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The mechanism(s) of acquisition of extended-spectrum cephalosporin-resistant Enterobacteriaceae(ESCRE) on inpatient hospital units dedicated to hematopoietic stem cell transplantation (HSCT) is unclear. The objectives of this study were to determine whether ESCRE organisms are transmitted among patients housed on a HSCT unit, clarify the mechanisms involved, and determine whether routine surveillance for ESCRE carriage and contact isolation for ESCRE carriers is beneficial. The study was conducted on a 30-bed inpatient unit dedicated to the care of patients with hematologic malignancies and HSCT recipients. To investigate whether ESCRE organisms may be transmitted vertically to subsequent room occupants, presumably through contamination of room surfaces, we (1) cultured 6 high touch areas in 10 rooms before and 9 rooms after terminal cleaning that had been occupied by patients with ESCRE carriage, (2) determined the in vitro survivals of our most common clinical ESCRE species, and (3) followed the subsequent room occupants of 54 consecutive ESCRE colonized patients for the development of inpatient acquired ESCRE carriage. To investigate whether ESCRE organisms are transmitted horizontally among inpatients we (1) sequenced 60 available ESCRE Escherichia coliisolates obtained from unit inpatients and searched for identities using complete-genome multisequence locus typing (cgMLST) and (2) retrospectively tabulated the cumulative rates of acquired ESCRE carriage in 356 patients admitted for a first HSCT before (200 patients) or after (156 patients) institution of universal ESCRE stool surveillance and contact isolation for carriers. No ESCRE organisms were cultured from patient rooms before or after terminal cleaning. In vitro, few, if any, ESCRE organisms survived longer than 2 hours. Nine of the subsequent occupants of a room in which a patient with ESCRE carriage had resided were detected with ESCRE carriage, only 2 of whom carried the same species as that of the prior occupant. DNA sequencing and cgMLST determination of the 60 E. coliisolates showed 53 cgMLST strains. Seven of the 53 strains were shared by 2 patients. After institution of universal ESCRE surveillance/isolation there was a significant decline in acquired ESCRE carriage among HSCT recipients. We conclude that vertical transmission of ESCRE organisms through room contamination appears to be uncommon on modern HSCT units. Conversely, our results are consistent with the horizontal spread of ESCRE organisms, probably mediated by intermediate vectors such as personnel or shared equipment. Further studies are needed to better define the magnitude of and risk factors for ESCRE horizontal transfers and the benefits of ESCRE surveillance/isolation.

AbstractObjective:To compare the effects of empiric carbapenems versus cycling cefepime and piperacillin/tazobactam on the rates of vancomycin-resistant Enterococcus(VRE) colonization, bloodstream infections, and outcomes of patients admitted with acute leukemia.Design:Retrospective clinical study with VRE molecular strain typing and gastrointestinal microbiome comparison.Setting:A regional referral center for acute leukemia.Patients:342 consecutive patients admitted with newly diagnosed acute leukemia.Methods:In September 2015, we changed our empiric antibiotic of choice for neutropenic fever from a carbapenem to the cycling regimen. We studied 214 consecutive patients during the carbapenem period and 128 during the cycling period. Surveillance for VRE stool colonization was conducted weekly. Representative stool samples were analyzed for VRE MLST types and changes in the composition and diversity of the fecal microbiota.Results:The change in empiric antibiotics was associated with a significant decrease in VRE colonization (hazard ratio [HR], 0.35; 95% confidence interval [CI], 0.27–0.66), a switch in the dominant VRE MLST types on the unit, and some modifications in the gastrointestinal microbiome. There were no differences in total gram-positive or gram-negative BSIs. During the carbapenem period, we observed higher absolute numbers of Candidaspp and fewer ESBL BSIs, but these did not reach statistical significance. Patients during the carbapenem period had longer lengths of stay and durations of severe neutropenia and 10% higher hospital cost.Conclusions:Carbapenem-sparing empiric antibiotic regimens may have advantages related to VRE ecology, gastrointestinal dysbiosis, duration of neutropenia, cost and length of stay.

OBJECTIVEWhile a direct relation between hospital construction and concomitant infection rates has been clearly established, few data are available regarding the environmental decontamination effects of renovation in which surfaces are replaced and regarding subsequent infection incidence.DESIGNRetrospective clinical study with vancomycin-resistant Enterococcus(VRE) molecular strain typing and environmental cultures.SETTINGA regional referral center for acute leukemia and hematopoietic stem-cell transplantation.PATIENTSOverall, 536 consecutive hospital admissions for newly diagnosed acute leukemia or a first autologous or allogeneic stem-cell transplantation were reviewed.INTERVENTIONDuring 2009–2010, our unit underwent complete remodeling including replacement of all surfaces. We assessed the effects of this construction on the incidence of hospital-acquired VRE colonization before, during, and after the renovation.RESULTSWe observed a sharp decrease in VRE colonization rates (hazard ratio, <0.23; 95% confidence interval, 0.18–0.44; P<.0001) during the first year after the renovation, with a return to near baseline rates thereafter. The known risk factors for VRE colonization appeared to be stable over the study interval. Environmental cultures outside of patient rooms revealed several contaminated areas that are commonly touched by unit personnel. Multilocus sequence typing of VRE isolates that were cryopreserved over the study interval showed that dominant strains prior to construction disappeared and were replaced by other strains after the renovation.CONCLUSIONSUnit reconstruction interrupted endemic transmission of VRE, which resumed with novel strains upon reopening. Contamination of environmental surfaces and shared equipment may play an important role in endemic transmission of VRE.Infect Control Hosp Epidemiol2017;38:1055–1061

ABSTRACTRecent outbreaks of carbapenem-resistant Enterobacteriaceaeinfections associated with duodenoscopes used for endoscopic retrograde cholangiopancreatography have highlighted the challenge of cleaning and high-level disinfection of these instruments. The Food and Drug Administration has suggested that duodenoscope surveillance by microbiological culturing, along with strict adherence to reprocessing protocols, may help reduce the risk of duodenoscope-associated infection transmission. We developed and validated an effective, user-friendly duodenoscope sampling and culture protocol and compared its performance to the interim Centers for Disease Control and Prevention–recommended guidelines. Our protocol resulted in a 65% recovery rate for Gram-negative organisms, demonstrating a 2-fold increased recovery rate compared to the CDC method. The implementation of this protocol may increase the feasibility of duodenoscope surveillance for microbiology laboratories and endoscopy departments.