bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-2250. Metagenomic Next Generation Sequencing Enhances Rickettsial Infection Diagnosis in Patients with Acute Undifferentiated Fever
Authors: Weiss Sonja , Phoompoung Pakpoom , Yamaguchi Julie , Berg Michael G , Averhoff Francisco , Cloherty Gavin , Suputtamongkol Yupin 
Published: January 2025

Abstract

Background
Murine and scrub typhus are common causes of acute undifferentiated fever (AUF) in tropical regions, after malaria, dengue fever, and typhoid fever have been ruled out. While indirect immunofluorescence assay (IFA) can diagnose both diseases, accuracy depends on when the sample is collected. To improve detection, we used unbiased metagenomic Next Generation Sequencing (mNGS) on 969 AUF patient samples with negative IFA results from Siriraj Hospital, Bangkok, Thailand collected between 2015 and 2021.

Methods
Plasma was pre-treated with benzonase before extraction on an Abbott m2000 instrument. mNGS libraries were prepared from double-stranded cDNA with Illumina Nextera XT reagents then sequenced on a NextSeq. Reads were taxonomically classified by Abbott pipelines SURPI or DiVir and mapped in CLC Bio Genomics Workbench (Qiagen, Inc).

Results
During the study period, a total of 2,465 samples were analyzed by IFA, identifying 58 (2.4%) cases of murine typhus and 26 (1.2%) cases of scrub typhus. Among IFA negative samples, mNGS identified Rickettsia spp. in 27 cases (2.8%), including R. typhi (murine typhus) (n=19), R. felis (n=5), and R. rickettsii, R. prowazaki, and R. australis (n=1 each). Notably, mNGS identified Orientia tsutsugamushi (scrub typhus) in one sample missed by IFA.
For patients with mNGS-detected R. typhi, serological confirmation was achieved in 2 cases. Another 13 were classified as probable based on clinical presentation, while 4 cases lacked conclusive clinical correlation. For patients with R. felis identified by mNGS, 4/5 had confirmed or probable diagnoses based on clinical symptoms. The inconclusive case was a 65-year-old man with a urinary tract infection who died from sepsis for which mNGS revealed a co-infection with R. felis and Serratia marcescens. Interestingly, none of the mNGS positives for R. rickettsii, R. australis, and R. prowazaki had clinical presentations that supported the diagnoses.

Conclusion
mNGS significantly enhances the diagnosis of rickettsial infections, particularly for murine typhus. This improved diagnostic capability provided by mNGS holds promise for improved management of AUF patients, potentially reducing unnecessary testing and inappropriate antibiotic use.

Disclosures
Sonja Weiss, BS, Abbott Laboratories: Employee Julie Yamaguchi, BS, Abbott Laboratories: Employee Michael G. Berg, PhD, Abbott Laboratories: employee|Abbott Laboratories: Stocks/Bonds (Public Company) Francisco Averhoff, MD, MPH, Abbott Laboratories: Employee Gavin Cloherty, PhD, Abbott Laboratories: Employee
P-2255. Peri-Transplant Antibiotic Use and Multidrug Resistant Infections in Liver Transplantation
Authors: Contag Caitlin A , Deng YaoWei , Rodriguez-Nava Guillermo , Zimmet Alex , Shen Sa , Nelson Joanna K , Subramanian Aruna , Kwong Allison , Ferguson Jessica 
Published: January 2025

Abstract

Background
Understanding antibiotic use patterns and risk of infection with multi-drug resistant organisms (MDROs) in the peri-transplant period is crucial to successful post-liver transplant care.

Methods
Clinical data from patients who underwent liver transplant after the initiation of ICD-10 coding were obtained using Stanford University’s central database. Data were processed and analyzed in R studio and Excel.

Results
During the study period, 645 patients underwent liver transplantation. The median age at transplantation was 60.8 years (IQR 18.9, 82.4) and 222/645 (34%) were female. In the 30-day pre-transplant period, 21/645 (3%) patients developed bacteremia or fungemia, and in the 30-day post-transplant period, 30/645 (5%) patients developed bacteremia or fungemia. Enterococcus faecium was the most common cause of bacteremia (25/60 positive blood cultures), followed by enteric gram-negative rods (16/60 positive blood cultures). All E. faecium causing bacteremia was vancomycin resistant (25/25, 100%), and 9/16 (56%) gram negative rod isolates from blood were MDROs.
The overall antibiotic days per thousand inpatient days in the 30-day pre- and post-transplant period was 374. The most used group of antimicrobials was anti-Pseudomonal β-lactams, with 255.4 days of use per thousand inpatient days (Figure 1). Vancomycin had 83.8 days of use per thousand inpatient days but was more frequently used in patients who had an MDRO isolated from at least one body site than in patients who did not have an MDRO isolated (104.7 days vs 76.8 days per thousand inpatient days).
Patients with at least one MDRO isolated 30 days pre- or post-transplant had significantly higher 90-day and 1-year mortality compared with patients who had positive cultures but did not have an MDRO isolated (12.1% vs 1.8%, p=0.01; 17.6% vs 7.3%, p=0.02), as well as a longer length of post-transplant hospitalization that did not meet statistical significance (14.3 days vs 10.8 days, Table 1).

Conclusion
Liver transplant patients are at high risk for colonization and infection with MDROs in the peri-transplant period and have high rates of antimicrobial use. For this patient cohort, presence of an MDRO is associated with higher rates of mortality and longer lengths of stay in the post-transplant period.

Disclosures
All Authors: No reported disclosures
P-2298. Daily Single-strength vs. Thrice-weekly Double-strength Trimethoprim/sulfamethoxazole for Pneumocystis jirovecii Prophylaxis in Kidney Transplant Recipients: A Non-inferiority Randomized Controlled trial
Authors: Chantapoh Wittawin , Kantachuvesiri Surasak , Sutharattanapong Napan , Bruminhent Jackrapong 
Published: January 2025

Abstract

Background
Pneumocystis jirovecii pneumonia (PCP) is commonly encountered among kidney transplant (KT) recipients. Either daily or thrice-weekly, single strength (SS) or double strength (DS) trimethoprim/sulfamethoxazole (TMP/SMX) is recommended after KT to prevent PCP. However, a direct comparison between these regimens in terms of PCP prevention is lacking. We assessed the efficacy of SS daily (DSS) versus DS thrice weekly (TDS) TMP/SMX prophylaxis for PCP within the first 6 months post-transplant in KT recipients.

Methods
We conducted a single-center block of 4 randomized, open-label, non-inferiority, randomized controlled trial at a single transplant center between December 2022 and December 2023. All KT recipients 15 years and older were included. The single-strength group received TMP/SMX 80/400 mg daily after KT, while the double-strength group received two tablets of SS doses thrice weekly. PCP occurrence was observed for 6 months, and side effects of TMP/SMX and ease of drug consumption were monitored.

Results
A total of 65 KT recipients were included. The participants had a mean age (SD) of 46 (11) years old, with the following proportion: male gender (58%), deceased donor KT (20%), anti-thymocyte globulin as induction therapy (17%), and CMV seropositivity (95%). There were 32 and 33 KT recipients assigned to the DSS and TDS groups, respectively. Baseline characteristics between the two groups were comparable. At 6 months after transplant, all patients remained free from PCP in both groups. There was a non-significant lower mean (SD) of white blood cell counts in the DSS group compared to the TDS group [6,235 (2,271) vs.7,052 (2,464) cells/mm3, p = 0.23], respectively. In parallel, there was no significant difference in terms of hepatotoxicity or renal dysfunction among those groups. According to per-protocol analysis, 27 (96%) of the DSS group reported having convenient administration of the drug compared to 18 (100%) of the TDS group (p = 0.60).

Conclusion
TMP/SMX appears to efficiently prevent PCP in the early period after KT. Both SS daily and DS thrice-weekly regimens seem to be comparable in terms of effectiveness, tolerability, and compliance. Further studies with larger samples are encouraged to support this result. TCTR20240329004.

Disclosures
All Authors: No reported disclosures
P-42. Systematic review and meta-analysis of recombinant herpes zoster vaccine in immunocompromised populations
Authors: Marra Fawziah , Yip Michael , Cragg Jacquelyn , Vadlamudi Nirma K 
Published: January 2025

Abstract

Background
Herpes zoster infection is common in immunocompromised individuals. Recently, the Advisory Committee on Immunization Practices recommended immunizing with the recombinant zoster vaccine (RZV).

Methods
Objective: To evaluate the efficacy, immunogenicity and safety of RZV in immunocompromised individuals, such as transplant recipients, cancer patients undergoing chemotherapy, individuals with preexisting autoimmune diseases and HIV-infected patients.
Data Sources and Study Selection: From January 1984 to October 2023, a systematic search of PubMed, MEDLINE, EMBASE, Scopus, Web of Science, CINAHL, and Cochrane CENTRAL was performed. Randomized clinical trials (RCT) evaluating RZV compared to placebo in immunocompromised adults were selected.
Data Extraction and Synthesis: Study characteristics and estimates on the incidence of herpes zoster, humoral and cellular immune responses, and safety data were extracted from studies. Estimates were pooled using random-effects meta-analysis. Differences by study-level characteristics were estimated using subgroup meta-analysis and metaregression.

Results
Seven RCTs were included. Compared to placebo, RZV reduced the incidence of herpes zoster across all ages by 81% (RR: 0.19, 95%CI: 0.09, 0.44), with moderate heterogeneity across the studies (I2 = 60.49%; τ2 = 0.31; P=0.07). RZV significantly increased humoral and cellular immunity one month after the last dose. Transplant and past malignancy were associated with lower immunogenicity. RZV was more reactogenic with more local and systemic adverse events. There was no difference in serious adverse events or death between the vaccine and placebo arms.

Conclusion
This study suggests that RZV reduces the risk of herpes zoster infection in immunocompromised individuals. This vaccine should be routinely offered to immunocompromised individuals, preferably before chemotherapy or treatment.

Disclosures
All Authors: No reported disclosures
P-67. Safety of Omadacycline Versus Standard-of-Care Oral Antibiotic Treatment for Bone and Joint Infections: Interim Results from an Open-Label, Non- Inferiority, Randomized Controlled Trial
Authors: Kang Amy Y , Garcia Delgado Guarina , Phan Tran Donna , Flores Evelyn A , Romo-Kozan Vanessa , Payan Isabel , Miller Loren G 
Published: January 2025

Abstract

Background
The incidence of bone and joint infections (BJIs) continues to increase, and existing oral BJI antibiotics have limitations. Omadacycline may be a potential treatment option for BJI treatment due to activity against doxycycline-resistant S. aureus and ESBL-producing Enterobacterales for which there are often no viable oral options. However, the safety of omadacycline in this setting is poorly defined.

Methods
We performed an open label, randomized, controlled clinical trial of adults with BJIs in the outpatient setting. Participants were randomized to omadacycline-containing regimen (omadacycline 300mg po daily) or Standard-of-Care (SOC) antibiotics. Adjunctive antibiotics were permitted in addition to omadacycline. Safety labs were performed at regular intervals. Herein, we report an interim, descriptive analysis of safety data.

Results
Among the 59 participants enrolled to date, 31 (53%) were randomized to the omadacycline-containing regimen and 28 (47%) to SOC. Median age was 58 years old, 52 (88%) were male, 44 (75%) identified as Hispanic, 8 (14%) as African-American, and 4 (6%) as white. The most common BJIs were diabetic foot infections (52, 88%) and device infections (5, 8%). (Table) Combination therapy was used in 16 (52%) vs. 12 (43%) in the omadacycline-containing vs. SOC arms, and IV only therapy was used in 0 (%) vs. 5 (18%) in the two arms, respectively. Most commonly used SOC regimens included ciprofloxacin (8, 29%), doxycycline (7, 25%), amoxicillin/clavulanate (6, 21%), and levofloxacin (3, 11%). Commonly associated laboratory abnormalities included new or worsening renal insufficiency (2 (6%) in the omadacycline-containing arm vs. 5 (18%) in SOC) and transaminitis (2 (6%) vs. 4 (14%)). Adverse events were similar in the omadacycline-containing vs. SOC arms including nausea (6 (19%) vs. 4 (14%)), vomiting (0 (0%) vs. 4 (14%)), and diarrhea (5 (16%) vs. 2 (7%)). (Table) There was 1 drug-related serious adverse event in the omadacycline-containing arm due to likely hypersensitivity to omadacycline; the event resolved after drug discontinuation.

Conclusion
In this interim analysis of our ongoing trial, the safety of omadacycline for BJI appears to be similar to the SOC. More robust data on long-term safety is warranted.

Disclosures
Amy Y. Kang, Pharm.D., BCIDP, Paratek Pharmaceutical: Grant/Research Support Loren G. Miller, MD MPH, Armata: Grant/Research Support|Contrafect: Grant/Research Support|GSK: Grant/Research Support|Merck: Grant/Research Support|Paratek: Grant/Research Support
P-84. Microbiologic and histologic concordance of pedal osteomyelitis and association with infection progression
Authors: Maier Marissa , Bajema Kristina L , Madrid-Morales Julieta , Bosch Robert 
Published: January 2025

Abstract

Background
Diabetes-related infections and peripheral artery disease are the leading causes of foot amputation worldwide, resulting in significant morbidity and mortality. Clinical management practices vary widely. We sought to describe the concordance of microbiology and pathology results among persons undergoing forefoot or midfoot bone resection.

Methods
We conducted a retrospective cohort study of adults in Veteran’s Administration (VA) care who underwent forefoot or midfoot bone debridement at VA Portland from January 1, 2017 through December 31, 2019. We used VA’s Corporate Data Warehouse, a centralized database with comprehensive demographic and clinical data, and obtained additional clinical information through chart review. We excluded patients who underwent hindfoot debridement, or intervention on the ipsilateral foot within the preceding year. We defined positive pathology as acute or chronic osteomyelitis and positive microbiology as any bacterial growth from the resection clean margin. Descriptive analyses included calculation of the proportion of individuals with both microbiology and pathology results available versus microbiology or pathology results alone.

Results
From January 1, 2017 – December 31, 2019, there were 379 eligible resections performed among 343 patients, who were 97% male, 82% white, and with median age 69 years. Of the 379 resections, 44% (N=167) had both microbiology and pathology results, 11% (N=44) had microbiology alone, and 45% (N=172) had pathology alone.
Of resections with both microbiology and pathology results, 87% (146/167) had bacterial growth and 58% (97/167) had osteomyelitis on pathology; bacterial growth was present in 90.7% and 82.6% of specimens with and without osteomyelitis on pathology, respectively. Of those with microbiology alone, 93% (41/44) had bacterial growth. Of those with pathology alone, 50% (87/172) had osteomyelitis on pathology.

Conclusion
Similar proportions of bacterial growth were observed whether pathology evidence of osteomyelitis was present. The utility of microbiology results alone to inform antibiotic treatment decisions requires further study.

Disclosures
All Authors: No reported disclosures
P-96. Efficacy and Safety of Lactobacillus reuteri Supplementation Combined with Triple Therapy for Eradicating Helicobacter pylori: An Updated Meta-Analysis of Randomized Controlled Trials
Authors: Elkoumi Omar , Elkoumi Ahmed , Khaled Elbairy Mariam , Khaled Elnegiry Amr , Ghanem Ahmed 
Published: January 2025

Abstract

Background
The efficacy of Helicobacter pylori (H. pylori) triple therapy is declining over time. Lactobacillus reuteri (L. reuteri) is a probiotic that has shown promising results for eradicating H. pylori and decreasing adverse events. We aim to assess the efficacy of adding L. reuteri to the standard triple therapy for H. pylori eradication.

Methods
We systematically searched PubMed, Embase, Cochrane Central, Web of Science (WOS), and Scopus databases from inception until May 2nd, 2024. We included any randomized controlled trial comparing individuals receiving viable L. reuteri or a placebo preceding, during, or after the standard triple therapy for H. pylori eradication. We used Review Manager 5.4 for all statistical analyses.

Results
Seven randomized controlled trials with a total of 518 patients were included in the meta-analysis. We found that patients who received L. reuteri added to their triple therapy showed a higher eradication rate than those with triple therapy alone (HR: 1.16, 95% CI [1.03, 1.31], p = 0.01). The pooled results showed that the addition of L. reuteri to the triple therapy resulted in a significantly lower risk of taste distortion (RR: 0.59, 95% CI [0.39, 0.90], p = 0.01), diarrhea (HR: 0.44, 95% CI [0.28, 0.71], p = 0.0007), and constipation (HR: 0.52, 95% CI [0.31, 0.87], p = 0.01). There was no difference between both groups in experiencing epigastric pain (HR: 0.62, 95% CI [0.29, 1.33], p = 0.22), or nausea/vomiting (HR: 0.61, 95% CI [0.16, 2.40], p = 0.48).

Conclusion
In contrast to a previous meta-analysis, L. reutri supplementation improved the H. pylori eradication rate. Adding L. reuteri to the triple therapy decreased diarrhea, constipation, and taste distortion compared to the standard triple therapy alone. To reinforce our conclusions, further clinical trials with larger sample sizes are required.

Disclosures
All Authors: No reported disclosures
P-104. Impact of Sepsis-Induced Cardiomyopathy on Clinical Outcomes in Sepsis Patients
Authors: Wan Kim Tae , Ko Ryoung-Eun 
Published: January 2025

Abstract

Background
Despite the known impact of cardiac function on sepsis outcomes, there is limited understanding of how ejection fraction (EF) influences hospital mortality in patients with sepsis-induced cardiomyopathy. This study assesses the severity of cardiac dysfunction determined by echocardiography within the first 24 hours of sepsis diagnosis on hospital mortality.

Methods
In this retrospective cohort study, 2,504 patients diagnosed with sepsis and who underwent echocardiography within 24 hours were analyzed. Based on EF, patients were classified into normal (EF ≥ 50%), moderate dysfunction (30% ≤ EF &lt; 50%), and severe dysfunction (EF &lt; 30%). The primary outcome was hospital mortality. Multivariable logistic regression was employed to identify factors associated with increased mortality, adjusting for clinically and statistically significant variables.

Results
Among the study patients, 1,803 (72%) had a normal EF, 356 (14.2%) had moderate dysfunction, and 115 (4.6%) had severe dysfunction. The hospital mortality was significantly higher in the severe dysfunction group at 40.0%, compared to 29.5% in moderate and 25.7% in normal EF groups (P=0.023). In multivariable analysis, severe cardiac dysfunction, inappropriate initial antibiotic therapy, and certain sites of infection were significantly associated with increased hospital mortality.

Conclusion
The decreased EF among sepsis patients is correlated with increased organ failure and higher mortality rates compared to patients with normal cardiac function.

Disclosures
All Authors: No reported disclosures
P-145. Parasitological characterization of stool samples from indigenous Wayuu children from La Guajira, Colombia
Authors: Carolina Hernandez Derly , Judith Benavides Clara , Tatiana Saenz Angie , Sanchez Gil Maria Valentina , Ariza Marín Diego Sebastian , Hernandez Diaz Tatiana Alejandra 
Published: January 2025

Abstract

Background
La Guajira, 396,511 children and most of them recognized as Wayuu indigenous population. They have many public health problems in primary services. This children are at high risk of suffering from intestinal parasitosis. The most common are Entamoeba histolytica (EH) and Giardia duodenalis (GD) in their infectious forms. The common source is contaminated food and water. Geohelminth (GH) infections can be complicated by pulmonary compromise and worsening health of children with nutritional problems. In Colombia, primary care for intestinal parasitosis is albendazole. As part of the social interest we want to know the main species that we can find in the feces of a group of these children to know if primary treatment with albendazole is sufficient.
Coccidial structures by Ziehl-Neelsen (ZN)

Methods
Descriptive cross-sectional study. On December 2023 was assessing 44 coprological samples. Containers were labelled, consent and informed assent were signed. They were preserved in MIF reagent and stored at 4°C, processed by Formalin-Gasoline (F-G) with the addition of parasitological lugol for microscopic evaluation under 10x and 40x objectives. Coccidial structures were observed by Ziehl-Neelsen (ZN) staining with a 100x objective, both calibrated with a micrometer. The variables was analized by frequencies and measures of central tendency.
Trophozoite of Entamoeba histolytica

Results
44 samples were included. Abnormal results were found in 42/44 (95.5%) by ZN technique; 44 (95.5%) Microsporidium and 23 (52.3%) Cryptosporidium. In the F-G and addition of parasitological lugol, abnormal results were found in 38/44 (86.4%). Regarding Protozoa, 18 (40.9%) were found GD cysts, 36 (81.8%) B. hominis, 8 (18.2%) E. nana, 12 (27.3%) EH trophozoites and 2 (4.5%) C. Mesnili. Regarding GH, 2 (4.5%) were found with S. stercoralis and A. lumbricoides and 1 (2.3%) H. nana. Both ZN staining and parasitological lugol staining showed 19 (43.2%)C. cayetanensis and 14 (31.9%) C. belli.
Cysts of Giardia Duodenalis

Conclusion
The frequency of PI was 95.5%, 42 (95.5%) protozoan and 5 (11.4%) GH. The most frequent isolates were Microsporidium, B. hominis and GD. Perhaps we could offer another deworming treatment in this population. This description could be the basis for other studies in this population to offer better alternatives and make the public health situation in this scenario more visible to the government.
Egg of Hymenolepis nana

Disclosures
All Authors: No reported disclosures