bluuebunny/crossref_metadata_2025_split huggingface dataset:
1168. Role of Extended-Spectrum Cephalosporin-Resistance in Recurrent Enterobacteriaceae Urinary Tract Infections
Authors: Anesi Judith , Lautenbach Ebbing , Nachamkin Irving , Garrigan Charles , Bilker Warren , Omorogbe Jacqueline , Dankwa Lois , Wheeler Mary K , Tolomeo Pam , Han Jennifer ,   CDC Prevention Epicenters
Published: November 2018

Abstract

Background
Recent data have shown an increase in bacterial resistance to first-line antibiotics used to treat community-onset urinary tract infections (UTIs). A better understanding of the clinical outcomes associated with drug-resistant UTIs in the community is needed. We sought to determine the association between community-onset extended-spectrum cephalosporin-resistant (ESC-R) Enterobacteriaceae (EB) UTI and the risk for recurrent UTI.

Methods
A retrospective cohort study was performed. All patients presenting to the Emergency Departments (EDs) or outpatient practices with EB UTIs between 2010 and 2013 were included. Exposed patients had ESC-R EB UTIs. Unexposed patients had ESC-susceptible EB UTIs and were matched to exposed subjects 1:1 on study year. Multivariable Cox proportional hazard regression analyses were performed to evaluate the association between ESC-R EB UTI and time to recurrent UTI within 12 months. Patients were censored at the time of first recurrent UTI or at the end of follow-up.

Results
A total of 302 patients with an index community-onset EB UTI were included, with 151 exposed and unexposed. Within 12 months of the index UTI, 163 (54%) patients experienced a recurrent UTI. The median time to recurrence was 69 days (interquartile range 25–183 days). On multivariable analyses, a UTI due to an ESC-R EB was associated with an increased hazard of recurrent UTI (hazard ratio [HR] 1.39, 95% confidence interval [CI] 1.01–1.91, P = 0.04). Other variables that were independently associated with an increased hazard of recurrent UTI included a history of UTI in the 6 months prior to the index UTI (HR 1.59, 95% CI 1.17–2.15, P &lt; 0.01) and presence of a urinary catheter at the time of the index UTI diagnosis (HR 1.59, 95% CI 1.06–2.38, P = 0.03).

Conclusion
Community-onset UTI due to an ESC-R EB organism is associated with a significantly increased hazard of recurrent UTI within 12 months even after adjusting for baseline factors that predispose patients to UTI recurrence. This study raises the question of whether patients with an ESC-R EB organism may require modified treatment regimens. Further study is needed to better elucidate the cause of recurrence among these patients.

Disclosures
All authors: No reported disclosures.
1170. Applying Machine Learning Algorithms to Predict Multi-Drug-Resistant Bacterial Infections From Prior Drug Exposure
Authors: Lendrum Elizabeth , Haslam David , Ambroggio Lilliam 
Published: November 2018

Abstract

Background
Multi-drug-resistant (MDR) infection in the acute care setting prolongs hospital stay and causes high mortality, especially in the pediatric population. Being able to predict MDR infection risk upon or during admission could help prevent and reduce morbidity and mortality in children requiring acute care in the future. This study aimed to develop and validate a predictive model for MDR infection in the pediatric population using machine learning (ML) analysis.

Methods
The study population included hospitalized pediatric patients diagnosed with MDR infection between January 1, 2010 and March 8, 2018. All positive cultures during that period were coded as growing either an MDR or non-MDR organism. ML was performed with random forest (RF) analysis to determine whether hospital drug exposure in the 90 days prior to culture was able to accurately classify cultures as positive for an MDR or non-MDR organism.

Results
During the study period, 7,551 positive cultures were defined as MDR out of a total of 26,913 cultures (28% of all positive cultures). When all cultures were included in the analysis, RF was modestly successful at classifying MDR vs. non-MDR organisms. Significant improvements in classification accuracy were obtained by subdividing cultures based on growth of individual species. RF was able to classify MDR Enterococcus with accuracy = 0.87, positive predictive value of 0.81, and negative predictive value of 0.88. Surprisingly, exposure to many nonantibiotic drugs were important in predicting antibiotic resistance, indicating either that these drugs altered risk directly, or were correlated with MDR risk indirectly.

Conclusion
Drugs without known antimicrobial activity were important predictors of MDR status. Nonantimicrobial drug exposure may be a marker for disease types or therapeutic interventions that place patients at higher risk of MDR infection. Monitoring antimicrobial and nonantimicrobial drug exposure may accurately identify patients at highest risk of MDR infection.

Disclosures
All authors: No reported disclosures.
1175. Clinical and Microbiological Features of Klebsiella pneumoniae Liver Abscess Caused by Multidrug-Resistant Strains
Authors: Lin Yi-Tsung , Cheng Yi-Hsiang , Chuang Chien 
Published: November 2018

Abstract

Background
The endemic Klebsiella pneumoniae liver abscess (KPLA) in East Asian countries are usually caused by hypervirulent strains. These hypervirulent strains are usually susceptible to commonly used antibiotics, aside from their intrinsic resistance to ampicillin. However, hypervirulent K. pneumonaie strains with multidrug-resistant (MDR) phenotype has been reported recently. We aim to investigate clinical and microbiological features of KPLA caused by MDR-resistant strains, and the evolution of drug-resistance in the resistant strain causing recurrent KPLA.

Methods
Patients with KPLA were retrospectively identified at Taipei Veterans General Hospital during January 2013 to February 2018. Capsular genotypes were analyzed in all K. pneumoniae isolates. Antimicrobial-resistant mechanisms were determined for MDR isolates. Pulse-field gel electrophoresis (PFGE), conjugation experiment, and in vivo mice lethality were determined on the strains from a patient with recurrent infection.

Results
During the study period, a total of 211 patients with KPLA, and five patients with recurrence were identified. Most of K. pneumoniae isolates (n = 175, 83.3%) belonged to capsular type K1/K2/K5/K20/K54/K57. Nineteen MDR strains were identified and 15 of them had virulent capsular types (K1 = 7, K2 = 5, K5 = 2, K54 = 1). The major resistance mechanisms of these MDR strains involved the presence of β-lactamases and the overexpression of efflux pumps. The in-hospital mortality of KPLA caused by MDR strains was not significantly higher than wild-type stains (10.53% vs. 4.69%, P = 0.275). In a case with recurrent KPLA, the recurrent capsular type K1 strain (TVGHKP2611) with blaSHV-12 was genetically identical to the primary wild-type resistance strain (TVGHKP2329) by PFGE. The SHV-12-carrying plasmid from TVGHKP2611 was successfully conjugated to Eschericia coli J53. TVGHKP2611 retained high virulence similar to TVGHKP2329 in mice lethality study (median lethal dose &lt; 500 CFU) despite carrying the resistance determinant.

Conclusion
MDR K. pneumoniae strains belonging to virulent capsular types have emerged in KPLA. One SHV-12 producing capsular K1 strain causing recurrent KPLA retained its high virulence, which signals this highly pathogenic and resistant strain could be a major concern in the future.

Disclosures
All authors: No reported disclosures.
1184. Resistance Patterns and Susceptibility Analysis of Klebsiella pneumoniae Infections in Service Members Who Sustained Trauma in Iraq and Afghanistan
Authors: Kiley John , Mende Katrin , Kaiser Susan J , Carson Leigh , Lu Dan Z , Merritt Teresa , Whitman Timothy , Petfield Joseph L , Tribble David R , Blyth Dana M 
Published: November 2018

Abstract

Background
Klebsiella pneumoniae was the third most common species of multidrug-resistant (MDR) Gram-negative organism in military trauma patients injured in Iraq and Afghanistan (2009–2014). This study aims to characterize the antimicrobial susceptibility and resistance patterns of K. pneumoniae isolates in these patients.

Methods
All infecting K. pneumoniae isolates (IKpI) archived by the Trauma Infectious Disease Outcomes Study (TIDOS) and 96 colonizing isolates (CKpI) from groin swabs were included (6/09-12/14). All CKpI linked with IKpI were included; the remainder to total 50 MDR and 46 non-MDR CKpI were chosen randomly. Antimicrobial identification and susceptibilities were determined by CLSI criteria using the BD Phoenix Automated Microbiology System. MDR was defined as either resistance to ≥3 classes of aminoglycosides, β-lactams, carbapenems, and/or fluoroquinolones or production of an ESBL or KPC.

Results
Of 588 K. pneumoniae archived isolates, 237 isolates were included in the analysis (141 IKpI and 96 CKpI). IKpI sources were 40% wound, 22% respiratory, 20% blood, 9% urine, and 9% other. Antibiotic susceptibilities for IKpI were: cefazolin (CFZ) 20%, ceftriaxone 30%, levofloxacin 62%, piperacillin–tazobactam (PTZ) 41%, meropenem 96%, and amikacin 89%. MDR IKpI and CKpI were more likely to have had prior fluoroquinolone (82% vs. 18%, P &lt; 0.01) or anti-pseudomonal penicillin (53% vs. 47%, P &lt; 0.01) exposure. Seventeen patients had CKpI cultured at a median of 5 days (IQR 2–17) before a subsequent IKpI with 11 (65%) having MDR CKpI. All IKpI isolated after MDR CKpI were also MDR. Among IKpI recovered after non-MDR CKpI, new resistance was noted in 1 IKpI to gentamicin (200 days post-CKpI), 1 IKpI to ertapenem (7 days post-CKpI), two IKpI to CFZ (10 days and 17 days, respectively), and 1 IKpI to PTZ (19 days post-CKpI). Serial isolates of IKpI had similar MDR status (63% initial IKpI were MDR, whereas 76% of subsequent IKpI were MDR).

Conclusion
K. pneumoniae isolates in military trauma patients from Iraq and Afghanistan had challenging resistance patterns. Prior exposure to fluoroquinolones and anti-pseudomonal penicillins were associated with MDR K. pneumoniae isolation. MDR status of CKpI predicted subsequent IKpI MDR status.

Disclosures
All authors: No reported disclosures.
1185. Impact of Bloodstream Infections Caused by Multidrug-resistant Organisms on Performance Status: A KARS-Net Study
Authors: Huh Kyungmin , Chung Doo Ryeon , Ko Jae-Hoon , Ha Young Eun , Kim Si-Ho , Oh Suhyun , Jang Sukbin , Mun Seokjun , Huh Hee Jae , Lee Nam Yong , Cho Sun Young , Kang Cheol-In , Peck Kyong Ran , Song Jae-Hoon ,   the Korean Antimicrobial Resistance Surveillance Network (KARS-Net) Investigators
Published: November 2018

Abstract

Background
Infections caused by multidrug-resistant (MDR) organisms are associated with poorer clinical outcomes and higher economic burden. However, there has been limited data on the impact of MDR infection on the performance status of patients.

Methods
Patients with bloodstream infections by S. aureus, E. faecium, E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii have been identified prospectively as a part of a multicenter nationwide surveillance for antimicrobial resistance. Medical records of the patients enrolled from July 2015 through December 2016 were reviewed for demographic, clinical, microbiologic characteristics, and patient outcome. MDR was defined as MRSA, VRE, and nonsusceptibility to one or more agents in three or more different classes of antibiotics for Gram-negative bacteria. Performance status was evaluated by Eastern Cooperative Oncology Group (ECOG) Performance Status before admission and at discharge. Primary outcome was any decline in ECOG at discharge. Multiple logistic regression was used to identify independent risk factors for ECOG decline.

Results
A total of 19 hospitals participated to the network. The numbers of subjects were 410 for S. aureus, 392 for E. faecium, 708 for E. coli and K. pneumoniae, and 678 for P. aeruginosa and A. baumannii. In univariate analysis, bacteremia by MDR organisms was associated with ECOG decline only in patients with P. aeruginosa (18.4% vs. 10.3%, OR 1.962, 95% CI 1.132–3.399) and A. baumannii (27.6% vs. 11.8%, OR 2.834, 95% CI 1.328–6.045) infections. Patients with MDR K. pneumoniae infection had lower risk of ECOG decline (6.6% vs. 15.8%, OR 0.378, 95% CI 0.183–0.780). Multivariable analysis also showed that infection by MDR organism was independently associated with ECOG decline in patients with P. aeruginosa or A. baumannii infections (OR 2.068, 95% CI 1.478–2.895), but not with other MDR organisms. Comorbidities and initial ECOG showed higher effect size in patients with S. aureus and E. faecium infections.

Conclusion
In this large multicenter nationwide study, bloodstream infections caused by MDR P. aeruginosa and A. baumannii were associated with higher risk of decline in performance status at discharge. MDR status did not show association in infections by other species.

Disclosures
All authors: No reported disclosures.
1204. The MDR Upon Admission Score for Shortening Time to Initiation of Appropriate Antimicrobial Therapy in the Era of Widespread Resistance to Antimicrobials
Authors: Chedid Khalil , Zilberman-Itskovich Shani , Shorbaje Akram , Martin Emily T , Lazarovitch Tsilia , Zaidenstein Ronit , Dadon Mor , Saadon Hodaya , Maya Tal , Marchaim Dror 
Published: November 2018

Abstract

Background
Multi-drug-resistant organisms (MDRO) pose a growing burden, including in non-hospital settings. Delay in initiation of appropriate antimicrobial therapy (DAAT) upon admission to an acute care hospital is common and is associated with worse outcomes. The aim of this study was to develop a prediction score for MDRO infection upon admission, in order to improve patients’ outcomes and avoid misuse of broad-spectrum antimicrobials.

Methods
A retrospective case–control analysis was conducted at Assaf Harofeh Medical Center, Israel, comparing adult patients with MDRO infections diagnosed in the first 48 hours of hospitalization to patients presenting with non-MDRO sepsis (i.e., patients with microbiologically confirmed non-MDRO infection, or patients with non-microbiologically confirmed sepsis). MDROs were determined by clinical laboratory testing. Patients were identified over four consecutive months (August–December 2016). A multivariable logistic regression of predictors for MDRO infection upon admission was used to develop the prediction score.

Results
Ninety-five of 818 total patients (11.6%) had MDRO infection. The final score included 10 parameters: (1) home therapy (IV therapy, wound care, or specialized nursing care, 16 points), (2) routine (at least weekly) outpatient clinic visits in the past 3 months (15 points), (3) history (2 years) of past MDRO colonization (14 points), (4) any antibiotics in the preceding 3 months (12 points), (5) invasive procedure in the past 6 months (11 points), (6) elderly (≥65 years old, 10 points), (7) hemiplegia or paraplegia (8 points), (8) resident of long-term care facility (7 points), (9) severe sepsis (i.e., severe sepsis, septic shock, or multi-organ failure, 6 points), and (10) acute kidney injury (5 points). A cutoff of ≥24 points had a sensitivity of 90%, a specificity of 73% and an ROC AUC = 0.88 (figure).

Conclusion
This study presents the development of a new prediction score for MDRO infection upon admission, based on parameters that could easily be extracted at bedside for patients admitted with sepsis. A future prospective interventional study is needed in order to validate the score, captured at bedside electronically, in terms of improving patients’ outcomes.

Disclosures
All authors: No reported disclosures.
1205. Emergence of Carbapenemase Producing Enterobacteriaceae in South Central Ontario, Canada
Authors: Zhong Zoe , Faheem Amna , Farooqi Lubna , Armstrong Irene , Borgundvaag Emily , Coleman Brenda , Green Karen , Jayasinghe Kithsiri , Johnstone Jennie , Katz Kevin , Kohler Philipp , Li Angel , Melano Roberto , Muller Matthew , Nayani Sarah , Patel Samir , Paterson Aimee , Poutanen Susan , Rebbapragada Anu , Richardson David , Sarabia Alicia , Shafinaz Shumona , Simor Andrew E , Willey Barbara , Wisely Laura , Mcgeer Allison ,   Toronton Invasive Bacterial Diseases Network
Published: November 2018

Abstract

Background
The spread of CPE is an increasing global threat to patient safety. We describe the introduction and evolution of CPE in south-central Ontario, Canada.

Methods
The Toronto Invasive Bacterial Diseases Network has performed population based surveillance for CPE in metropolitan Toronto and Peel region from first identified isolates in 2007. All laboratories test/refer all carbapenem non-susceptible Enterobacterial isolates for PCR testing for carbapenemases. Demographic and medical data and travel history are collected from chart review and patient/physician interview.

Results
Since 2007, 659 patients have been identified as colonized/infected with CPE; 362, 57%) have at least one clinical isolate. Annual incidence has increased from 0 in 2006 to 1.3 per 100,000 in 2016/17 (Figure 1). First bacteremia occurred in 2010, the incidence in 2017 was 0.14 per 100,000 population. 388 (59%) patients were male, median age was 70 years (range 3 months–100 years). Most common genes among first isolates were NDM (306, 46%), OX48 (149, 23%), KPC (122, 19%). Most common species were K. pneumoniae (268, 41%) and E. coli (259, 39%). Over time, second species/same gene were identified in 113 (16%) patients. In addition, 34/xxx patients with isolates with NDM and/or OXA-48 subsequently had a second isolate with a different gene/gene combination. Of 518 patients whose travel and hospitalization history are available, patients with VIM were less likely than other patients to have a foreign hospitalization or travel history (9/28 vs. 341/490, P &lt; 0.0001). Patients with KPC were more likely to have a hospitalization history outside Canada and the Indian subcontinent (25/70, 36%), in Canada (47/164,29%) than to have no hospitalization in the last year (13/93, 14%), or a history of hospitalization in the Indian subcontinent (2/191, 1%) (P &lt; 0.001). The number of incident patients with different hospitalization and travel history over time is shown in Figure 2.

Conclusion
CPE is increasingly recognized in southern Ontario, both in patients with a history of exposure in healthcare in other countries, and to healthcare in Canada. Intensification of control programs is urgently needed.

Disclosures
S. Poutanen, MERCK: Scientific Advisor, Speaker honorarium. COPAN: Speaker(but not part of a bureau), Travel reimbursement. Accelerate Diagnostics: Investigator, Research support. Bio-Rad: Investigator, Research support. bioMérieux: Investigator, Research support.
1206. Risk Factors of Antibiotic Resistance in E. coli Isolated from the MAL-ED Birth Cohort Study in Rural Tanzania
Authors: Fleece Molly , Nshama Rosemary , Walongo Thomas , Gratz Jean , Platts-Mills James , Mduma Esto , Houpt Eric 
Published: November 2018

Abstract

Background
The emergence and spread of antimicrobial resistance is a serious global public health crisis. Drug-resistant Gram-negative bacteria, like Escherichia coli, are particularly concerning given their significant morbidity and mortality. Despite the increasing prevalence of drug-resistant Gram-negative bacteria worldwide, there are significant knowledge gaps in low resource countries. We aimed to characterize the prevalence, phenotypes, and risk factors of drug-resistant E. coli carriage in children up to age 5 from stool collected in the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) birth cohort study in rural Tanzania.

Methods
Two hundred sixty-two children were enrolled in the MAL-ED Tanzania site. We randomly selected 100 children who had E. coli specimens archived every 6 months through 60 months. Up to five lactose-fermenting colonies were selected from growth on MacConkey agar. Drug susceptibility testing of 18 antibiotics was performed by disk diffusion. CLSI interpretive criteria were used for determination of resistance. Generalized estimating equations were used to create a multivariate Poisson regression model for drug resistance risk factors.

Results
Eight hundred twenty-three E. coli specimens were available for testing. The highest rates of resistance were to ampicillin, cefazolin, and cotrimoxazole, respectively. No carbapenem resistance was found. 1.8% met criteria for extended-spectrum β-lactamase production based on combination disk testing. 696 (84.6%) specimens met criteria for multi-drug resistance (nonsusceptible to at least 1 drug in at least three drug categories). In terms of dynamic risk factors, there was no association between antibiotic use or episodes of diarrhea and antibiotic resistance. For static risk factors, there was an association between higher income and increased antibiotic resistance.

Conclusion
Antibiotic resistance carriage is an under recognized problem in this setting. Resistance rates at 6 months of age are higher than expected, with surprisingly little variance explained by individual-level risk factors for resistance in this community.

Disclosures
All authors: No reported disclosures.
1209. Expanding an Economic Evaluation of the Veterans Affairs Initiative to Prevent Methicillin-Resistant Staphylococcus aureus Infections to Include Prevention of Gram-Negative Bacteria
Authors: Nelson Richard E , Goto Michihiko , Samore Matthew , Jones Makoto , Stevens Vanessa , Evans Martin , Schweizer Marin , Perencevich Eli , Rubin Michael 
Published: November 2018

Abstract

Background
In October 2007, the Department of Veterans Affairs (VA) launched the National MRSA Prevention Initiative, a nationwide effort to reduce MRSA transmission through (1) universal screening, (2) contact isolation for MRSA+ patients, (3) institutional culture change that “infection prevention is everyone’s business,” (4) emphasis on hand hygiene, and (5) increased infection control resources. While the initiative focused on MRSA, recent evidence suggests that it also led to a significant decrease in hospital-onset (HO) Gram-negative rod (GNR) bacteremia. The objective of this analysis was to evaluate the cost-effectiveness and the budget impact of the initiative taking into account both MRSA and GNR infections.

Methods
We developed an economic model using published data on the rate of MRSA HAIs and HO-GNR bacteremia in the VA from October 2007 to September 2015, estimates of the attributable cost and mortality of these infections, and the costs associated with the intervention obtained through a microcosting approach. We explored several different assumptions for the rate of infections that would have occurred if the initiative had not been implemented. Effectiveness was measured in life-years (LYs) gained.

Results
We found that during fiscal years 2008–2015, the initiative resulted in an estimated 4,761–9,236 fewer MRSA HAIs and 1,447–2,159 fewer HO-GNR bacteremia. The initiative itself was estimated to cost $206 million over this 8-year period while the cost savings from prevented MRSA HAIs ranged from $75–165 million and from prevented HO-GNR bacteremia ranged from $42–62 million. The incremental cost-effectiveness of the initiative ranged from $12,146–$46,500/LY when just including MRSA HAIs and from $7,945–$24,387/LY when including HO-GNR bacteremia. The overall impact on the VA’s budget ranged from $200–$334 million.

Conclusion
An MRSA surveillance and prevention strategy in VA may have prevented a substantial number of MRSA and GNR infections. The savings associated with the prevented infections helped to offset some but not all of the cost of the initiative. Economic evaluations of these interventions can help decision makers understand the trade offs between increased cost and improved health that can come from such interventions.

Disclosures
All authors: No reported disclosures.