bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-288. High Prevalence of Carbapenem-Resistant Gram-Negative Bacteria Among ICU Patients in a Tertiary-Care Hospital
Authors: Protonotariou Efthymia , Meletis George , Tychala Areti , Sereni Zoe , Trikoupis Petros , Oikonomou Margarita , Amoiridou Pinelopi , Rizopoulos Rizos , Tampakas Lampros , Pantelidou Parthenopi , Efthymiou Aikaterini , Argiriadou Elena , Mantzana Paraskevi , Skoura Lemonia 
Published: January 2025

Abstract

Background
Infections by carbapenem-resistant organisms (CROs) are causing worldwide concern. Some Gram-negative CROs may act as colonizers of the intestinal flora. Starting from colonization, they may develop serious infections to their host under favorable circumstances. In the present study, the data of patients hospitalized in the Intensive Care Unit (ICU) of AHEPA University Hospital regarding their surveillance rectal detection for carbapenem-resistant Enterobacterales, Pseudomonas aeruginosa and Acinetobacter baumannii was reviewed.

Methods
From October 2022 to December 2023, 578 individual patients’ surveillance rectal specimens were evaluated using the chromogenic BrillianceTMCRE Agar (Oxoid, UK). Moreover, among recovered Enterobacterales and P. aeruginosa isolates, carbapenemase production was investigated using the NG-Test CARBA 5 multiplex immunoassay (NG-Biotech, France).

Results
Among the 578 patients evaluated, 178 (30.8%) were colonized with at least one and 68 (38%) with more than one carbapenem-resistant microorganism (Table 1). In total, 303 CROs were identified. Klebsiella pneumoniae was present in most samples (n=134); 119/ 134 were found carbapenemase-producers with KPC being the most frequent (n=46) enzyme identified. A. baumannii (n=110) followed in order of pathogen detection. 57 carbapenem-resistant P. aeruginosa isolates were also recovered and 45 of them were found positive for metallo-β-lactamase production (VIM or NDM) (Figure 1). 115 (64.6%) of the colonized patients were male and 63 (35.4%) were female. Mortality rate for men was 60.87% with an average age of 62 years, while for women it was 72.58% with an average age of 67 years (Figure 2).

Conclusion
Our study highlights the high prevalence of carbapenem-resistant bacteria in ICU patients in our hospital, with a significant proportion of patients being colonized with these organisms. Additionally, the identification of the most common carbapenemase-producing pathogens as well as the high mortality rates among colonized patients provides valuable information for guiding treatment strategies and improving patient outcomes.

Disclosures
All Authors: No reported disclosures
P-292. Epidemiology of Escherichia coli from Urine Sources at Three U.S. Sites, August 2023
Authors: Brandenburg Joshua M , Grass Julian E , Che Looi Hsioa , Tellerman Julia , Dietz Jenna , Rebolledo Paulina , Smith Gillian , Jacob Jesse T , Parker Erin , Longson Rebecca , Guh Alice , Grome Heather N 
Published: January 2025

Abstract

Background
Escherichia coli is the most frequent cause of urinary tract infections (UTIs) in the US, but surveillance for urinary E. coli (uEC) is often limited to multidrug-resistant strains. The CDC’s Emerging Infections Program piloted one month of active population- and laboratory-based surveillance for uEC of any phenotype in 3 U.S. sites (representing &gt;3.4 million people) to better characterize its epidemiology and burden.

Methods
We defined an incident uEC case as the first E. coli isolated from urine in a resident of the surveillance area during August 2023. Demographic data were obtained for all incident cases. Approximately 400 cases per site were randomly selected for chart review. One-month incidence rates were generated using 2022 US census data for participating surveillance areas. Cases were classified as community-associated (CA; no healthcare risk factors); hospital-onset (HO; urine obtained ≥ 3 days after hospital admission), or healthcare-associated, community onset (HACO; urine obtained in a non-hospital setting or &lt; 3 days after hospital admission with healthcare exposures in the prior year).

Results
Of 5241 uEC patients, 86.1% were female; median age was 60 years (IQR 37–76). The 1-month incidence rate was 151.7 per 100,000 population and greater among those aged ≥ 60 vs &lt; 60 years (362.7 vs 94.0).
Of 1197 patients with data from chart review, 1104 (92.2%) had cultures collected as an outpatient; 732 (61.2%) had an underlying comorbidity reported; 1113 (93.0%) had a documented UTI diagnosis; 269 (22.5%) reported recurrent UTI; and 43 (3.6%) developed E. coli bacteremia. No signs or symptoms associated with uEC were reported for 372 (31.1%) patients. In total, 287 (24%) were hospitalized within 30 days after urine culture collection; 51/287 (17.8%) had a urinary catheter in place 2 days before culture collection. Most uEC were CA (867; 72.4%), followed by HACO (325; 27.2%) and HO (3; 0.3%).
Of 3289 uEC isolates with local testing results, 255 (7.8%) were extended-spectrum β-lactamase producing and 5 (&lt; 1%) were carbapenem-resistant.

Conclusion
These findings emphasize the high burden of uEC in these communities, notably among older adults and females. Effective prevention strategies are needed to decrease uEC-associated morbidity.

Disclosures
All Authors: No reported disclosures
P-296. Risk Factors and Treatment Outcome of Multidrug-Resistant Acinetobacter baumanii Pneumonia with or without COVID-19 Infection in an Infectious Diseases Hospital from January 2020 to December 2022: A Retrospective Cohort Study
Authors: Yanes Ryan R , Edrada Edna M , Solante Rontgene 
Published: January 2025

Abstract

Background
Acinetobacter baumanii has become one of the most virulent pathogens for most hospitalized patients worldwide. Compared to the United States, Asia has a higher incidence and percentage of multidrug resistance (MDR). With the emergence of COVID-19 infection, patient's risk factors and outcomes are important to understand the correlation of the two disease entities.

Methods
Single-center, retrospective cohort study that utilized records to determine the risk factors and clinical outcome of adult patients with Multidrug-resistant Acinetobacter baumanii pneumonia admitted at San Lazaro Hospital for a 3 year period. Cox regression analysis was employed to determine predictors for mortality.

Results
A total of 70 patients were included and 9 (12.8%) of which were seen to have COVID-19. With regards to Acinetobacter baumanii resistance; 51.4% had Multidrug-resistance, 21.4% had Pandrug-resistance, and 27.1% had Extensively drug-resistance. In terms of treatment, most patients had Meropenem (31.4%) or Meropenem + other antibiotics (27.4%). The mean length of hospitalization did not differ significantly between non-COVID-19 (21.4 days) and COVID-19 patients (18.4 days) (p=0.711). Also, mortality rates did not differ significantly between non-COVID-19 (60.7%) and COVID-19 patients (55.6%) (p=0.771). Having Endotracheal tube was seen to be a significant predictor for mortality among patients with Multidrug-resistant Acinetobacter baumanii pneumonia (HR=5.0, 95%CI=1.4 to 16.4, p&lt; 0.0001). On the other hand, Meropenem use was significantly associated with improved survival whether in single (HR=0.3, 95%CI=0.08 to 0.8, p=0.025), or in combination (HR=0.2, 95%CI=0.07 to 0.8, p=0.026).

Conclusion
Among patients with Multidrug-resistant Acinetobacter baumanii pneumonia, length of hospital stays, and mortality rates did not differ significantly between those with and without COVID-19. Being on an Endotracheal tube increases the risk of mortality compared to those without invasive procedures. Meropenem with or without combination was seen to be effective in reducing the risk of mortality in this study.

Disclosures
All Authors: No reported disclosures
P-298. Treatment of Carbapenem-Resistant Gram Negative Bacteremia based on Polymixin MIC
Authors: Menon Sruthi , Lavanya S , Anthur Nair Ajay , Babu Thomas , Murali A , Nair Krishna S 
Published: January 2025

Abstract

Background
Recent studies from India have noted increasing resistance against ceftazidime- avibactam in enterobacteriacea and non-fermenters and hence, polymixins are mainstay in the treatment of carbapenem-resistant gram negative (CRGN) infections. There is no susceptible breakpoint for polymixins in view of concerns with clinical outcome and therefore, guidelines recommend combination therapy. However, studies have failed to show the superiority of polymixin combination therapy over monotherapy. Invitro data shows ≥ 90% PK-PD target attainment for isolates with colistin MIC ≤ 0.5 mg/L, but lower success rates in isolates with higher MICs. Aim of the study is to evaluate if the choice of treatment of CRGN infections can be guided by polymixin MIC.

Methods
We retrospectively evaluated critically-ill patient with CRGN bacteremia with intermediate in vitro susceptibility to colistin (MIC ≤ 2 mg/L; as per CLSI) at a tertiary care hospital in India from January 2022- June 2023. Patients who received treatment for the CRGN bacteremia for &lt;48 h were excluded. Based on polymixin MIC, patients were grouped into two study groups: those that received polymixin monotherapy and those that received polymixin in combination with another agent susceptible in vitro. Chi-square test was used for categorical data and student’s t-test for continuous data. Analysis was performed using SPSS v28 and statistical significance was defined as p &lt; 0.05.

Results
Of the 114 patients with CRGN bacteremia, 64 (56%) had an MIC of ≤ 0.5 and 50 (44%) had MIC ≥ 1. There was no statistically significant difference in the ICU mortality between monotherapy and combination therapy arms (16% vs 15%; P = 0.9778) for polymixin MIC ≤ 0.5. However, when the MIC was ≥ 1, a higher mortality was observed in the polymixin monotherapy arm (82% vs 39%; P = 0.0029).

Conclusion
Isolates with MIC ≤ 0.5 can be treated with polymixin monotherapy alone while isolates with MIC ≥ 1 require a combination therapy of polymixin with another antibiotic suseptible invitro. However, this is a single centre retrospective study and further clinical trials are required to ascertain the feasibility of polymixin MIC guided treatment of CRGN infections.

Disclosures
All Authors: No reported disclosures
P-300. Antimicrobial Resistance Focus in French ICU: A national surveillance network analysis on Pseudomonas aeruginosa nosocomial infections
Authors: Bourge Xavier , Friggeri Arnaud , Lepape Alain , Prevot Claire , Machut Anais , Vacheron Charles-Hervé 
Published: January 2025

Abstract

Background
The aim of this study was to perform a comprehensive description on a cohort of Pseudomonas aeruginosa infected patients in ICU, comparing their characteristics between susceptible and resistant strains, to understand the impact of resistance on clinical decisions and to characterize patients at risk of MDR.
Site of infection of Pseudomonas aeruginosa

Methods
Adult patients hospitalized in France for at least 48 hours in ICU participating to REA-REZO surveillance between 2018 and 2021 were included in the data base used to create this cohort.
Resistance patterns of Pseudomonas aeruginosa

Results
4196 patients with nosocomial Pseudomonas aeruginosa infections were included in this cohort. Most infections were identified in patients with pneumonia, with a consistently high prevalence ranging from 71.5% to 74.5% depending on the year.
Among the Pseudomonas, 1734 (31.0%) were resistant to piperacillin/tazobactam, 1331 (23.8%) were resistant to ceftazidime, and 1191 (21.3%) were carbapenem resistant. A statistically significant difference (p&lt; 0.001) in resistance patterns between the first and subsequent infections is seen, notably for resistance to carbapenems which rose markedly from initial to subsequent infections, from 16.3% to 27.8% (p&lt; 0.001).
Regarding occurrence of resistant Pseudomonas strains, statistically significant differences in age distribution among the resistance groups are noted (p&lt; 0.001), particularly evident in patients under 55, where 24.0% of those with dual resistance are under this age threshold, compared to 19.7% with no resistance. The SAPS II score was higher among resistant strains, as well as the duration in ICU stay, suggesting more challenging infections.
Description of the patient with Pseudomonas aeruginosa infections

Conclusion
These results reaffirm the critical challenge posed by resistant Pseudomonas in the ICU. It highlights the need for comprehensive antibiotic strategies that address the clinical, psychological, and economic dimensions of this issue.

Disclosures
Xavier Bourge, PharmD, MSD France: Employee Arnaud Friggeri, MD, MSD France: Advisor/Consultant Alain Lepape, MD, MSD France: Grant/Research Support Claire Prevot, n/a, MSD France: Employee Anais Machut, n/a, MSD France: Grant/Research Support Charles-Hervé Vacheron, MD, MSD France: Grant/Research Support
P-301. What Resistant Bacteria Are Lurking Outside Our Hospitals?
Authors: Yusuf Yasna , Awoyomi Olubosede , Wang Yongsheng , Bradbury Alison , Episcopia Briana , Abdallah Marie , Quale John 
Published: January 2025

Abstract

Background
Contamination of hospital environmental surfaces with resistant Enterobacterales and non-fermenting bacilli can facilitate nosocomial transmission. Little is known regarding the extent of contamination of environmental surfaces immediately outside the hospital setting.

Methods
Cultures of environmental surfaces surrounding hospitals in New York City were incubated at 37oC in MacConkey broth containing 4 mg/L ceftazidime and amphotericin B. Two sets of cultures were obtained: Group 1 cultures involved 42 high-touch surfaces within a two-block radius of each hospital that were cultured with rayon-tipped swabs. Group 2 cultures involved 5 surfaces of transportation centers near (n=8) and distant (n=8) from hospitals that were wiped with saline-saturated sterile gauze. Bacteria were identified using 16S ribosomal sequencing; β-lactamases were identified by PCR sequencing.

Results
In Group 1, the 336 swab cultures from surfaces around 8 hospitals yielded 66 cephalosporin-resistant bacteria, including 26 Brucella (Ochrobactrum) spp. and 12 Acinetobacter spp. One isolate of Brucella (Ochrobactrum) spp. was found to possess the carbapenemase OXA-24. Surfaces around 2 of the 8 hospitals accounted for 73% of the Brucella (Ochrobactrum) spp.
In Group 2, the 40 gauze cultures of transportation center surfaces near 8 hospitals yielded 38 bacteria. Of the 38 bacteria, 15 were Brucella (Ochrobactrum) spp. and 8 were Acinetobacter spp. In comparison, the 40 gauze cultures of 8 transportation center surfaces distant from hospitals yielded 33 isolates, including only 5 Brucella (Ochrobactrum) spp. (P=.03 compared to cultures near hospitals) and 6 Acinetobacter spp. No members of Enterobacterales were recovered in any of the Group 1 or Group 2 cultures.

Conclusion
Cephalosporin-resistant Enterobacterales were not recovered in any environmental cultures around hospitals. Both Brucella (Ochrobactrum) spp. and Acinetobacter spp. were frequently recovered; Brucella (Ochrobactrum) spp. appeared to be territorial and a reservoir for OXA-type carbapenemases.

Disclosures
All Authors: No reported disclosures
P-312. Elimination of barrier contact precautions for Vancomycin-Resistant Enterococcus (VRE)-colonized patients was not associated with the acquisition of VRE in a tertiary care center
Authors: Chanderraj Rishi , Kidder Ian , Dombecki Carey , Wasylyshyn Anastasia , Washer Laraine , Mills John , King Aaron , Woods Robert 
Published: January 2025

Abstract

Background
In April 2020, the University of Michigan discontinued barrier contact precautions for Vancomycin-Resistant Enterococcus (VRE) colonized patients while maintaining VRE surveillance. We conducted a retrospective cohort study to assess the impact of this policy change on the risk of VRE acquisition
Inclusion and Exclusion Criteria of the Cohort

Methods
We analyzed patients admitted between 1/2018 and 3/2021 who underwent weekly surveillance. The primary outcome was VRE-free survival; the main exposure was admission before or after the contact precaution policy. Demographics, Elixhauser comorbidity index, antibiotic and PPI exposure, and colonization pressure were incorporated as covariates in an extended Cox proportional hazard model of VRE-free survival. Time-varying covariates were accounted for and modeled using log-transformed time. Patients were censored at discharge or death.
VRE-free survival before and after change in contact precautions policy
Change in contact precaution policy was not associated with an increased hazard of VRE-acquisition in single variable analysis

Results
We identified 2,221 patients admitted before the policy change and 1,830 after, with 225 cases of VRE acquisition before and 196 cases after. No significant differences in age, demographics, antibiotic use, or PPI exposure were observed among VRE patients admitted before and after the policy change. However, VRE patients admitted before the policy change had more medical comorbidities (mean Elixhauser: 23.64 before, 20.77 after; p=0.008) and lower exposure to colonization pressure (mean VRE patient days: 13.4 before, 29.9 after; p=0.019).
In a multivariable extended Cox proportional hazard model, admission before or after the change in contact precaution policy showed no significant association with VRE-free survival (HR 0.81-1.1), or infection with VRE (HR 1.01, 95% CI 0.92-1.21). The most significant risk factors for VRE acquisition were vancomycin treatment (HR 1.60, 95% CI 1.25-2.03, p&lt; 0.001) and PPI treatment (HR 1.43, 95% CI 1.15-1.77, p=0.001).
Multivariable cox-regression model of risk factors for VRE acquisition
There was no association between the change in contact precautions policy and risk of VRE acquisition

Conclusion
The policy change to eliminate isolation and barrier precaution requirements for VRE patients was associated with no detectible increase in the hazard of VRE acquisition. The most significant risk factors for VRE acquisition were vancomycin and PPI treatment. Our results suggest that appropriate use of PPI and antimicrobial stewardship may have a greater impact on preventing the spread and acquisition of VRE than barrier precautions.

Disclosures
Laraine Washer, MD, Ferring Pharmaceuticals: Advisor/Consultant
P-320. National Estimates of Rates and Resistance Trends of Enterococci Cases in the United States, 2012-2022
Authors: Maillis Alex , McCarthy Natalie , Lutgring Joseph D , Reddy Sujan , Wolford Hannah , Baggs James 
Published: January 2025

Abstract

Background
Enterococci are common causes of both community-onset (CO) and hospital-onset (HO) infections; vancomycin-resistant enterococci (VRE) are a serious threat. We sought to describe national estimates of Enterococcus faecalis and E. faecium rates and the proportion of cases that were vancomycin-resistant from 2012-2022

Methods
We identified a cohort of patients from the PINC AI and BD Research Insights databases with a clinical culture yielding an E. faecalis or E. faecium isolate with accompanying antimicrobial susceptibility testing (AST). Cultures obtained from rectal, perirectal or nasal swabs were excluded. E. faecalis or faecium isolates resistant to vancomycin were considered VRE. Isolates from patients with no culture yielding the same species and vancomycin AST phenotype in the previous 14 days were counted as an incident case. CO cultures were obtained ≤ day 3 of hospitalization; HO cultures were obtained ≥ day 4. We used a raking-procedure to determine weights for extrapolating the number of discharges included in our sample to match the national distribution of discharges, stratified by bed size, U.S. census division, urban/rural designation, and teaching status, for U.S. hospitals included in the American Hospital Association survey. Weighted rates were calculated over time as cases per 10,000 hospitalizations. The proportion of VRE (%R) was calculated as the rate of VRE cases divided by the rate of all cases of that species with an AST result.

Results
There were 810 unique acute care hospitals from 2012-2022. Weighted estimates resulted in 124,570 E. faecalis and 516,724 E. faecium incident cases nationally. Rates of CO and HO E. faecalis and E. faecium declined from 2012-2018 and increased from 2018-2021 (Figures 1-4). E. faecalis %R for vancomycin remained stable over the study period (CO: 4-5%, HO: 4-6%), while E. faecium %R declined over the study period from 67% to 57% among CO cases, and from 78% to 70% among HO cases.

Conclusion
Enterococci and VRE rates have increased recently while the proportion of resistant isolates has been stable for E. faecalis and falling for E. faecium. This suggests rate increases may be due to factors affecting all enterococci (e.g., host susceptibility or pathogen factors) rather than VRE specific factors (e.g., vancomycin exposure).

Disclosures
All Authors: No reported disclosures
P-323. Evaluation of WHO Five Moments Compliance Among Nursing, Paramedical Staff, and Emergency Medicine Technicians in a Tertiary Care Hospital in India: Expected vs. Actual
Authors: Sunny Alvin , Kochuparambil Jose J 
Published: January 2025

Abstract

Background
In tertiary care hospitals of a resource limited country like India, understanding hand hygiene (HH) compliance among nursing, paramedical staff, and emergency medical technicians according to the WHO Five Moments (5M) protocol is critical for improving infection control practices and patient outcomes.

Methods
Utilizing a pre-designed structured hand hygiene audit tool, this study conducted over 300 hours of direct HH observations between 2022 and 2022 at a tertiary care hospital in India. A total of 150 nursing staff, 60 paramedics, and 20 emergency medical technicians were included in the study cohort. Compliance with WHO 5M guidelines, including hand washing (50 seconds) and alcohol rub (25 seconds), was meticulously observed and recorded. Following the initial observation period, a targeted training program on the WHO Five Moments protocol was implemented for all healthcare professionals.

Results
A notable discrepancy between expected and actual compliance with HH protocols was evident among the observed healthcare professionals. Compliance varied across the groups: Among the 150 nursing staff, compliance rates were 55%; among the 60 paramedics, compliance rates were 40%; and among the 20 emergency medical technicians, compliance rates were 35%. Despite the established duration for HH procedures, all groups demonstrated suboptimal adherence to HH guidelines. Adherence to expected compliance increased the overall time per patient encounter by 5.5-11 minutes, highlighting the need for improved HH practices. Subsequent observations conducted six months after the training revealed a significant improvement in HH compliance rates across all groups: nursing staff demonstrated an increase to 81.3% paramedics to 68.3%, EMTs to 58.5%.

Conclusion
The study emphasizes the urgent need to address the gap between expected and actual HH compliance among healthcare professionals in Indian tertiary care hospitals. Enhanced educational interventions and reinforcement of HH practices are imperative to minimize the risk of healthcare-associated infections and improve patient safety outcomes.

Disclosures
All Authors: No reported disclosures