bluuebunny/crossref_metadata_2025_split huggingface dataset:
194. Rapid diagnostic testing to improve management of suspected chlamydia and gonorrhea in adolescents in a Pediatric Emergency Department
Authors: Frost Holly M , Wilson Michael L , Roosevelt Genie D 
Published: December 2022

Abstract

Background
Standard turnaround times for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) testing result in unnecessary antibiotic use for patients without infection and undertreatment of patients with infection(s). We aimed to determine the impact of rapid CT/GC testing on reducing unnecessary antibiotic use, undertreatment of CT and/or GC, and length of stay in an urban safety-net pediatric emergency department (PED).

Methods
Before 2020, testing for CT/GC was performed using a batched nucleic acid amplification test (NAAT; Hologic Aptima Combo2) with results available the following day. Starting January 2020, the GeneXpert rapid NAAT (Cepheid Xpert CT/NG) with turnaround time between 90-120 minutes was available. Our primary outcome variables were under- and over-treatment. Undertreatment was defined as GC and/or CT positive patients who did not receive appropriate antibiotic treatment in the PED. Overtreatment was defined as GC or CT negative patients who received antibiotic treatment in the PED. Under- and over-treatment percentages were plotted on Statistical Process Control p charts. The balancing measure was length of stay (LOS).

Results
There were 739 patients evaluated in the baseline period (2019), 631 in the intervention period (2020) and 626 in the post-intervention period (2021). There were no differences in gender, race, ethnicity, and insurance across the 3 time periods. After introduction of the GeneXpert, over-treatment decreased from 18.4% to 8.1% (Figure). Under-treatment did not differ. Median turnaround for the GeneXpert was 119 minutes. Median LOS in minutes increased from 165 minutes (baseline) to 182 minutes (intervention) and 202 minutes (post-intervention; p&lt; .001).
Percentage of patients over-treated for chlamydia and gonorrhea.

Conclusion
Rapid CT/GC testing substantially reduced unnecessary antibiotic use but increased LOS. Given the rapid increases in CT/GC rates and antimicrobial resistance health systems should consider implementation of rapid testing to appropriately direct antimicrobials to patients most likely to benefit. A more rapid test would likely increase appropriate antibiotic use and limit impact on LOS.

Disclosures
All Authors: No reported disclosures.
195. Reducing Time to Optimal Antimicrobial Therapy (OAT) for Bloodstream Infections (BSI) due to Gram Positive Cocci (GPC) in Chains Using Rapid Diagnostics Paired with Antimicrobial Stewardship (ASP) Efforts
Authors: Ma Justin K , McSweeney Terrence D , McManus Dayna , Davis Matthew W , Merwede Jacob , Peaper David , Topal Jeffrey E 
Published: December 2022

Abstract

Background
Rapid microbiology diagnostic results paired with immediate ASP intervention have been shown to decrease time to OAT and improve patient outcomes. For Gram positive (GP) BSI, studies have primarily focused on Staphylococci. However, the value of using rapid diagnostics for GPC in chains is not well studied. With the use of BioFire® FilmArray® Blood Culture Identification 2 (BCID2) to identify GPC in chains, we aimed to compare the time to OAT between pre- and post- implementation.

Methods
In May 2021, our institution implemented the use of BCID2 for GPC in chains, which detects 5 types of GPC in chains to the species level and the van A/B gene. Positive results were communicated in real time 24/7 to ASP who provided recommendations on OAT to the treatment team.
A retrospective chart review compared the pre-implementation cohort (Jan - Sept 2019) to the post-implementation cohort (May 2021 - Jan 2022). The following patients were excluded from analysis: &lt; 18 years of age, presence of polymicrobial infection or Streptococci with unidentified species by BCID2, discharged or deceased before rapid diagnostic result, on comfort measures or left against medical advice within 72 hours of result.
The primary study endpoint was time to OAT which was defined as time from positive Gram stain to OAT. Secondary outcomes included percentage of ASP recommendations accepted, length of stay (LOS), and 30-day mortality.

Results
A total of 199 patients met inclusion criteria, 117 pre-cohort vs. 82 post-cohort. Baseline demographics were similar in both groups with the exception of the post-cohort having a numerically higher Charlson Comorbidity Index (Table 1). The most common sources of the bacteremias were intra-abdominal, skin and soft tissue, and endovascular (Table 2).
The primary endpoint, average time to OAT, was 35 hours in the pre-cohort and 18 hours in the post-cohort with a difference of 16.8 hours (95% CI 9.8 – 23.8; p &lt; 0.0001) (Table 3). ASP recommendations were accepted 91% of the time. The median LOS was 9 days (IQR 6 - 21) in the pre-cohort vs. 13 days (IQR 7-32) in the post-cohort (p = 0.07). The 30-day mortality rate was numerically lower in the pre-cohort (6.1% vs. 10.3%; p = 0.79).

Conclusion
For BSI due to GPC in chains, rapid diagnostics via BCID2 paired with 24/7 ASP led to markedly decreased time to OAT.

Disclosures
David Peaper, MD, Tangen Biosciences: Stocks/Bonds.
196. Repeat Tracheal Aspirates in Pediatric Intensive Care Patients: Frequency, Resistance and Antimicrobial Use
Authors: Lyon Edward , Goldman Jennifer , Lee Brian R , Selvarangan Rangaraj , Monsees Elizabeth 
Published: December 2022

Abstract

Background
Tracheal aspirates (TA) are frequently obtained in the pediatric intensive care unit (PICU); however, no data exists on the frequency or clinical management of multiple TA cultures on the same PICU patient. In this study, we describe the frequency of repeat TAs in PICU patients, the emergence of multidrug resistant organisms (MDRO), frequently cultured pathogens of TAs, and associated antibiotic prescribing patterns.

Methods
We identified 70 PICU patients between 2018-2019 who met our criteria for retrospective chart review with ≥ 2 TAs obtained during their hospitalization. The following information was collected: patient demographics, number of TAs per patient, microbiology with susceptibilities, antibiotic use, and clinical data summarizing patient condition. Descriptive statistics established the frequency and time between initial and repeat TAs, reason for collection, antibiotic exposure, and frequency of MDRO development.

Results
Preliminary data on 15 patients showed 90 total TA cultures, with a median of 4 [IQR 2.5, 8] cultures per patient during their PICU stay (Figure 1). The median days between cultures was 10 [IQR 4, 26]. Most patients were &lt; 5 years of age (n=14; 94%), male (n=13; 87%), and were admitted to the medical ICU service (n=8, 53%). Fever (46%) was the most common reason for TA collection followed by vital sign changes and secretion burden (34% and 32% respectively). A total of 133 organisms were isolated, with Pseudomonas aeruginosa (n=32), Methicillin-susceptible Staphylococcus aureus (n=16), and Klebsiella oxytoca (n=11) comprising the top pathogens (Figure 2). Eleven of the 15 patients (73.3%) had the same organism detected on ≥ 2 separate cultures. A total of 616 antibiotic days were prescribed with 149 (24%) antibiotic days prescribed for the TA result specifically. Six (40%) patients developed a MDRO after a median of 14.5 antibiotic days [IQR 11.75, 37.5]. Figure 1Number of tracheal aspirate cultures per patient
Figure 2 Frequency of identified pathogens

Conclusion
Repeat TAs are performed in the PICU, often identifying the same pathogen repeatedly, likely representing colonization. Development of resistance is common and only one-fourth of TAs are directly treated with antibiotics. These data provide an opportunity to further explore clinical criteria to maximize the impact of TA cultures in the PICU.

Disclosures
Brian R. Lee, PhD, MPH, CDC: Grant/Research Support|Merck: Grant/Research Support Rangaraj Selvarangan, BVSc, PhD, D(ABMM), FIDSA, F(AAM), BioFire: Grant/Research Support|Luminex: Grant/Research Support.
200. The Utility of a Rapid Multiplex PCR Assay in the Management of Staphylococcus Aureus Bacteremia at a Tertiary Care Center
Authors: Gholami Sherry , Chundi Vahini , Fan Katherine , Duong Lan , Kumar Princy N , Timpone Joseph G 
Published: December 2022

Abstract

Background
Staphylococcus aureus bacteremia (SAB) is a major cause of community and healthcare-acquired bacteremia and is associated with a high burden of morbidity and mortality. Appropriately tailoring management based on methicillin sensitivity can help minimize unnecessary administration of broad-spectrum antibiotics and ensure adequate treatment of MSSA/MRSA. The Verigene® (Luminex Corporation) is a multiplex PCR assay that provides rapid identification of bloodstream pathogens. We performed a QI project to determine the utility of this assay in managing patients with SAB.

Methods
We performed a single-center retrospective cohort study of positive SAB cultures from May 2020 to May 2021. Electronic health record review was conducted to abstract patient demographics, clinical characteristics, outcomes, blood culture data, and antibiotic management. Statistical analysis was done with the unpaired t-test and fishers exact test to identify associations of statistical significance.

Results
We identified 97 cases of SAB: 66% MSSA (n = 64), 34% MRSA (n = 33). Patient characteristics included: mean age 61 years, 58.8% male, 42% immunocompromised, 83.5% with ID consult, 38.1% with ICU admission, mean length of stay 20.3d, and 24.7% mortality. Using the Verigene® assay, we noted 2.6% discordance with standard microbiological technique (n = 2). The timing of Verigene® results and provider response were as follows:
The mean duration of SAB was 3.1d (MSSA = 2.8d, MRSA = 3.6d, p = 0.2477). There was a statistically significant difference in patient mortality with respect to methicillin sensitivity status: MSSA 15.6%, MRSA 42.4%, p = 0.0075, as well as mortality with ID consult 19.8% versus no ID consult 50%, p = 0.0223.

Conclusion
Despite the incorporation of a rapid multiplex PCR assay to detect bloodstream infections, the time to de-escalation for MSSA was sub-optimal (2.7 days). ID consultation continues to be an important component of SAB management as it improves patient outcomes and contributes to education of healthcare providers.

Disclosures
Lan Duong, PharmD, Johnson & Johnson: Stocks/Bonds|Lilly USA: Stocks/Bonds|Novavax: Stocks/Bonds Princy N. Kumar, MD, American Gene Technologies: Grant/Research Support|BioHaven: Grant/Research Support|Eli Lilly: Grant/Research Support|Gilead: Advisor/Consultant|Gilead: Grant/Research Support|Gilead: Stocks/Bonds|GSK: Grant/Research Support|GSK: Stocks/Bonds|Johnson&Johnson: Advisor/Consultant|Johnson&Johnson: Stocks/Bonds|Merck: Advisor/Consultant|Merck: Grant/Research Support|Merck: Stocks/Bonds|Moderna: Stocks/Bonds|Pfizer: Stocks/Bonds|Regeneron: Grant/Research Support|TheraTechnologies: Grant/Research Support|ViiV: Advisor/Consultant Joseph G. Timpone, Jr., MD, Gilead: Stocks/Bonds|Merck: Stocks/Bonds.
202. Vintage or Vogue? The Utility of Procalcitonin for Identifying Secondary Infections in Patients With Influenza or Covid-19 Receiving Extracorporeal Membrane Oxygenation
Authors: Patel Kajal D , Sobieszczyk Michal J , Marcus Joseph E , Aden James 
Published: December 2022

Abstract

Background
Secondary infections in patients receiving extracorporeal membrane oxygenation (ECMO) are difficult to identify as many signs traditionally associated with infection, such as temperature, are partially controlled by the ECMO circuit. This study analyzes the utility of procalcitonin (PCT) as a diagnostic marker in identifying secondary infections in patients receiving ECMO with influenza or COVID-19.

Methods
A single center retrospective study was performed on patients receiving ECMO with underlying influenza or COVID-19 from November 2017 to October 2021. Patient demographics, time receiving ECMO, culture data, and PCT levels were extracted. The first PCT within three days of an infection designated positive was compared to negative values, PCT extracted from patients without an identified infection or any PCT 10 days after the most recent infection. Furthermore, PCT levels were compared by type of pathogen as well as site of infection via Mann-Whitney U tests.

Results
84 patients (77% males) met inclusion criteria with median age of 43 (interquartile range (IQR): 35-51). Median ECMO time was 416 hours (IQR: 232-824), with 64 (76%) of the patients admitted for COVID-19. A total of 276 (3.3 per patient) PCT were ordered during the study period. Of the 92 infections identified, 33 (36%) had an associated PCT value with 19 (58%) PCT collected on the day of positive culture, 10 (32%) within one day, and 4 (12%) collected two to three days after positive culture. There was no significant difference between median PCT value among the infection group (1.0 IQR: 0.40-1.19) compared to the non-infectious group (1.27 IQR: 0.47-4.26, p= 0.19), between Gram-positive and Gram-negative infections (1.09 IQR: 0.43-2.70 vs. 0.95 IQR: 0.4-1.29 p= 0.35) or between bloodstream infections and respiratory infections (1.3 IQR 0.45-2.70 vs. 0.55 IQR: 0.4-1.38, p=0.35). PCT does not decline after infection is identified (Figure 1).
Procalcitonin Trends Figure 1.Procalcitonin levels do not statistically decline over the course of an infection.

Conclusion
While PCT has been proposed as a potential diagnostic marker for secondary infections in patients receiving ECMO, this single center study did not demonstrate utility of PCT in identifying secondary infections. Furthermore, there was no association of PCT levels with either the site of infection or type of infectious organism.

Disclosures
All Authors: No reported disclosures.
204. Genomic comparison of blood and colonizing nasal isolates in patients hospitalized with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia
Authors: Nadkarni Devika , Nadkarni Devika , Alburquerque Bremy , Chung Marilyn , van de Guchte Adriana , Caban Ana Berbel , Schwarz Erika Reategui , Sullivan Mitchell , van Bakel Harm , Altman Deena 
Published: December 2022

Abstract

Background
Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of health-care associated infections, particularly bloodstream infections (BSI). Concomitant colonization of the anterior nares has been shown to have implications on persistence, recurrence, and transmission events. We performed genomic comparisons between paired nasal and blood MRSA isolates obtained from the same patient to elucidate the genetic differences that may contribute to within-host invasion and virulence.

Methods
Patients hospitalized with MRSA bloodstream infection were swabbed in the bilateral nares. Paired blood and nasal isolates underwent DNA extraction and spa typing. Nasal and blood isolates from the same patients with matching spa types were sequenced by Illumina and PacBio respectively. For genomic analysis, PathoSPOT and Snippy were used to compare genomes of nasal and blood isolate pairs to evaluate single nucleotide polymorphisms, insertions and deletions.

Results
Of 121 patients with MRSA BSI, 87 patients (72%) had concomitant colonization of the anterior nares with MRSA. Spa type of t002 predominated in both blood and nasal isolates. From the 76 pairs that underwent genomic analysis, several mutated genes were identified across all pairwise comparisons, 8 of which recurred in more than one patient pair. These included genes involved in conferring antibiotic resistance, increased mutability, immune evasion, and adaptive metabolism.

Conclusion
In patients with MRSA BSI and concomitant MRSA nasal colonization, mutations identified by genomic analysis in blood-nasal pairs are implicated in contributing to invasion and within-host adaptability.

Disclosures
All Authors: No reported disclosures.
206. Using Genome-Wide Association Analysis of Pneumococcal Isolates to Identify Novel Gene Variants in Central Nervous System Infection
Authors: Sanchez John Michael , Pershing Nicole L , Nielsen Shannon , Kapusta Aurelie , Crandall Hillary , Blaschke Anne J 
Published: December 2022

Abstract

Background
Streptococcus pneumoniae is the leading cause of meningitis in children and is associated with significant morbidity and mortality. Despite conjugate pneumococcal vaccines that have otherwise been successful in reducing invasive disease caused by vaccine serotypes, the incidence of pneumococcal meningitis remains relatively unchanged. Using genome-wide association, we identified sequence elements associated with pneumococcal central nervous system (CNS) infection.

Methods
From 1996 to 2018, 366 clinical pneumococcal isolates were collected from pediatric patients and paired with clinical metadata. All isolates underwent whole-genome sequencing and in silico serotyping. Fifty-four clinical isolates were from children with CNS infection. Sequence element enrichment analysis was performed using elastic net and linear mixed modeling statistical methods to find genetic variants associated with CNS infection. We identified associated genes by mapping statistically associated variants to a serotype 19F reference S. pneumoniae genome.

Results
CNS isolates spanned 22 unique serotypes; the most common were 22F (n = 6), 7F (n = 5), 18C (n = 4), and 35B (n = 4). We identified two intergenic sequence variants and one intragenic sequence variant significantly associated with CNS infection (p &lt; 1.48 × 10-7). The top intragenic candidate in our analysis was located within cpsC, a gene involved in regulation of capsule synthesis. The CNS infection-associated cpsC variant was found in serotypes 22F (n = 1), 18C (n = 4), and 14 (n = 2).

Conclusion
The diversity of pneumococcal isolates associated with CNS infection suggests the importance of genetic determinants beyond capsular serotype. We identified a number of novel microbial genetic variants significantly associated with pneumococcal CNS infection across serotypes, including a coding mutation in cpsC. Functional characterization of cpsC variants is needed to inform mechanisms contributing to pneumococcal CNS virulence.

Disclosures
Anne J. Blaschke, MD, PhD, BioFire Diagnostics/Biomerieux: Advisor/Consultant|BioFire Diagnostics/Biomerieux: Grant/Research Support|BioFire Diagnostics/Biomerieux: IP licensed to BioFire Diagnostics through the University of Utah and royalties received through the University of Utah related to the FilmArray|Merck: Advisor/Consultant.
211. Outcomes Following a Protocol Change to decrease Perioperative Antibiotic Duration Among Liver Transplant Recipients
Authors: Brandon Hutton , Truax Crystal M , Zarate Eduardo Rodriguez , Tritle Brandon , Odrobina Robert , Imlay Hannah 
Published: December 2022

Abstract

Background
Liver transplant recipients (LTRs) are at high risk for infections. The optimal duration of perioperative antibacterial prophylaxis remains unclear, particularly in patients hospitalized prior to transplant. Our study examines the impact of a change in our institutional perioperative antibiotic protocol in LTRs on post-transplant infection and antibiotic-associated toxicity.

Methods
We conducted a retrospective cohort study of all adult LTRs at our center who underwent transplant from 1/1/2018 until 9/1/2021. Patients were categorized as low risk if they are hospitalized &lt; 24 hours prior to transplant and high risk if they were hospitalized ≥ 24 hours prior to transplant. We investigated patient outcomes after a change to our perioperative antibiotic guideline on 1/19/21, which reduced the duration of post-operative antibiotics for low risk patients from 48 to 24 hours and for high risk patients from 5 days or duration of post-operative ICU stay to 72 hours. Outcomes included post-transplant infection within 30 days (composite outcome of bacteremia and surgical site infection), C. difficile infection (CDI), and isolation of multi-drug resistant organisms (MDROs) from any site. Chi-squared and Fisher’s exact test were performed with p &lt; 0.05 considered significant.

Results
There were 154 LTRs who underwent transplantation during the study period, including 63 high risk patients (43 before and 20 after the protocol change). The median duration of prophylactic antibiotics in the high risk group decreased from 6 (IQR 5-8) to 4.5 (IQR 4-5) days after the protocol change (p = 0.04), and in the low risk group decreased from 2.5 (IQR 2-5) to 1 (IQR 1-2) day (p = 0.04). Prophylactic antibiotics consisted of piperacillin-tazobactam in 145 (94%) and vancomycin in 104 (68%) of cases. In the high risk group, infection occurred in 4 (9%) patients before and 0 patients after the protocol change (p=0.3). CDI occurred in 4 (9%) patients before and 1 (5%) patient after the protocol change (p=1). Resistant organisms were isolated in 10 (23%) patients before and 1 (5%) patient after the protocol change (p=0.15). Figure 1.Antibiotic duration as a percentage of each cohortTable 1.Clinical outcomes before and after protocol change among low and high risk patientsTable 2.Antibiotic-associated outcomes before and after protocol change among low and high risk patients

Conclusion
The policy change reduced the median duration of perioperative antibiotic prophylaxis but was not accompanied by an observed increase in postoperative infection.

Disclosures
All Authors: No reported disclosures.
214. The impact of preservation fluid culture on graft site arteritis: a systematic review and metanalysis.
Authors: Rinaldi Matteo , Bonazzetti Cecilia , Gatti Milo , Caroccia Natascia , Comai Giorgia , Ravaioli Matteo , Morelli Maria Cristina , Viale Pierluigi , Giannella Maddalena 
Published: December 2022

Abstract

Background
The role of culturing the graft preservation fluid (PF) is controversial and its impact on graft arteritis development remains unclear.

Methods
Systematic literature search retrieving all-languages observational studies comparing SOT recipients with culture positive PF versus culture negative PF. Graft site arteritis within 180 days from transplant was selected as primary outcome. Data were independently extracted using a pre-specified form, and quality of included studies was independently assessed according to ROBINS-I tool for observational studies. Meta-analysis was performed using Mantel-Haenszel random-effect models.

Results
2,492 articles were screened, and twenty-one observational studies (N=2,208 positive PF vs. 4,458 negative) were included in the meta-analyses. Among positive PF, 857 (38.8%) were classified as high-risk group pathogens (fungi, Gram negative, Enterococcus spp., beta-hemolytic streptococci and Staphylococcus aureus) and 1,351 (61.2%) as low-risk (mostly coagulase negative Staphylococci) pathogens. A significant higher risk of graft arteritis was found in SOT recipients with a PF yielding a high-risk pathogen (odds ratio [OR] 18.43, 95%CI 7.83-43.40), with low heterogeneity (I²=2.24%). Similar results were found considering separately high-risk bacteria (OR 12.02, 95%CI 4.88-29.60) and fungi (OR 71.00, 95%CI 28.07–179.56), with no heterogeneity (I²=0%), and in the subgroup analyses of liver (OR 16.78, 95%CI 2.95–95.47) and kidney (OR 19.90, 95%CI 4.78–82.79) recipients. However, data about diagnostic features of graft arteritis were very limited, indeed for only 11 of the 93 events histological or microbiological results were reported.

Conclusion
Our results may support the performance of PF culturing and a preemptive diagnostic or therapeutic management upon isolation of high-risk pathogen. Further studies based on reliable diagnosis of graft arteritis are needed to confirm our findings.

Disclosures
All Authors: No reported disclosures.