bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-1525. Real-World Efficacy of Fosfomycin for Treatment of Cystitis Caused by E. coli Versus Non-E. coli Gram Negatives With High Rates of FosA
Authors: McCormick Ryan C , Randazza Olivia , DeWitt Michael E , Banoub Mary , Taylor Alex D , Luther Vera P , Cook Julia Christine , Williamson John C 
Published: January 2025

Abstract

Background
Fosfomycin is an appealing cystitis treatment; however, guidelines recommend against fosfomycin for non-E. coli gram negatives due to reduced in vitro activity associated with FosA, an enzyme that hydrolyzes fosfomycin but does not always result in full resistance. These concerns have yet to be corroborated in efficacy studies. The purpose of this study was to determine if fosfomycin is an acceptable treatment for cystitis caused by non-E. coli gram negatives with high rates of FosA.

Methods
This was a single-center, retrospective, cohort study evaluating the efficacy of fosfomycin for cystitis caused by E. coli versus non-E. coli gram negatives with high rates of FosA, including K. pneumoniae, P. aeruginosa, K. aerogenes, K. oxytoca, M. morganii, and E. cloacae. Patients with an inpatient or outpatient fosfomycin order to treat cystitis caused by these bacteria were included. Patients were excluded if there was a lack of cystitis symptoms, evidence of pyelonephritis, polymicrobial culture, or ≥ 48 hours of antimicrobial therapy prior to fosfomycin. The primary outcome was 30-day treatment failure defined as persistence or recurrence of cystitis symptoms with either a positive culture (same bacteria) or antibiotic re-treatment.

Results
104 cases of cystitis were included in the study, 53 in the E. coli group and 51 in the non-E. coli group. Patient characteristics are presented in Table 1. The E. coli group had a higher median BMI; 26 (49%) vs 13 (25%) were obese (p=0.013). With 32 (63%) cases, K. pneumoniae was the most common non-E.coli and all but 10 cases were Enterobacterales. Treatment failure occurred in 17 (32%) of the E. coli group and 18 (35%) of the non-E. coli group (p=0.73) (Table 2). Among the failures, about half had a repeat positive culture, all failures received re-treatment, and median time to failure was 10 days for E. coli vs 7 days for non-E. coli. Figure 1 shows time to failure within groups, and Figure 2 shows failures by species.

Conclusion
These data suggest failure rates for fosfomycin are relatively high in all cases of gram negative cystitis, regardless of FosA. Presence of FosA may not be as clinically relevant as guidelines suggest when deciding to use fosfomycin for cystitis. Additional studies are needed to validate these findings.

Disclosures
John C. Williamson, PharmD, Armata Pharmaceuticals: Grant/Research Support|Blue Collar Vaccines and Therapeutics: Board Member|Blue Collar Vaccines and Therapeutics: Ownership Interest|Paratek Pharmaceuticals: Grant/Research Support|ST Pharm Co, Ltd: Grant/Research Support
P-1548. Risk Factors for Escherichia Coli Resistance to First-line Antibiotics in Urinary Isolations in Children
Authors: Guglielmo María Cecilia , Guedes Veronica 
Published: January 2025

Abstract

Background
There is concern about the increase in antibiotic resistance to Sulfamethoxazole/trimethoprim (SMX/TMP) in urinary tract infections (UTI) in children. There is limited evidence on whether there are associated risk factors for this resistance. The Objective of our investigation is to evaluate if there is an association between E. Coli resistance to (SMX/TMP) and previous episodes of UTI, prophylaxis or antibiotic treatment, hospitalizations, urinary tract disorders, age and sex.
Characteristics of children with SMZ-TMP-resistant E. Coli isolates compared to the control group

Methods
retrospective study that evaluated 117 medical records from Nephrology service of Elizalde Hospital, in Buenos Aires , Argentina from 1/1/2018 to 12/31/2018. The sample was divided into two groups. A control group (68 patients) with E. coli sensitive to SMX/TMP in urine isolations and a group of cases (49 patients) with resistant isolates. Risk factors were considered and association was evaluated by Chi test, OR calculation
with 95% confidence intervals. Binary logistic regression was performed . Significance 0.05. Age was dichotomized into older and younger than 2 years old

Results
Sex showed no association with resistant insulation. Patients older than 2 years old, were associated with resistant isolates (p = 0.01). Patients with hospitalizations were 3 times more likely to have a resistant insulation (p = 0.001). Alterations in the urinary tract increased 3.9 times the risk of resistant isolates (p &lt; 0.0001). Greater resistance was observed in those with recurrence of infection (p &lt; 0.0001). The multivariate analysis indicated that those patients with prophylaxis had an 83 times greater risk of presenting isolates resistant to SMX/TMP than patients without this risk factor (OR 83.47, 95% CI 12.6 – 552.21)

Conclusion
Prolonged use of antibiotics and receiving antibiotic prophylaxis were the only
factors independently associated with the finding of SMX/TMP-resistant E. Coli

Disclosures
All Authors: No reported disclosures
P-1561. Use of BacterioScan 216Dx to Reduce Antibiotic Use for Suspected Urinary Tract Infection in the Emergency Department
Authors: Gao Kelly , Kumar Vishak H , Divinagracia Giovanni , Kaye Keith S , Azim Ahmed Abdul , Kirn Thomas , Berla Bert M 
Published: January 2025

Abstract

Background
Urinary tract infections (UTI) are often empirically treated in the emergency department (ED) before urine culture (UCx) results are available. 20-40% of suspected UTIs yield negative UCx and therefore are, by definition, not UTIs. BacterioScan 216Dx is an FDA cleared device that allows for point of care analysis of urine samples for bacteria in 3 hours as opposed to UCx which can take up to 48 hours. The BacterioScan system uses the trend of optical density of a urine sample mixed with bacterial growth media to identify UTI positive samples containing ≥50,000 colony forming units (CFU)/mL of a uropathogen. We describe the potential impact of a negative BacterioScan test result on antibiotic use prior to UCx results becoming available.
Table
Urinalysis Positive, BacterioScan Negative, and Urine Culture Negative Patients Treated for Urinary Tract Infection: Antibiotics Used and Duration

Methods
We performed a retrospective review of ED patients from 12/1/2023 to 4/8/2024 with a positive UA (WBC &gt;5 cells/hpf or leukocyte esterase or nitrite +) that reflexed to culture. Concurrently, the samples were tested using BacterioScan, but results were not released to treating clinicians. BacterioScan and UCx results were recorded along with patient demographics, antibiotics received, and duration of treatment. This analysis focused on UA positive, BacterioScan negative patients.

Results
600 patients had a positive UA that reflexed to culture. BacterioScan was negative in 100 of these patients. These patients had a mean age of 47.67 (SD 20.67). 66% were female. 36% identified as White, 16% African American, 4% Asian, and 44% other/prefer not to respond. 33% identified as Hispanic.
83 of 100 patients were Bacterioscan and UCx negative. Of these 83 patients, 8 (9.64%) were treated with median antibiotic duration of 5.5 days (Table).
17 patients had Bacterioscan negative/UCx positive results.13 of 17 had a mix of different bacterial species with CFUs ranging from &lt; 10,000 to 50,000. 4 UCx were positive for potential pathogens- Streptococcus agalactiae (2), Proteus mirabilis, and Klebsiella pneumoniae. Of these 4, 3 had &lt; 50,000 CFU and 1 had ≥100,000 CFU.

Conclusion
Appoximately 10% of patients of patients with UA positive/BacterioScan negative/UCx negative results could have avoided antibiotic treatment if BacterioScan results had been available to clinicians in real time. In urgent care settings, BacterioScan can help reduce unnecessary antibiotic use.

Disclosures
Keith S. Kaye, MD, MPH, Allecra: Advisor/Consultant|CARB-X: Advisor/Consultant|GSK: Advisor/Consultant|Merck: Advisor/Consultant|Shionogi: Advisor/Consultant|Spero: Advisor/Consultant Thomas Kirn, MD PhD, Selux Diagnostics: Advisor/Consultant|Selux Diagnostics: Honoraria Bert M. Berla, PhD, Bacterioscan, Inc.: Ownership Interest|Bacterioscan, Inc.: Stocks/Bonds (Private Company)
P-1579. Prediction of Prognosis of Visceral and Subcutaneous Fat Areas in Pyelonephritis
Authors: Kitazawa Takatoshi , Nakayama Shin , Wakabayashi Yoshitaka 
Published: January 2025

Abstract

Background
Visceral fat accumulation has been regarded as a poor prognostic factor for coronary artery disease. Moderate overweight and mild obesity are associated with a lower mortality in patients with several infectious diseases on intensive care units, and this phenomenon is referred to as the obesity paradox. Pyelonephritis is one of the common infectious diseases, and although computed tomography (CT) imaging is frequently used in its localization, its prognostic value is limited. In this study, we analyze the relationship between the visceral and subcutaneous fat areas in CT scans and prognosis of patients with pyelonephritis.Fig. 1ROC curves using subcutaneous and visceral fat area to discriminating surviving pyelonephritis patients from deceased pyelonephritis patientsThe black line shows the curve using subcutaneous fat area and the gray line shows the curve using visceral fat area.

Methods
We included hospitalized patients with pyelonephritis who underwent computed tomography of the abdomen. Clinical data were obtained from the medical records. Subcutaneous and visceral fat aeras were analyzed at the umbilical level using the abdominal analysis (2D) function of the 3D image analysis system volume analyzer.

Results
505 patients were included in the study. There were 497 survivors and 8 non-survivors, with both subcutaneous and visceral fat areas being lower in the non-survivors than in the survivors (subcutaneous fat area 49.3 ± 73.9 cm2 vs 123.7 ± 85.3 cm2, p=0.012; visceral fat area 42.2 ± 29.2 cm2 vs 98.4 ± 69.1 cm2, p&lt; 0.01, respectively. ROC analysis using subcutaneous and visceral fat areas to discriminate survival and death showed that the areas under the curve of subcutaneous and visceral fat areas were 0.794 (p=0.002) and 0.770 (p&lt; 0.001), respectively (Fig.1).

Conclusion
Patients with poor prognosis of pyelonephritis tended to have lower subcutaneous and visceral fat area at onset than patients with improved prognosis. The results suggest that both subcutaneous and visceral fat area using CT may have prognostic value for pyelonephritis.

Disclosures
All Authors: No reported disclosures
P-1612. Does the Use of Diagnostic Testing Vary by Race and Social Vulnerability for those Seen in the Emergency Department or Admitted to the Hospital? A Retrospective Analysis in a Large Healthcare System
Authors: Mupanomunda Maria , Cosimi Reese , Garrett-Ray Stacy D , Daragjati Florian , Ghosh Subhangi , Masoudi Frederick , Bollinger Allison , Aloia Thomas , Fogel Richard , Fakih Mohamad G 
Published: January 2025

Abstract

Background
Diagnostic stewardship complements antimicrobial stewardship by promoting appropriate use of diagnostic tools. While disparities have been reported in antibiotic prescribing and hospital-acquired infections, data are limited on diagnostic test utilization. We evaluated the association of race and social vulnerability index (SVI) on ordering of diagnostic testing in a large diverse health system.Table 1:Diagnostic Test Utilization by Race and SVI Inpatient and Observation encounters

Methods
Retrospective analysis of tests ordered for all Inpatient and Emergency Department (ED) encounters of 85 hospitals in a large health system between January 1, 2023 to December 31, 2023. The primary clinical outcome was diagnostic test utilization defined as the number of tests ordered per 100 encounters for the following: blood cultures, urinalysis (UA), urine cultures, Clostridioides difficile (C. diff), complete blood count (CBC), comprehensive and basic metabolic panels (CMP/BMP), and COVID-Influenza-RSV panel. Data were stratified across patient race and SVI.

Results
A total of 751,638 Inpatient (70% White, 18% Black/African American (AA)) and 2,440,769 ED (60% White, 27% Black/AA) encounters were included in the analysis. Inpatient White patients had higher rates of diagnostic testing for C. diff than Black/AA patients (relative difference, 16%; p&lt; 0.001) while UA, CBC, CMP/BMP, blood culture, and COVID-Influenza-RSV panel ordering was lower in White patients (relative difference, -6, -5, -5, -38; p&lt; 0.001, respectively). In the ED, test ordering was higher in White patients in all test panels except for COVID Flu RSV. Similar differences seen by race were observed by SVI, with Low/Medium-Low SVI mirroring testing in White patients and High/Medium-High SVI mirroring testing in Black/AA patients.

Conclusion
Differences were identified in diagnostic test utilization by race and SVI in the inpatient and ED settings. Additional factors such as age, diagnosis, and regional variability may need to be further examined in future analyses. Although these disparities were observed, our internal mortality data shows no differences by race. Further investigation is warranted to determine appropriateness of diagnostic test ordering in each population to better interpret the disparities identified in this study.

Disclosures
All Authors: No reported disclosures
P-1644. Antimicrobial Stewardship Opportunities for Urine Cultures Resulting After Patient Discharge
Authors: Harris Natalie , Shroba Jenny , Burrows Joshua , Deri Connor R , Erkanli Alaattin , Funaro Jason , Lee Hui-Jie , Moehring Rebekah W , Yarrington Michael E , Wrenn Rebekah 
Published: January 2025

Abstract

Background
Urinary tract infections (UTIs) constitute 3 million emergency department visits (ED) annually and 15% of outpatient antibiotic prescriptions. The outpatient setting is the highest volume of antimicrobial prescribing in the United States, however, is generally a neglected practice area for antimicrobial stewardship (AS) programs. This study sought to evaluate need for AS with an existing ED feedback system for ambulatory patients.
Primary Outcome

Methods
This multi-center, retrospective study included adults &gt; 18 years old and admitted inpatient or visited the emergency department from August 1, 2022 to February 1, 2023. Patients were included if prescribed antibiotics at discharge or within 72 hours of discharge and had a significant update to urine culture results post discharge up to 14 days. Patients were excluded if prescribed non-urinary indication antibiotic, deceased prior to final culture result, or discharged to hospice. A random 10% convenience sample was analyzed. Descriptive statistics were used to summarize patient characteristics and primary and secondary objectives.
Secondary Outcomes

Results
From a cohort of 1,362 patients, 137 encounters were screened and 111 met the inclusion criteria. Over 70% of encounters had at least one AS opportunity. Misdiagnosis attributed to 42% of all opportunities for intervention. Additionally, 20 (18%) patients received longer duration of antibiotics than indicated, and upon culture review, 14 (12.6%) patients received antibiotics post-discharge despite initial diagnosis of asymptomatic bacteriuria.

Conclusion
The majority of patients prescribed antibiotics with pending urine culture data receive unnecessary exposure in our system. Given the high frequency of misdiagnosis of UTI’s and errors in antibiotic prescribing found in this cohort, it is ripe for AS intervention and is uniquely structured with existing culture review systems as present in many EDs. Provision of decision support and provider education to reduce risks of unnecessary antibiotic therapy is needed.

Disclosures
Rebekah W. Moehring, MD, MPH, FIDSA, FSHEA, UpToDate, Inc.: Author Royalties
P-1654. Factors affecting vancomycin and piperacillin/tazobactam-induced nephrotoxicity
Authors: Munshi Ruhul , VanNatta Mollie , Khan Muhammad Haris , Alam Mohammad , Malek Alexandre E 
Published: January 2025

Abstract

Background
The concomitant use of vancomycin (Vanc) and piperacillin-tazobactam (Pip/Tazo) is one of the most common combinations utilized in infectious disease field. But, studies have hinted at an increased risk of nephrotoxicity. However, the specific factors leading to the development of acute kidney injury (AKI) remain uncertain. In this study, we sought to elucidate the potential factors contributing to AKI in pts who received both Vanc and Pip/Tazo

Methods
We performed a retrospective study of adult pts admitted at the Ochsner LSU Health Shreveport - Academic Medical Center between May 2019 and March 2023 who received at least 48h of Vanc and Pip/Tazo combination. Exclusion criteria and number of eligible pts are outlined in the flow chart. Demographics, calculation of Vanc levels and AUCs, and information on the treated infectious syndromes were all collected. AKI was defined according to RIFLE and AKIN criteria. We then compared pts who developed AKI versus those who did not.

Results
Of 1153 pts, we included 350 pts who met the inclusion criteria. Pts were divided into AKI group (n=89, 25.4%) and non-AKI group (n=261, 74.6%). Pts’ demographics at baseline were comparable between the two groups, except obesity was more prevalent in pts in the AKI vs non-AKI groups, with mean BMI of 31.52 vs 27.35, respectively, p=value &lt; 0.001 (Table 1). There were no statistically significant differences between the two groups in terms of concomitant use of potentially nephrotoxic agents, except the use of IV contrast was significantly higher in the AKI group (31.5%) compared to the non-AKI group (18.0%) with p=0.008 (Table 2). On the univariate analysis, the mean duration of combination therapy was higher in the AKI group vs non-AKI group, 4.65 vs 4.04, respectively, p=0.01. Vanc loading and maintenance doses, AUCs, and trough levels were significantly higher in the AKI group (Table 3). However, logistic regression analysis showed that IV contrast was an independent risk factor for AKI (OR=2.4, 95% CI=1.14-5.03, p=0.02).

Conclusion
Our data demonstrated that IV contrast is significantly associated with an increased risk of nephrotoxicity in pts receiving Vanc and Pip/Tazo combination therapy. The data support that the combination of vanc and Pip/Tazo is not as nephrotoxic as initially thought.

Disclosures
All Authors: No reported disclosures
P-1657. Antibiotics in hospice and the patients who receive them
Authors: Crowley Patrick , Whelan Francis , Siegel Leslie , Challener Douglas 
Published: January 2025

Abstract

Background
At the time of hospice enrollment, patients are asked whether they would potentially want antibiotics. This is little information regarding which patients are more likely to receive these antibiotics or the impact on comfort or longevity. To help guide discussions with patients and families and target future stewardship interventions, we sought to characterize the use of antibiotics in the outpatient hospice setting.

Methods
We performed a retrospective review of patients enrolled in hospice with the Mayo Clinic Health System -Midwest from 1/1/2017 through 1/1/2023. For those with documented Hospice Qualifying Condition (HQC), we assessed age at enrollment, gender, survival time (ST), and Charleston Comorbidity Index (CCI). We documented which antibiotics were prescribed and compared the rate of prescription based on the above characteristics.

Results
We identified 6452 patients with identifiable HQC. Of these, 1281 patients (19.8%) received 4173 antibiotic prescriptions. After removing refilled prescriptions, there were 2037 new prescriptions. Cephalosporins were the most common class of antibiotics prescribed (24.4% of antibiotics prescribed), followed by fluoroquinolones (19.9%), penicillin derivatives (14.4%), and trimethoprim (10.4%) (fig 1). Pulmonary (28.6%) and GI (31.9%) HQCs were most likely to receive antibiotics, neurologic was least likely (fig 2). There was no difference of age for those receiving antibiotics (80.6 yr) vs those not receiving (80.3 yr [p=0.53]), or for gender (male vs female OR 0.97 [0.86-1.10). CCI was higher in those patients who received antibiotics (4.3) than those not receiving (3.93, p&lt; 0.001). Patients were more likely to receive antibiotics the longer they survived on hospice (4.7% surviving &lt; 7d, 47.7% surviving &gt;6mo – fig 3).

Conclusion
Antibiotics are an important pharmaceutical tool in the hospice setting. Nearly 20% of patients in hospice will receive antibiotics during their hospice course, with higher chance in those surviving longer periods and those enrolled for GI or pulmonary reasons. Discussions of antibiotic are crucial for these groups, and antimicrobial steward efforts should consider focusing on these patients.

Disclosures
All Authors: No reported disclosures
P-1680. Retrospective Review of Adherence to Institutional Pneumonia Antimicrobial Guidelines at Hospital Admission
Authors: Burnette Bailey , Thompson Jesse M , Reece Becky , Burnette Jordan R , Howard Catessa A 
Published: January 2025

Abstract

Background
Literature supports the importance for institutions to have antimicrobial guidance accessible for providers in order to improve patient outcomes and antimicrobial stewardship (AMS). However, guideline adherence when prescribing for community acquired infections tends to be poor and includes more broad-spectrum antibiotics than required. We performed a review to assess adherence to our institutional pneumonia guidelines.

Methods
A retrospective chart review was conducted on all adult patients admitted to a Medicine or Hospitalist team at WVU Hospitals with an admission diagnosis of community acquired pneumonia (CAP)/pneumonia between January – June 2023. Demographic and clinical characteristics were collected as well as outcomes of interest: empiric antimicrobials and adherence to our institutional pneumonia guidelines. Data was collected and analyzed via WVU REDCap.

Results
We identified 154 patients with admission diagnosis of CAP to internal medicine services; however, 37 were excluded, as they were transfers from the ICU or outside facilities. Demographics showed 49.4% of the patients were female and median age was 69 years. 30% received antibiotics in preceding 90 days, with 77% of these for prior pneumonia. Identified comorbidities included: COPD (51.5%), Type II Diabetes (31.7%), CHF (43.6%), active malignancy (23.8%) and immunosuppressed (35.6%) (Figure 1). The median Patient Severity Index score was 91 (26-277). Adherence to institutional guidelines was 59% and of those non-adherent, 81% were over treated (Figure 2). Frequency of appropriate antibiotic use included: 24.8% ampicillin/sulbactam, 52.1% doxycycline, 33.3% ceftriaxone, and 12.8% azithromycin. Most common inappropriate antibiotic use included cefepime 28.2% and vancomycin 23.9%.

Conclusion
At 59% adherence to our pneumonia guidelines, this data shows there is a need for education and increased accessibility to institutional guidelines. Our QI intervention will include educational sessions on AMS guidelines and our CAP order panel, how to access the guidelines (via AMS app or webpage) and placement of guideline links within antibiotic orders. This study will also serve as a basis for assessing empiric treatment of other common infections and adherence to institutional AMS guidelines.

Disclosures
All Authors: No reported disclosures