bluuebunny/crossref_metadata_2025_split huggingface dataset:
243. Temporal Trends in Appropriateness of Ambulatory Antibiotic Prescribing in South Carolina
Authors: Winders Hana R , Royer Julie , Justo Julie Ann , Bookstaver P B , Weissman Sharon , Ruegner Hannah , Al-hasan Majdi 
Published: January 2021

Abstract

Background
Previous studies have reported high levels of inappropriate ambulatory antibiotic prescribing in the United States. This population-based cohort study examines temporal trends in appropriateness of ambulatory antibiotic prescribing in South Carolina.

Methods
Aggregated pharmacy claims data for oral antibiotic prescriptions among South Carolina residents &lt; 65 years old were matched with primary diagnosis codes from medical claims within 14 days of the pharmacy claim from 2012–2017. Appropriateness of antibiotics was defined as maybe indicated or not indicated based on diagnosis codes. Chi-square tests were used to examine overall temporal trend in appropriateness and the trends across age group and gender.

Results
During the 6-year period, 3,133,379 prescriptions were identified. Overall, 25.6% of antibiotic prescriptions filled were not indicated. This decreased from 27.9% in 2012 to 22.7% in 2017 (p &lt; 0.001). The most common not indicated conditions were viral upper respiratory infections (39.1%), bronchitis (26.7%), and serous otitis (10.9%). The most common maybe indicated conditions were bacterial otitis (27.5%), acute bacterial tonsillitis (24.8%), and sinusitis (23.6%). While females filled more antibiotic prescriptions, they were less likely than males to have a not indicated condition (24.7% vs. 27.1%, p &lt; 0.001). Prescribing for not indicated conditions was more likely in adults aged 40–64 (33.7%) than those aged 18–39 (23.5%) and &lt; 18 (24.2%).

Conclusion
The observed decline in inappropriate ambulatory antibiotic prescribing from 2012 to 2017 in South Carolina represents welcomed news. Further improvements in ambulatory antibiotic stewardship efforts are needed particularly in men ≥ 40 years old with acute respiratory infections.

Disclosures
Julie Ann Justo, PharmD, MS, BCPS-AQ ID, bioMerieux (Speaker’s Bureau)TRC Healthcare (Speaker’s Bureau)
246. Antibiotic Prescribing Patterns for Residents in Assisted Living Facilities
Authors: Liao Chi-Yin , Crnich Christopher J , Ford II James 
Published: January 2021

Abstract

Background
Knowledge about antibiotic utilization in Assisted Living Facilities (ALFs) is limited. Studies have primarily focused on aggregate prescribing patterns, clinical indications for antibiotics, and the types of antibiotics prescribed. Information about individual resident prescribing patterns is limited. This project addresses the gap by using data from a convenient sample of ALFs.

Methods
Data on antibiotic prescriptions from 3 ALFs in Wisconsin were collected for a one-year period. Information included start and stop dates, clinical indication, and antibiotic prescribed. Antibiotic orders for the same resident were categorized as distinct events to capture treatment courses if 1) the days between the end date of the prior antibiotic and the initiation date of subsequent antibiotic orders were &gt; 4 days, or 2) if the identified indications for the prior and subsequent antibiotic were different. Event-level indication was further defined based on (2). Descriptive statistics were used to understand antibiotic prescribing patterns at the individual and event level.

Results
A total of 207 antibiotic events among 110 assisted-living residents were identified. The patterns of antibiotic use at the resident and treatment course levels are described in tables 1 and 2, respectively. On average, each resident was received 1.9 (range:1 to 10) antibiotic treatment courses for an average of 24.8 (range: 1 to 237) total antibiotic days. The treatment duration of each treatment course averaged 14.5 days (range: 1 to 306). About 10 % of residents had 4 or more antibiotic events and days of therapy over 56 days. 43% of residents were prescribed an antibiotic without a clinical indication and 26% of the antibiotic events were not indicated. UTI was the most common indication for antibiotic treatment (31%) and ciprofloxacin was the most commonly prescribed antibiotic (22%).

Conclusion
The current study demonstrates multiple opportunities to improve antibiotic use in ALFs, including: 1) specification of indication for the antibiotic; 2) reducing unnecessary antibiotic treatments; 3) shortening durations of treatments; and 4) reducing use of broad-spectrum antibiotics. Studies on interventions that target these areas are needed.

Disclosures
All Authors: No reported disclosures
247. Validation of the Use of Oral Vancomycin Following Positive Admission Screening Testing for C. difficile
Authors: Yeturu Preethi , Parada Jorge P , Santarossa Maressa , Labuszewski Laurie , Lopez Jenna , Arimilli Seshank , Kapadia Heli , Albarillo Fritzie S 
Published: January 2021

Abstract

Background
Clostridioides difficile can cause a severe infectious colitis and is often associated with significant morbidity and mortality. C. difficile infection (CDI) is defined as the presence of diarrhea plus a positive stool test, whereas C. difficile colonization is defined as a positive stool test in the absence of diarrhea or the presence of diarrhea attributable to causes other than CDI. Widespread use of stool polymerase chain reaction (PCR) testing, especially within the first 3 days of admission, has become common at our institution and has been associated with increased number of positive C. difficile tests results. However, C. difficile colonization rates may be 15% or higher. Oral (PO) vancomycin (vanc) is first line therapy for the treatment of CDI. We sought to evaluate the appropriateness of use of PO vanc in patients who tested positive for C. difficile via stool PCR within 3 days of admission.

Methods
We reviewed the clinical history, presence of diarrhea, risk factors for diarrhea, treatment and use of an infectious disease (ID) consultation for all patients 18 years of age or older found to test positive for C. difficile by PCR on stool assays during the first 3 days of admission from 07/01/18 to 12/31/18.

Results
A total of 228 patients met inclusion criteria. 183 (80%) received PO vanc while 45 (20%) did not. 131 (71.6%) of patients who received PO vanc had diarrhea, 39 (21.3%) did not have diarrhea, 13 (7.1%) the presence of diarrhea was unknown. 41 of 143 (28.7%) of patients without ID consults received PO vanc despite not having diarrhea, while 11 of 40 (27.5%) patients seen by ID received PO vanc despite not having diarrhea (p=0.888).

Conclusion
Most patients who tested positive for C. difficile received PO vanc had documented diarrhea, meeting the definition of CDI. However, over 1 in 5 (21.3%) of patients who received PO vanc did not have diarrhea and may have been colonized rather than have true CDI. ID consultation did not decrease the number of patients without diarrhea who received PO vanc or prevent treatment of colonized patients. This work reveals there may be an opportunity for improvement regarding management of CDI vs. C. difficile colonization which may enhance antibiotic stewardship and the appropriate use of PO vanc.

Disclosures
All Authors: No reported disclosures
248. Why so Much Vancomycin and Piperacillin/Tazobactam Usage Given Known Risks of Nephrotoxicity
Authors: Son Andrea , Murphy Nina Naeger , Wadsworth Christina , Bogorodskaya Milana , Hecker Michelle 
Published: January 2021

Abstract

Background
Despite years of published data describing the increased risk of nephrotoxicity with use of vancomycin and piperacillin/tazobactam (VPT), this combination remains one of the most utilized antibiotic combinations at our institution. There is limited data describing the appropriateness of empiric use of this broad-spectrum regimen. Our primary objective was to evaluate the appropriateness of the anti-methicillin resistant Staphylococcus aureus (MRSA), anti-pseudomonal, and anti-anaerobic spectrum of activity for patients empirically treated with this combination. Our secondary objective was to evaluate the appropriateness of diagnostic evaluation in patients started on this combination.

Methods
A retrospective cohort study was performed on a random sample of unique patients prescribed the combination of VPT from October 2019 through March 2020. Demographic and clinical data were abstracted from the electronic medical record. Based on predetermined criteria, we evaluated the appropriateness of the spectrum of activity of empiric therapy and the diagnostic evaluation.

Results
Of 100 patients evaluated, 96 patients (96%) received VPT as empiric treatment. The indications for use are shown in Table 1. Pneumonia and soft tissue/bone/joint infections were the most common indications. The appropriateness of anti-MRSA, anti-pseudomonal, and anti-anaerobic therapy is shown in Table 2. In only 35% of patients was the full spectrum of activity appropriate. Of 47 patients treated empirically for pneumonia, 35 (74%) had an order for a respiratory culture and 7 (15%) for a nasal MRSA surveillance culture. Of 30 patients treated empirically for soft tissue//joint infections, wound cultures were obtained in 22 (73%). Nineteen patients underwent surgical intervention, of whom 17 (89%) had cultures obtained.
Table 1. Indications for Empiric Vancomycin and Piperacillin/tazobactam Combination Therapy

Table 2: Appropriateness of Spectrum of Activity for Empiric Vancomycin and Piperacillin/tazobactam Combination Therapy

Conclusion
At our institution VPT use was usually empiric and unnecessarily broad for the syndrome being treated. Microbiologic testing was suboptimal and may have resulted in prolonged therapy. Although interventions aimed at de-escalating VPT are useful, interventions aimed at ensuring appropriate empiric use of this combination and ensuring appropriate diagnostic testing may be just as important.

Disclosures
All Authors: No reported disclosures
249. A metabolomic study of patients with A. baumannii bacteremia
Authors: Sun Hsin-Yun , Cheng Aristine , Chuang Yu-Chung , Wang San-Yuan , Kuo Ching-Hua , Tseng Yufeng , Chen Yee-Chun 
Published: January 2021

Abstract

Background
A. baumannii has become an emerging pathogen of healthcare-associated infection with significant mortality. The present study aimed to identify specific biomarkers to predict patient survival of A. baumannii bacteremia by metabolomics.

Methods
From July 2011 to November 2014, a total of 60 patients with A. baumannii bacteremia and available blood samples within 4 days of the onset (Day 0) of bacteremia were included for analysis. They were categorized into two groups depending on their survival at Day 14. Metabolomic profiles of the blood specimens collected at Day 0–4 of survival and death groups were compared to identify specific biomarkers to predict patient survival at Day 14. The patients were divided in the training (n=40) and validation (n=20) sets, and the logistic regression-based receiver-operation characteristic (ROC) was used to find the potential markers.

Results
The Day 14 mortality of the included patients was 20.0% (12/60). The partial least square-discriminate analysis (PLS-DA) scores plot separated the survival and death groups (Figure 1). Thirteen metabolites, L-Isoleucine, Ofloxacin, P-Hydroxybenzaldehyde, Hippurate, Indolelactic acid, Kynurenate, N-Acetyl-L-alanine, Sebacic acid, N-Acetylaspartylglutamic acid, Hematoporphyrin IX, and Urocanic acid reached the statistical significance (p &lt; 0.05) and the accuracies of training and validation sets were greater than 0.8 and 0.6, respectively (Figure 2 and Table 1). Moreover, the Wilcoxon rank sum test results of those metabolites reached the statistical significance (Table 1).
Future 1: (A) PLS-DA scores plot for death and survival groups. (B) The loading plot of PLS-DA and the distribution of the thirty important metabolites with VIP values of &gt;1.5.

Figure 2. Box plots showing significant changes of the 13 potential markers in the level of metabolites among the death and survival groups.

Table 2: Identified metabolites, p value, VIP, and the result of logistic regression.

Conclusion
Metabolomics had the potential to identify metabolites to predict survival in patients with A. baumannii bacteremia.

Disclosures
All Authors: No reported disclosures
250. Blood Stream Infections (BSI) in Pediatric Neuroblastoma High Risk: Emphasis on Viridans Group Streptococci (VGS) Bacteremia
Authors: Alali Muayad , Hageman Joseph 
Published: January 2021

Abstract

Background
Febrile neutropenia’s (FN) literature has focused on acute leukemia and undergoing allogeneic stem cell transplantation (SCT) as high risk factors for microbiological documented infection (MDI) and blood stream infection (BSI). Comprehensive studies on in pediatric Neuroblastoma high risk (NB-HR) who receive highly myelosuppressive therapy are lacking.

Methods
We conducted a retrospective medical record review of pediatric patients who received any oncology care at UCM Comer Children’s Hospitals.with a diagnosis of FN who had at least 1 blood culture obtained and one of the following underlying diagnoses (AML, lymphoblastic leukemia ALL), NB-HR, and other solid tumors (ST). SCT patients were excluded from study. We reviewed pathogens isolated from blood cultures (BCx) and determined whether they were pathogens or contaminants using IDSA guidelines. Comparative analyses of BSI rates between NB-HR and other underlying diagnoses were done.

Results
A total of 560 FN episodes (FNEs) were identified in 230 patients. FNEs occurred in NB-HR were 102 in 77 patients. Fifty-seven percent of patients developed one or more BSI or MDI during induction chemotherapy. The mean age was 11.0 (SD=6.5) years. True BSI occurred in 138 (24.6%) of FN episodes. The organisms that were most frequently isolated from were viridans group streptococci (VGS) (25%). The highest rate of BSI occurred among FNEs with AML (44/115, 37%) followed by NB-HR 26/110 (25%) Table1. Overall BSI rate in NB-HR group is higher than other solid tumors (25 vs 17%, P=0.03). In subset analysis, VGS bacteremia was highest among FNEs with AML and NB-HR compared with ALL (8.7 and 8.8 % vs 6%) P&lt; 0.04 and P=0.02 respectively.
Notably, the gram positive/ gram negative (GP/GN ratio) in NB-HR compared with ST was significantly higher (OR =2.26, CI 95% 1.5–7.8, P&lt; 0.01), this was likely due to a higher VGS rate (8.8% vs 2%, OR=4.2, P &lt; 0.01). Rate of GN-BSI are same in each of ALL,HR-NB and ST.

Conclusion
Our large Neuroblastoma cohort showed that NB-HR during induction chemotherapy are higher risk for VGS bacteremia, compared with other solid tumors. Further prospective studies are needed to investigate infection related complication in this high risk group and possible improved morbidity and mortality.

Disclosures
All Authors: No reported disclosures
251. High prevalence of the cefazolin inoculum effect in methicillin-susceptible Staphylococcus aureus causing bloodstream infections in a hospital network in Houston, TX
Authors: Pinargote-Cornejo Paulette M , Gomez-Villegas Sara I , De la Hoz Alejandro , Miller William R , Pedroza Claudia , Arias Cesar A 
Published: January 2021

Abstract

Background
Anti-staphylococcal β-lactams, such as anti-staphylococcal penicillins (AsPen) or cefazolin are the drugs of choice for methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infections. However, cefazolin has seen increasing use due to its better tolerance, lower cost, ease of administration and possibly better outcomes when compared to AsPen. Nevertheless, its efficacy may be compromised by the cefazolin inoculum effect (CzIE), defined as an increase in the minimum inhibitory concentration (MIC) of cefazolin to ≥16mg/L when a high inoculum (5x107 CFU/ml) is present. Previous studies have suggested that the prevalence of the CzIE varies geographically, with high prevalence in some Latin American countries. Prospective data evaluating the presence of the CzIE in deep-seated MSSA infections across the United States are lacking.

Methods
We performed a prospective observational study of MSSA bacteremia in a network of 13 hospitals in Houston, TX. Patients ≥ 18 years old, with a positive blood culture with MSSA, with at least one follow-up blood culture confirming clearance of the bacteremia, who received cefazolin or nafcillin as definitive therapy (72 hours or longer after culture results known) and whose original isolate was available for evaluation of the CzIE, were included. Patients with polymicrobial BSI, or those who received another antibiotic with activity against MSSA in the definitive therapy period were excluded. Cefazolin MICs were determined by broth microdilution at standard and high inoculum.

Results
We report the results of 50 patients enrolled from February 15, 2020-April 30, 2020. The baseline characteristics of each group are outlined in Table 1. A total of 37/50 (74%) received cefazolin as definitive therapy, and complicated bacteremia was seen in 27/50 (54%). A total of 16/50 (32%) of the MSSA isolates exhibited the CzIE. Two patients in our cohort died: both of whose isolates exhibited the CzIE and received cefazolin as definitive therapy.

Conclusion
We report a high prevalence of the CzIE in MSSA BSIs in a major US urban hospital network. Further evaluation of the clinical implications of the CzIE is urgently needed.

Disclosures
William R. Miller, MD, Entasis Therapeutics (Scientific Research Study Investigator)Merck (Grant/Research Support)Shionogi (Advisor or Review Panel member) Cesar A. Arias, MD, MSc, PhD, FIDSA, Entasis Therapeutics (Scientific Research Study Investigator) MeMed (Scientific Research Study Investigator) Merck (Grant/Research Support)
252. Increased incidence rates of positive blood cultures shortly after chemotherapy treatment initiation among individuals treated for solid malignant tumours
Authors: Roen Ashley O , Terrones-Campos Cynthia , Mocroft Amanda , Andersen Michael Asger , Helleberg Marie , Niemann Carsten Utoft , Daugaard Gedske , Specht Lena , Reekie Joanne , Lundgren Jens 
Published: January 2021

Abstract

Background
Cancer treatments suppress immune function and are associated with increased risk of infections, but the overall burden of serious infectious diseases in treated patients has not been clearly elucidated.

Methods
All patients treated for solid malignant tumours with curative intent radiotherapy (RT) and/or standard first line chemotherapy (C) at the Department of Oncology at Rigshospitalet between 01/1/2010 to 31/12/2016 were included. Patients were followed from treatment initiation to new cancer treatment, end of follow up or death whichever came first. We calculated incidence rates (IR) of positive blood culture (PBC) per 1000 person years follow up using Kaplan-Meier methods, and examined the proportion who died within 30 days of PBC.

Results
13,275 individuals were included, 4,372 (33%), 6,349 (48%), and 2,554 (19%) treated with RT, C, or concomitant RT&C, respectively, contributing 21,493 person years follow-up. 6,930 (52%) were female, the median (IQR) age was 63 (53, 70), and the most common cancer diagnoses were breast (n = 2,593 [19%]), colorectal (n=1,422 [11%]), and stomach (n=1,246 [9%]).
Overall, 564 individuals (4%) experienced 746 unique episodes of PBC, 188, 408, and 150 events in 143, 311 and 110 individuals treated with RT, C, and RT&C, of which 49 (26%), 104 (25%), 38 (25%) died within 30 days of PBC, respectively. IR of PBC significantly varied by treatment: 13.0 (95% confidence interval 11.1, 15.4), 43.9 (39.3, 49.0) and 32.0 (26.5, 38.5) per 1000 person-years follow up in the RT, C and RT&C groups, respectively (IR ratio = 3.36 (2.75, 4.10) and 2.45 (1.91, 3.14) for C and RT&C compared to RT, respectively) and time since treatment (figure). Escherichia coli (n=185, 25%), Staphylococcus aureus (n=102, 14%), Klebsiella pneumoniae (n=76, 10%), Enterococcus faecium (n=48, 6%), and Enterococcus faecalis (n= 37, 5%) were the top 5 microorganisms identified and did not vary by treatment category, p = 0.11, there were 31 (4%) cases of Candida.
Incidence rate of positive blood culture (PBC) by time since treatment initiation (0–3 months, 0–6 months and &gt;6 months) and the proportion who died within 30 days of PBC by treatment type among individuals treated for solid malignant tumours with radiotherapy [RT], chemotherapy [C] and concomitant RT&C at Department of Oncology at Rigshospitalet, University of Copenhagen between 01/1//2010 to 31/12/2016.

Conclusion
PBCs are seen more often within 3 – 6 months after C than after RT alone. PBCs are not common, but when they occur, mortality is high. More precise risk factors for PBC and prophylactic means and empiric treatments in selected high-risk patients should be investigated.

Disclosures
All Authors: No reported disclosures
253. Is Echocardiogram always indicated in Bacteremia?
Authors: Grinberg Sagy , Nagarakanti Sandhya , Ma’ayah Audai Ibrahim , Tchao Yee , Bishburg Eliahu 
Published: January 2021

Abstract

Background
Echocardiography (ECHO) is a commonly used test; and is part of the Duke’s criteria for diagnosing endocarditis (IE). Our objectives were to analyze utilization and results of ECHO in pts with bacteremia growing organisms not typically associated with IE, and to evaluate whether ECHO contributed to a diagnosis of IE.

Methods
A retrospective review in a 680-bed tertiary care hospital from 2013–2019. Adult pts with bacteremia with at least 2 positive blood cultures for an organism not typically associated with IE such as Streptococcus viridans, Staphylococcus spp. and enterococcus, and who underwent ECHO were included. Data was collected on demographics, blood cultures, timing of ECHO and its’ findings. Modified Duke’s criteria was used to diagnose IE.

Results
Ninety four pts were included. Mean age 62 yrs. (range 23-91yrs). 50 (53%) were men. DM noted in 49(52%), CAD in 37(39%), CHF in 54 (57%), chronic kidney disease in 22(23%), hemodialysis in 19(20%), history of IE in 9 (10%). Transthoracic ECHO in 34 (36%), transesophageal ECHO in 28(30%), 32(34%) had both. Identifiable sources of bacteremia were urinary tract infection in 9 (10%), pneumonia 5 (5%), PICC line 5 (5%), wound/tissue infection 3 (3%).Clinicians did not specify the indication for ECHO in any of the cases. Unidentified source of bacteremia noted in 72(77%). Bacteremia was community acquired in 70(74%). Mean days of positive blood cultures 5.6 days (range 1–34 days). Gram (-) organism isolated in 44(47%), Gram (+) in 50(53%), of these, 50 (54%) had an implanted devices/indwelling catheter: 39 cardiac implantable device, 12 indwelling/tunneled catheter. The overall yield of ECHO in bacteremia was 11/94 (12%). ECHO in Gram (-) bacteremia had yield of 9% (4/44 pts) of them only 1 met possible IE by Duke’s criteria. Gram (+) bacteremia had an ECHO yield of 14% (7/50pts); of them 4 met possible IE Duke’s criteria. None of the cases met definite criteria for IE.

Conclusion
Yield of ECHO for the diagnosis of IE in pts with bacteremia with organisms other than Streptococcus viridans, staphylococci or enterococci was low even in the presence of implanted devices or indwelling catheters. Better criteria for ECHO utilization will reduce its use and potentially increase its yield.

Disclosures
All Authors: No reported disclosures