bluuebunny/crossref_metadata_2025_split huggingface dataset:
492. High Prevalence of Colonization with Carbapenem-Resistant Enterobacteriaceae Among Patients Admitted to Vietnamese Hospitals: Risk Factors and Burden of Disease
Authors: Tran Dien M , Larsson Mattias , Olson Linus , TB Hoang Ngoc , Kien Ngai Le , TK Khu Dung , Nguyen Hung D , Vu Tam V , Trinh Tinh H , Le Thinh Q , TT Phan Phuong , Nguyen Binh G , Pham Nhung H , Mai Bang H , Nguyen Tuan V , Nguyen Phuong T K , Le Nhan D , Huynh Tuan M , Anh Thu Le Thi , Chi Thanh Tran , Berglund Björn , Nilsson Lennart E , Bornefall Elin , Huu Song L , Stig-Inge. Hanberger Hakan 
Published: October 2019

Abstract

Background
Carbapenem-resistant Enterobacteriaceae (CRE) is an increasing problem worldwide, but particularly problematic in low- and middle-income countries (LMIC) due to limitations of resources for surveillance of CRE and infection prevention and control (IPC).

Methods
A point prevalence survey (PPS) with screening for colonization with CRE was conducted on 2233 patients admitted to neonatal, pediatric and adult care at 12 Vietnamese hospitals located in northern, central and southern Vietnam during 2017 and 2018. CRE colonisation was determined by culturing of fecal specimens on selective agar for CRE. Risk factors for CRE colonisation were evaluated. A CRE admission and discharge screening sub-study was conducted among one of the most vulnerable patient groups; infants treated at an 80-bed Neonatal ICU from March throughout June 2017 to assess CRE acquisition, hospital-acquired infection (HAI) and treatment outcome.

Results
A total of 1165 (52%) patients were colonized with CRE, most commonly Klebsiella pneumoniae (n = 805), Escherichia coli (n = 682) and Enterobacter spp. (n = 61). Duration of hospital stay, HAI, intubation, peripheral venous catheter and treatment with a carbapenem were independent risk factors for CRE colonization. The PPS showed that the prevalence of CRE colonization increased on average 4.2% per day and mean CRE colonisation rates increased from 13% on the day of admission to 89% at day 15 of hospital stay. At the NICU CRE colonisation increased from 32% at admission to 87% at discharge, mortality was significantly associated (OR 5·5, P < 0·01) with CRE colonisation and HAI on admission.

Conclusion
These data indicate that there is an epidemic spread of CRE in Vietnamese hospitals with rapid transmission to hospitalized patients. CRE colonization places a major burden on the healthcare system due to the increased risk of HAI caused by CRE and associated increased mortality. This study shows that large-scale epidemiological surveillance of CRE using affordable methods is possible in low- and middle-income countries.

Disclosures
All authors: No reported disclosures.
506. Urinary Catheters Are Associated with Progression from Bacteriuria to Invasive Infections in Patients with Carbapenem-Resistant Enterobacteriaceae, Metropolitan Atlanta, 2011–2017
Authors: Howard-Anderson Jessica , Bower Chris W , Smith Gillian , Elizabeth Sexton Mary , Satola Sarah W , Farley Monica M , Jacob Jesse T 
Published: October 2019

Abstract

Background
Patients with carbapenem-resistant Enterobacteriaceae (CRE) bacteriuria have better outcomes than patients with an invasive CRE infection, but patients with bacteriuria may subsequently develop an invasive infection (“progression”). We sought to evaluate risk factors, particularly urinary catheters, for progression from CRE bacteriuria to an invasive CRE infection within one year.

Methods
We used population-based active surveillance data from the Georgia Emerging Infections Program to identify patients in metropolitan Atlanta with CRE in urine, but not in a concomitant or previous sterile site between August 1, 2011 and July 31, 2017. CRE was defined as an isolate resistant to tested third-generation cephalosporins and a minimum inhibitory concentration of ≥4 µg/mL for meropenem, doripenem or imipenem. We then assessed if these patients developed an invasive CRE infection (positive sterile site culture) with the same organism between one day and one year later. Demographics, culture site, comorbidities, and risk factors were obtained by chart review. Univariable analyses and multivariable logistic regression with progression as the outcome were performed in SAS 9.4.

Results
We identified 551 patients with CRE bacteriuria in 6 years, with an annual incidence of 1.1 cases/100,000 population. Many patients previously resided in long-term care facilities (48%), had a Charlson comorbidity index (CCI) >3 (38%), a central venous catheter (CVC, 34%) or a decubitus ulcer (27%, Table 1). Twenty-five patients (5%) progressed from CRE bacteriuria to an invasive CRE infection within one year (median 34 days). Predictors of progression in univariable analyses included the presence of a urinary catheter (OR 6.4 [95% CI: 1.9–21.6]), decubitus ulcer, CVC or other indwelling device, Klebsiella pneumoniae, black race, CCI >3, and ICU stay after urine culture was obtained (Table 2). In a multivariable analysis, urinary catheter (OR 4.6 [95% CI: 1.3–16.1]) predicted progression as well as K. pneumoniae, CCI >3 and CVC.

Conclusion
Progression from CRE bacteriuria to an invasive CRE infection is rare but clinically significant and is associated with urinary catheters. Future interventions should target urinary catheter removal, where possible, in patients with CRE bacteriuria.

Disclosures
All authors: No reported disclosures.
510. Exposure Investigation Following a Confirmed Case of Candida auris and Multiple Carbapenemase-Producing Carbapenem-Resistant Organisms
Authors: Nicholson Frances , Curless Melanie , Schiffhauer Maggie , Zhang Sean , Simner Patricia , Carroll Karen C , Rock Clare , Maragakis Lisa , Maragakis Lisa 
Published: October 2019

Abstract

Background
Co-infections of Candida auris and carbapenemase-producing carbapenem-resistant Gram-negative organisms (CP-CRO) are an increasing global concern and rarely seen in the United States. We report the case of a 59-year-old male, with recent hospitalization in India, admitted to our facility with C. auris isolated from urine and axilla/groin specimens and CP-CRO from five body sites.

Methods
Travel screening in the emergency department identified a patient at high risk for colonization/infection with multidrug-resistant organisms (MDRO). Contact precautions were initiated. Eight CP-CRO isolates were subsequently identified from clinical and routine surveillance cultures from five separate sites. Of the isolates, seven contained one or more carbapenemase-producing genes detected by Xpert Carba-R assay (Cepheid, Sunnyvale, CA) (Table 1). The microbiology laboratory alerted the infection control department of a presumptive positive C. auris from a clinical urine culture from the same patient. Enhanced mitigation strategies were initiated in regards to cleaning and disinfection.
An exposure investigation was also conducted using a point prevalence approach. Surveillance cultures were obtained from inpatients currently admitted to the same unit as the index patient. Axilla/groin specimens were collected for C. auris testing, and rectal specimens were collected for CP-CRO gene testing (CRE Real-Time PCR).

Results
Eighteen patients in addition to the index patient were hospitalized on the acute medicine unit. One patient refused testing for CP-CRO; therefore, 17 patients were tested for CP-CRO, and 18 patients were tested for C. auris. Neither CP-CRO nor C. auris were recovered from any patient.

Conclusion
A patient co-infected with C. auris and multiple CP-CRO was identified by clinical and routine surveillance cultures at Johns Hopkins Hospital. Travel screening allowed proactive isolation upon presentation. Enhanced infection control measures were implemented and a point prevalence surveillance study was conducted on the general acute care medicine inpatient unit. No transmission of either C. auris or CP-CRO was detected, likely due in part to rapid identification and strict infection control measures.

Disclosures
All authors: No reported disclosures.
521. Comparative In Vitro Activity of Meropenem/Vaborbactam and Meropenem Against a Collection of Real-World Clinical Isolates of Pseudomonas aeruginosa
Authors: Patel Twisha S , Kaye Keith S , Krishnan Jay , Marshall Vince , Mills John , Albin Owen , Young Carol , Smith Aaron , Lephart Paul , M. Pogue Jason 
Published: October 2019

Abstract

Background
Meropenem/vaborbactam (MV) is a carbapenem and boronic acid–based β-lactamase inhibitor combination product with potent in vitro activity against Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae. As carbapenem resistance in Pseudomonas aeruginosa (PSA) is primarily driven by porin mutations, efflux pumps, or infrequently by metallo-β-lactamases, vaborbactam is not expected to improve the in vitro activity of meropenem (MEM) against this pathogen. However, limited data currently exists assessing the comparative in vitro activity of MEM and MV. The purpose of this study was to compare the in vitro activity of MV and MEM against a large real-world sample of clinical isolates of PSA where both MV and MEM are routinely tested on all isolates.

Methods
All cultures from patient infections with PSA from May 2018 to February 2019 at Michigan Medicine were included. Minimum inhibitory concentrations (MICs) were determined using TREK broth microdilution panels and isolates were considered susceptible to MV if the MIC was ≤4 mg/L and MEM if the MIC was ≤2 mg/L.

Results
A total of 2,967 isolates of PSA from clinical specimens were included. 80.5% of isolates were susceptible to MEM (MIC50 ≤1 mg/L and MIC90 8 mg/L, range ≤1 to >32 mg/L) at a breakpoint of ≤2 mg/L and 86.3% at a breakpoint of ≤4 mg/L; whereas 90.8% of isolates were susceptible to MV (MIC50 ≤1 mg/L and MIC90 4 mg/L, range ≤1 to >8 mg/L). Of those displaying MEM MIC >2 mg/L, 53% (n = 308) were susceptible to MV. Of those displaying MEM MIC >4 mg/L, 33.7% (n = 137) were susceptible to MV. Although the majority of MIC discordances in MEM-R/MV-S isolates were 1–2 doubling dilutions, 52 (38%) isolates had their meropenem MIC decreased ≥3 doubling dilutions by the addition of vaborbactam suggesting significant inhibitory activity (Table 1).

Conclusion
We found a surprising number of PSA isolates with discordant MV and MEM susceptibility at Michigan Medicine. Further exploration of mechanisms of meropenem resistance in these isolates is warranted.

Disclosures
All authors: No reported disclosures.
540. The Impact of Diet and Oral Hygiene on the Risk of Multidrug-Resistant Organism Carriage in the Mouth and Gut
Authors: Kates Ashley , Watson Lauren , Mares Julie , Christensen Krista , Kalan Lindsay , Malecki Kristen , Peppard Paul , Sethi Ajay , Safdar Nasia 
Published: October 2019

Abstract

Background
Little is known about the relationship between oral hygiene and multidrug-resistant organism in the mouth and gut. We aimed to assess the relationship of oral hygiene and diet with multidrug-resistant organism (MDRO) carriage in the oral cavity and gut.

Methods
Participants were adults over age 18 from the 2016–2017 Survey of the Health of Wisconsin (SHOW) and its ancillary Wisconsin Microbiome Study. SHOW surveys residents of Wisconsin, collecting health determinants including a food frequency questionnaire, oral health, as well as biologic specimens. MDROs were defined as the presence of methicillin-resistant Staphylococcus aureus, Vancomycin-resistant Enterococcus, and Fluoroquinolone-resistant Gram-negative bacteria identified via culture from saliva, oral swabs, and stool samples. Statistical analysis was performed in R v3.5.1. Univariate analyses were conducted for all variables in the data set. Any variable with a P-value < 0.2 in the univariate analysis was considered for the logistic regression. Logistic regression using the glm function was done modeling MDRO carriage in either the saliva, oral swab, saliva and oral samples combined, and stool against diet, oral health, and known confounders.

Results
876 participants were included in the dataset with all 876 providing oral and stool samples and 784 providing saliva samples. Thirty-three patients were MDRO positive in the saliva (4.2%), 36 were positive in the oral swabs (4.1%), 55 were positive in either the saliva or oral swabs (6.3%), and 103 were positive in the stool (11.8%). In the logistic regression, consumption of whole grains was significantly associated with reduced MDRO carriage in the saliva (P = 0.046) and saliva and oral swab combined (P = 0.036) data sets (Table 1).

Conclusion
Consuming more whole grains was associated with a lower prevalence of MDRO carriage in the oral cavity. Higher levels of sugar consumption were associated with a higher prevalence of MDRO in the gut. Oral hygiene was not found to be associated with MDRO colonization in the mouth and a higher prevalence in the gut in this cross-sectional study. This may be due to over-reporting of hygiene practices by participants. Being positive for an MDRO in the oral cavity significantly increased the risk of MDRO carriage in the gut.

Disclosures
All authors: No reported disclosures.
549. First Report for Emergence of Chromosomal Borne Colistin Resistance Gene mcr-1 in a Clinical Acinetobacter Baumannii Isolates from India
Authors: RAHMAN MOHIBUR , Ahmad Saheem 
Published: October 2019

Abstract

Background
Efficacy of Colistin the last line agent against infections due to multidrug-resistant (MDR) gram-negative pathogens, has been challenged when Liu et al. reported a plasmid-mediated gene, mcr-1, in 2015. Thereby this plasmid-borne mcr has been reported in bacterial isolates worldwide taken from humans, animals, farms, foods, and the environment. The present work invesitigate the mcr gene among clinical isolates of Acinetobacter Baumannii at our tertiary referral hospital of India.

Methods
The study was conducted at Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India. MIC values for 100 consecutive non-duplicate MDR isolates of Acinetobacter were checked for Colistin. PCR amplification of mcr gene was performed followed by sequencing of the amplicons. Clinical features of patients infected with mcr positive isolates were unveiled. Clonal relatedness of these isolates was investigated by Pulsed-field gel electrophoresis (PFGE). The mcr-1 localization was checked by conjugation followed by PFGE southern hybridization.

Results
20/100 (20%) isolates were colistin resistant with having MIC Values of more than 8≤ µg/mL. The 20 colistin resistances isolates were PCR positive for mcr-1 and had been assigned EMBL/GeneBank nucleotide accession numbers MH730099-MH730118. Oher antibiotic resistance gene like ESBL, NDM-1, VIM, and 16s rRNA methyl transferases like Arm A, rmtC, rmt F were also found in these isolates. Majority of these patients recovered from the infection (65%) after proper antibiotic therapy.The ISApl1 transposable elements were not detected in these isolates. These isolates were found clonally unrelated when analyze by pulsed-field gel electrophoresis. The conjugation attempt to transfer mcr-1 to recipient’s E. coli J53 failed, Southern hybridization showed that mcr-1 was found located on chromosome in multiple copies.

Conclusion
This is the first case of mcr-1 in a human clinical isolate in Acinetobacter Baumnnii from India. These findings highlight the vertical transferability of colistin resistance by mcr-1 gene in Acinetobacter Baumnnii with the association of known some unknown insertion sequence located on chromosome. Strategies required to contain their spread and evolution of such genes.

Disclosures
All authors: No reported disclosures.
550. Carbapenem--Resistant E. coli and A. baumannii Among Catheter-Related Blood Stream Infection Patients in Egyptian ICUs
Authors: Elmanakhly Arwa R , Kholy Amani 
Published: October 2019

Abstract

Background
The spreading of E. coli and A. baumannii in hospitals is a growing concern due to increased resistance to carbapenems and Fluoroquinolones. The present study aimed to specifically evaluate the presence of mutations in the gyrA and parC genes in Egyptian ICU and their correlation with carbapenem-resistant genes E. coli and A. baumannii isolates from patients in 4 tertiary care hospital in Egypt.

Methods
A total of 120 A. baumannii and E. coli clinical isolates were isolated from ICU patients in 4 tertiary hospitals in Egypt. The bacterial isolates were identified by VITEK-2 (Bio Merieux, France). Antimicrobial susceptibility testing was performed according to CLSI guidelines. Phenotypic detection of carbapenemase activity was done by carba-NP test, followed by molecular identification of carbapenemase encoding genes blaNDM, blaOXA-48 and blaKPC by multiplex PCR. The quinolone resistance-determining regions (QRDRs) of gyrA and parC genes were amplified by singleplex PCR followed by reverse and forward sequencing to detect the gene mutation. The DNA sequences were compared with the sequences of wild type of these genes available in GenBank database. Then, the obtained DNA sequences and their amino acid sequences were analyzed using bioinformatics tools.

Results
All isolates showed a high level of resistance among tested antimicrobial agents (cephalosporins, aminoglycosides, carbapenems, penicillins) that ranged from 36% to 100%. Carba-NP detected 43.59% of the carbapenem-resistant isolates. Multiplex PCR detected that 17.95%, 46.15% and 2.56% of isolates were harboring blaKPC, blaNDM and blaOXA-48 respectively. PCR and sequencing technique showed combined gene mutation in 8 carbapenem-resistant E. coli and A. baumannii isolates. The specific substitutions observed in gyrA were Cys173Arg, Cys174 Gly, Asp80Val, Tyr178ASP, Tyr84Gly, Glu85Lys, Ser172Leu and Asp176Asn. While, the specific substitutions observed in parC were point mutation 62 Arg, Phe60Leu, Ils66Val, Gln76Lys. Point mutation 62 Arg was observed in two A. baumannii isolates, whereas Ser172Leu mutation was observed in two E. coli isolates.

Conclusion
The presence of carbapenem resistance genes in combination with single and multiple mutations in QRDR causes the presence of highly resistant E. coli and A. baumannii isolates in the Egyptian hospitals.

Disclosures
All authors: No reported disclosures.
557. Impact of Heavy Metal Exposure in the Transcriptional Response of Methicillin--Resistant Staphylococcus aureus (MRSA)-USA300 Latin-American Variant (USA300-LV)
Authors: Echeverri Aura M , Rincon Sandra , Solano Sebastian , Rios Rafael , Carvajal Lina P , Arias Cesar A , Diaz Lorena , Reyes Jinnethe 
Published: October 2019

Abstract

Background
USA 300-LV is the predominant MRSA clone in Colombia and contains a genomic island designated “COMER” with genes for copper (Cu) and mercury (Hg) resistance. HM environmental contamination is a serious threat to public health in Colombia and could also influence the selection and evolution of HM resistance genes in MRSA. Here, we investigate the global transcriptomic responses of USA300-LV after exposure to HM under the hypothesis that USA300-LV strains are highly capable of sustaining higher HM concentrations

Methods
We performed comparative RNAseq experiments in USA300-LV clinical strain (CA-MRSA12). Total RNA was isolated in exponential phase in the absence and presence of sub-inhibitory concentrations of Cu and Hg (3 replicates). cDNA libraries were prepared and sequenced on an Illumina platform. Differentially expressed genes (DEG) were calculated by DeSeq2 (p-adjusted value ˂ 0.01) and results on 19 selected genes were confirmed by qRT-PCR.

Results
US300-LV exhibited a larger number of differentially expressed genes when exposed to Hg (n = 114) compared with Cu treatment (n = 16). The most common functional groups of genes upregulated after Hg exposure included those involved in amino acid metabolism (n = 18). In contrast, 45 genes were downregulated after Hg exposure, mostly associated to host immune system defense (n = 11). qRT-PCR confirmed that the most upregulated genes were those involved in murein hydrolase activity, Hg resistance and the transcriptional regulator Cro/CI. Of 9 genes that were downregulated, functional groups included ype VII secretion system, immune modulators and leucocidins. Copper treatment resulted in only 12 genes that were upregulated including those in the COMER element (n = 6), aminoacid metabolism (n = 3), ROS response (n = 1), host immune system defense (n = 1) and unknown function (n = 1). Downregulated genes were those associated to host immune system defense (n = 2), energy generation (n = 1) and unknown function (n = 1).

Conclusion
Differential adaptive responses after exposure to HM in USA300-LV suggest a role in the evolution of antimicrobial resistance and successful spread in the region. Metabolic adaptations involving amino acid metabolism seem to play a role in the evolution of HM resistance in MRSA.

Disclosures
All authors: No reported disclosures.
574. Reporting of Vancomycin-Resistant Enterococcus Bacteremia among National Healthcare Safety Network Acute Care Hospitals
Authors: Tanwar Sukarma S S , Lastinger Lindsey , Bell Jeneita , Bagchi Suparna , Allen-Bridson Katherine , Dudeck Margaret , Edwards Jonathan R 
Published: October 2019

Abstract

Background
The National Healthcare Safety Network’s (NHSN’s) Multidrug-resistant Organism/Clostridioides difficile (MDRO/CDI) Module serves as a surveillance platform for tracking antibiotic-resistant laboratory-identified (LabID) organisms. LabID event surveillance, which does not require submission of clinical data to NHSN, provides proxy measures for MDRO burden. While surveillance of some organisms is federally mandated, these requirements do not extend to vancomycin-resistant Enterococcus (VRE). We sought to describe the extent of acute care hospital (ACH) participation in NHSN VRE surveillance and identify facility-level factors associated with VRE bacteremia. These could explain differences in VRE incidence and be used in preparation for a national risk-adjusted benchmark.

Methods
ACHs that reported at least one month of facility-wide inpatient (FacWideIN) VRE bacteremia LabID Event data to NHSN in 2017 were included in the analysis. LabID events were categorized as healthcare facility-onset (HO), defined as a laboratory result for a specimen collected ≥4 days after admission, or community-onset (CO), defined as a specimen collected < 4 days after admission. Monthly patient day and admission denominators were used to calculate FacWideIN HO incidence and CO prevalence rates. Univariate analyses were performed on facility-level factors from NHSN’s annual hospital survey to assess their relationship with HO VRE bacteremia.

Results
A total of 544 HO VRE bacteremia events were reported by 498 hospitals in 37 states. About 67% of reporting hospitals were located in California. The national rate of HO VRE bacteremia was 0.27 per 10,000 patient-days and the CO VRE bacteremia rate was 0.58 per 10,000 admissions. Major medical school affiliation, hospital type, larger number of beds and ICU beds, longer average length of stay and the presence of an oncology unit were significantly associated with HO VRE bacteremia (Table 1).

Conclusion
Based on the VRE data reported to NHSN, certain facility-level factors may contribute to a higher incidence of HO VRE bacteremia. Future analyses can allow us to determine whether these factors are independently associated with VRE. Risk-adjusted surveillance data can help guide facilities and states to compare their burden of VRE to a national benchmark.

Disclosures
All authors: No reported disclosures.