bluuebunny/crossref_metadata_2025_split huggingface dataset:
2405. Clinical Characteristics and Prognostic Factors for Extraintestinal Infection Caused by Clostridium difficile: An Analysis of 62 Consecutive Cases
Authors: Chung Hyemin , Cho Eunbeen , Bae Seongman , Jae Kim Min , Pil Chong Yong , Lee Sang-Oh , Soo Kim Yang , Hee Woo Jun , Kim Sung-Han , Choi Sang-Ho 
Published: October 2019

Abstract

Background
Whereas Clostridium difficile enterocolitis has been well studied, data regarding extraintestinal C. difficile infection remain scarce and anecdotal. We investigated characteristics and prognostic factors in patients with extraintestinal C. difficile infection at a large university hospital over a recent 20-year period.

Methods
We conducted a retrospective cohort study of patients at a 2,700-bed tertiary care hospital from January 1997 through December 2018 whose extraintestinal clinical specimen revealed C. difficile. Gastrointestinal (GI) disruption was defined as compromised integrity of the GI tract by abdominal surgery, perforation, malignancy, or bleeding. Patients were divided into 3 groups: group A (GI disruption with malignancy, n = 15); group B (GI disruption without malignancy, n = 23); group C (No GI disruption or malignancy, n = 24). The main outcome was 30-day all-cause mortality.

Results
A total of 62 patients were enrolled, and the incidence of extraintestinal C. difficile infection was 2.81 per 100,000 admissions. Median age was 56 years and 36 (58.1%) of the patients were men. Seven patients (11.3%) had confirmed C. difficile enterocolitis, and 38 patients (61.3%) had a polymicrobial infection. C. difficile bacteremia was identified in 22 patients (35.5%) and was significantly more common in group A (60.0% [9/15]) than groups B (43.5% [10/23]) or C (12.5% [3/24]) (P = 0.01). Thirty-day mortality rates were also significantly higher in group A than groups B or C (60.0% [9/15] vs. 13.0% [3/23] and 16.7% [4/24], respectively; P < 0.001) (Figure 1). C. difficile bacteremia (P = 0.16), polymicrobial infection (P = 0.91), and antimicrobial therapy for C. difficile (P = 0.48) were not significantly associated with 30-day mortality. In a multivariate analysis, group A was an independent risk factor for 30-day mortality. (adjusted odds ratio; 7.29 [95% confidence interval; 1.68–31.68], P = 0.01).

Conclusion
Extraintestinal C. difficile infection was not commonly associated with C. difficile enterocolitis. Extraintestinal C. difficile infection accompanied by GI disruption with malignancy was associated with significantly poorer outcomes.

Disclosures
All authors: No reported disclosures.
2430. Comorbidity and Severity of Illness Risk Adjustment for Hospital-Onset Clostridioides difficile Infection
Authors: Cabral Stephanie , Nadimpalli Gita , Thom Kerri , Leekha Surbhi , Harris Lisa , Blanco Herrera Natalia , Harris Anthony 
Published: October 2019

Abstract

Background
Hospital-onset C. difficile infection (HO-CDI) rates are publicly reported. However, patient-level risk factors are not included in the current risk adjustment methodology, and the knowledge as to which risk factors to include is incomplete. This study aimed to determine whether electronically-available comorbidities and laboratory indicators of severity of illness are risk factors for HO-CDI.

Methods
We performed a retrospective cohort study of all adult patients admitted to three hospitals (one academic, two community) in Baltimore, Maryland between January 1, 2016 and January 1, 2018. Information extracted from electronic medical records included demographics, ICD-10 codes, laboratory results within 24 hours of admission (i.e., hematocrit, hemoglobin, platelet count, leukocytes, BUN, CO2, creatinine, glucose, sodium, and potassium), medication administration (i.e., antibiotic and antacid use), and C. difficile test result. Comorbid conditions were assessed by the Elixhauser Comorbidity Index components. HO-CDI was defined by positive laboratory test > 3 days after admission. Potential risk factors for HO-CDI were assessed using bivariate log binomial regression. Multivariable log binomial regression was conducted using significant (P < 0.1) covariates.

Results
At hospital 1 (academic), 314 of the 48,057 (0.65%) eligible patient admissions had HO- CDI; 41 of the 8,791 (0.47%) and 75 of the 29,211 (0.26%) of patient admissions at community hospitals 2 and 3, respectively, had HO-CDI. In multivariable analysis, Elixhauser Score was a significant risk factor for HO-CDI at all hospitals when controlling for antibiotic and antacid use; for every one-point increase in Elixhauser Score, there was an increased risk of HO-CDI of 1.27 (95% CI: 1.21, 1.32) at hospital 1, 1.38 (95% CI: 1.24, 1.54) at hospital 2, and 1.28 (95% CI: 1.10, 1.31) at hospital 3. Table 1 shows significant risk factors for HO-CDI for each hospital. When individual comorbidities were assessed in the regression analysis, fluid and electrolyte disorders were a significant risk factor for HO-CDI for all hospitals.

Conclusion
Laboratory values upon admission and electronically available patient comorbidities are important risk factors for HO-CDI and should be considered for future risk adjustment.

Disclosures
All authors: No reported disclosures.
2438. Using Artificial Neural Networks to Predict Intra-Abdominal Abscess Risk Post-Appendectomy
Authors: Al Khatib Hassan S , Alramadhan Morouge , Murphy James , Tsao KuoJen , Chang Michael L 
Published: October 2019

Abstract

Background
Applying Artificial Intelligence techniques to healthcare data are gaining momentum. Early identification of patients at risk of surgical site infections is a major clinical goal. Our objective for this study was to determine whether deep learning AI techniques could identify patients at risk of intra-abdominal abscess development post-appendectomy using clinical data for pediatric patients undergoing appendectomy.

Methods
A dataset of 1,574 patients classified by surgeons as negative (1,328) or positive (246) for Intra-Abdominal Abscess Post-Appendectomy for Appendicitis were selected from a database containing 6,127 patients less than 19 years-old who had appendectomy at our institution between 2009–2018. Demographic, clinical, and surgical information were extracted. 34 Independent variables were identified to be useful for the study. Using Random Forest methodology 12 variables with the highest influence on the outcome were selected for the final dataset. Data imputation (MICE algorithm) was used to replace missing data points. Two “Reproducible” Artificial Neural Networks with different architectures were developed to predict the risk of developing Intra-Abdominal Abscess Post- Appendectomy: Model (1) 12 Inputs, 3 hidden layers with 12 Neurons each, and 1 Output. Model (2) 12 Inputs, 2 hidden layers with 18 Neurons each, and 1 Output.

Results
For the 1,574 patients (80%-20% used as training and test sets), Model (1) achieved Accuracy of 89.84%, Sensitivity of ~ 70%, and Specificity of 93.61% on the test set while Model (2) achieved Accuracy of 84.13%, Sensitivity of 81.63%, and Specificity of 84.6%. The difference between the models is that in Model (2) we over sampled the minority class (using SMOTE algorithm) to balance both classes which helped the model to learn both classes without bias and improved sensitivity over Model (1).

Conclusion
Deep learning algorithms applied to enough clinical variables can identify patients with high probability for the risk of developing intra-abdominal abscess post-appendectomy. While further test sets are necessary to validate the models, Artificial Neural Networks can be an important addition to current post-surgical care guidelines to personalize and optimize care to reduce infections following appendectomy.

Disclosures
All authors: No reported disclosures.
2454. A Cluster of Gram-Negative Bloodstream Infections in Connecticut Hemodialysis Patients Associated with Contaminated Wall Boxes and Priming Buckets
Authors: Backman Lauren , Dumigan Diane G , Harizaj Adora , Oleksiw Marylee , Carusillo Evelyn , Malo Sue , Ransom Acacia , Patel Priti , Nguyen Duc , Moulton-Meissner Heather , Boyce John M 
Published: October 2019

Abstract

Background
Patients requiring maintenance hemodialysis (HD) are at increased risk of bloodstream infections. We investigated a cluster of infections due to unusual Gram-negative bacilli that affected patients undergoing HD at an outpatient unit with 19 stations (Clinic A).

Methods
A case was defined as a HD patient at Clinic A with >1 blood or urine culture positive for Delftia acidovorans, Enterobacter absuriae, or Burkholderia cepacia during the period February 1 – April 30, 2018. An investigation included review of patient records, facility policies, practice observation, environmental cultures, and a 1:4 case–control study. Controls were patients without bloodstream infection (BSI) during the outbreak period.

Results
The cluster included 3 patients. Patient 1 had BSI due to D. acidovorans (2/08), E. absuriae (3/15) and B. cepacia (3/17). Patient 2 had BSI due to D. acidovorans (3/17 and 3/27) and S. maltophilia (4/5). Patient 3 had a urine culture positive for D. acidovorans and S. maltophilia (4/2). The case–control study showed that cases had been dialyzed more often than controls on the third shift (P < 0.0001) and at station 2 (P < 0.0001), where subsequently a wall box spent dialysate drain connection swab culture yielded D. acidovorans. E. absuriae was recovered from wall boxes and spent dialysate drain connection at two stations and from used prime buckets from two stations; one wall box culture grew S. maltophilia. D. acidovorans and E. absuriae patient isolates were not available for genomic analysis. Observations revealed that waste water was leaking onto the floor from several wall boxes, and that priming buckets were often rinsed with tap water after being disinfected with 1:100 bleach solution and not allowed to dry before reuse. Multiple deficiencies in hand hygiene and station disinfection were observed. No deficiencies in water treatment practices were identified. Multiple water cultures obtained in August were negative for the observed pathogens.

Conclusion
A cluster of unusual Gram-negative infections in outpatient HD patients was most likely due to exposures to contaminated wall boxes or priming buckets; poor hand hygiene and station disinfection can contribute to transmission to patients.

Disclosures
All authors: No reported disclosures.
2457. Data Science for Outbreak Investigation: Identifying Risk Factors, Tracing Contacts, and Eliciting Transmission Pathways in a Vancomycin-Resistant Enterococci (VRE) Outbreak
Authors: Zahnd Stefan , Hossmann Theus , Atkinson Andrew , Herbel Sabine , Salazar-Vizcaya Luisa , Dahlweid Michael , Marschall Jonas 
Published: October 2019

Abstract

Background
In 2018 we experienced a nosocomial outbreak due to vancomycin-resistant enterococci (VRE) in our hospital network. Our goals were to characterize risk factors for VRE acquisition, elicit potential hot spots of transmission, and delineate an optimized approach to tracing contacts.

Methods
We assembled diverse datasets of variable quality and covering different aspects of care from electronic medical records generated during the outbreak period (1/2018–9/2018). Patients who tested VRE-positive during this period were compared with controls with up to 3 negative screenings. First, we identified risk factors for VRE colonization by means of uni- and multivariate analyses. Next, we elicited transmission pathways by detecting commonalities between VRE cases, and determined whether patients with characteristics and connections similar to VRE cases were missed by our current contact tracing strategy.

Results
We compared 221 VRE patients to 33,624 controls. Independent predictors of VRE colonization were ICU admission (OR 4.9, with 95% confidence interval [3.7–6.5], P < 0.001)], number of records in the database (a proxy for severity-of-illness, OR 1.1 [1.1–1.1], P < 0.001), length of hospital stay (OR 2.7 [2.0–3.5], P < 0.001), age (OR 1.3 [1.2–1.4], P < 0.001), and weeks of antibiotics (OR 1.2 [1.1–1.3], P < 0.001). By using complex network analysis, we were able to establish three main pathways by which the 221 VRE cases are connected: healthcare personnel, medical devices, and patient rooms. This multi-dimensional network extends beyond our current contact tracing strategy, which captures inpatients based on geographical proximity (cf. figure).

Conclusion
In this outbreak investigation based on a large electronic healthcare data collection, we found three main risk factors for being a VRE carrier (ICU admission, length of hospital stay, antibiotic exposure), along with three important links between VRE cases (healthcare personnel, medical devices, patient rooms). Data science is likely to provide a better understanding of outbreaks, but interpretations should take data maturity, the scope of included sources, and potential confounding factors into account.

Disclosures
All authors: No reported disclosures.
2461. Community-Acquired in Name Only: A Cluster of Carbapenem-Resistant Acinetobacter baumannii in a Burn Intensive Care Unit
Authors: Shenoy Erica S , Pierce Virginia M , Sater Mohamad , Pangestu Febriana , Herriott Ian , Fred Hawkins , Suslak Dolores , West Lauren R , Huntley Miriam , Rosenberg David C 
Published: October 2019

Abstract

Background
Detection of nosocomial outbreaks often relies on epidemiological definitions of community and nosocomial acquisition. We report a cluster of three carbapenem-resistant Acinetobacter baumannii (CRAB) infections linked to a single source patient with infections occurring within 2 days of admission to a burn intensive care unit (ICU). The epidemiological investigation was supplemented by whole-genome sequencing (WGS) of clinical and environmental isolates.

Methods
Study participants included burn ICU patients identified with infections caused by CRAB. A detailed review of patient demographic and clinical data was conducted. Clinical A. baumannii isolates were assessed by antimicrobial susceptibility testing and WGS. Review of infection control practices on the affected unit was followed by environmental sampling. A. baumannii isolates obtained through environmental sampling were assessed for carbapenem resistance and then underwent WGS for comparison to the clinical isolates.

Results
Three cases of CRAB infection in the affected unit spanning a period of 3 months were linked to a preceding source patient, with CRAB isolates from the four patients differing by 5–7 single nucleotide variations. All case patients had been admitted to the same room within 2 days before development of CRAB infection. Environmental sampling performed while the third case patient occupied the room identified highly contaminated areas, and environmental CRAB isolates linked the patient isolates. The contaminated areas were subsequently re-sampled after enhanced terminal cleaning of the room. No additional CRAB was isolated, but other pathogenic organisms were recovered.

Conclusion
We report a cluster of three infections caused by highly resistant A. baumannii that occurred in a burn intensive care unit over a period of 3 months, linked to a single source patient. Three case patients developed infections classified as community-acquired using standard epidemiological definitions, however, whole-genome sequencing revealed clonality. An extensive investigation identified the role of environmental reservoirs. Burn patients may be particularly vulnerable to early-onset nosocomial infection from environmental contamination.

Disclosures
All authors: No reported disclosures.
2478. Surveillance of antibacterial resistance among clinical isolates from hospitals in Shanghai: results of 2018
Authors: Yang Yang , Guo Yan , Zhu Demei , Hu Fupin 
Published: October 2019

Abstract

Background
To investigate the current state of antibacterial resistance of clinical isolates from hospitals in Shanghai, China.

Methods
Antimicrobial susceptibility testing (AST) was carried out for the clinical isolates from 50 hospitals (including 30 grade A tertiary hospitals and 20 grade B tertiary hospitals/grade A secondary hospitals, and there were 3 children hospitals among them) according to a unified protocol using Kirby–Bauer(KB) method or automated AST systems. Results were analyzed according to CLSI 2018 breakpoints.

Results
Of the 144373 clinical isolates, Gram-positive cocci and Gram-negative bacilli accounted for 29.6% and 70.4%, respectively. The overall prevalence of MRSA in Staphylococcus aureus was 45.9% and 78.4% for MRCNS in coagulase-negative Staphylococcus. No strains were found resistant to vancomycin in Staphylococcus spp. 84.1% of the 1204 strains of non-meningitis S. pneumoniae isolated from children were penicillin-susceptible (PSSP), 15.9% were penicillin-nonsusceptible, including penicillin-intermediate (PISP, 10.5%) and penicillin-resistant (PRSP, 5.4%) strains. Of the 361 strains isolated from adults, 94.5%, 3.0% and 2.5% were PSSP, PISP, and PRSP, respectively. Vacomycin-resistance E. feacium was 0.7% and no vacomycin-resistant E. feacalis were identified. According to PCR results, most of these resistant strains were vanA genotype. The prevalence linezolid-nonsusceptible E. faecalis was about 1.6%, few E. feacium was resistant to Linezolid. The overall prevalence of ESBL-producing strains was 54.0% in E. coli, 35.0% in Klebsiella pneumoniae and 47.1% in Proteus mirabilis. Enterobacteriaceae isolates were still mainly susceptible to carbapenems. Overall, 11.7% and 11.2% of the Enterobacteriaceae isolates were resistant to imipenem and meropenem, respectively. The predominant organism of CRE isolates was K. pneumoniae. The prevalence of CRAB and CRPA were 62.5% and 28.7%, respectively.

Conclusion
Antimicrobial resistance remains to be a problematic issue in healthcare settings, especially in Gram-negative bacilli, effective infection-control measures should be promoted to tackle this critical threat.

Disclosures
All authors: No reported disclosures.
142. Mean Platelet Volume Is Associated with Embolic Events of Infectious Endocarditis
Authors: Barnes Erin W 
Published: October 2019

Abstract

Background
Increased mean platelet volume (MPV) is a marker of more active and rapidly aggregating platelets. There is limited evidence that increased MPV is associated with more embolic disease in infectious endocarditis (IE). This study seeks to validate this relationship and assess for effect modification by injection drug use.

Methods
Records of all patients aged ≥18 admitted to Wake Forest Baptist Medical Center (WFBMC) from January 1, 2004 to September 30, 2015 with an ICD-9 code for IE and without a simultaneous ICD-9 code indicating”mechanical complication of cardiac device, implant and graft’ were reviewed. Inclusion criteria consisted of possible or definite IE by modified Duke criteria and labs drawn within 24 hours of presentation. Univariate analyses were assessed by Chi-square, Fisher’s exact test, Mann–Whitney U, and Student’s t-test. Multiple logistic regression assessed the association between MPV and embolic phenomena while controlling for potential confounders.

Results
A total of 237 cases (80 IDU-IE and 157 non-IDU IE) met criteria for analysis suffering 115 (48.5%) embolic events to the brain and/or lungs (41.4% in non-IDU vs. 62.5% in IDU-IE, P = 0.002). MPV (P < 0.0001) and drug use (P = 0.002) were significantly associated with embolic disease. S aureus involvement (P = 0.0002), vegetation ≥1 cm (P = 0.009), atrial fibrillation (P = 0.05), hypertension (P = 0.05), age (P = 0.0008), presenting hospital location (P = 0.001), total platelets (P < 0.0001), age-unadjusted Charleson comorbidity score (P = 0.001), and left-sided valve vegetation (P = 0.006) were also significantly associated while gender, white blood cell count, creatinine and albumin were not. MPV remained significantly associated with embolic disease in the fully adjusted model with OR 1.4, 95% CI [1.1–1.7]. Vegetation ≥1 cm (OR 2.4, 95% CI [1.2–4.7]), left-sided valve vegetation (OR 0.4, 95% CI [0.2–0.8]) and direct presentation rather than transfer to WFBMC (OR 0.4, 95% CI [0.2–0.8]) also remained significant. There was no evidence of an interaction between MPV and drug use nor evidence of effect modification when the analysis was stratified by drug use status.

Conclusion
Increased MPV is significantly associated with embolic disease of IE even when additional covariates are taken into consideration.

Disclosures
All authors: No reported disclosures.
2497. Women’s Perspectives on and Experiences with Long-acting Injectable Anti-retroviral Therapy in the United States and Spain: the Potential Role of Gender in Patient Preferences
Authors: Mantsios Andrea R , Murray Miranda , Karver Tahilin Sanchez , Davis Wendy , Margolis David , Kumar Princy , Swindells Susan , Bredeek Fritz , Deltoro Miguel García , García Rafael Rubio , Antela Antonio , Garris Cindy , Shaefer Mark S , Gomis Santiago Cenoz , Bernaldez Miguel Pascual , Kerrigan Deanna 
Published: October 2019

Abstract

Background
Adherence to antiretroviral therapy (ART) to treat HIV remains a critical global health challenge given its relationship with individual health outcomes and population-level transmission. Given barriers associated with oral ART adherence, and considerations of patients’ preferences, long-acting injectable (LA) ART (cabotegravir + rilpivirine) is under development and has been shown to be non-inferior to daily oral ART in Phase III trials. While most of the trial participants have been men, as LA ART gets closer to becoming available for routine clinical use, it is critical to understand how this option is perceived by women.

Methods
We conducted in-depth interviews with 67 individuals, 53 people living with HIV (PLHIV) and 14 healthcare providers, in 11 sites in the United States and Spain participating in Phase III LA ART trials (ATLAS, ATLAS 2-M and FLAIR). Twenty percent (10/53) of trial participants interviewed were women. Interviews explored patient and provider perspectives and experiences with LA ART, and appropriate candidates and recommendations to support use. Interviews were audio-recorded, transcribed and coded using thematic content analysis.

Results
Overall, several salient themes emerged regarding participant’s generally positive experiences transitioning from daily oral ART to injectable ART including: the importance of the clinical efficacy of LA ART, the ability to learn to manage injection side-effects over time, and the “freedom” reportedly afforded by LA ART logistically and psychosocially. Women interviewed shared many of the aforementioned positive perceptions of LA ART but also had some unique perspectives. Female participants discussed how LA ART was easier to integrate into their daily lives including managing their multiple roles and responsibilities, which often involved working full-time and taking care of themselves as well as their family and children.

Conclusion
Similar to all participants, female participants had generally positive views of LA ART. However, the gendered nature of their daily lives also led to some unique perspectives on why and how they were satisfied with LA ART that merits further exploration in future research.

Disclosures
All authors: No reported disclosures.