bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-1003. Group B Streptococcus Colonization in Pregnant Women and Their Infants: Prevalence of Colonization, Vertical Transmission, and Serotype Dynamics
Authors: Kwak Byung Ok , Kim Dong Hyun 
Published: January 2025

Abstract

Background
Group B Streptococcus (GBS) is a leading cause of neonatal mortality and morbidity worldwide. Despite historically lower colonization rates among pregnant Korean women compared to those in Western countries, recent studies indicate a rising trend in GBS colonization rates and serotype changes. This study aimed to investigate GBS colonization rates, vertical transmission, and serotype distribution among pregnant women and their infants in Korea.

Methods
A prospective, mother-infant paired cohort study was conducted from January 2020 to November 2023. Vaginal and rectal swabs were obtained from pregnant women, while gastric aspirate and nasopharyngeal swabs were collected from infants immediately after birth, and nasopharyngeal and rectal swabs were obtained at one and two months of age. Serotyping and multilocus sequence typing (MLST) of GBS isolates were performed.

Results
Among 427 pregnant women, 67 (15.7%) tested positive for GBS colonization. Serotype III (24%), followed by V (22.4%), VIII (19.0%), and Ib (17.2%), were the predominant serotypes, with the most common sequence types (ST) being ST2, ST19, and ST10. Vertical transmission was observed in one infant at birth, presenting with serotype V. GBS colonization was identified in four infants at one month of age, with serotypes Ia and VIII. Of these, serotype Ia persisted in two infants, while serotype III was newly detected in one infant at two months of age.

Conclusion
The increasing trend in GBS colonization among pregnant Korean women highlights the need for continuous monitoring. GBS colonization was observed in infants at birth and up to two months of age, emphasizing the importance of ongoing surveillance of GBS colonization rates and serotype distribution to establish guidelines and preventive strategies in Korea.

Disclosures
All Authors: No reported disclosures
P-1004. The Ascendance of Serotype VIII in Group B Streptococcus among Korean Women: A Detailed Examination of Serotype Distribution and Multilocus Sequence Typing
Authors: Kwak Byung Ok , Kim Dong Hyun 
Published: January 2025

Abstract

Background
Group B Streptococcus (GBS) remains a formidable agent in neonatal sepsis and meningitis, often transmitted from mothers to neonates. Despite traditionally lower colonization rates in pregnant Korean women compared to their Western peers, emerging evidence suggests an uptick in both colonization rates and serotype variability. This study endeavors to elucidate the patterns of serotype distribution and sequence types among both pregnant and non-pregnant Korean women.

Methods
We analyzed 115 specimens, comprising 72 vaginal and 43 anorectal swabs, collected from 85 pregnant and 10 non-pregnant women. Serotyping was executed via multiplex PCR, complemented by multilocus sequence typing (MLST) of the GBS isolates.

Results
In our cohort of pregnant women, the leading serotypes were VIII (24.7%), followed by V (21.2%), III (20%), Ib (12.9%), and Ia (10.6%). Lesser prevalent serotypes included II (4.7%), IV (2.4%), and VI (2.4%). The sequence types most frequently encountered were ST2 (22.4%) and ST19 (14.1%), with ST2 predominantly associated with serotype VIII, and ST19 with serotypes III and V. Among non-pregnant women, the distribution was serotype VIII and Ia (20% each), followed by Ib (20%), III, IV, and V (10% each).

Conclusion
Contrary to earlier observations, serotype VIII has now emerged as the primary serotype among Korean women, succeeded by serotypes V, III, Ib, and Ia. Our findings underscore the imperative for continued and extensive surveillance to refine our understanding of the epidemiological and serological dynamics of GBS within this population.

Disclosures
All Authors: No reported disclosures
386. Pathogen-Harboring Ticks are Prevalent in Suburban Green Spaces in Central North Carolina
Authors: Schulz Abigail , Dalton Jack , Abernathy Haley , Evans Lanya , Hicks Johnathan , Diouf Adjaratou , Giandomenico Dana , Boyce Ross M 
Published: January 2025

Abstract

Background
North Carolina (NC) reports high numbers of ehrlichiosis and spotted fever group rickettsioses. However, the prevalence of pathogens in ticks has historically been relatively low, with a &lt; 10% prevalence of Ehrlichia spp. and &lt; 1% prevalence of Rickettsia rickettsii in field-collected Amblyomma americanum and Dermacentor variabilis ticks. Most entomological surveys have focused on woodlands and rural sites, while less is known about the risk of human-tick interactions in suburban green spaces such as parks.Table 1.Pathogens identified in ticks in central North Carolina from surveillance in suburban green spaces and animal shelters.

Methods
The objective of the study, which was supported by an IDSA GERM Award, was to describe the prevalence and distribution of pathogen-harboring ticks in a suburban area of central NC with a focus on green spaces. Tick surveillance was performed by dragging vegetation in 16 suburban green spaces, primarily city and county parks, in Orange and Chatham Counties from June - August 2022. Ticks were also collected from stray dogs presenting to two county animal shelters. Polymerase chain reaction (PCR) was used to detect pathogens in the ticks.

Results
A total of 107 ticks were collected and underwent PCR testing (Table 1), including 40 collected via dragging and 67 from animal shelters. A. americanum were the most frequently encountered ticks, accounting for more than two-thirds of ticks collected in green spaces and half of ticks from shelters. A total of 26% were positive for E. chaffeensis or E. ewingii, with substantially higher infection rates among ticks from shelters. A. maculatum accounted for 25% of ticks in green spaces, half of which were positive for R. parkeri. The vast majority (90%) of D. variabilis ticks were collected from shelters, but all three ticks from green spaces were positive for R. rickettsii. While of uncertain pathogenicity, R. amblyommatis was the most frequently encountered bacterium among all ticks collected.

Conclusion
Our findings demonstrate that pathogen-infected ticks are present in suburban green spaces. Given that exposure risk of tick-borne disease is commonly associated with rural activities such as hiking, camping, and hunting, further education and public campaigns are warranted, and vector control efforts may need to be considered. Our findings also suggest that A. maculatum may be moving further inland than previously reported.

Disclosures
All Authors: No reported disclosures
P-1025. Outcome Analysis of Breakthrough Invasive Aspergillosis on Anti-Mold Azole Prophylaxis: Thirty Year Experience in Hematologic Malignancy Patients
Authors: Dagher Hiba , Chaftari Anne-Marie , Haddad Andrea , Jiang Ying , Shrestha Jishna , Sherchan Robin , Lamie Peter , Makhoul Jennifer , Chaftari Patrick , Hachem Ray Y , Raad Issam I 
Published: January 2025

Abstract

Background
In patients with haematologic malignancy (HM) and stem cell transplant recipients, Invasive Aspergillosis (IA) remains associated with a poor prognosis. Anti-mold azoles have improved the outcome of IA when used therapeutically but are extensively used as prophylaxis. There is limited data regarding the outcomes of HM patients with IA breakthroughs on anti-mold azoles. We aimed to determine whether breakthrough IA patients on anti-mold azole prophylaxis are associated with a worse outcome.

Methods
We compared baseline characteristics, antifungal therapies, and outcomes in patients with breakthrough IA between July 1993 and July 2023 who received anti-mold azole prophylaxis (group 1) versus anti-mold non-azole prophylaxis (echinocandins) (group 2) versus no anti-mold prophylaxis (group 3). We compared mortality and clinical response at 6 and 12 weeks after diagnosis.

Results
614 patients with IA were analyzed, 163 in group 1, 62 in group 2 and 389 in group 3. 42-Day all-cause mortality (45%) and IA-associated mortality (35%) were significantly higher in group 1 as compared to group 3 (33% p=0.032 & 24% p=0.02 respectively). Breakthrough IA patients in group 1 were treated with Ampho B based (AMB) primary therapy at a significantly higher rate (64%) as compared to group 3 (44% p&lt; 0.001). By multivariate analysis, AMB primary therapy was independently associated with worse response at EOT (OR= 0.64 p=0.041) and all-cause 84-day mortality (OR=1.85 p=0.002). Interestingly, anti-mold azole prophylaxis was independently associated with IA-associated and all-cause 42-day mortality (OR=1.85 p=0.009 and OR=1.70 p=0.013, respectively). Anti-mold azole primary therapy was independently associated with a successful response at EOT, protective against IA-associated and all-cause 42-day mortality, and IA- associated and all-cause 84-day mortality (p= &lt; 0.01).

Conclusion
Breakthrough IA patients receiving anti-mold azole prophylaxis are associated with a worse prognosis possibly because they are more likely switched to AMB primary therapy which is associated with a poor outcome compared to anti-mold azole therapy.

Disclosures
All Authors: No reported disclosures
P-1027. Socioeconomic Factors Associated with Adverse Outcomes in Patients with Candidemia
Authors: Iqbal Hamail , Dalkilic Ahmet , Nikolic Dejan , Palacios Carlo Foppiano 
Published: January 2025

Abstract

Background
Candidemia can be a life-threatening disease associated with multiple infectious complications, such as endocarditis and endophthalmitis. With the rise of the opioid epidemic and intravenous drug use, candidemia incidence has increased, particularly among young adult patients. While treatment standards are well-established, data on the impact of socioeconomic factors on patient outcomes is lacking. Here, we aimed to evaluate if candidemia outcomes were associated with various socioeconomic factors.

Methods
A single-center, retrospective chart review was conducted including all patients with candidemia from 2017 to 2022 at an academic medical center. We collected demographic data, culture results, treatment measures, discharge outcomes, and outcomes at 30 and 90 days. Patient census tract codes were used to evaluate socioeconomic markers from the American Community Survey (2020). Descriptive statistics, Chi-square, and Kruskal-Wallis tests were performed.

Results
237 candidemia episodes among 199 patients were included. The mean age was 54 years, 55% were male, 58% were White, and 15% were Latino. Most cases were due to C. albicans (37%), and most patients were treated with micafungin (51%). Patients who did not speak English had a higher hospital mortality (P=0.003), 30-day mortality (P=0.01), and 90-day mortality (P=0.03). Interestingly, patients with a history of substance use disorder (P=0.006) and housing insecurity (P=0.006) were less likely to die inpatient; similar trends were found for 30 and 90-day mortality. Census tract data demonstrated that patients living in areas with more people who do not speak English well were more likely to be readmitted to the hospital within 30 (P=0.02) and 90 (P=0.001) days from discharge

Conclusion
Non-English-speaking patients and those residing in census tracts with higher unemployment had higher mortality. These findings underscore the importance of considering socioeconomic and demographic factors in clinical management and public health strategies aimed at improving outcomes in Candidemia patients. Further research should explore underlying mechanisms driving such disparities.

Disclosures
All Authors: No reported disclosures
P-1031. Frequency and resistance patterns of Candida auris causing candidemia in 3 teaching hospitals in Illinois: a routine data analysis
Authors: Paredes Jose Luis , LaChance Erik , Saad Peguy 
Published: January 2025

Abstract

Background
Despite a reported increase in the prevalence of Candida auris in the US, a potential emergent multidrug-resistant health care associated pathogen, data on its prevalence and drug resistance patterns is still scarce.

Methods
Sub-analysis or routinely collected data from 3 teaching hospitals in Chicago, Illinois. Isolates from patients with positive blood cultures for any species of Candida between April 2022 and April 2024 were included. The percentage of samples positive for Candida auris, considering one isolate per patient, and the prevalence or resistance to several antifungals (echinocandins, azoles, and amphotericin B) was reported.

Results
Among 422 candidemia isolates, 210 (49.8%) were Candida auris, isolated from 64 patients: 23 (36.5%), 34 (54.0%) and 6 (9.5%) from 2022, 2023 and 2024 respectively. Four isolates (6%) were resistant to echinocandins, nine (14%) isolates were resistant to fluconazole and one (2%) was resistant to amphotericin B.

Conclusion
A large proportion of candidemia isolates were caused by Candida auris. An important percentage was resistant to fluconazole and to echinocandins, supporting amphotericin B or high dose echinocandins as first line therapy.

Disclosures
All Authors: No reported disclosures
388. Co-Testing: Increasing HIV Testing in Patients Undergoing Sexually Transmitted Infection Evaluation in a Large Integrated Healthcare Network
Authors: Seibert Allan M , Matheu Michelle M , Buckel Whitney , Moores Todd Tamara , MD Vines Caroline , Bledsoe Joseph , Balls Adam , Hellewell James , Smout Randall J , Lopansri Bert K , Stanfield Valoree K , Wormser Vanessa R , Gwiazdon Matt , Willis Park , Wallin Anthony , Hersh Adam , Patel Payal K , Webb Brandon J , Stenehjem Eddie 
Published: January 2025

Abstract

Background
Utah ranks last among states in the percentage (26.5%) of adults ever tested for Human Immunodeficiency Virus (HIV). We hypothesized that linking “co-testing” for HIV to evaluations for sexually transmitted infections (STIs) in Urgent Care (UC) and Emergency Departments (ED) would increase HIV screening. We implemented a multifaceted intervention in the UCs and EDs of our integrated health system and evaluated its impact on HIV co-testing.

Methods
The initiative included education and HIV test follow-up support along with an electronic medical record-embedded alert (Figure 1). The alert surfaced if gonorrhea (GC), chlamydia (CT), or other STI testing was ordered for patients ≥ 18 years with unknown HIV status and encouraged HIV testing if not already ordered. We sequentially implemented the initiative in 26 UC and 22 ED sites from April 2023 – December 2023. We used interrupted time series analysis to evaluate HIV co-testing rates among eligible GC/CT testing encounters in pre-implementation (April 1st, 2022 – March 31st, 2023) and post-implementation (April 1st, 2023 – March 31st, 2024) UC and ED cohorts. We compared the observed rate to the predicted counterfactual (had no intervention taken place). We also assessed co-testing by social determinants of health (SDOH) categories, alert volume, and system impact on HIV testing and diagnoses.

Results
During the 24-month study, there were 19,232 GC/CT test encounters: 5,730 UC/2,524 ED pre-implementation and 7,696 UC/3,282 ED post-implementation. In UC, the increase in the observed HIV GC/CT co-test rate vs the predicted was 14.5 percentage points (95% CI 9.08-20.06, p&lt; 0.001) (Figure 2). In the ED, the increase in the observed HIV GC/CT co-test rate vs the predicted was 13.7 percentage points (95% CI 5.75-21.71, p&lt; 0.001). HIV GC/CT co-testing varied by SDOH (Table 1). 4,704 alerts fired (54% UC/46% ED) and resulted in 730 HIV co-tests (225 UC/505 ED), representing a 15.5% engagement rate. Of these 730 alert-initiated HIV co-tests, 5 (0.7%) revealed new HIV diagnoses, representing 29% of all HIV diagnoses in UC and ED during the post-implementation period (Figure 3).

Conclusion
HIV co-testing in our UC and ED sites increased during a multifaceted initiative. New HIV diagnoses occurred in UC and ED as a result of HIV testing ordered via our alert.

Disclosures
Bert K. Lopansri, MD, D(ABMM), FIDSA, Cepheid: Grant/Research Support|Seegene: Advisor/Consultant
P-1053. Invasive Fusariosis: 5-Year Update from a Single-Center Experience in the Voriconazole Era
Authors: Kovac Victor , Baden Lindsey R , Woolley Ann E 
Published: January 2025

Abstract

Background
Invasive fusariosis is a rare but aggressive infection seen in immunocompromised patients that is often multidrug resistant. The optimal therapeutic approach in the presence of elevated MICs to standard antifungal treatment remains unknown and careful monitoring of local epidemiology of this infection is needed. We performed a retrospective review of invasive fusarium infections to help guide management at our center.

Methods
We identified all cases of invasive Fusarium infection between January 2019 and April 2024. We collected patient characteristics, including clinical presentation, therapy, and 12-week outcomes, as well as organism speciation and susceptibility testing.

Results
Seven patients were diagnosed with either proven (6, 86%) or probable (1, 14%) invasive fusariosis. The median age was 60 years and six (86%) patients were male. Four (57%) had hematologic malignancies, of which 3 (75%) received stem cell transplant, 1 (14%) idiopathic neutropenia, 1 (14%) severe burns, and 1 (14%) received solid organ transplant. Four (57%) had prolonged preceding neutropenia. Cutaneous lesions were the most common presentation (5, 71%). The four cases in neutropenic hosts had cutaneous lesions with presumed or confirmed disseminated disease involving the sinuses or lung. Three (43%) received combination therapy with voriconazole and terbinafine, 2 (29%) received posaconazole, 1 (14%) received amphotericin, and 1 (14%) received voriconazole. Fusarium solani complex was the most commonly isolated species (2, 29%). Species identification was not available in 3 cases. Susceptibility testing was available in 5 (71%) cases and MICs to voriconazole were ≥16 µg/mL and to terbinafine were ≥2. All 4 cases treated with voriconazole had elevated MICs and yet exhibited a partial (2, 50%) or complete clinical response (2, 50%) to treatment. 12-week survival was seen in 4 (57%) of cases, with one patient lost to follow-up.

Conclusion
Mortality to invasive fusariosis is high but remains similar at our center compared to the 2002-2014 period. Diagnosis remains challenging and tissue biopsy is critical. Despite elevated MICs, clinical responses to voriconazole with or without the addition of terbinafine are observed.

Disclosures
All Authors: No reported disclosures
P-1059. In vitro Activity of Gepotidacin against Klebsiella pneumoniae, Including Molecularly Characterized ESBL and Carbapenemase positive Subsets Causing Urinary Tract Infections in the United States (2019-2022)
Authors: Mendes Rodrigo E , Scullin Abigail , Kimbrough Hank , Hubler Cory , Kapoor Renuka , Torumkuney Didem , Ryan Arends S J 
Published: January 2025

Abstract

Background
Gepotidacin (GEP) is a novel, bactericidal, first-in-class triazaacenaphthylene antibacterial that inhibits bacterial DNA replication by a unique mechanism of action, distinct binding site, and provides well-balanced inhibition (for most uncomplicated urinary tract infection [uUTI] uropathogens and Neisseria gonorrhoeae) of two different type II topoisomerase enzymes. GEP recently completed two phase 3 trials for the treatment of uUTI. This study reports the activity of GEP and other oral antibacterials against K. pneumoniae, including molecularly characterized ESBL and carbapenemase producing isolates collected from UTI patients in the US.

Methods
A total of 2,001 K. pneumoniae were collected from 73 sites. CLSI methods were used for both susceptibility testing and MIC interpretation. Isolates with aztreonam, ceftazidime, ceftriaxone or meropenem MIC of ≥2 mg/L were subjected to genome sequencing, and screening of plasmid-mediated AmpC (pAmpC), ESBL, and carbapenemase genes.

Results
A total of 11.0% (220/2,001) K. pneumoniae were screened for β-lactamase genes (Table). Majority of these isolates carried blaCTX-M alone (78.2%; 172/220), and a small number carried combinations of blaCTX-M and ESBL variants of blaSHV (2.7%; 6/220), blaSHV alone (2.7%; 6/220), or pAmpC alone (2.3%; 5/220). Among screened isolates, 9.1% (20/220) carried carbapenemases. GEP had MIC50 and MIC90 of 4 mg/L and 8 mg/L, respectively, against isolates that did not meet the MIC criteria for screening of β-lactamases. Other oral agents showed susceptibilities of 92.8–99.5% against this group, except for nitrofurantoin (35.7%). GEP had an MIC90 of 32 mg/L against screened strains carrying ESBL and pAMPC, and an MIC90 of 16 mg/L against carbapenemase positive isolates. Other oral agents had limited activity (&lt; 42%) against strains carrying ESBL and/or pAMPC.

Conclusion
GEP showed activity against UTI-causing K. pneumoniae in US medical centers, including against isolates carrying ESBL, pAmpC and/or carbapenemases. These data support further clinical development of GEP as a potential treatment option for uUTI caused by K. pneumoniae including when other oral treatment options have limited activity due to drug resistance.

Disclosures
Rodrigo E. Mendes, PhD, GSK: Grant/Research Support Renuka Kapoor, PhD, GSK: Employee|GSK: Stocks/Bonds (Public Company) Didem Torumkuney, PhD, GSK: Employee|GSK: Stocks/Bonds (Public Company)
P-1060. In vitro Activity of Gepotidacin Tested Against Molecularly Characterized Escherichia coli Isolates Responsible for Urinary Tract Infections in the US (2019-2022)
Authors: Mendes Rodrigo E , Beekman Danielle , Scullin Abigail , Karr Maura , Kapoor Renuka , Torumkuney Didem , Ryan Arends S J 
Published: January 2025

Abstract

Background
Gepotidacin (GEP) is a novel, bactericidal, first-in-class triazaacenaphthylene antibacterial that inhibits bacterial DNA replication by a unique mechanism of action, distinct binding site and provides well-balanced inhibition (for most uncomplicated urinary tract infections [uUTI] uropathogens and Neisseria gonorrhoeae) of two different type II topoisomerase enzymes GEP completed two phase 3 trials for treatment of uUTI This study reports the activity of GEP and other oral antibacterials against E. coli (EC), including molecularly characterized isolates carrying ESBL and carbapenemase genes collected from UTI patients in the US.

Methods
3,995 EC collected from 52 US sites as part of the gepotidacin uropathogen global surveillance study were included (2019-2022). CLSI methods were used for susceptibility (S) testing and MIC interpretations. Isolates with aztreonam, ceftazidime, ceftriaxone or meropenem MIC of ≥2 mg/L were subjected to genome sequencing, and screening of β-lactamase genes and epidemiology typing (MLST, O:H, and fimH).

Results
A total of 86.2% (3,444/3,995) of EC did not meet the MIC criteria for molecular characterization (Table) and had GEP MIC50 and MIC90 values of 2 mg/L and 4 mg/L, respectively. Cefazolin (97.0%S), fosfomycin (FOS) (99.7%S), and nitrofurantoin (NIT) (98.7%S) had activity among oral comparator agents tested against this group. A total of 13.8% (551/3,995) of EC were screened for β-lactamase genes, and this group had GEP MIC50 and MIC90 values of 2 mg/L and 4 mg/L respectively. Other oral agents had limited activity, except for FOS (98.0%S) and NIT (92.7%S). In general, GEP retained activity with MIC50 and MIC90 values of 2 mg/L and 4 mg/L, respectively, against isolates carrying ESBL, AmpC and carbapenemase genes, and against clonal complex (CC) 131 and the resistant subset O25b:H4.

Conclusion
GEP showed generally consistent activity against UTI-causing EC in the US, including against isolates carrying ESBL, AmpC and/or carbapenemase genes. In addition, GEP had activity against the CC131 high-risk EC clone. These data support further clinical development of GEP as a potential treatment option for uUTI caused by EC including when other oral treatment options are limited due to drug resistance.

Disclosures
Rodrigo E. Mendes, PhD, GSK: Grant/Research Support Renuka Kapoor, PhD, GSK: Employee|GSK: Stocks/Bonds (Public Company) Didem Torumkuney, PhD, GSK: Employee|GSK: Stocks/Bonds (Public Company)