previous positive culture, 1.51 ( ) 51st ICAAC, th of September 2011, Chicago 1.Pittet D, Safran E, Harbarth S, et al. Automatic alerts for methicillin-resistant Staphylococcus aureus surveillance and control: role of a hospital information system. Infect Control Hosp Epidemiol 1996;17: Westert GP, Lagoe RJ, Keskimaki I, Leyland A, Murphy M. An international study of hospital readmissions and related utilization in Europe and the USA. Health Policy 2002;61: Apisarnthanarak A, Bailey TC, Fraser VJ. Duration of stool colonization in patients infected with extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae. Clin Infect Dis 2008;46: Zahar JR, Lanternier F, Mechai F et al. Duration of colonisation by Enterobacteriaceae producing extended-spectrum beta-lactamase and risk factors for persistent faecal carriage. J Hosp Infect May;75(1):76-8. Duration of Colonization by Extended Spectrum β-Lactamase producing Enterobacteriaceae after Hospital Discharge G Birgand 1, L Armand-Lefevre 2,3, I Lolom 1, E Ruppe 2,3, A Andremont 2,3, JC Lucet 1 1 Infection control unit, Bichat-Claude Bernard hospital, Paris, France 2 Bacteriology laboratory 3 EA 3964 University Paris 7, Paris France. The duration of digestive colonization with extended spectrum β-lactamase producing enterobacteriacae (ESBLPE) may play a major role in their spread. We evaluated the duration of and factors associated with clearance of ESBLPE carriage in the hospital setting. Retrospective study based on a 14-year ( ) prospective surveillance of inpatients (Pts) colonized with ESBLPE in a 1000-bed University Hospital. An automatic alert system identified readmitted Pts with a history of ESBLPE, and readmission screening was recommended. Pts were considered cleared from ESBLPE after one negative rectal sample, and the absence of new positive clinical sample during the stay. Demographic, hospital stay and microbiological data and outcome were prospectively collected. We performed survival analysis; variables associated with clearance of ESBLPE were estimated with a Cox model. A total of 1884 Pts (2734 admissions) were included. The incidence of ESBLPE in clinical isolates increased from 0.11 (K. pneumoniae, 42.4%) in 1997 to 0.98/1000 Pts.day (E. coli, 54.7%) in Species carrying the ESBLs (n=2102) were E. coli (1093 Pts, 51.9%), Enterobacter spp. (438, 20.8%) and K. pneumoniae (423, 20.1%) in clinical samples of 1221 Pts (65%) and/or in screening samples of 1086 (58%). Detection occurred ≥72 hours after admission in 924 (49%) Pts. 448 (24%) Pts had 1 to 16 readmissions, and 180 (40%) were persisting carriers. The median time of ESBLPE clearance was 6.6 months. Independent variables associated with clearance were a length of stay >7 days after a previous positive culture (aHR, 1.51; 95%CI, ), and the first positive culture during (1.65, ). There was no difference between the type of enterobacteriaceae. An automatic alert system was useful to identify, screen and isolate previous ESBLPE carriers. ESBLPE carriage was unexpectedly prolonged in Pts with short hospital stays. Recent years may be associated with shorter carriage. ABSTRACT Figure 1: Kaplan-Meier estimate of time until results of screenings for ESBLPE became negative for readmitted patients (%), Table 1: Variables associated with clearance of ESBLPE carriage using a Cox hazard proportional model K Bichat – Claude Bernard Hospital 46 rue Henri Huchard Paris Phone: Fax: Figure 2. Incidence of global ESBLPE cultured from screening or clinical samples, January 1997 to December 2010,