bluuebunny/crossref_metadata_2025_split huggingface dataset:
577. Visual Recognition of GAS Pharyngitis Based on a Photographic Image: A Physician Survey
Authors: Hamdy Rana F , Berkowitz Deena , Zhang Anqing , Ansusinha Emily , Dome Jeffrey S , Shekhar Raj 
Published: November 2023

Abstract

Background
Sore throat is one of the most common reasons for an ambulatory pediatric visit in the U.S., and Group A Streptococcus (GAS) pharyngitis is diagnosed in 10-30% of children presenting with pharyngitis. While some prediction rules based on clinical signs and symptoms can reliably identify a low-risk patient, clinical signs or symptoms alone are insufficient in identifying a patient with GAS pharyngitis. The ability to identify GAS from non-GAS pharyngitis from a photographic image has not been previously determined. We conducted a survey to determine clinicians’ ability to identify a GAS vs non-GAS pharyngitis based on a photographic image presented with and without a patient’s clinical data.

Methods
We devised an online electronic survey with photographic images of the posterior pharynx of children presenting with pharyngitis without upper respiratory infection (URI) symptoms who had been evaluated for GAS pharyngitis. The survey included 20 images of the pharynx (10 positive, 10 negative for GAS) with and without clinical data. For each image, participants were asked their prediction for the patient’s GAS test result. We calculated percentage of individual responses correctly identifying GAS vs non-GAS pharyngitis.

Results
102 providers participated in the online survey (23% response rate) and 86 completed all questions in the survey. When counting each response independently, the overall percent of images correctly identified as positive or negative for GAS pharyngitis was 55.9% -- 53% without clinical data, and 59.4% with clinical data (p&lt; 0.001). Among images corresponding to patients who tested positive for GAS pharyngitis, the overall percent correct was 46.6% (38.6% without and 56% with clinical data), and among images corresponding to patients who tested negative for GAS pharyngitis, the percent correct overall was 67.3% (70.5% without and 63.4% with clinical data)(Table 1).
Table 1: Number of responses from clinician’s impression correct by those with GAS pharyngitis and vs. those without GAS pharyngitis

Conclusion
When presented with a photographic image of the pharynx of a patient presenting with pharyngitis, clinician respondents were able to identify just over half of photographic images as GAS vs non-GAS pharyngitis in children presenting with sore throat and without URI symptoms; this increased modestly when accompanied with clinical data.

Disclosures
All Authors: No reported disclosures
578. Performance of acid-fast stain, real-time PCR, and Xpert MTB/RIF in a bronchial washing for the Rapid Diagnosis of Mycobacterial infection in real-world
Authors: Hwang Joo-Hee , Hwang Jeong-Hwan , Choi Sung-Sik , Han Hyo-Jin , Lee Seung Yeob , Park Joonhong , Jo Dae Sun , Cho Yong Gon , Kim Dal Sik , Lee Jaehyeon 
Published: November 2023

Abstract

Background
Mycobacterium culture remains still the gold standard for diagnosing mycobacterium infections, but there are some limitations. Acid-fast stain and simultaneous molecular methods are recommended for early diagnosis and treatment. Bronchial washing has been reported to be an effective diagnostic sample, even in cases sputum smear tests are negative. Additionally, it can be used in multiple assays. Therefore, we analyzed the clinical performance of acid-fast stain, real-time PCR, and Xpert MTB/RIF assay compared to mycobacterial cultures in the same bronchial washing.

Methods
We screened laboratory data from January 2018 to December 2020 at Jeonbuk National University Hospital. We enrolled the samples that all the tests for analysis, acid-fast stain, rPCR, Xpert MTB/RIF, and mycobacterial culture, were ordered simultaneously. The study was approved by the Institutional Review Board of Jeonbuk National University Hospital (CUH 2022-05-036-001). In short, the bronchial washing was sent to a clinical microbiology laboratory. The cultures were done with 2% Ogawa medium and BacT/Alert MB culture bottle after NALC-NaOH. The rPCR and the Xpert MTB/RIF was done according to the manufacturer's guide. The statistical analysis was done with Excel 2016 and Analyse-it.

Results
A total of 1966 samples were enrolled, and the culture-positive sample is defined when either the solid or liquid cultures showed positive. In the mycobacterium culture, 12.8% were MTB positive, and 10.7% were non-tuberculosis Mycobacterium (NTM) positive. The sensitivity and specificity of acid-fast stain were 45.6% and 98.9%, respectively, compared to mycobacterium culture positive, including MTB or NTM. The sensitivity and specificity of rPCR in MTB and NTM are 85.7%/94.3% and 52.9%/99.3%, respectively, and Xpert MTB/RIF in MTB cases was 94.8% and 92.1% (Table 1).

Conclusion
The acid-fast stain is still a valuable diagnostic tool despite its low sensitivity because it is easy to prepare and it doesn't require specialized equipment or facilities. The rPCR for MTB showed reliable results. However, in rPCR for NTM, the sensitivity was much lower than MTB. Xpert MTB/RIF showed superior sensitivity than rPCR here. The assays should be used strategically in suspected mycobacterium infections.

Disclosures
All Authors: No reported disclosures
587. Research and Development of Image Recognition AI to Estimate Bacterial Species using Gram Stain Findings in Aerobic and Anaerobic Blood Culture Bottle
Authors: Miyatsuka Isao , Yamamoto Kei , Ohji Goh , Ohmagari Norio , Kurokawa Masami , Ebisawa Kei Furui , Ohnuma Kenichiro , Kusuki Mari , Nakada Mitsutaka , Maeta Shogo 
Published: November 2023

Abstract

Background
Background
In the highly fatal infectious disease of bacteremia, the ability to select antimicrobial agents at an earlier time is critical not only for early patient recovery, but also for reducing the development of resistant organisms. Gram staining of blood cultures is a useful test for early selection of antimicrobial agents, but it requires some skill in deciphering. Therefore, we developed an image analysis system for Gram stain images of blood cultures and have verified whether it is possible to estimate the bacterial species to facilitate the initial selection of antimicrobial agents, regardless of the level of proficiency.

Methods
Method
Slides and bacterial species-identification information from an anonymized Gram stain registry at two medical institutions, National Center for Global health and Medicine (NCGM) and Kobe University Hospital (KUH), were used for the study. 1113 cases of aerobic bottles and 1060 cases of anaerobic bottles were included. Mock-specimens were used for the rare bacteria. A total of 23,947 images were generated by capturing the observation field of view of an optical microscope with a smartphone. Table 1 shows the bacterial classification of aerobic bottles and Table 2 shows the bacterial classification of anaerobic bottles. The data were divided into training data and test data at a ratio of 8 to 2 for each category.Table 1.A total of 16 categories of bacteria were used for classification of aerobic bottlesTable 2.A total of 16 categories of bacteria were used for classification of anaerobic bottles

Results
The macro-average recall (sensitivity) and accuracy of the test data were 64% and 82% for aerobic bottles and 68% and 86% for anaerobic bottles, respectively. The results showed the possibility of classifying the performing bacterial species with an accuracy of over 70% using only Gram stained images via image recognition AI. For aerobic bottles in particular, the seven categories of GNR, GNC, GPR, GPC, yeast, No organism, and multiple bacteria are predicted to have 97% accuracy, and 90% macro average recall.

Conclusion
The research has shown that it is possible to classify bacterial species to a certain extent only by observing the Gram stain images. Our goal is to narrow down and focus more on the clinically-meaningful bacterial species, and to improve the accuracy of our classification. Also, we are planning to make comparisons with specialists in the future.

Disclosures
Kei Yamamoto, MD, Canon medical systems: Grant/Research Support|CarbGeM: Grant/Research Support|CarbGeM: 7090302|Fujirebio: Grant/Research Support|Sanyo Chemical Industries: Grant/Research Support|VisGene: Grant/Research Support Goh Ohji, MD, PhD, DTMH, CarbGeM: Advisor/Consultant
591. Positivity of Blood Culture on Automated Incubation System After 72 Hours and Clinical Significance from the Large United States Tertiary Care Center
Authors: Patel Premalkumar M , Rivera Cynthia 
Published: November 2023

Abstract

Background
Hospitals commonly use automated blood culture incubation systems that provide continuous monitoring for routine blood cultures. Detecting microorganisms early on can help optimize the utilization of antibiotics (ABx) and enable clinicians to de-escalate or discontinue ABx as necessary, making it an important aspect of antimicrobial stewardship. The BD BACTEC Fx, an automated system for blood culture incubation, holds blood culture bottles until growth is demonstrated or for five days unless an extended incubation period is requested by the infectious disease physician. We conducted a clinical evaluation of the significance of positive blood cultures after 72 hours of incubation time.

Methods
After receiving approval from the institutional review board (IRB), we obtained positive blood cultures from July 2017 to June 2020, which we then stratified based on positivity from day one to day five. To evaluate clinical significance, we retrospectively reviewed charts for positive blood culture results on day four and day five. An Infectious Diseases subspecialty team determined the clinical significance of each case.

Results
During the time frame of July 2017 to June 2020, there were 120,320 blood cultures taken. Out of these, 7,558 were determined to be positive, with 76 being positive on day 4 and 22 being positive on day 5. Upon further inspection of patients with positive blood cultures, it was discovered that repeat blood cultures continued to be positive due to either untreated sources or a high burden of bacteremia. It was also found that bottles containing fungus, particularly candida glabrata and candida albicans, tested positive on day 4 requiring treatment. Table 1 and Table 2 contain more detailed results.
Blood cultures positive on day 4
Blood cultures positive on day 4 and clinical significance
Blood cultures positive on day 5
Blood cultures positive on day 5 and clinical significance

Conclusion
In our study we have found that not all positive blood cultures at 72 hours translate into clinical scenarios requiring antibiotic therapy. In fact, prolonged antimicrobial treatment in such cases may lead to unnecessary exposure to antibiotics and increased risk of antibiotic resistance. It is important to consider the full context of clinical and laboratory findings when interpreting blood culture results, as well as any potential sources of contamination.

Disclosures
All Authors: No reported disclosures
603. Determining Effect of Media and Disk Source on Reproducibility and Relationship between Broth Microdilution and Disk Diffusion Testing of Cefiderocol
Authors: Takemura Miki , Saiki Mizue , Yamashiro Hidenori , Anan Naomi , DeJonge Boudewijn L , Slover Christine M , Longshaw Christopher M , Henriksen Anne , Yamano Yoshinori 
Published: November 2023

Abstract

Background
Cefiderocol (CFDC) is a siderophore cephalosporin with broad activity against Gram-negative bacteria. Discrepancies in susceptibility testing for CFDC have been reported. In this study susceptibility testing was performed using broth and agar medium and disks from various manufacturers to evaluate the reproducibility across the different sources and determine the relationship between MIC and inhibition zone.

Methods
12 Enterobacterales, 12 P. aeruginosa, 12 A. baumannii with in vivo efficacy results in the murine thigh infection model under humanized PK of CFDC were evaluated. MICs were determined (10 replicates per media per isolate per day) using broth microdilution with iron-depleted cation-adjusted Mueller-Hinton broth (ID-CAMHB) prepared from BD BBL, BD Difco, Oxoid and Merck. The disk zone was determined (3 replicates per media/disk per isolate per day) with CFDC disks from Hardy and Liofilchem and Mueller Hinton Agar from BBL and bioMerieux. Testing was conducted for 3 days using the same inoculum for MIC and disk diffusion studies on each day. Susceptibility was interpreted according to 2023 CLSI breakpoints.

Results
Good reproducibility of MIC was observed for the ID-CAMHB from each manufacturer for all isolates, except for 2 A. baumannii due to heavy trailing and skip. MIC variation was observed between ID-CAMHB from each manufacturer. Best categorical agreement with in vivo efficacy was observed for the MIC obtained with ID-CAMHB from BD BBL. Good reproducibility of disk inhibition zones were obtained for Enterobacterales and P. aeruginosa irrespective of the manufacturer of disks and agar medium. A. baumannii isolates with elevated MIC values frequently showed colonies in the inhibition zones, with more colonies appearing on BBL agar. This phenomenon was not reproducible, so larger variation of inner inhibition zones were observed with these isolates.

Conclusion
MIC determinations were reproducible with each ID-CAMHB medium, but variability was observed across the different ID-CAHMB; MICs obtained with BD BBL ID-CAMHB showed best correlation with in vivo data. Good categorical agreement was observed for MIC in BD BBL and BD Difco medium and disk zone, despite variable inhibition zones observed for A. baumannii.

Disclosures
Miki Takemura, n/a, Shionogi & Co., Ltd.: Stocks/Bonds Mizue Saiki, Ph.D., Shionogi & Co., Ltd.: employee Hidenori Yamashiro, Shionogi & Co., Ltd.: employee Naomi Anan, MSc, Shionogi & Co., Ltd.: employee Boudewijn L. DeJonge, PhD, Shionogi Inc.: Employee Christine M. Slover, PharmD, Shionogi,INC: Employee Christopher M. Longshaw, PhD, Shionogi BV: Employee Anne Henriksen, PhD, Shionogi: Employee Yoshinori Yamano, PhD, Shionogi HQ: Employee
606. Clinical Utility of Fungal Blood Cultures for the Diagnosis of Candidemia
Authors: Bheem Rishika , Hanisch Benjamin , Liu Benjamin M , Campos Joseph M , Ansusinha Emily , Hamdy Rana F 
Published: November 2023

Abstract

Background
Candidemia is the most common invasive fungal infection in hospitalized children, and the third most common cause of pediatric nosocomial bloodstream infections. The gold standard for diagnosis of Candida bloodstream infections is with blood cultures, and clinicians can order aerobic or fungal blood cultures when suspecting fungemia. The objective of this study is to investigate the additional utility of fungal blood cultures (in addition to aerobic blood cultures) for detecting Candida bloodstream infections.

Methods
This retrospective cohort study analyzed all patients &lt; 21 years of age, admitted to Children’s National Hospital between January 1, 2010, and December 31, 2020, and had a positive fungal blood culture (using BHI-CG plates) for Candida species on day 1 of fungemia (Table 1). Demographic data, Candida species, the concomitant positive aerobic blood cultures (using the bioMérieux BACT/ALERT blood culture system) were collected from the electronic health records through structured chart review. The time to detection of positive blood cultures was calculated for the fungal and aerobic cultures drawn on day 1 of fungemia. P-value &lt; 0.05 was considered statistically significant.Table 1:Definitions

Results
Thirty-one episodes of Candida fungemia (29 patients) were included in this study, of which 28 episodes also had an aerobic blood culture drawn on day 1 of fungemia that was positive for Candida species. All 31 episodes had an aerobic blood culture positive for Candida species within the duration of fungemia (Figure 1). The mean age of patients in the cohort was 5.7 ± 6.0 years with mean duration of admission of 67.1 days ± 79.6. C. parapsilosis was the most frequently identified Candida species (14), followed by C. albicans (10), C. lusitaniae (Clavispora lusitaniae) (2), C. tropicalis (1), C. krusei (Pichia kudriavzevii) (1) (Table 2). The mean time to positivity for aerobic blood cultures and fungal blood cultures were 26.4 ± 11.7 hours and 76.2 ± 29.6 hours, respectively (p &lt; 0.001).Figure 1:Patient Population and Analysis FlowchartTable 2:Episodes of Candida by Species

Conclusion
All episodes of Candida species that grew on fungal cultures also had at least one aerobic culture positive for Candida species within the duration of fungemia. Aerobic blood cultures had a statistically significant shorter time to positivity for Candida than fungal blood cultures.

Disclosures
Benjamin Hanisch, MD, American Society of Transplantation: Board Member|Astellas Pharma Global Development, Inc.: Support for the present publication|NIH: Site PI for International Pediatric Fungal Network- funds to institution Joseph M. Campos, PHD, Accelerate Diagnostics: Honoraria|GenMark Diagnosticd: Honoraria
610. Voriconazole versus isavuconazole in patients with invasive aspergillosis: a retrospective study in a medically insured population across the United States
Authors: Chan Sophea , Stoudenmire Laura Leigh , Zhan Duna , Chen Xianyan , Henao Martínez Andrés F , Chastain Daniel B 
Published: November 2023

Abstract

Background
Isavuconazole demonstrated similar outcomes but improved tolerability versus voriconazole (VCZ) for invasive aspergillosis (IA). Despite this, VCZ remains the treatment of choice for IA. Therefore, we compared outcomes between patients with IA treated with VCZ versus isavuconazole (ISA).

Methods
Patients with IA treated with either VCZ or ISA as monotherapy between January 1, 2017 and August 31, 2020 were identified from the IBM® MarketScan® Research Databases using ICD-10-CM diagnosis codes and national drug codes (NDC), respectively. The index date was the first fill date for either VCZ or ISA during the study period. To be included, patients were required to have continuous medical and pharmacy benefits enrollment before the index fill for either VCZ or ISA, throughout the treatment period, and for ≥ 28 days after treatment ended based on day supply. Patients with a history of liver transplant or hepatic dysfunction were excluded. Treatment completion, defined as fill history for ≥ 42 days, and adverse events, during the treatment and follow-up periods, were compared between those treated with VCZ and ISA.

Results
Of 563 patients with IA, 425 received VCZ and 138 received ISA. The mean age (51.4 ± 16.8 vs 51.9 ± 12.8 years, p=0.77) and proportion of male patients (52% vs 49%, p=0.61) were similar in both groups. The most common comorbidities among those treated with VCZ and those treated with ISA were chronic obstructive pulmonary disease (38% vs 27%, p=0.03), diabetes mellitus (22% vs 22%, p=0.98), and lymphoma (8% vs 14%, p=0.04). Similar proportions of patients in the VCZ group and ISA group had commercial insurance or Medicare (63% and 10% vs 71% and 12%, p=0.94 overall). Diagnosis of IA was evenly distributed between the inpatient and outpatient settings in each group. The rate of treatment completion was comparable between patients prescribed VCZ and those prescribed ISA (88% vs 91%, p=0.50). Adverse events were reported by 53% of patients treated with VCZ and 45% treated with ISA (p=0.11), though few patients switched therapy during the 6-week treatment period (n=4 for VCZ and n=1 for ISA).

Conclusion
VCZ was prescribed 3 times more often than ISA for IA, but rates of treatment completion and adverse events were similar between groups.

Disclosures
All Authors: No reported disclosures
617. Laboratory capacities to diagnose and treat Invasive Fungal Infections in Europe: results from an ECMM survey
Authors: Salmanton-Garcia Jon , Hoenigl Martin , Gangneux Jean-Pierre , Segal Ester , Cornely Oliver A 
Published: November 2023

Abstract

Background
Invasive fungal infections (IFI) are a major threat for patients under immunosuppression or with viral respiratory infections, like influenza or coronavirus disease 2019 (COVID-19). Access to appropriate tools is vital for early diagnosis and clinical management. The European Confederation of Medical Mycology (ECMM) survey on laboratory capacities in Europe aims to decipher the current diagnostic capacity and availability of treatments for IFIs in order to guide health professionals, patients, and policymakers.

Methods
The ECMM IFI diagnostic capacity survey is online accessible at www.clinicalsurveys.net/uc/IFI_management_capacity/. A campaign seeking for mycologist feedback was launched. The survey was disseminated to all European mycologists affiliated with the ECMM and via social media (i.e., LinkedIn or Twitter) and email. Collected variables were a) institution profile, b) perceptions on invasive fungal disease in the respective institution, c) microscopy, d) culture and fungal identification, e) serology, f) antigen detection, g) molecular tests and h) therapeutic drug monitoring.

Results
258 centers from 41 countries have participated in the survey (Figure 1). Germany (n=30), France (n=28), Italy, Spain (n=23, each) and Turkey (n=21) were the origin country of almost half of the respondents. Incidence of IFI was considered as very low or low in 46.9% of the institutions, and moderate in 38.0%. Candida spp. (95.0%) and Aspergillus spp. (89.9%) were considered the most relevant pathogens. All the institutions had access (on site or outsourced) to cultures (68.2% of which could also perform susceptibility tests in molds and yeasts, 26.4% only in yeasts, 4.7% in none and 0.8% only in molds). Regarding availability of other diagnostic tests, 84.5% could also utilize microscopy, 83.7% antigen detection tests (89.8% of which at least Aspergillus galactomannan test), 73.3% molecular tests (mainly PCR), and 62.4% to serology. At least one triazole was available for prescribing in 93.0% of the institutions, whereas at least one echinocandin in 90.3% and liposomal amphotericin B in 80.2%.

Conclusion
Europe is generally well prepared to diagnose and treat invasive fungal infections. However, some institutions miss access to certain diagnostic tools and antifungal drugs.

Disclosures
Martin Hoenigl, n/a, Astellas: Grant/Research Support|Euroimmun: Grant/Research Support|F2G: Grant/Research Support|Gilead: Grant/Research Support|Immy: Grant/Research Support|MSD: Grant/Research Support|Mundipharma: Grant/Research Support|Pfizer: Grant/Research Support|Pulmocide: Grant/Research Support|Scynexis: Grant/Research Support Oliver A. Cornely, MD PhD, DZIF: Advisor/Consultant|DZIF: Board Member|DZIF: Grant/Research Support|DZIF: Honoraria|DZIF: Stocks/Bonds