bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-531. Mitochondrial DNA Haplogroups and Circulating Immune Cell Phenotypes in Veterans with and without HIV
Authors: Yan Aiwei , Kundu Suman , Samuels David , Bailin Samuel S , Xu Ke , So-Armah Kaku , Butt Adeel A , Gerschenson Mariana , Goetz Matthew B , Tracy Russell , Marconi Vincent , Justice Amy , Freiberg Matthew , Koethe John R , Hulgan Todd 
Published: January 2025

Abstract

Background
HIV infection and mitochondrial function both influence cellular immune responses, but little is known about this relationship. We examined associations between mitochondrial DNA (mtDNA) haplogroups and peripheral blood mononuclear cell (PBMC) phenotypes among people with HIV (PWH) and without HIV in the Veterans Aging Cohort Study Biomarker Cohort (VACS-BC).

Methods
VACS-BC participants had mtDNA haplogroups determined from genome-wide genotyping and PBMC phenotyping by flow cytometry. Analyses included Kruskal-Wallis and Wilcoxon rank sum tests stratified by self-reported ancestry (non-Hispanic Black or White) and HIV status. Significant univariate associations were assessed in linear regression models adjusted for age and plasma viral load &lt; 50 copies/mL among PWH. These exploratory analyses were not corrected for multiple comparisons.

Results
1939 Veterans (1266 PWH; 95% male; median age 52 years [range 25-91]) had data available. In Black PWH (N=991), African haplogroup L3 was associated with lower % senescent (CD28-negative) CD4+ T cells (p=0.05), and haplogroup L2 was associated with higher % TEMRA CD8+ T-cells (p=0.03). In White PWH (N=275), European haplogroup T was associated with lower % CD38+ CD4+ T-cells (p=0.02) and haplogroup J with lower % IL4+ CD4+ T-cells (p=0.001). Haplogroups T and J were also associated with lower (p=0.05) and higher (p=0.02) % transitional memory CD8+ T-cells, respectively. Different age-adjusted associations were seen in Veterans without HIV, with the most prominent between haplogroups T and L1 and lower % total (CD14+) and classic (CD14+/CD16-) monocytes (p-value range=0.02-0.005).

Conclusion
MtDNA haplogroups were associated with cellular phenotypes, and associations differed by HIV status. Notable findings among PWH were in senescent, CD38+, and IL4-producing CD4+, and effector memory CD8+ T-cells, all important components of immune responses to viral infection. Haplogroup associations with monocyte populations in persons without HIV are intriguing and deserve further study. Limitations include those inherent in PBMC flow cytometry, cross sectional design, and small sample sizes for some subgroups. Validation in independent cohorts and mechanistic studies are needed.

Disclosures
Adeel A. Butt, MD, MS, Gilead Sciences: Grant/Research Support John R. Koethe, MD, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Grant/Research Support|Merck & Co.: Advisor/Consultant|Merck & Co.: Grant/Research Support
P-543. A Descriptive Report of Discontinuation Rates, Blips, and Viremia Associated with Cabotegravir/Rilpivirine at One Ryan White HIV/AIDS Program-funded site in Northern Virginia
Authors: Prather Caitlin , Richey Katie , Verderese John Paul 
Published: January 2025

Abstract

Background
Cabotegravir/rilpivirine (CAB/RPV) is the first and only long-acting complete regimen for the treatment of HIV-1 infection. Rates of discontinuation, viral blips, and viremia were low in Phase III clinical trials for CAB/RPV, but data from additional locations in real-world conditions remains lacking. This descriptive report explores the frequency of these occurrences in patients treated with CAB/RPV at one Ryan White HIV/AIDS Program (RWHAP)-funded site.

Methods
This was a single-center, retrospective, observational chart review of people living with HIV at one institution in Northern Virginia. Patients were included if they received at least one dose of injectable CAB/RPV between January 2021 and April 2024. Data collected from the electronic medical record included demographics, body mass index (BMI), history of antiretroviral drug mutations, HIV viral load, and HIV treatment history.

Results
A total of 107 patients were included in this study with a mean age of 45 years. Of these, 2% were assigned female at birth and 49% were Black. In the study period, 16% of patients discontinued the medication. The most common causes for discontinuation were adverse effects, insurance denials, patient preference for oral therapy, and frequently missing appointments. Of the 17 patients who discontinued therapy, only one was discontinued due to virologic failure. As of April 2024, 85 patients remain on CAB/RPV. Of these, 43% have experienced at least one blip, 25% have experienced low-level viremia, and 61% have experienced either a blip or low-level viremia since starting CAB/RPV. Duration of therapy ranged from 1 to 1020 days (average 579 days) since first injection and longer duration of therapy weakly correlated with prevalence of blips or viremia. 92% of doses have been administered within the allowable 14-day treatment window. There was no significant difference between BMI at the start of treatment to April 2024.

Conclusion
Among patients treated with CAB/RPV, viral blips and low-level viremia are common but are not associated with treatment discontinuation or treatment failure. Rates of discontinuation due to adverse effects were higher than what was observed in Phase III randomized controlled trials of CAB/RPV, though treatment failure was uncommon as expected.

Disclosures
All Authors: No reported disclosures
P-548. Higher rate of two-drug regimen discontinuation due to reasons unrelated to virologic failure among people with HIV aged 50 years or above
Authors: Tang Tommy , Kwong Tsz Shan , Chan Philip , Lam K W , Chan Helen , Choy Annabel K T , Chu M Y , Fong Jason , Lam Wilson , Leung W S , Ting W M , Wu T C , Yung S K , Lee M P 
Published: January 2025

Abstract

Background
Previous studies demonstrated that integrase strand transfer inhibitor (INSTI)-based two-drug regimens (2DRs) reliably maintain HIV suppression. Corresponding data in older people with HIV (PWH) remain limited. This retrospective study compared the real-world maintenance outcomes of INSTI-based 2DRs between PWH aged 50 or above (PWH &gt;=50) and those below 50 years (PWH&lt; 50). It was approved by the Research and Ethics Committee, Kowloon Central/Kowloon East Cluster, Hospital Authority (KC/KE-23-0195/ER-4).

Methods
PWH who switched from suppressive standard three-drug antiretroviral therapy (ART) to oral INSTI-based 2DRs at the HIV Clinic of the Queen Elizabeth Hospital, Hong Kong, China were identified through electronic records. The formulations of 2DRs and outcomes of those who reached 96 weeks after switch, before 1 March 2024 were retrieved. HIV suppression and virologic failure (VF) were defined as plasma HIV-1 RNA &lt; 50 copies/mL and &gt;200 copies/mL respectively.

Results
Since January 2014, 237 PWH switched to INSTI-based 2DRs. Their pre-switch characteristics are summarized in Table 1. On 29 February 2024, 96 weeks has lapsed from their 2DR switch dates in 87 PWH&lt; 50 and 101 PWH &gt;=50. Eight (4.3%) of them died due to causes unrelated to HIV. Twenty-two of them (11.7%) discontinued 2DRs during the 96-week period: six (6.9%) were PWH&lt; 50 and 16 (15.8%) were PWH &gt;=50, with reasons summarized in Table 2.
By log-rank test, PWH &gt;=50 trended toward significance for a higher risk of 2DR discontinuation when compared to PWH&lt; 50 (p=0.058) (Figure 1). VF occurred in only 3 (1.6%) users, with similar rates between both groups (p=1). One PWH&lt; 50 developed VF due to non-adherence, continued 2DR and achieved subsequent viral suppression. Another two had negative drug resistance mutation tests afterwards. 2DRs discontinuation due to non-VF causes was numerically higher in the PWH &gt;=50 group without statistical significance (p=0.06).Figure 1.Kaplan-Meier estimator for the cumulative risk of 2DR discontinuation

Conclusion
In this real-world study comparing the maintenance outcomes of virally suppressed PWH who switched to INSTI-based 2DRs, occurrence of VF was uncommon in both older and younger PWH. However, discontinuation due to non-VF causes was more common in older PWH above 50 years old than those below, with a majority contributed by intolerance and non-HIV deaths.

Disclosures
Wilson Lam, n/a, Gilead: Advisor/Consultant|Gilead: Honoraria|GSK: Advisor/Consultant|GSK: Honoraria|Moderna: Honoraria|Pfizer: Conference sponsor
P-609. Assessment of Parents’ Awareness and Attitudes towards Respiratory Syncytial Virus and its Prevention in the US
Authors: Choi Yoonyoung , Berjonneau Erwan , DWYER Brian , Chun Bianca , Petigara Tanaz , Guillaume Xavier 
Published: January 2025

Abstract

Background
To assess the awareness and attitudes of parents towards respiratory syncytial virus (RSV) infection in the United States.

Methods
We developed an online, quantitative survey consisting of 34 questions, informed by a literature review, qualitative interviews, and cognitive tests. Between October 20th and November 25th, 2023, individuals who were expecting a child or had children aged ≤2 years were recruited through panels.

Results
In total, 153 individuals were recruited, of which 73% were female and 57% had completed some schooling beyond high school. On average, they were 33.9 years old (standard deviation:7.2) and 78% had at least one child aged ≤2 years in their household, while 48% were expecting a child.
Most parents (88%) agreed that having their children immunized is a good way to protect them from diseases, and 84% agreed that they follow their healthcare provider’s recommendation for their children’s immunizations. However, 66% said they were concerned about serious side-effects of immunizations, and 54% question the value of some types of immunizations.
Level of knowledge about RSV varied among parents, with 35% reporting that they knew a lot about it, 39% that they were somewhat knowledgeable and 20% that they knew what it is but not much else. Very few (5%) had only heard of RSV but knew nothing more, and just 1% had never heard of RSV at all. Among parents who were aware of RSV (n=151), 63% were moderately or extremely concerned about RSV in children, with 33% extremely concerned. 34% of parents with children had at least one child who had ever been diagnosed with RSV, of which 60% visited urgent care or an emergency department and 46% were hospitalized.
About half of parents (46%) were aware of immunizations newly available for RSV. 90% strongly or moderately agreed that RSV prevention is important for children, and 78% would be eager to ask their physician about RSV immunization options.

Conclusion
Findings show that most parents in the US are concerned about RSV in children and almost all think that RSV prevention is important for children. While a majority follow their provider’s recommendation, they also expressed concerns related to immunizations.

Disclosures
Yoonyoung Choi, PhD, MS, RPh, Merck: Employee|Merck: Stocks/Bonds (Private Company) Bianca Chun, MPH, Merck Sharp & Dohme LCC, a subsidiary of Merck & Co., Inc., Rahway, NJ.: Employee Tanaz Petigara, PhD, Merck & Co., Inc.: Employee|Merck & Co., Inc.: Stocks/Bonds (Public Company)
P-611. Improving Rabies vaccination delivery and access: A Quality Improvement Project
Authors: Dutta Ankhi , Taylor Margaret , Foster Catherine , Holzmann-Pazgal Galit , James Megan , Morgera Valerie , Velasco Michelle , Oliver Holly 
Published: January 2025

Abstract

Background
Rabies remains a global public health concern.Barriers affecting rabies post exposure prophylaxis include lack of access to the rabies vaccine, coordination of care, and costs. Due to the challenges of vaccine access and coordination, most rabies vaccines are given in Emergency Centers (ECs). Barriers faced by patients in the EC include increased wait times, costs, and lack of appropriate referral or follow up coordination. We initiated a quality improvement project (QIP) to improve access to rabies vaccination and delivery of appropriate doses of the vaccine in the Infectious Diseases (ID) Clinic at our institution.
Rabies post exposure prophylaxis in infectious diseases clinic

Methods
Our outcome measure was to increase the total number of patient encounters for rabies vaccination in the ID Clinic across the 3 campuses at TCH by 25% in 3 months. Process measures were 1) Increase the number of referrals placed to ID by EC on first encounter by 25% in 3 months. 2) Increase the percentage of patients seen in ID clinic for all subsequent doses. Balance measure was collecting surveys to evaluate patient satisfaction with the vaccine process, including any perceived barriers. Our PDSA cycles included: 1) Education on the process to the EC providers at each campus, pharmacy, and nursing leads 2) Creating an Epic smart phrase to include the rabies vaccine schedule with appropriate dates, ID clinic phone numbers, and rabies vaccine education for families. 3) Providing small cards with the Epic smart phrase and ID referral reminder to attach to EC provider workstations at each campus. 4) Request for a standardized order set to be built in Epic to include orders for HRIG (as indicated), rabies vaccine, and referral to ID.

Results
Figure 1 represents the percentage of vaccine encounters seen in the ID clinic with interventions marked. We had excellent patient satisfaction scores in the ID clinic related to less wait times, easy access and costs. There was a significant cost differential between the EC and ID clinic.

Conclusion
Rabies Vaccine encounters increased from 16% to 61% between September 2023 through April 2024 across all three campuses of the hospital. Vaccines were provided with appropriate indications. Patient satisfaction was high with significant cost savings. There are currently ongoing PDSA cycles to improve access to rabies vaccine further.

Disclosures
All Authors: No reported disclosures
P-637. Infection Incidence and Trajectory of Immune Recovery in Children, Adolescents, and Young Adults After Chemotherapy for Acute Lymphoblastic Leukemia
Authors: Zalot Morgan , Chehab Leena , Rossoff Jenna , Hoogstra David , Karthikeyan Subhi , Newmark Monica , VanDuine Ryleigh , Readwin Mary Beth , Vella Laura A , Fisher Brian T 
Published: January 2025

Abstract

Background
Advances in chemotherapy for acute lymphoblastic leukemia (ALL) have improved survival rates, but survivors remain vulnerable to infection after completing chemotherapy. Data have shown increased infection risk for pediatric ALL survivors compared to healthy children, yet few studies have prospectively tracked infection rates alongside immune recovery. This study aims to quantify infection incidence and describe the trajectory of immune reconstitution in the year after ALL therapy completion.

Methods
Patients aged 3-30 completing ALL therapy at a pediatric center are being followed for the first year off-therapy. Total immunoglobulin-G (IgG) and antibody (Ab)-specific IgG levels for varicella, measles, and 23 pneumococcal serotypes are measured at 3, 6, and 12 months. Infection events are recorded monthly to calculate infection incidence per 1000 patient-days.

Results
To date, 21 patients have been followed for ≥ 6 months. Median age at ALL diagnosis was 7.3 years (IQR: 3.4-10.1). 67% of patients had ≥ 1 infections; 93% of those with infections had ≥ 2. The overall infection incidence rate was 6.1 per 1000 patient-days. Of 46 infections, upper respiratory illness (20, 43.5%) and gastroenteritis (6, 13%) were most common (Table 1). 17 of 21 patients had not received intravenous immunoglobulin replacement (IVIG) within 6 months of therapy completion; their mean total IgG was 859.6 mg/dL at 3 months and 918.2 mg/dL at 6 months (Table 2). All 17 received ≥ 1 pneumococcus, varicella, and/or measles vaccine before ALL diagnosis. None had evidence of pneumococcus or varicella Ab recovery at 6 months, regardless of pre-ALL partial or full vaccination status (Tables 2-3). 7/11 patients fully vaccinated and 3/6 partially vaccinated for measles before diagnosis had normal Ab indices at 6 months off-therapy (Table 4).

Conclusion
Infections were common during the first year off-therapy, with many experiencing multiple illnesses. Total IgG levels were reasonable at 3 and 6 months, but there was no recovery of varicella or pneumococcus Ab, and only a subset of patients retained measles Ab. Continued assessment until 12-month follow-up for all 85 enrolled patients is necessary but preliminary data suggest potential need for Ab-informed revaccination.

Disclosures
Brian T. Fisher, DO, MPH/MSCE, Allovir: Grant/Research Support|Astellas: Data Safety Monitoring Board|Merck: Grant/Research Support|Pfizer: Grant/Research Support
P-656. Investigating the Current Status and Exploring Issues for the Construction of Ventilator-Associated Pneumonia Surveillance
Authors: Kanai Osamu , Ito Takanori , Fujita Kohei , Tanizawa Kiminobu 
Published: January 2025

Abstract

Background
Ventilator-associated pneumonia (VAP) is a major infectious complication in invasive mechanical ventilation (IMV)-controlled patients. Because VAP adversely affects multiple outcomes, including risk of death, length of intensive care unit (ICU) stays, and length of hospital stay, appropriate preventive measures need to be constructed. To establish preventive measures for VAP in our hospital, we surveyed the occurrence of VAP and summarized the issues identified in the process.

Methods
Patients who received 48 hours or more of IMV at our hospital in 2023 were included in this study. We retrospectively studied the number of ventilator-associated conditions (VAC), infection-related ventilator-associated complications (IVAC), and probable/possible VAP (PVAP) events using the ventilator-associated events (VAE) algorithm from the Centers for Disease Control and Prevention National Healthcare Safety Network. We used the records of ventilator settings used by medical engineers (ME) for daily ventilator check-ups to screen for VAC events. Clinical findings, including the results of bacteriological tests of lower respiratory tract specimens, were investigated using electronic medical records.

Results
Of the 143 patients (157 IMV events) who underwent IMV during the study period, 102 (113 IMV events) were eligible patients. There were 23, 8, and 3 events of VAC, IVAC, and PVAP, respectively. The incidence of VAC, IVAC, and PVAP per 100 IMV events was 20.4, 7.1, and 2.7, respectively. The main causes of VAC events other than IVAC and PVAP were pulmonary edema in 4 events and septic shock in 3 events. During this study, screening for VAC events was readily available in the ME inspection records. In contrast, because of the overlap in ordering methods for culture of lower respiratory tract specimens under ventilatory management and self-discharged sputum, it became necessary to comprehensively review the electronic medical record of the patient in question for bacteriological testing.

Conclusion
In our VAP surveillance, the proportion of IVAC and PVAP events in VAC events was small. To ensure smooth VAP surveillance, the method of ordering bacteriological tests needs to be revised.

Disclosures
All Authors: No reported disclosures
P-657. Mycoplasma pneumoniae Pneumonia in Korean Children and Adolescents in 2023, Multicenter Study
Authors: Wook Yun Ki , Jeong Moon Hye , Kee Lee Joon , Lee Taekjin , Cho Youngmin , Kang Da Yun , Lee Hyunju , Choi Eun Hwa 
Published: January 2025

Abstract

Background
Mycoplasma pneumoniae (MP) is the leading cause of community-acquired pneumonia in the post-pneumococcal conjugate vaccine era, particularly in children. Following the COVID-19 pandemic, a resurgence of MP pneumonia has been observed. Thus, we aimed to investigate the clinical manifestations, macrolide resistance patterns, and therapeutic approaches related to the recent MP pneumonia epidemic.
Numbers and percentage of antibiotics and corticosteroid utilization in managing Mycoplasma pneumoniae pneumonia

Methods
This multicenter study, conducted in South Korea, enrolled children and adolescents diagnosed with MP pneumonia between September and December 2023, spanning outpatient clinics and hospitalized settings. Clinical data were retrospectively collected from 13 referring hospitals using standardized microbiological criteria, including a positive PCR result or a four-fold increase in serologic tests. Statistical analyses were then performed to evaluate demographic characteristics, treatment modalities, and clinical outcomes.
Treatment options for Mycoplasma pneumoniae pneumonia according to defervescence

Results
In total, 474 patients were enrolled, of whom 374 met the microbiological confirmation criteria. The median age of the patients was 7.7 (IQR, 5.4–9.6) years, and the hospitalization rate was 88.6%. Most patients experienced fever (98.9%), and lobular/lobar consolidation (59.1%) was the most common radiological finding. The macrolide resistance rate remained high at 87.0% but did not significantly influence the radiological findings or outcomes. Patients with consolidation showed a longer fever duration (median 8 vs. 7 days, P = 0.020) and higher hospitalization rates (92.3% vs. 83.0%, P = 0.008). Macrolides and steroids were used in 83.0% and 50.6%, respectively. A total of 82 (23.6%) participants were considered to have defervesced naturally in 5 (IQR 4-7) days. The total duration of fever was 7 (IQR 5-9) days in those who used only macrolides (n=68, 19.5%) and 8 (IQR 6-10) days in those who used macrolides with other treatments (tetracyclines, quinolones, or steroids; n=129, 37.1%). There was no difference in complications or readmission rates between the two groups.
Therapeutic Management and Clinical Response of Children and Adolescents with Mycoplasma pneumoniae Pneumonia

Conclusion
This study highlights the ongoing challenge of macrolide resistance in MP pneumonia and the need for tailored therapeutic approaches. Macrolides remain commonly prescribed despite high resistance; corticosteroids are often used concurrently.
Comparison of Clinical Characteristics, Management, and Outcome of Mycoplasma pneumoniae Infection According to Radiologic Findings

Disclosures
All Authors: No reported disclosures