bluuebunny/crossref_metadata_2025_split huggingface dataset:
577. The Role of Healthcare Worker-Mediated Contact Networks in the Transmission of Vancomycin-Resistant Enterococci
Authors: Klein Eili , Hinson Jeremiah , Tseng Katie K , Smith Aria , Toerper Matthew , Amoah Joe , Levin Scott , Milstone Aaron 
Published: October 2019

Abstract

Background
Healthcare workers (HCWs) commonly contact multiple patients daily and serve as an important vector for transmission of pathogens such as vancomycin-resistant enterococci (VRE). Characterizing the HCW-patient network is difficult, which limits understanding of the role of HCWs in the horizontal transmission of pathogens. Electronic health records (EHR) present an opportunity to generate HCW-mediated contact networks and evaluate their impact on transmission.

Methods
Retrospective analysis of patients (PT) admitted to a medical intensive care unit and solid-organ transplant unit between July 2016 and June 2017. Clinical and demographic information, including VRE surveillance swab outcomes, were extracted from the hospital EHR system. PT-HCW-PT connections were defined as HCW contacts with a patient within an hour of another patient. Multi-variable logistic regression was used to analyze factors associated with unit-acquired VRE colonization incidence.

Results
A total of 2,336 patients had a recorded interaction with 4,956 unique HCWs. 146 patients were colonized with VRE on unit-admission, and 29 patients had unit-acquired VRE colonization. HCWs had contact with ~2 (range: 1–23) patients a day and ~6 (range: 1–58) contacts with patients per day (Figure 1), though rates varied by HCW-type. Patients were contacted by ~7 different HCWs resulting in ~28 contacts per day, with nurses being the most common (Figure 2). This resulted in approximately 10 PT-HCW-PT connections per day (range: 1–33) to an average of 3 other patients. After adjusting for known VRE acquisition risk factors, HCW connections to other patients with VRE significantly increased the risk of VRE acquisition (odds ratio = 1.32; 95% CI: 1.20–1.44; Table 1).

Conclusion
Understanding how HCWs connect patients can elucidate how pathogens, such as VRE, spread in the hospital. We demonstrated how EHR data can inform how HCWs connect patients to spread HAIs and the impact of those connections on the spread of VRE. Though EHR data have limitations, as certain activities and contacts are not logged into the system, they provide a scalable and generalizable source for understanding how patients are connected and can be utilized to reduce the spread of nosocomial infections.

Disclosures
All authors: No reported disclosures.
580. Association Between Central Venous Catheter Repair and Bloodstream Infections in a Pediatric Oncology Center
Authors: Barbar Ruba , Hakim Hana , Flynn Patricia , Gaur Aditya H , Wright Darenda , Owings Angie , Su Yin , Tang Li 
Published: October 2019

Abstract

Background
Central venous catheters (CVCs) are important for healthcare delivery in pediatric oncology patients. It is common to repair CVC breakage to prevent replacement. Existing evidence regarding the association between CVC repair and bloodstream infections (BSI) is limited in the general pediatric population and lacking in pediatric oncology patients. We aim at evaluating whether repairing broken CVCs is associated with an increased risk for subsequent BSI in a pediatric oncology center.

Methods
This is a retrospective case-crossover study of pediatric oncology patients with broken CVCs that underwent repair between July 2015 and June 2017. The incidence and characteristics of BSI in the 30-day pre-repair period were compared with those in the 30-day post-repair period. Wilcoxon-Mann–Whitney and Fisher’s Exact tests were used for comparison of continuous and categorical variables, respectively. Univariate logistic regression was used to identify potential risk factors for BSI post CVC repair. Multiple breakages of the same CVC, and BSIs in overlapping observation periods of consecutive breakages are assumed independent.

Results
Sixty-four patients had 99 episodes of CVC breakage/repair in 68 CVCs. Median age (range) at repair was 2.5 (0.15–17.6) years. 48% of CVC breakages occurred in patients with solid tumors, 24% in HSCT recipients, and 19% in patients with leukemia. Only 25% of patients had neutropenia at repair and 14% had CVC occlusion 72 hours prior to breakage. All CVCs were made of silicone and 88% were double lumen external tunneled. First CVC breakage occurred at a median (range) of 130 (2–718) days since insertion, and CVCs were removed at a median (range) of 72.5 (3–753) days from the last repair. End of treatment was the most common cause (43%) for removal. The post-repair incidence of BSI was 4.5 per 1000 line-days compared with a pre-repair incidence of 4.3 (RR= 0.95, 95% CI 0.44, 2.18). There is no statistical difference between the characteristics of the pre-repair and post-repair BSI (Table 1). Figure 1 shows the organisms causing BSI before and after CVC repair. None of the evaluated variables was identified as a significant risk factor for BSI 30 days after CVC repair (Table 2).

Conclusion
Repair of CVC in pediatric oncology patients was not associated with increased risk of BSI.

Disclosures
All authors: No reported disclosures.
588. Are Popliteal Vein PICCs safe for Neonates?
Authors: Lochner Harold J , Rathore Mobeen H 
Published: October 2019

Abstract

Background
Peripherally inserted central catheters (PICCs) have been used as an alternative to central venous catheters ever since first described in 1975. Concerns were raised at our institution about safety of popliteal vein PICCs (P-PICCs) in neonates. There are no published data on the use of P-PICCs in neonates.

Methods
Retrospective review of records of all neonates admitted to an urban, 50-bed, level III Neonatal Intensive Care Unit between January 1, 2016 and December 31, 2018 who had PICCs placed. Records were reviewed for demographic data, number of days with PICC (dwell time), and complications. Complications included infectious such as bacteremia, insertion site infection; and mechanical such as occlusion, leakage, infiltration/edema, inadvertent dislodging, tip malposition, and catheter breakage. Chi-square (C), non-paired independent-samples t test (T), or Mann–Whitney U test (MW) was used for statistical analysis. IRB approval was obtained from University of Florida (teaching institution) and Baptist Health (patient location).

Results
830 PICCs inserted in 522 neonates were identified. 100 (12.0%) were P-PICCs and 730 (88.0%) were NP-PICCs. Of the NP-PICCs, 700/730 (95.8%) were placed in the upper extremities and 30/730 (4.1%) in the lower extremities. P-PICCs were placed in neonates with an average gestational age of 29 weeks vs. 32 weeks for NP-PICCs (P < 0.01, T) and P-PICCs were placed in neonates with average birthweight of 1,210 g vs. 1,840 g for NP-PICCs (P < 0.01, T). The average dwell time for P-PICCs was 15.4 days (range 2–79 days) compared with 14.2 days (range 0–109 days) for NP-PICCs (P = 0.22, MW). Infectious complications occurred in 5/100 (5.0%) of P-PICCs vs. 9/730 (1.23%) of NP-PICCs (P = 0.02, C) and mechanical complications in 13/100 (13%) P-PICCs vs. 75/730 (10.3%) in NP-PICCs (P = 0.39, C).

Conclusion
There was a significant increase in infectious complication rate between P-PICCs and NP-PICCs that necessitated PICC removal. There was a higher rate of complications overall with use of P-PICCs. This may be related to the increased proportion of lower birth weight and gestational age in the P-PICC group compared with the NP-PICC group. We intend to increase the patient numbers by adding data from 2019. Based on our review P-PICCs have increased risk of infectious complication and may not be as safe.

Disclosures
All authors: No reported disclosures.
589. Impact of Parents and the Environment on MRSA Transmission in the Neonatal ICU
Authors: Reich Patrick J , Boyle Mary G , Hogan Patrick G , Gu Hongjie , Xu Yanping , Andersen Heidi , Thompson Ryley , Muenks Carol , Sullivan Melanie , Burnham Carey-Ann D , Haslam David , Fritz Stephanie 
Published: October 2019

Abstract

Background
Methicillin-resistant Staphylococcus aureus (MRSA) colonization predisposes Neonatal Intensive Care Unit (NICU) infants to subsequent infection. Reservoirs for acquisition remain poorly understood, limiting infection prevention efforts to prevent transmission.

Methods
Infants with known MRSA nasal colonization based on hospital surveillance and controls with negative MRSA screening cultures, and their parents, were enrolled in a prospective cohort study. Weekly cultures were collected from infants (4 sites), parents (3 sites), and NICU environmental surfaces (5 sites). Factors associated with MRSA colonization and infection were identified using generalized linear mixed modeling. Whole-genome sequencing (WGS) and pairwise comparisons were performed across entire genomes on 1041 S. aureus isolates using kSNP3. Isolates differing by less than 80 single nucleotide polymorphisms were considered highly related; highly related strains from different sources suggested transmission.

Results
Samples were collected 1–28 (median 7) times from 29 MRSA-colonized infants, 29 controls, 49 mothers, and 21 fathers. Over the study period MRSA colonization was detected in 10 (34%) infants who were not known to be MRSA-colonized based on hospital nasal surveillance cultures. Parent MRSA colonization (OR=11.0; 95% CI: 2.2, 55.0) and environmental MRSA contamination (OR=5.0; 95% CI: 1.6, 15.3) were associated with infant MRSA colonization. Specifically, 87% of infants with an MRSA-colonized parent were MRSA-colonized. MRSA infections occurred in 6 (21%) MRSA-colonized infants and 0 controls (P = 0.05). Infant rectal colonization (OR=15.0; 95% CI 1.6, 140.5) and persistent MRSA colonization (i.e., 3 or more consecutive positive MRSA cultures) (OR=8.4; 95% CI 1.3, 52.5) were associated with MRSA infection. Thirty clusters of highly related isolates were detected, including 12 clusters with highly related isolates from multiple study families (2–6 [median 3] unique families per cluster; Figures 1 and 2).

Conclusion
Our findings suggest MRSA transmission between infants, their parents, and the environment as well as transmission between patients. Future infection prevention efforts should consider parent and environmental reservoirs, as well as the role of extranasal sites of colonization.

Disclosures
All authors: No reported disclosures.
595. Intranasal Mupirocin with Chlorhexidine Bathing has Limited Effectiveness for MRSA Decolonization among Neonates
Authors: Mazade Marc A , Mattern Anne 
Published: October 2019

Abstract

Background
MRSA colonization is a common neonatal problem and is associated with invasive infection. Good hand-washing and contact precautions reduce transmission. However, long-term contact isolation, sometimes for months, causes dissatisfaction among neonatal intensive care unit (NICU) care providers and parents. We examined the effectiveness of MRSA decolonization among neonates over 3 years.

Methods
Our NICU patients are routinely screened for MRSA colonization by PCR testing of nasal and rectal swabs upon admission and every 2 weeks. Patients with a history of MRSA infection or colonization became eligible for MRSA eradication upon reaching 2000g. Our protocol included intranasal muporocin 2% ointment applied to both nares twice daily for 5 days and 2% chlorhexidine wipe bath daily for 7 days. Wipes were used for bathing from the neck down for at least 20 sec per wipe. Two wipes were used for patient’s < 10 kg with the first wipe being used on the neck, chest, arms, and back, and the second wipe being used on the legs, buttocks, and perineum. Patients were excluded from chlorhexidine bathing if they had a known allergy, were < 27 weeks gestation, < 1 week chronological age, receiving phototherapy, or had severe skin disease, open wounds, or burns. Contact isolation was discontinued if 2 sets of nares and rectal PCR swabs 5 days apart were negative and the patient had not been on antibiotics during the screening period. Surveillance MRSA PCR testing continued. Contact isolation was to be re-initiated if subsequent MRSA screening was positive. Patients were not decolonized a second time.

Results
Among infants admitted to the NICU during from 2016 to 2018 MRSA colonization was identified in 102 patients. Fifty-six were noted to have colonization present on admission and 46 were acquired on or after hospital day 3. The decolonization protocol with follow-up screening was completed in 33 infants. Successful decolonization was achieved for only 5 (15%) of infants. There were no adverse reactions noted among neonates and no MRSA decolonized patients reverted to positive by PCR screening while in hospital.

Conclusion
85% of neonates with MRSA failed decolonization. Using mupirocin intranasally and chlorhexidine bathing to decolonize neonates with MRSA was welcomed by staff and families, but was poorly effective.

Disclosures
All authors: No reported disclosures.
597. Cross-resistance of Ceftolozane-Tazobactam and Imipenem-Relebactam Against Clinical P. aeruginosa Isolates: SMART United States 2016–2018
Authors: Lob Sibylle , Kazmierczak Krystyna , DePestel Daryl , Raddatz Janet , Young Katherine , Motyl Mary , Sahm Daniel F 
Published: October 2019

Abstract

Background
Ceftolozane-tazobactam (C/T) is an antipseudomonal cephalosporin combined with a β-lactamase inhibitor. The combination was cleared by FDA and EMA and is approved in the United States and over 60 countries worldwide. Relebactam (REL) is an inhibitor of class A and C β-lactamases that is in clinical development in combination with imipenem (IMI). Using clinical isolates collected in the United States as part of the global SMART surveillance program, we compared the activity of C/T and IMI/REL against P. aeruginosa (PA) isolates.

Methods
In 2016–2018, 29 clinical laboratories from the United States collected up to 250 consecutive, aerobic or facultatively anaerobic, gram-negative pathogens (GNP) from blood, intra-abdominal, urinary, and lower respiratory tract infections. A total of 14,606 GNP were collected, of which 2,774 were PA. MICs were determined using CLSI broth microdilution and interpreted with CLSI 2019 breakpoints; IMI breakpoints were used for IMI/REL.

Results
The activity of C/T and IMI/REL against 2,774 PA is shown (table). Among all PA, 1.8% of isolates were nonsusceptible (NS) to both agents; 4.4% were susceptible (S) to C/T but not to IMI/REL, and 2.9% were susceptible to IMI/REL but not to C/T. Among the subset of isolates collected from patients in ICUs (n = 827), 87.3% were susceptible to both C/T and IMI/REL, 2.7% were nonsusceptible to both agents, 5.8% of isolates were susceptible only to C/T, and 4.2% of isolates were susceptible only to IMI/REL. Among all C/T-NS isolates (all patient locations, n = 132), 61.4% were IMI/REL-S and <30% were susceptible to all other studied β-lactams and fluoroquinolones. Among all IMI/REL-NS isolates (n = 173), 70.5% were C/T-S and <36% were susceptible to all other studied β-lactams and fluoroquinolones. Of the tested agents, only amikacin and colistin exceeded the activity of C/T or IMI/REL against these NS subsets.

Conclusion
Resistance to C/T or IMI/REL was not common among recent clinical isolates of PA collected in the United States, and both agents promise to be important treatment options. A significant proportion of isolates nonsusceptible to one agent was susceptible to the other, especially among isolates from patients in ICUs. The data suggest that susceptibility to both agents should be tested at hospitals.

Disclosures
All authors: No reported disclosures.
603. Identification of a Carbapenemase-Producing, Extensively Drug-Resistant Klebsiella pneumoniae Isolate Carrying a blaNDM-1-Bearing, Hypervirulent Plasmid, United States 2017
Authors: Stanton Richard A , McAllister Gillian A , Bhatnagar Amelia , Karlsson Maria , Brown Allison C , Rasheed James , Elkins Christopher , Halpin Alison L 
Published: October 2019

Abstract

Background
The recent discovery of carbapenemase-producing hypervirulent Klebsiella pneumoniae (CP-HvKP) has signaled the convergence of multidrug resistance and pathogenicity, with the potential for increased mortality. While previous studies of CP-HvKP isolates revealed that most carried carbapenemase genes and hypervirulence elements on separate plasmids, a 2018 report from China confirmed that both could be harbored on a single, hybrid carbapenemase-hypervirulent plasmid. As part of a project sequencing isolates carrying multiple carbapenemase genes identified through CDC’s Antibiotic Resistance Laboratory Network (AR Lab Network), we discovered a blaNDM-1-bearing hypervirulent plasmid found in a KPC- and NDM-positive K. pneumoniae from the United States.

Methods
Antimicrobial susceptibility testing (AST) was performed by reference broth microdilution against 23 agents. Whole-genome sequencing (WGS) was performed on Illumina MiSeq and PacBio RS II platforms.

Results
AST results indicated the isolate was extensively drug-resistant, as it was non-susceptible to at least one agent in all but two drug classes; it was susceptible to only tigecycline and tetracycline. Analysis of WGS data showed the isolate was ST11, the same sequence type that caused a fatal outbreak of CP-HvKP in China in 2016. The genome included two plasmids. The smaller one (129kbp) carried seven antibiotic resistance (AR) genes, including the carbapenemase gene blaKPC-2. The larger plasmid (354kbp) harbored 11 AR genes, including the metallo-β-lactamase gene blaNDM-1, as well as virulence factors iucABCD/iutA, peg-344, rmpA, and rmpA2, which comprise four of the five genes previously identified as predictors of hypervirulence in K. pneumoniae.

Conclusion
This is the first report of a hybrid carbapenemase-hypervirulent plasmid in the United States. The presence of both blaNDM-1 and hypervirulence elements on the same plasmid suggests that the CP-Hv pathotype could spread rapidly through horizontal transfer. This discovery demonstrates the critical role of genomic characterization of emerging resistance and virulence phenotypes by the AR Lab Network as part of US containment efforts.

Disclosures
All authors: No reported disclosures.
604. Gram-Negative Bacilli Carrying Multiple Carbapenemases: the United States, 2012–2018
Authors: Ham David , Mahon Garrett , Bhaurla Sandeep , Horwich-Scholefield Sam , Klein Liore , Dotson Nychie , Rasheed James , Huang Jennifer , Brown Allison C , Kallen Alexander , Walters Maroya S 
Published: October 2019

Abstract

Background
Gram-negative bacilli carrying multiple carbapenemase genes (multi-CP-GNB) present an emerging public health threat; to date, most isolates reported in the literature have been from outside the United States. We reviewed multi-CP-GNB reported to CDC.

Methods
Reports of multi-CP-GNB isolates carrying genes encoding >1 targeted carbapenemases (i.e., KPC, NDM, OXA-48-type, VIM, or IMP) were received from healthcare facilities, health departments, and public health laboratories, and included isolates tested through the AR Laboratory Network (ARLN) beginning in 2017 as well as isolates sent to CDC for reference testing. Epidemiologic data were gathered by health departments during public health investigations.

Results
From October 2012 to November 2018, 111 multi-CP-GNB isolates from 71 patients in 20 states were identified. Two patients had three different multi-CP-GNB and one patient had two different multi-CP-GNB. The majority of cases (76%) were reported in 2017 or later, after ARLN testing began. Among patients with multi-CP-GNB, the most common organism-mechanisms combination was Klebsiella pneumoniae carrying NDM and OXA-48-type enzymes (table). Urine (44%) and rectal (20%) were the most frequent specimen sources for isolates. The median age of patients was 63 years (range 2–89 years); most had specimens collected at acute care hospitals (87%) or post-acute care facilities (9%). Of 50 patients with information available, 37 traveled internationally in the 12 months prior to culture collection. Among these, 88% were hospitalized for ≥1 night while outside the United States with 10 countries reported, of which India was most common (n = 18). All 5 patients with Pseudomonas aeruginosa co-carrying carbapenemases reported recent hospitalization outside the United States.

Conclusion
The multi-CP-GNB reported to CDC include diverse organisms and carbapenemase combinations and often harbored carbapenemases from different β-lactamase classes, which may severely limit treatment options. Healthcare exposures outside the United States were common; providers should ask about this exposure at healthcare admission and, when present, institute interventions to stop transmission in order to slow further US emergence.

Disclosures
All authors: No reported disclosures.
646. Evaluation of the Utility of a New Comprehensive Molecular Assay to Test for the Common Pathogens that Cause Lower Respiratory Tract Infections and its Potential Impact on Antibiotic Therapy
Authors: Tarro Thomas M , Bulter-Wu Susan , Kovacs Andrea , Cielo Mikhaela 
Published: October 2019

Abstract

Background
Lower respiratory tract infection (LRTI) has high mortality among critically ill patients. The current standard of care for diagnosing bacterial causes of LRTI is respiratory culture, which is time consuming and insensitive. The FilmArray Pneumonia Panel (FA-Pneumo) (Biofire Diagnostics, Salt Lake City, UT) is FDA-cleared for the detection of lower respiratory tract pathogens (bacteria, atypical bacteria, and viruses) directly from lower respiratory tract specimens. Here, we evaluated the performance of the FA-Pneumo assay in bronchoalveolar lavage (BAL) samples and assessed its potential impact on antibiotic therapy.

Methods
A total of 61 BAL samples collected for respiratory culture from intensive care unit patients aged 18 years and older who had symptoms consistent with LRTI were included in the study. Remnant BAL samples were tested using the FA-Pneumo and results were compared with standard of care respiratory culture results. We then conducted a chart review to determine the potential impact of FA-Pneumo results on antibiotic therapy.

Results
The results of 48 out of 61 BAL samples (78.7%) were the same when comparing FA-Pneumo with a standard of care respiratory culture. Two patients grew Stenotrophomonas maltophilia and 1 patient grew Achromobacter. Importantly, neither of these organisms is targeted by the FA-Pneumo assay. Three patients (4.9%) had viral LRTI, with 9 patients (14.8%) having bacterial/viral co-infection. A total of six patients with methicillin-susceptible Staphylococcus aureus (MSSA) remained on vancomycin therapy for a median of 1.5 days (range 0–7 days) and all three patients with viral LRTI remained on broad-spectrum antibiotic therapy for a median of 4 days (range 3–13 days). All three patients with ESBL-positive Enterobacteriaceae detected by FA-Pneumo and culture were not started on appropriate antibiotic therapy until >48 hours after the FA-Pneumo would have been resulted.

Conclusion
The FA-Pneumo assay has the potential to lead to earlier discontinuation of vancomycin for patients with MSSA LRTI and earlier broadening of therapy for ESBL LRTI. Providers should be aware of the inability of the FA-Pneumo to detect S. maltophilia and Achromobacter species.

Disclosures
All authors: No reported disclosures.