bluuebunny/crossref_metadata_2025 huggingface dataset:
1761. Effect of Carbapenem-Resistant Enterobacteriaceae (CRE) Surveillance Case Definition Change on CRE Epidemiology—Selected US Sites, 2015–2016
Authors: Duffy Nadezhda , Bulens Sandra N , Reses Hannah , Karlsson Maria S , Ansari Uzma , Bamberg Wendy , Janelle Sarah J , Jacob Jesse T , Bower Chris , Wilson Lucy E , Vaeth Elisabeth , Lynfield Ruth , Witwer Medora , Phipps Erin C , Dumyati Ghinwa , Pierce Rebecca , Cassidy P Maureen , Kainer Marion A , Muleta Daniel , See Isaac
Published: November 2018

Background

Carbapenem-resistant Enterobacteriacae (CRE) are an urgent US public health threat. CDC reported CRE incidence to be 2.93/100,000 population in 2012–2013 in selected sites but changed the CRE surveillance case definition in 2016 to improve sensitivity for detecting carbapenemase-producing (CP) CRE. We describe CRE epidemiology before and after the change.

Methods

Eight CDC Emerging Infections Program sites (CO, GA, MD, MN, NM, NY, OR, TN) conducted active, population-based CRE surveillance in selected counties. A case was defined as having an isolate of E. coli, Enterobacter, or Klebsiella meeting a susceptibility phenotype (figure) at a clinical laboratory from urine or a normally sterile body site in a surveillance area resident in a 30-day period. We collected data from medical records and defined cases as community-associated (CA) if no healthcare risk factors were documented. A convenience sample of isolates were tested for carbapenemase genes at CDC by real-time PCR. We calculated incidence rates (per 100,000 population) by using US Census data. Case epidemiology and the proportion of CP-CRE isolates in 2015 versus 2016 were compared.

Results

In total, 442 incident CRE cases were reported in 2015, and 1,149 cases were reported in 2016. Most isolates were cultured from urine: 87% in 2015 and 92% in 2016 (P < .001). The crude overall pooled mean incidence in 2015 was 2.9 (range by site: 0.45–7.19) and in 2016 was 7.48 (range: 3.13–15.95). The most common CRE genus was Klebsiella (51%) in 2015, and in 2016 was Enterobacter (41%, P < 0.001). Of the subset of CRE isolates tested at CDC, 109/227 (48%) were CP-CRE in 2015 and 109/551 (20%) were CP-CRE in 2016. In 2015, 52/442 (12%) of cases were CA CRE, and in 2016, 267/1,149 (23%) were CA CRE (P < 0.001). In 2016, 3/111 (2.7%) of CA CRE isolates tested were CP-CRE.

Conclusion

A large increase in reported CRE incidence was observed after the change in the case definition. The new case definition includes a substantially larger number of Enterobacter cases. A decrease in CP-CRE prevalence appears to be driven by an increase in non-CP-CRE cases. Although CP-CRE in the community still appear to be rare, a substantial proportion of phenotypic CRE appear to be CA, and CDC is undertaking efforts to further investigate CA CRE, including CP-CRE.

Disclosures

G. Dumyati, Seres: Scientific Advisor, Consulting fee.
1762. The Adjusted Ranking Metric (ARM) and Its Use in Composite Measures for HAI Prevention in the National Healthcare Safety Network (NHSN)
Authors: Sapiano Mathew R P , Edwards Jonathan R , Pollock Daniel
Published: November 2018

Background

The National Healthcare Safety Network (NHSN), developed and used by the Centers for Disease Control and Prevention (CDC) for surveillance of healthcare-associated infections (HAIs), provides benchmark measures, such as standardized infection ratio (SIRs), that CDC and its partners in healthcare and public health use for prevention purposes. NHSN provides benchmarks for each HAI measure separately, but a composite HAI measure could provide a more rounded assessment of HAI problems and prevention opportunities.

Methods

Several issues must be addressed to produce a sound HAI composite measure, the most of which is that the SIR can be inaccurate for facilities with low HAI exposure (e.g., low device days, operative procedure volume). We remedy this issue with the Adjusted Ranking Metric (ARM), a new measure that reliability-adjusts the SIR using a Bayesian mixed effects model. The ARM is particularly useful in the production of a composite measure because ARMs are well-suited to comparison between facilities. The composite was therefore produced by applying adjustments to the ARMs to account for (1) differences between exposure to separate HAI types within facilities and (2) differences in frequency and severity between HAIs. The composite is calculated for 6 HAIs based on 2015 data.

Results

Case studies of 3 facilities (table) show that the new composite measure provides a meaningful measure of overall facility performance that is less prone to the biases that afflict simple combinations of SIRs.

Conclusion

We introduce a framework for calculating a composite HAI measure that is flexible, customizable, and transparent. The current implementation of the framework is intended to assist in prevention efforts and can be easily modified to include cost weights, if desired. Flexibility in weighting the HAIs provides an opportunity for different stakeholders to customize the composite measure to their own needs.

Disclosures

All authors: No reported disclosures.
1773. Impact of Antibiotics Used to Treat Community Acquired Pneumonia on the Gut Microbiome and Resistome in Healthy Volunteers
Authors: Anthony Winston , Wang Bin , Cass Candice , Hink Tiffany , Reske Kimberly , Seiler Sondra , Dubberke Erik R , Burnham Carey-Ann D , Dantas Gautam , Kwon Jennie H
Published: November 2018

Background

Antibiotics (ABX) are frequently inappropriately used to treat nonbacterial causes of respiratory illnesses. The goal of this prospective cohort study was to characterize the impact of ABX used to treat community-acquired pneumonia (CAP) on the fecal microbiome and resistome in healthy volunteers (HV).

Methods

Twenty HVs were randomized to receive 5 days of levofloxacin (LV), azithromycin (AZ), cefpodoxime (CF), or AZ+CF. Stool was collected before, during, and after ABX, then underwent microbiologic culture and shotgun sequencing. DNA was extracted, then sequenced using the Illumina NextSeq platform. Relative abundance of bacterial taxa was estimated by MetaPhlAn and antibiotic resistance gene (ARG) composition by ShortBRED. Analysis was in R.

Results

The mean HV age was 37 (range 24–59) and 10 were female. Species diversity measured via Shannon Index and richness were significantly lower in samples taken from all HVs 3 days post-ABX (P < 0.01 for all). While nonmetric multidimensional scaling (NDMS) ordination shows high interpatient dissimilarity (Bray–Curtis) for most samples, the post-ABX intrapatient dissimilarity varies by ABX. The AZ group exhibited chronic alterations in taxa dissimilarity and the CF group had increases in dissimilarity directly post-ABX. The CF+AZ group displayed both acute and persistent perturbations (Figure 1). Although there was no significant change in ARG richness post-ABX, there was a significant increase in overall ARG abundance across all samples (P < 0.003). Within each ABX, there were unique changes in ARG abundance, and groups with CF had increases in ARG abundance (Figure 2).

Conclusion

ABX used to treat CAP can cause acute microbiome disruptions, as evidenced by decreased microbiome species diversity and richness, and an increase in ARG abundance post-ABX. The duration of this impact is variable. To prevent microbiome disruptions, measures to prevent inappropriate ABX use via ABX stewardship are necessary.

Disclosures

E. R. Dubberke, Rebiotix: Consultant and Investigator, Consulting fee and Research support. Pfizer: Consultant and Grant Investigator, Consulting fee and Research grant. Synthetic biologics: Consultant, Consulting fee. Merck: Consultant and Investigator, Consulting fee and Research support. Valneva: Consultant, Consulting fee. Achaogen: Consultant, Consulting fee. Alere: webinar, Speaker honorarium. Biofire: webinar, Speaker honorarium.
2568. Variability in Pediatric Antibiotic Prescribing for Upper Respiratory Illnesses by Provider Specialty
Authors: Frost Holly M , McLean Huong , Chow Brian
Published: November 2018

Background

Antibiotic prescribing varies among providers, contributing to antibiotic resistance and adverse drug reactions.

Objective. To evaluate variation in antibiotic prescribing between pediatric and nonpediatric providers for common upper respiratory illnesses.

Methods

Patient encounters for children aged <18 years from a regional healthcare system were identified. Electronic medical records from 2011 to 2016 were extracted for diagnoses of upper respiratory infection (URI), pharyngitis, acute otitis media (AOM), and sinusitis. Encounters with competing medical diagnoses, recent hospitalization, and antibiotic prescriptions within 30 days were excluded. Adherence to antibiotic guidelines was assessed by provider training (pediatric, nonpediatric physicians, and advance practice providers [APP]). Additional factors assessed included clinic or urgent care setting, calendar year, and patient’s age, gender, insurance status, and number of sick visits in the prior year.

Results

Across 6 years, 141,361 visits were examined: 43,914 for URI, 43,701 for pharyngitis, 43,925 for AOM, and 9,821 for sinusitis. Pediatricians were more likely than APPs and nonpediatric providers to have guideline-concordant prescribing for pharyngitis (pediatricians 66.7 (54.5, 77.0)%, nonpediatricians 49.1 (36.3, 62.0)%, APPs 52.2(39.4, 64.7)%, P < 0.0001) and sinusitis (pediatricians 70.8(53.8, 83.4)%, nonpediatricians 63.3(46.8, 77.2)%, APPs 62.1(45.1, 76.5)%, P = 0.48) and to withhold antibiotics for URI than APPs and nonpediatric providers (pediatricians 86.6(81.2, 90.6)%, nonpediatricians 80.8(73.0, 86.8)%, APPs 76.8(68.4, 83.5)%, P < 0.0001). Pediatricians were less likely to prescribe antibiotics for pharyngitis without a positive Group A Streptococcus test than APPs and nonpediatric providers (pediatricians 15.1(10.4, 21.6)%, nonpediatricians 29.4(20.8, 39.6)%, APPs 27.2(19.3, 36.9)%, P < 0.0001). First-line antibiotic prescribing for pharyngitis and AOM did not differ between provider specialties. A trend toward more guideline-concordant prescribing was seen for pharyngitis and sinusitis over the study period.

Conclusion

Pediatricians were more likely to adhere to guidelines for pediatric acute respiratory infections. Pediatric antibiotic stewardship efforts should also target non-pediatricians.

Disclosures

All authors: No reported disclosures.
1192. Identification of a Novel Enterobacter cloacae Isolate Producing an IMP-13 Metallo-β-Lactamase
Authors: Abid Muhammad Bilal , Buchan Blake , Ledeboer Nathan , Munoz-Price L Silvia , Graham Mary Beth
Published: November 2018

Background

Metallo-β-lactamases (MBLs) have been identified as emerging resistance determinants in Enterobacteriaceae, A. baumanii, and P. aeruginosa. Early identification of carbapenemase-producing organisms (CPOs) is essential to prevent dissemination within healthcare settings. We report a case of a patient who was blood culture positive for a multidrug-resistant E. cloacae which was subsequently found to be positive for the MBL blaIMP-13.

Methods

A 74-year-old female, with no significant past medical or travel history, developed sepsis 2 days after undergoing debulking surgery for stage IIIc ovarian carcinoma. Blood cultures were positive for Gram-negative bacilli and the organisms identified as Enterobacter spp. with blaIMP MBL (Verigene). Antimicrobial susceptibility testing demonstrated high-level resistance to all penicillins, ureidopenicillins, cephalosporins, and β-lactam/inhibitor antibiotics, and susceptibility to colistin, tigecycline, and monobactams.

Results

Further testing using micro-broth dilution, BD phoenix, and Etest, demonstrated susceptible MICs to meropenem and imipenem, with intermediate to resistant MICs to ertapenem. The patient was treated with a combination therapy of amikacin, aztreonam, and ceftazidime-avibactam and responded clinically. Per standard protocol, the organism was sent to WI Laboratory of Hygiene for further characterization. Phenotypic testing using the modified carbapenem inactivation test (mCIM) was positive, indicating the presence of a carbapenemase; however, results using Xpert CarbaR (Cepheid) were negative. Subsequent sequencing of the isolate confirmed the presence of blaIMP-13.

Conclusion

This was an important case for several reasons. First, blaIMP-13 is historically reported in Pseudomonas aeruginosa. Indeed, this was the first report of Enterobacteriaceae harboring blaIMP in WI. Second, it had unique susceptibility pattern to carbapenems and was not detected by the CarbaR. Third, these data demonstrate clinical success in treating an MBL CPO with a combination anti-microbial regimen, based on an understanding of resistance mechanisms involved. This report calls for more vigilant screening for CPO using both phenotypic and genotypic methods.

Disclosures

N. Ledeboer, Luminex: Consultant, Consulting fee.
1194. Carbapenem-Resistant Enterobacteriaceae in Kentucky: Initial 6 Months of Mechanism Testing
Authors: Spicer Kevin , Cox Katelyn , Zinner Rachel , Flinchum Andrea
Published: November 2018

Background

A global rise in carbapenem-resistant Enterobacteriaceae (CRE) has been noted over the past two decades. State and local data on CRE are necessary to better inform public health interventions.

Methods

Reporting of CRE (i.e., Enterobacteriaceae resistant to any carbapenem or shown to produce a carbapenemase) was mandated in Kentucky in 2015. Voluntary submission of isolates to the Antibiotic Resistance Laboratory Network regional laboratory for carbapenemase testing began September 2017. Demographic data collected as part of reporting included age, sex, county of residence, and inpatient/outpatient status. Descriptive and chi-square analyses were performed.

Results

Between September 1, 2017 and February 28, 2018, 149 CRE were reported to the Kentucky Department for Public Health. Testing for presence of a carbapenemase was performed on 115 isolates (77.2%); 44 (38.3%) were carbapenemase producing (CP)-CRE and Klebsiella pneumoniae carbapenemase (KPC) was identified from 38 (86.4%). Also identified were Verona integron-encoded metallo-β-lactamase (VIM; 5, 11.4%) and New Delhi metallo-β-lactamase (NDM; 1, 2.3%). Identification of carbapenemase varied among genera: Citrobacter (3/4, 75%), Klebsiella (21/40, 52.5%), Serratia (2/5, 40%), Escherichia (6/20, 30%), Enterobacter (11/41, 26.8%), Proteus (0/4, 0%), other genera (1/2, 50%). CRE isolates from urban or suburban areas were more likely CP-CRE than were those from rural areas (30/65, 46.2% vs. 14/50, 28%, P = 0.047). Carbapenemase was identified more often among CRE isolates from currently hospitalized patients than from patients whose cultures were collected outside of an acute care hospital (37/70, 52.8% vs. 7/45, 15.6%; P < 0.001).

Conclusion

The percentage of CRE that were CP-CRE in Kentucky was comparable with that reported for the United States (38 vs. 32%). Klebsiella spp., the genera historically associated with CP-CRE, made up less than half of CP-CRE. CP isolates were identified from urban, suburban, and rural settings and more frequently from isolates collected in hospitals compared with the community. The additional epidemiology obtained as part of this reporting system has identified metropolitan areas of the state as targets for CRE prevention efforts.

Disclosures

All authors: No reported disclosures.
1203. Molecular Screening for Multi-Drug Resistance Genes in Hospitalized Veterans
Authors: Alsamarai Sarah , Biedron Caitlin , Holen Barrett , Goodman Jesse , Yoon Bona , Liappis Angelike P
Published: November 2018

Background

Gene-based screening is a tool to detect and track multi-drug-resistant organisms (MDROs) in hospitalized patients. MDRO acquisition and colonization during the duration of a hospital stay and their persistence over time are not well described.

Methods

A peri-anal swab was collected within 48 hours of admission from patients on medical wards and the MICU at the Washington DC VA Medical Center and repeat swabs were obtained day 7 and 14 on patients consenting to participate. Clinical and laboratory data from admission to 12mo post discharge was reviewed. Genes associated with VRE (VanA), ESBL (CTX-M), carbapenase-producing organisms or CPOs (OXA-23, OXA-51) and CREs (KPC,NDM,VIM, IMP, OXA-48) were tested on swabs by the Acuitas-MDRO Test (OpGen, Inc.).

Results

Between July 2015 and August 2016, 565 hospitalized patients were screened with 210 swabs collected from 182 subjects. One swab was nonevaluable. Subjects had a mean age 67.5 ± 12.0 years (26–94 years, 38% ≥70 years) and 39% received empiric antibiotics at admission. Subjects were hospitalized for 1037 cumulative bed-days (1–81 days) with median LOS of 3 days; 84% (152/182) had a stay of a week or less. Among those who remained hospitalized long enough for serial testing, 45% were willing or able to provide >1 swab. Those with >1 swab were significantly older (+4.9 years, P = 0.03), more likely to have to have been admitted for an infectious diagnosis (48% vs. 24%, P = 0.02). All subjects negative for MDRO genes on admission with >1 swab remained negative on serial sampling. Sixteen subjects (8.8%) had one or more genes present on screening and all three with >1 swab had persistence of that gene on repeat sampling. Genes harbored included CTX-M (4.4%), VanA (4.4%), OXA-51(0.6%), KPC (0.6%).

Conclusion

The rate of occult MDRO colonization was low in our predominately elderly hospitalized patients. The majority of consenting participants were discharged before swabs could be repeated. Serial sampling revealed that results of swabs persisted over time in the same subject despite treatments received during hospitalization, including exposures to antibiotics. The identification of occult MDRO carriage during a hospitalization, even when obtained after admission, may have utility in guiding treatment for providers.

Disclosures

All authors: No reported disclosures.
1216. Cost-Effectiveness of Penicillin Skin Allergy Testing in Methicillin-Sensitive Staphylococcus aureus (MSSA) Bacteremia
Authors: Meninger Stephen , Heil Emily , Mattingly II T Joseph
Published: November 2018

Background

β-Lactams remain the gold standard for treatment of MSSA bacteremia due to superior outcomes compared with vancomycin. Approximately nine in 10 patients receiving penicillin skin testing (PST) will be de-labeled of a penicillin allergy and able to receive a β-lactam antibiotic. The study aims to evaluate the cost-effectiveness of penicillin allergy confirmation during acute care admission for methicillin-sensitive staphylococcus aureus (MSSA) bacteremia through a PST service.

Methods

A decision tree analysis was used to compare a PST intervention in patients with a registeredpenicillin allergy during an inpatient admission for MSSA bacteremia vs. usual care (No PST). The model was created from the health sector perspective with a 1-year time horizon. Patients with a penicillin allergy label were expected to receive vancomycin while patients with no penicillin allergy were expected to receive cefazolin. Potential inpatient, outpatient, and adverse reaction costs were considered in all arms of the model. The effects were measured in quality adjusted life years (QALY) and were calculated for patients who were cured, hospitalized, experienced severe adverse events, or died from MSSA infection.

Results

Patients who received PST services had a mean yearly cost of $12,802, mean quality adjusted life years (QALY) of 0.70, and mean cost/QALY of $18,311. The comparator group not receiving PST services had a mean yearly cost of $12,264, mean quality adjusted life years (QALY) of 0.64, and mean cost/QALY of $19,192. The model produced a final base case ICERof $8,966/QALY for receiving a PST during a hospital admission for the treatment of methicillin-sensitive staphylococcus aureus (MSSA) bacteremia.

Conclusion

Penicillin allergy confirmation through PST services was cost-effective for patients with a reported penicillin allergy admitted for MSSA bacteremia. Additional research to determine potential benefits of PST services beyond one year could further improve the cost-effectiveness of this intervention.

Disclosures

S. Meninger, ALK-Abelló: Grant Investigator, Research grant. E. Heil, ALK-Abelló: Grant Investigator, Research grant. T. J. Mattingly II, ALK-Abelló: Grant Investigator, Research grant.
1220. Impact of Mandatory Infectious Diseases Consultation on the Use of Core Measures and Mortality in Staphylococcus aureus Bacteremia (SAB) at an Academic Medical Center
Authors: Gancher Elizabeth , Maslak Gregory , Lustgarten Jonathan , Schultz Sara , Ingilizova Marinela
Published: November 2018

Background

Multiple studies have shown that Infectious Diseases (ID) consultation significantly improves adherence to guidelines for patients with SAB and decreases mortality. Data from a prior retrospective study done at Hahnemann University Hospital showed that ID consultation improved the use of guideline-based core measures for SAB management. Based on these data, a mandatory ID consultation was established at our institution in November 2016.

Methods

A retrospective, observational study was conducted to evaluate patient characteristics, adherence to core measures for SAB, and in-hospital mortality. All patients with at least one documented blood culture positive for S. aureus were stratified into two groups: pre-mandatory consult (January 1, 2014–November 1, 2016) and post mandatory consult (November 2, 2016–February 1, 2018).

Results

Three hundred seventy-three discrete episodes of SAB were included in the final analysis, 238 episodes before mandatory consult, and 135 episodes after the mandatory consult policy was enacted. Mandatory consultation significantly improved the use of the following core measures for SAB: surveillance blood cultures (87.7% pre vs. 99.2% post, P < 0.001), echocardiography (81.9% vs. 96.9%, P < 0.001), early targeted antimicrobial therapy with nafcillin or cefazolin in MSSA (71.7% vs. 88.6%, P < 0.001), and appropriateness of final antibiotic choice (80.2% vs. 95.2%, P < 0.001). In addition, in-hospital mortality (15.4% vs. 6.2%, P = 0.011), and infection-related mortality (14.3% vs. 5.6%, P = 0.011) were found to be statistically significantly lower in the post mandatory consultation patients.

Conclusion

Implementation of a mandatory ID consultation for patients with SAB at our institution was associated with increased adherence to guideline-based core measures for management of SAB, and decreased in-hospital and infection-related mortality. Our results suggest that mandatory ID consultation for SAB should be considered at all institutions.

Disclosures

All authors: No reported disclosures.
1222. Risk Factors and Outcomes for Daptomycin Nonsusceptible Methicillin-Resistant Staphylococcus aureus Bloodstream Infections
Authors: Hadid Hind , Rizvi Hira , Misikir Helina , Baratz Nathalie , Bardossy Ana Cecilia , Sundaram Ayesha , Haddad Lillian , Perri Mary Beth , Zervos Marcus , Herc Erica
Published: November 2018

Background

Daptomycin (dap) has been approved and successfully used for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. However, reports of daptomycin nonsusceptible (DNS) MRSA strains have emerged over the recent years. This study describes the clinical characteristics of patients with DNS MRSA bloodstream infections (BSIs) with the objective of identifying risk factors and outcomes.

Methods

This is a retrospective case–control study in a tertiary healthcare system in southeast Michigan. Cases included 34 patients with DNS MRSA BSI between September 24, 2005 and March 31, 2018. Cases were matched with controls with MRSA BSI based on age, source of BSI, and time-period of BSI in a 1:1 ratio. Charts were reviewed for clinical and laboratory data. Vancomycin (van) and dap minimum inhibitory concentrations (MICs) were determined by E-test. DNS was defined as an MIC >1.0 µg/mL. Chi-square test, Fisher’s exact test, and t-test were used to determine statistical significance.

Results

In the case cohort, the source of BSI was endovascular in 11(32%) patients, central-line associated in 3(9%), secondary BSI in 13(38%), and unknown in 7(21%). Table 1 is a summary of the results.

Conclusion

Prior exposure to dap and van, and higher van MIC in MRSA isolates are risk factors for DNS MRSA BSI. DNS is associated with significantly higher risk of 90-day MRSA BSI recurrence.

Disclosures

All authors: No reported disclosures.
1232. Phylogenomics of Enterococcus faecium From South America: Revisiting Worldwide VRE Population Structure
Authors: Rios Rafael , Reyes Jinnethe , Carvajal Lina P , Kolokotronis Sergios-Orestis , Planet Paul , Narechania Apurva , Munita Jose , Arias Cesar , Diaz Lorena
Published: November 2018

Background

Previous studies have suggested that the population structure of E. faecium is composed of two main clades; a commensal clade (designated clade B) and a hospital-associated clade (Clade A) that encompass most of the clinical and animal isolates. The phylogenetic analyses leading to these results have been accomplished with the notable absence of isolates from diverse geographical regions (including South America). We aimed to refine the worldwide population structure of E. faecium by including 55 representative genomes from isolates obtained from five Latin American countries recovered between 1998 and 2014.

Methods

We sequenced our 55 representative isolates and selected other 285 genomes, from public databases, obtained across different regions (36 countries), different sources (animal, commensal, and clinical strains) and a wide range of dates of isolation (1946–2017). We characterized the genomes by presence/absence of resistance, virulence and mobile elements, and of CRISPR-cas systems. We analyzed the phylogeny of the entire population, selected the genomes belonging to clade A to examine recombination patterns and performed Bayesian molecular clock analysis excluding recombinant regions.

Results

Two major clades were identified, as previously reported. However, a higher degree of variation in clade A was found. Indeed, we identified a subclade (subclade I) that diverged ~894 years ago, and clearly distinguished clinical isolates from those of animal origin (distributed among a number of smaller early-branching subclades). A further split within the clinical subclade (subclade II) that diverged around ~371 years ago was also evident. Latin American isolates were distributed within subclades I (48%) and II (42%). Isolates in “animal” branches exhibited an average recombination of 34 Kbp, where it was 5 Kbp and 21 Kbp for subclades I and II, respectively. More resistance determinants were found in subclade II (62%), followed by I (54%) and absence of cas was the norm in the clinical subclades.

Conclusion

Inclusion of E. faecium isolates from diverse geographical region supports a continuous evolution of these organisms causing human infections. Important evolutionary events seem to favor emergence of novel subclades capable to cause important morbidity and mortality.

Disclosures

J. Munita, Pfizer: Grant Investigator, Research grant. C. Arias, Merck & Co., Inc.: Grant Investigator, Research support. MeMed: Grant Investigator, Research support. Allergan: Grant Investigator, Research support.
1250. Prevalence and Risk Factors for Acquiring Carbapenem-Resistant Enterobacteriaceae in an Intensive Care Unit at a Tertiary Hospital
Authors: Kang Jin Suk , Lee Soon Ok , Lee Jeong Eun , Kim So Ra , Kim Han Wool , Hong Seung Hyun , Kim Hye Won , Jang Mi Jin , Shin Sun Hea , Ha Hyun Jung , Park Nam Jeong , Ko Mee Kyung , Yi Jongyoun , Kim Kye-Hyung
Published: November 2018

Background

Active surveillance testing of carbapenem-resistant Enterobacteriaceae (AST-CRE) is recommended in high-risk settings, such as intensive care units (ICUs), to prevent CRE outbreaks or invasive infections. This study aimed to investigate the effects of AST-CRE by analyzing the prevalence and risk factors for acquiring CRE during the ICU care.

Methods

We conducted AST-CRE on rectal swabs of patients admitted to the ICU in the emergency room at a tertiary hospital in South Korea for 12.5 months. AST-CRE was performed upon admission and weekly thereafter. To assess the risk factors of acquiring AST-CRE during the admission period in adult patients, those colonized with CRE upon admission and aged <18 years were excluded. AST-CRE was performed using Centers for Disease Control and Prevention methods. A polymerase chain reaction assay was performed to detect five carbapenemase genes (NDM, KPC, VIM, IMP, and OXA).

Results

A total of 810 patients were admitted during the study period. The acquisition rate and carbapenemase-producing CRE were 2.6% (21/810) and 42.9% (9/21), respectively. No invasive infection due to CRE was found. The most common species were Klebsiella pneumoniae (71.4%, 15/21), and eight KPC and one NDM genes were detected. In CRE-positive patients, in-hospital mortality and length of hospitalization were higher (P = 0.003) and longer (P < 0.001), respectively. Multivariate analyses showed that male gender (adjusted odds ratio [aOR] 8.0; 95% confidence interval [CI] 1.7–36.8), previous hospitalization in the last year (aOR 5.1; 95% CI 1.6–16.4), co-colonization with multidrug-resistant Acinetobacter species (aOR 18.3; 95% CI, 4.2–79.2) and extended-spectrum β-lactamase-producing bacteria (aOR 3.4; 95% CI, 1.1–10.9), and length of ICU admission until CRE detection for ≥10 days (aOR 6.5; 95% CI 2.2–19.2) were independently associated with CRE acquisition.

Conclusion

To prevent CRE outbreak or invasive infections, patients admitted in the ICU should be screened using AST-CRE.

Disclosures

All authors: No reported disclosures.
1252. A Challenging Burkholderia Outbreak Investigation Across Multiple Units at an Academic Medical Center From June 2017 to February 2018
Authors: Greendyke William , Hill-Ricciuti Alexandra , Oberhardt Matthew , Green Daniel , Wu Fann , Whittier Susan , Saiman Lisa , Furuya E Yoko
Published: November 2018

Background

Most outbreak investigations involve short-term, geographically localized clusters. However, some organisms can form environmental reservoirs leading to more prolonged, widespread outbreaks. We describe a prolonged outbreak of Burkholderia at our institution.

Methods

An epidemiological investigation was conducted. Burkholderia isolates were genotyped using pulsed-field gel electrophoresis (PFGE) and recA gene sequencing. Initial isolates were sent to a national reference laboratory for multilocus sequence typing (MLST).

Results

32 patients on 12 units (see figure) had ≥1 positive culture for Burkholderia from June 2017 to February 2018. 21 had B. cenocepacia (PFGE pattern A, recA allele 365) and 11 had B. cepacia (PFGE pattern C, recA allele 53). MLST revealed that isolates with recA allele 365 were unique compared with previously identified B. cenocepacia strains. Of 32 patients, 28 (88%) had positive respiratory cultures. Of 32 patients, 3 (9%) had bacteremia. Thirty-day mortality was 4/29 (14%). A case–control study did not reveal a common point source. All surveillance cultures from asymptomatic patients were negative (n = 53). Two of nine sink drains in rooms of cases were positive for an unrelated strain of B. cepacia. Other environmental cultures were negative for Burkholderia (n = 49). Cases continued despite routine interventions (see figure), with some incident cases detected long after potential exposures. Ventilator/respiratory equipment (V/RE) cleaning was investigated. Multiple V/RE interventions were implemented: (1) ensuring a sterilization process for ventilator temperature probes (used in heated humidification) was occurring; (2) using disposable manometers on contact isolation patients; (3) reinforcing ventilator cleaning, including those in radiology suites after use.

Conclusion

No definitive source of the outbreak was found. New cases continued after reinforcement of basic infection control practices, but subsided after focused attention on V/RE cleaning practices. Control of this outbreak was challenging due to the complexity of a prolonged “latency period” for Burkholderia, difficulty identifying reservoirs, and multiple possible modes of transmission, especially for organisms like Burkholderia that can persist on environmental surfaces and equipment.

Disclosures

All authors: No reported disclosures.
1257. Assessing Risk Factors for an Outbreak of Burkholderia cenocepacia in Non-cystic Fibrosis (CF) Patients
Authors: Hill-Ricciuti Alexandra , Greendyke William , Oberhardt Matthew , Wu Fann , Green Daniel , Whittier Susan , Larson Elaine , Saiman Lisa , Furuya E Yoko
Published: November 2018

Background

Burkholderia spp. have been associated with outbreaks of healthcare-associated infections in non-CF patients, mostly attributable to point sources of contaminated solutions or medications. Fewer non-point source outbreaks have been described.

Methods

We conducted a matched case:control (1:3) study to assess risk factors for B. cenocepacia during an outbreak that occurred in 2017 in a 738-bed university-affiliated hospital involving patients hospitalized on several ICUs and non-ICUs. Clinical isolates identified as B. cepacia complex were speciated using sequencing of the recA allele and genotyped by pulsed field gel electrophoresis (PFGE). Case subjects were patients with a positive culture for the B. cenocepacia outbreak strain (PFGE pattern 17-A, recA 365) from June 1–December 31, 2017. Control subjects had negative respiratory cultures for Burkholderia spp. within 10 days of respective cases’ culture dates and were hospitalized on the same unit at the same time as respective cases. Potential risk factors including procedures, devices, and medications (previously linked to point source outbreaks) were examined. A 5-day exposure window was studied for procedures and devices as this was the shortest interval noted between a case subject’s negative and first positive culture. Exact conditional logistic regression was used to analyze risk factors; Mann–Whitney U and Fisher’s exact tests were used to compare demographic and clinic characteristics of case and control subjects.

Results

Seventeen cases (all with positive respiratory tract cultures) and 41 unit-matched controls were studied. Case and control subjects had similar demographic characteristics, illness severity, and comorbidities. No point source was identified. Only exposure to invasive mechanical ventilation was associated with case status (OR: 10.5, [CI95 1.9, ∞), P = 0.0083). Cases had longer hospital lengths of stay (52 vs. 33 days, P = 0.02) than controls, but similar in-hospital mortality (24% vs.12%, P = 0.43).

Conclusion

These findings suggest that suboptimal infection prevention and control practices related to respiratory interventions, including cleaning and disinfection of ventilators, may have contributed to the outbreak. Reinforcement of best practices helped reduce transmission of the outbreak clone.

Disclosures

All authors: No reported disclosures.
1259. The Local Hospital Milieu and Healthcare-Associated VRE Acquisition
Authors: Zhou Margaret , Li Jianhua , Salmasian Hojjat , Zachariah Philip , Yang Yu-Xiao , Freedberg Daniel
Published: November 2018

Background

The relationship between the local hospital environment and VRE acquisition is not fully understood. The objective of this study was to identify risk factors for healthcare-associated VRE acquisition related to the local hospital milieu.

Methods

This retrospective cohort study included patients admitted to six ICUs at an academic medical center from January 1, 2012 to December 31, 2016 with negative rectal VRE cultures on admission. VRE acquisition was defined as a positive subsequent surveillance swab performed at any time after the initial negative surveillance swab during the index hospitalization. VRE colonization pressure was defined to encapsulate the circulating VRE burden during the at-risk patient’s ICU stay (patient-days of VRE exposure based on concurrently colonized patients on the unit, divided by time at risk). VRE importation pressure was defined to encapsulate the VRE burden at the time of ICU admission (patient-days of VRE exposure on the unit during the preceding 30 days, divided by total patient-days). Multivariable Cox proportional hazards modeling was used, with patients followed until VRE acquisition, death, or for up to 30 days.

Results

There were 161 patients who acquired VRE among 8,485 patients with negative VRE cultures upon admission, including 1,131 patients who had repeat VRE cultures during the index hospitalization. On univariate analysis, patients with VRE acquisition were more likely to have received vancomycin, have had a neighboring patient who received vancomycin, have high VRE importation pressure, or have high VRE colonization pressure. On multivariable analysis, among these factors only high VRE colonization pressure was an independent predictor of VRE acquisition (aHR 1.79, 95% CI 1.19–2.70).

Conclusion

VRE colonization pressure was the most important risk factor for healthcare-associated VRE acquisition in this ICU population, regardless of VRE importation pressure or local use of vancomycin. Interventions seeking to reduce healthcare-associated VRE acquisition may wish to focus on ways to minimize transmission of VRE between patients with known VRE and the local hospital environment.

Disclosures

All authors: No reported disclosures.
1273. Routine Opt-out HIV Screening and Detection of HIV Infection Among Emergency Department Patients
Authors: Fadul Nada , Dortche Ciarra , Baltaro Richard , Reeder Tim
Published: November 2018

Background

The Southeastern United States bears a disproportionate burden of HIV infection, accounting for nearly half of all new cases. The Centers for Disease Control and Prevention released routine opt-out testing recommendations in 2006. Our emergency department collaborated with our infectious diseases clinic (ECU-ID) to implement suggested guidelines among adults since March 2017.

Methods

Our primary aim was to implement routine, opt-out HIV testing in the Vidant Medical Center Emergency Department (ED) for patients between 18 and 65 years of age who have blood work completed, and have not had a test documented in the electronic medical record (EMR) in the last year. A secondary aim was to successfully link HIV-positive patients to care at ECU-ID or preferred clinic. Methods defining programmatic success included developing nurse directed opt-out ordering protocol, integrating testing into normal ED workflow, utilizing the existing EMR to prompt testing, and hiring a linkage coordinator to initiate post-test counseling and linkage-to-care.

Results

Since March 2, 2017, a total of 7,109 HIV tests were performed; an average of 592 monthly tests conducted compared with a previous average of 10 stat tests. Testing increased 5,820% compared with 2015. Of the 21 HIV-positive patients found, 16 were newly diagnosed. Among those newly diagnosed, 14 (87.5%) were linked to care; and among the five known positives, two (40%) were linked to care. Reasons why patients could not be linked included incarceration, refusal to link to care, and re-location.

Conclusion

Joined with the implementation of a routinized ED HIV testing program, a seamless process was developed to link persons found to be positive in the ED to HIV care services; therefore, establishing a systems-level prevention model. Future plans include expanding testing to adolescents and utilizing similar methods to integrate Hepatitis C testing.

Disclosures

All Authors. Gilead Sciences, Inc.: Grant Investigator, Grant recipient and Salary.
1278. Comparing Rates of Routine HIV and HCV Screening to Estimate the Impact of Consent on Identifying Patients With Undiagnosed HIV
Authors: Tlamsa Aileen , Heo Moonseong , Thompson Devin , Moir Lorlette , Shukla Shuchin , Weiss Jeffrey , Litwin Alain , Felsen Uriel
Published: November 2018

Background

HIV and HCV are both treatable viruses for which routine screening among specific age cohorts is recommended. New York State requires patient consent prior to screening for HIV but not HCV. To estimate the impact of the consent requirement, we compared rates of HIV and HCV screening.

Methods

We performed a retrospective study of all adult patients admitted to a tertiary-care hospital in the Bronx, NY, between April 2015 and June 2016. During the study period, automated prompts in the electronic medical record facilitated screening for HIV among patients ages 21–64, and for HCV among patients born between1945-1965. We compared the proportions of patients qualifying for screening for HIV, HCV, or both who were appropriately screened prior to discharge to calculate an adjusted risk difference between performance of HIV and HCV screening. Using the local prevalence of undiagnosed HIV, we estimated the number of missed HIV diagnoses attributable to the difference in screening rates.

Results

A total of 21,413 unique hospitalized patients ages 21–64 and/or born between 1945–1965 were analyzed. Among those qualifying for screening for HIV alone or HCV alone, 39.7% and 58.6% were screened prior to discharge, respectively. Among those qualifying for both HIV and HCV screening, 6.7% were screened for HIV alone, 29.3% were screened for HCV alone, and 30.3% were screened for both. The risk difference between HCV and HIV screening adjusted for patient and admission characteristics was 22.0% (95% CI 20.6%-23.4%). Using an estimated prevalence of undiagnosed HIV of 0.2%, this risk difference corresponds to approximately four (95% CI 3.6–4.1) missed cases of HIV during the study period.

Conclusion

There was a large difference in the number of patients appropriately screened for HIV compared with HCV. While the requirement for consent was the only operational difference in performing routine screening for HIV compared with HCV, differences in how the two viruses are perceived may also have contributed to the observed difference in screening rates. Nevertheless, our findings suggest that removing the requirement for consent prior to HIV screening may increase the number of cases of previously undiagnosed HIV identified by routine screening.

Disclosures

All authors: No reported disclosures.
1282. Detection of HIV Transmitted Drug Resistance by Next-Generation Sequencing in a CRF01_AE Predominant Epidemic
Authors: Salvana Edsel Maurice , Dungca Nina , Arevalo Geraldine , Leyritana Katerina , Francisco Christian , Penalosa Christine , Destura Raul , Lim Jodor , Schwem Brian
Published: November 2018

Background

The Philippines has the fastest growing HIV epidemic in the Asia-Pacific. Concurrent with this is a subtype shift from B to CRF01_AE. We have previously documented transmitted drug resistance (TDR) locally. However, the lack of drug pressure and the insensitivity of Sanger-based sequencing (SBS) may leave archived drug-resistance mutations (DRMs) undetected. To better detect TDR, we performed next-generation sequencing (NGS) on treatment-naïve patients and compared this with SBS.

Methods

Following ethics approval, newly-diagnosed adult Filipino HIV patients were recruited from the Philippine General Hospital HIV treatment hub. Demographic data were collected, and blood samples underwent SBS with a WHO-approved protocol. Whole-genome NGS was performed using Illumina HiSeq through a commercial provider (Macrogen, Korea). Genotype and DRMs were analyzed and scored using the Stanford HIV Drug Resistance Database.

Results

113 patients were analyzed. Median age was 29 years (range 19–68), mean CD4 count was 147 cells/µL (range 0–556) and median viral load was 2.8 × 106 copies/mL. Genotype distribution was: CRF01_AE (93), B (13), possible CRF01_AE/B recombinants (5), CRF02_AG (1), possible URF (1). TDR prevalence by SBS and NGS at different minority variant cutoffs are shown in Table 1. All DRMs on SBS were found on NGS. Some samples had multiple DRMs. No factors were significantly associated with TDR, genotype, viral load or baseline CD4 count.

Conclusion

NGS is a more sensitive tool for detecting TDR compared with SBS. Nearly double the DRMs were found at an NGS cutoff of ≥5%, including INSTI DRMs. With increasing HIV drug resistance worldwide, switching to NGS may help decrease rates of initial treatment failure, especially in settings with limited repertoires of ARVs.

Disclosures

All authors: No reported disclosures.
1287. Seizing Opportunities for Intervention: Changing HIV Knowledge Among Men Who Have Sex With Men and Transgender Women Attending Trusted Community Centers in Nigeria
Authors: Jones Milissa , Omari Habib , Adebajo Sylvia , Gaydos Charlotte , Kokogho Afoke , Baral Stefan , Nowak Rebecca , Ake Julie , Charurat Manhattan , Robb Merlin L , Crowell Trevor A ,   TRUST/RV368
Published: November 2018

Background

Knowledge of HIV risk factors and risk reduction strategies is essential for HIV prevention in key populations, including men who have sex with men (MSM) and transgender women (TGW). We described factors associated with HIV-related knowledge and evaluated the impact of counseling and care at trusted community health centers serving Nigerian MSM and TGW.

Methods

The TRUST/RV368 cohort recruits MSM and TGW via respondent driven sampling in Abuja and Lagos, Nigeria. Participants undergo a structured interview with five knowledge-testing questions at enrollment and after 9 and 15 months. Routine HIV/STI screening, free condoms/lubricants, and counseling about safer sex practice is provided. Multivariable Poisson regression with generalized estimating equations was used to calculate risk ratios (RRs) and 95% confidence intervals (CIs) for factors associated with answering more knowledge questions correctly. Pearson’s chi-squared test was used to compare the proportion of participants answering each question correctly at enrollment and subsequent visits.

Results

From March 2013 to December 2017, 2,090 biological males were enrolled with median age 23 [interquartile range 20–27] years, including 234 (11.2%) with female gender identity. Of 1691 participants with known HIV status, 836 (49.4%) were positive. The mean number of HIV knowledge questions correctly answered was 2.37, 2.98, and 3.09 at enrollment, 9, and 15 months, respectively. Participants demonstrated increased HIV knowledge after 9 (RR 1.15 [95% CI 1.03–1.28]) and 15 months (1.18 [1.05–1.32]). Factors associated with increased knowledge included HIV positivity (1.17 [1.11–1.23]), higher than senior secondary education when compared with less than senior secondary (1.24 [1.12–1.37]), and almost daily internet use when compared with never (1.17 [1.08–1.27]). Knowledge gains were driven primarily by improved understanding of condom and lubricant use (figure).

Conclusion

While HIV knowledge improved during enrollment in the cohort, it remained suboptimal. Multiple modalities may be needed to fully inform Nigerian MSM and TGW of risk reduction strategies. Interventions that involve internet access to deliver educational materials may be a useful adjunct to direct counseling at healthcare centers.

Disclosures

All authors: No reported disclosures.