bluuebunny/crossref_metadata_2025 huggingface dataset:
P-689. Respiratory Syncytial Virus Infection in Patients with Cancer at Referral Oncologic Center in Mexico City
Authors: Salto-Quintana Jack N , Cardona Ortiz Alex , Martinez-Rivera Nancy , Becerril-Vargas Eduardo , Martin-Onräet Alexandra , Vilar-Compte Diana
Published: January 2025

Background

Respiratory Syncytial Virus (RSV) infection has a high risk of complications in patients with cancer. This study aimed to describe the clinical characteristics and outcomes of oncologic patients infected with RSV in a tertiary care hospital.

Methods

A retrospective study was conducted over ten years at the National Cancer Institute in Mexico City. Adults with a confirmed diagnosis of cancer and RSV by polymerase chain reaction (PCR) were included.

Results

Fifty-seven cases of RSV infection were included, 29 (50.9%) were women, the median age was 48 years (IQR 34-12), 15 (26.3%) were > 60 years; 36 (61%) had hematologic malignancies, and 23 (38.9%) solid tumors (two patients had both); 31 (54.4%) patients had active cancer; 24 (42.1%) received chemotherapy in the preceding 30 days. The most frequent comorbidities were hypertension (28.1%), obesity (17.5%), and diabetes (14%). Twenty-four (42.1%) patients had > 5 points on the Charlson comorbidity index. Fifty-seven percent of patients presented Systemic Inflammatory Response Syndrome.

Fifty-four percent were diagnosed during winter (December to February) (n=22). According to the immunodeficiency index for progression risk prediction in hematological patients with RSV disease, 13 (36.1%) patients were at high risk.

Seventy percent were hospitalized, although only 52.6% for pneumonia. Respiratory progression or deterioration was documented in 11 (19.3%) patients; 5 (8.8%) required mechanical ventilation, and 4 (7%) were admitted to the ICU.

Eleven (19.3%) patients were treated with ribavirin, with no outcome differences (P= NS). Co-infection was documented in 15 patients (26.3%): 4 (7%) had bacteremia, 2 (3.5%) had bacterial pneumonia, and 5 (8.7%) had other bacterial infections. Seven (12.2%) patients had viral co-infection: 4 (7%) with COVID-19, 2 (3.5%) with rhinovirus and one (1.7%) with influenza. The 30-day mortality was 14.8% (n=8/54).

Conclusion

In this cohort, morbidity and mortality were high. The therapeutic options for RSV infection are limited. Currently, there are effective preventive measures for some risk groups; however, they do not include oncologic patients. These data provide relevant information about the burden of disease in adults with cancer.

Disclosures

All Authors: No reported disclosures
P-693. RSV Pneumonia Incidence in Solid Organ Transplant Recipients from 2014 to 2023 in an US Collaborative Network
Authors: Contreras German , Golovko Georgy
Published: January 2025

Background

Few studies have assessed the burden of RSV disease in solid organ transplant recipients (SOTr). The aim of our study is to determine the cumulative incidence (CI) and outcomes of RSV pneumonia among SOTr over 10 years.

Cumulative Incidence of RSV Pneumonia in SOTr 2014-2023

Methods

We used the TriNetX platform to access aggregated and de-identified EHRs from healthcare organizations in the USA from January 1st of 2014 to December 31st of 2023. We included individuals ≥18 years old with history of Heart, Lung, Kidney, or Liver transplantation. RSV infection status was based on RSV laboratory testing and clinical diagnosis codes (CPT and ICD-10, respectively). The index event was defined as the day of the first positive RSV test. The primary outcomes of interest were ICU admission, Invasive Mechanical ventilation, and all-cause mortality 30-days after index event. We used the TriNetX built-in functions to perform analysis.

Results

A total of 34,301 SOTr recipients were tested for RSV and 1671 were positive for RSV infection.

The population was mainly Male (53%) and No Hispanic (87%) with a median age at the time of diagnosis of 56 years. A high proportion of the cases were diagnosed in the South (37%) and Midwest (24%).

The CI of RSV Pneumonia significantly increased from 2014 to 2023, and it was higher among Hispanic, individuals ≥ 64 years old and among heart transplant recipients (Figure A-B).

During the observation period 137 (8.2%) were admitted to ICU, 99 (5.9%) required mechanical ventilation and 455 (27.2%) had complications with the transplanted organ during the RSV episode and 42 (2.5%) died.

Conclusion

We found evidence of substantial ethnic and age inequalities in the incidence of RSV pneumonia in SOTr recipients.

Disclosures

All Authors: No reported disclosures
P-695. Analysis of Seasonal Influenza Activity in Los Angeles County throughout the COVID-19 Pandemic
Authors: Ransohoff Heidi , Traub Elizabeth , Maurice Annabelle de St
Published: January 2025

Background

COVID-19 pandemic restrictions impacted flu transmission, leading to lower incidence and high influenza activity outside of the typical respiratory season. Los Angeles County (LAC) Department of Public Health (DPH) typically defines flu season in LAC as the first week of October through the end of March. Because positive flu results became reportable in LAC via electronic laboratory reporting (ELR) in October 2019, this analysis uses this new data source to describe flu positive tests from the current and previous four flu seasons to understand how flu activity in LAC changed throughout the pandemic.

Methods

This analysis includes influenza positive test results for LAC residents reported to DPH via ELR with specimen collection dates from October 2019 to March 2024. Results were deduplicated at the specimen level. Descriptive statistics were used to analyze positive tests.

Results

During the 2023-24 flu season from October 2023 through March 2024, 39,412 positive influenza results were reported (87% flu A; 13% flu B), with the greatest number of positive results for flu A observed in December 2023 and flu B observed in February 2024. During the same months of previous seasons, the number of positive tests ranged from 217 tests in the 2020-21 season to 40,843 tests in the 2022-23 season. Peak months of flu activity ranged from November in the 2022-23 season to May in the 2021-22 season.

For all tests reported during the study period, subtyping was reported for 8% of positive flu A specimens. Lineage typing was reported for 0.04% of positive flu B specimens. During the current flu season, at least 1 positive test has been reported for flu A/H1, flu A/H3, and flu B/Victoria. The last recent positive flu B/Yamagata specimen was reported in January 2020.

Conclusion

Results show that flu activity in LAC during the current flu season appears to be returning to pre-COVID-19 pandemic seasonality; flu B activity peaked later in the season, which has been described for previous flu seasons. During the pandemic, peak months of flu activity varied from what is usually observed. No positive flu B/Yamagata tests since 2020 may support ongoing efforts to assess flu B/Yamagata extinction during the COVID-19 pandemic, prompting the World Health Organization to recommend excluding flu B/Yamagata from flu vaccines.

Disclosures

All Authors: No reported disclosures
P-699. The Impact of Low Influenza Immunization rates on U.S. Hospital System Resources. A Dynamic Model estimation
Authors: Nguyen Van , Mould-Quevedo Joaquin F
Published: January 2025

Background

Increasing influenza vaccination rates can significantly reduce the onset of severe symptoms and reduce the risk of complications. This helps alleviate the burden during flu seasons when hospitals may be overwhelmed with patients. Nevertheless, the overall vaccine uptake has been decreasing in the United States which is expected to have an important effect by increasing the burden of disease. The aim of this study was to estimate the impact of low influenza vaccination rates on disease burden and U.S. hospital system resources.

Methods

The impact of the reduced flu immunization rate was estimated using a dynamic age-stratified transmission model. Two U.S. flu seasons (2011-2012 for low incidence and 2017-2018 for high incidence) were used in the analysis to simulate the variation of flu epidemic. This study assessed four different flu vaccination rates: 25%, 30%, 35% and 40%. Outcome measures include number of infections, outpatient visits, hospitalizations, intense care unit (ICU) stays and deaths. The flu vaccine effectiveness (VE) rate was taken from CDC reports to estimate an average VE for all ages for the last 10 seasons (42%). Vaccination rates by age group were estimated using CDC reports and this model assumed immunization with quadrivalent flu vaccines for all ages. Total number of acute hospital and ICU hospital beds available for influenza were assumed in the U.S. at 300,000 and 30,000, respectively.

Results

Using U.S. flu immunization rate from season 2023-2024 (≈35%), in case of a high flu incidence season, the total number of symptomatic infections is expected to result in 71M, office visits in 29M, hospitalizations in 0.94M and deaths in 133,670. Any scenarios with an immunization rate below 45% will generate significant pressure on the US hospital system and would saturate the number of ICU hospital beds in high incidence seasons. Only increasing the flu immunization rate up to 50% or higher may prevent any saturation of acute hospital or ICU hospital beds regardless on the incidence of the flu season.

Conclusion

The U.S. analyses shows the critical need to increase the U.S. flu immunization rates to at least 50%, to improve health outcomes and avoid saturation of hospital system resources, especially those associated to ICU hospital beds.

Disclosures

Van Nguyen, PhD, CSL Seqirus USA: Advisor/Consultant Joaquin F. Mould-Quevedo, PhD, CSL Seqirus USA: Stocks/Bonds (Private Company)
P-710. Epidemiology of RSV infections in a birth cohort of healthy children, PREVAIL Cohort 2017-2020
Authors: Leon Maria Deza , Conrey Shannon C , Epperson Monica , Coughlin Melissa , Cline Allison R , Mattison Claire , Payne Daniel C , McMorrow Meredith L , Morrow Ardythe L , Thornburg Natalie J , Staat Mary A
Published: January 2025

Background

Acute bronchiolitis due to respiratory syncytial virus (RSV) is the leading cause of hospitalizations in infants in the United States. Most available data on RSV epidemiology were obtained from hospital cohorts or medically attended illnesses, focusing on symptomatic children. We examined the PREVAIL Cohort (2017–2020) of healthy, term infants in Cincinnati, Ohio to understand the epidemiology of RSV infections in a birth cohort under weekly surveillance.

Table 1

Medical attendance by age group, PREVAIL Cohort, Cincinnati, Ohio, 2017–2020

Methods

Children who were at least 70% adherent to the weekly sample protocol were included in this analysis. Weekly, mid-turbinate nasal swabs were tested using the Luminex Respiratory Pathogen Panel PCR test. Child serum samples were collected at birth, 6 weeks, and 6, 12, 18, and 24 months of age. Symptoms status and medical visits were obtained weekly via SMS text messaging. RSV detection was defined as a swab positive for RSV (A or B) or an increase in RSV pre-fusion log10 IgG ( >0.32) or IgA ( >0.20) F-antibody levels. Medical charts were reviewed for unreported medical visits. Asymptomatic infection was defined as no reported fever or cough onset within 7 days of the first PCR positive result.

Figure 1

Cumulative incidence of RSV detections by nasal swab and serology, PREVAIL Cohort, Cincinnati, Ohio, 2017–2020

Results

Overall, 137 infections were identified in 74/101 (73%) children: 66% (n=91) of infections were identified by PCR (48 (35%) RSV A, 43 (31%) RSV B) and 34% (n=46) were identified only by serology (subtype unknown). Two-year cumulative incidence was 65% by PCR only and increased to 73% when including serology; annual incidence was 0.71 infections/child year. Reinfections were common, with 48 (35%) second and 15 (11%) third infections by 2 years of age. Of the 91 PCR-identified infections, 24 (26%) were asymptomatic, 22 (24%) were symptomatic but not medically attended, and 45 (50%) were medically attended, of which 8 (18%) were hospitalized or seen in the emergency department. Seasonality of infection peaked between November and January, although infections were identified in the spring and summer months.

Seasonality of RSV infections throughout the study period (2017-2020) grouped by RSV subtype, PREVAIL Cohort, Cincinnati, Ohio

Conclusion

RSV infections were common in the PREVAIL cohort; most infections were symptomatic, but few were severe. Calculating RSV incidence using only medically attended cases of RSV underestimates disease burden and overestimates the proportion of severe cases.

Disclosures

Mary A. Staat, MD, MPH, Cepheid: Grant/Research Support|Merck: Grant/Research Support|Pfizer: Grant/Research Support|Up-To-Date: Honoraria
P-712. Effectiveness of Seasonal Influenza Vaccines against Medically Attended Influenza B, US Flu VE Network
Authors: Price Ashley , Chung Jessie R , Ellington Sascha , Flannery Brendan
Published: January 2025

Background

Quadrivalent influenza vaccines including both B/Victoria and B/Yamagata components were introduced during the 2013-2014 season in the United States. With the worldwide interruption of influenza B/Yamagata virus circulation since March of 2020, trivalent vaccines including a B/Victoria component are expected to be recommended for the 2024-2025 season. We describe quadrivalent vaccine effectiveness (VE) against medically attended influenza B from 2016-2017 through 2019-2020 when the majority of the seasonal influenza vaccinations were quadrivalent.

Methods

Study sites enrolled patients aged ≥6 months with acute respiratory illness and tested for influenza by RT-PCR. VE against influenza B was estimated using a test-negative design as 100% x (1 – adjusted odds ratio) comparing receipt of vaccination among B cases versus influenza-negative patients using logistic regression models adjusting for age, race/ethnicity, sex, calendar time and study site.

Results

Over 4 seasons, 34,994 patients were enrolled, including 2,849 influenza B cases (1,507 [53%] type B/Yamagata and 1,342 [47%] B/Victoria), 7,539 influenza A cases (3,048 [40%] H1N1 and 4,491 [60%] H3N2) and 24,607 patients without influenza. Among influenza B cases, ratios of B/Yamagata to B/Victoria varied by season; no B/Yamagata cases were confirmed after 2020. By season, quadrivalent vaccine effectiveness among patients of all ages ranged from 48% to 55% against B/Yamagata and 56% to 85% against B/Victoria. VE tended to be highest among children aged 6 months – 8-years and against B/Victoria associated illness.

Conclusion

Quadrivalent vaccines were effective against both lineages of influenza B viruses. Monitoring effectiveness of trivalent vaccines against B/Victoria and continued surveillance for emerging B lineages will be important.

Disclosures

All Authors: No reported disclosures
P-721. Risk Factors Associated with COVID-19 Among Fully Vaccinated Healthcare Workers in Lima, Peru
Authors: romero Candice , Ponce Diana , Soto Giselle , Marcenac Perrine , Leidman Eva , Mahon Garrett W , Fowlkes Ashley , Nayra Joan M
Published: January 2025

Background

Healthcare workers (HCWs) are an important target group for COVID-19 vaccination. In February 2021, Peru launched a COVID-19 vaccination campaign among HCWs using a BBIBP-CorV inactivated whole-virus vaccine (Sinopharm). We aim to understand risk factors for SARS-CoV-2 infection after vaccination using a cohort of HCWs in two hospitals in Lima, Peru.

Methods

Between August 2021-June 2022, HCW who received at least two COVID-19 Sinopharm vaccine doses were enrolled in the cohort and followed for 6 months. Participants provided a self-collected nasal swab weekly for SARS-CoV-2 by reverse transcriptase polymerase chain reaction testing. SARS-CoV-2 infection was confirmed by a positive PCR test result at least 14 days after receiving the second vaccine dose. Adjusted hazard ratios (aHR) were used to identify associations with infection accounting for potential confounding. Person-time was calculated based on days between negative PCR results, capped at 10 days; in cases of infection, the time between positive and negative tests was halved, with half the days considered at risk.

Results

Of 670 vaccinated HCWs, 111 (16.6%) tested positive for SARS-CoV-2 during the follow-up period. In adjusted models, prior report of COVID-19 illness in the previous 12-months was associated with reduced risk of infection (aHR: 0.98 [95% CI:0.97‒0.99], p=0.026). Being beyond 6 months since the last vaccination was significantly associated with an increased risk of infection (aHR: 3.22 [95% CI:1.66‒6.23], p=0.0001) as well as working in an outpatient setting (aHR: 1.94 [95% CI:1.06‒3.53], p=0.031).

Conclusion

In this cohort of healthcare workers undergoing regular asymptomatic COVID testing, our findings suggest evidence of waning protection at 6 months post-vaccination BBIBP- CorV. Additionally, preliminary indications suggest that healthcare worker behaviors or specific occupational exposures may contribute to increased infection risk even following vaccination. In addition, these results support the inclusion of HCWs as a priority group for additional booster doses of COVID-19 vaccine at 6 months after the most recent dose.

Disclosures

All Authors: No reported disclosures
P-750. The Use of Doxycycline for MRSA SSTIs in the Setting of Tetracycline Resistance (The DOXY-MASTER Study)
Authors: Nham Ashly , sikand harminder , Sullivan Eva
Published: January 2025

Background

Inducible doxycycline resistance has been reported in tetracycline (TET)-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolates. The two major resistance mechanisms found in MRSA involve efflux pump expression and ribosomal protection proteins (RPP), both of which are mediated by the presence of tet genes. In isolates that are positive for tetK and negative for tetM, in vitro studies have demonstrated an increase in the mean minimum inhibitory concentration (MIC) of doxycycline above the Clinical and Laboratory Standards Institute (CLSI) breakpoint for susceptibility after incubation in broth containing doxycycline. This study aims to investigate the presence of inducible resistance as defined by treatment failure with the use of doxycycline for MRSA skin and soft tissue infections (SSTIs) in the setting of tetracycline resistance.

Methods

This retrospective study analyzed patients from a 5-hospital health system and ensuing outpatient clinics from January 1, 2022 to February 29, 2024. Eligible patients were adults that had received doxycycline for the treatment of SSTI with a positive skin and soft tissue culture for MRSA that was susceptible to doxycycline. Exclusion criteria included presence of other organisms or concomitant infections requiring antimicrobial therapy, receipt of > 24 hours of effective systemic antimicrobial therapy against MRSA, and suspected or confirmed osteomyelitis or septic arthritis.

Results

A total of 164 patients were screened, and 35 patients met the inclusion criteria for analysis: 11 in the TET-resistant arm and 24 in the TET-susceptible arm. Any readmission occurred in 6 (54.5%) patients in the TET-resistant arm and 7 (29.2%) patients in the TET-susceptible arm. However, readmission for SSTIs occurred in 1 patient (9.1%) in the TET-resistant arm and 2 patients (8.3%) in the TET-susceptible arm (p >0.999) with an average of 39.3 and 20.3 days to readmission (p = 0.179), respectively.

Conclusion

In this small study sample, the use of doxycycline for MRSA SSTIs in the setting of tetracycline-resistance had no difference in treatment failure when compared to its use in tetracycline-susceptible isolates. This data suggests that susceptibility to doxycycline may be preserved in tetracycline-resistant MRSA isolates.

Disclosures

All Authors: No reported disclosures
P-751. A 10-year retrospective review of Necrotizing Fasciitis at a Tertiary Referral Hospital in a Low/Middle Income Country
Authors: Abdallah Tamara , Challita Caren , Zeid Daou Christopher Abi , Sawaya Tania , Hallal Ali , Madi Naji , Rizk Nesrine
Published: January 2025

Background

Necrotizing fasciitis (NF) is a rare, yet potentially fatal skin and soft tissue infection, with a global annual incidence of 0.3 to 15 per 100,000 cases. Early surgical debridement is crucial as mortality rates can reach up to 76%. there is a notable scarcity of data on the epidemiology of NF in the Eastern Mediterranean region. Our aim is to investigate clinical characteristics and outcomes among patients diagnosed with necrotizing fasciitis in a tertiary referral center in Beirut, Lebanon.

Demographic and Clinical Characteristics in the Study Population

Methods

A retrospective chart review of hospitalized cases between 2011 and 2021. The study population included adult patients diagnosed with NF during this period. Data included demographic and clinical characteristics.

Physical Findings

Results

We identified and included a total of 41 cases of NF in this cohort. The average age of the patients was 54.6 years, with males comprising the majority at 73%. The most prevalent co-morbidity was Diabetes Mellitus (48.78%), followed by hypertension (41.46%), cardiovascular diseases (41.46%), and renal failure (36.59%). Pain (87.80%), erythema (78.80%), and swelling (75.61%) were the most common symptoms. Skin discoloration was present in twenty-four of the forty-one patients (59%). Regarding outcomes, the patients identified were divided in two groups: survivors and deceased. overall mortality rate was 37%, and amputation rate was 10% (Table 3). Patients in both groups underwent a median of 3 surgical debridement’s. Time to diagnosis did not significantly differ between survivors (median 1.75 hours) and non-survivors (median 6 hours), whereas antibiotics were administered with a median time of 30 minutes from diagnosis in the survival group, compared to one hour in the deceased group. Time to surgery showed a 7-hour delay in the deceased group compared to survivors (p=0.096).

Timelines and Clinical Outcomes

Conclusion

To our knowledge, this study represents the first comprehensive review of necrotizing fasciitis (NF) in Lebanon, providing valuable insights into demographics and comorbidities. Our findings reveal a mortality rate of 37%, which is consistent with the ranges reported in existing literature, highlighting the need for continued efforts to improve outcomes for patients with NF in our region.

Disclosures

All Authors: No reported disclosures
P-753. Characterizing Multidrug-Resistant Acinetobacter baumannii Infections among Wartime Casualties
Authors: Frankford Stone A , Stewart Laveta , Sercy Erica , Igo Matthew , Wyatt Andrew , Carson M Leigh , Campbell Wesley , Mende Katrin , Tribble David , Kiley John L
Published: January 2025

Background

Acinetobacter baumannii (ACB) emerged as a key pathogen during the war in Iraq and was designated as a serious threat in the 2013 Centers for Disease Control’s antimicrobial resistance report. We describe the characteristics of wounded military personnel with ACB infections.

Methods

Data were obtained from the Trauma Infectious Disease Outcomes Study, an observational study of US service members injured in Iraq and Afghanistan (6/09-12/14). Patients who had ≥ 1 positive infecting ACB isolate were assessed. Multidrug resistance (MDR) was defined as resistance to ≥ 3 classes of antimicrobials or production of extended-spectrum β-lactamase or carbapenemase. Categorical variables were compared by Chi-square or Fisher’s Exact and continuous variables by Mann-Whitney U.

Results

Among 160 patients with ACB infections, 116 (73%) and 43 (27%) had MDR and non-MDR ACB, respectively. All were male with a median age of 23.5 years and the majority sustained injuries in combat (96%) in Afghanistan (93%) (Table 1). Blast was the primary injury mechanism (86%), resulting in high injury severity. There was a total of 283 ACB infections with 222 (78%) MDR and 61 (22%) non-MDR; 59 patients had ≥ 1 ACB infection (median of 2 [IQR 2-4] infections). Skin and soft-tissue infections (48%) were most common, followed by pneumonia (23%), bloodstream infections (15%), and osteomyelitis (11%) (Table 2). Compared to non-MDR ACB patients, patients with MDR ACB had greater transfusions requirements within 1st 24 hours post-injury (median 25 vs 15 units p=0.01, Table 1). There was a non-significant trend toward more abdominal/pelvic/groin injuries among MDR ACB patients (60% vs 42% with non-MDR p=0.051). Hospital duration was a median 52.5 days and crude mortality was 3% with no significant difference between the groups.

Conclusion

Battlefield casualties with ACB infections were characterized by high injury severity, frequently caused by blast trauma with MDR ACB more often in those with larger volume blood transfusions. Wound infections and pneumonia were most common. Overall, ACB infection patients were critically ill with large resource utilization regardless of MDR status. Further analysis to compare outcomes with non-ACB infection outcomes is warranted.

Disclosures

David Tribble, MD, DrPH, AstraZeneca: The IDCRP and HJF were funded to conduct an unrelated phase III COVID-19 monoclonal antibody immunoprophylaxis trial as part of US Govt COVID Response
P-754. Retrospective Study of Necrotizing Fasciitis: A Review of 99 Cases in a Tertiary Care Center in Eastern Thailand from 2022 to 2023
Authors: Lohawatcharagul Tuntanut , Jamjittrong Supaschin , Suenghataiphorn Thanathip , Kasemsantitham Arp-Arpa , Tangsirisatian Ponphisudti , Rojasavastera Sarita , Hongboontry Tinn , Kamonvarapitak Tunyaporn , Sasipong Nuttarak , Luerithiphong Sichon
Published: January 2025

Background

Necrotizing fasciitis (NF) is a rare and fatal soft tissue infection that requires immediate diagnosis and management. Data on microbiological aspects, clinical features, and outcomes of NF remain unexplored, particularly in certain global regions. With its high mortality rate, comprehensive understanding of NF is crucial.Figure 1.Inclusion Flow Diagram of Patients Diagnosed with Necrotizing Fasciitis between 2022-2023

Methods

All NF cases diagnosed at a tertiary care center in Eastern Thailand between January 2022 - December 2023 were retrospectively reviewed. Patient’s demographic, comorbidities, clinical presentations, laboratory data, treatment modalities, and clinical outcomes were evaluated.Table 1.Microbial Profile and Organism Distribution in Necrotizing Fasciitis Cases

Results

Among 99 NF cases identified, the mean age was 54.85 years (SD = 13.5), and 52.5% were males. Most common comorbidities were hypertension (48.5%), diabetes (44.4%), and dyslipidemia (38.4%). Wound cultures revealed 52.7% monomicrobial, 14% polymicrobial, and 33.3% no growth, with Streptococcus pyogenes being the most prevalent (28.6%). Average number of debridements per case was 3.06, and 53.5% of the patients underwent vacuum dressing with an average duration of 24.07 days (SD = 18.8). Significantly fewer patients underwent debridement within 24 hours if the initial diagnosis was cellulitis prior to being diagnosed with NF (21/43 (48%) versus 44/56 (78.5%), p = 0.002). The most common antibiotic regimen was ceftriaxone plus clindamycin (78.8%). Mortality occurred in 8 cases (8.08%), while 11 cases (11.1%) had amputations and 26 cases (26.3%) experienced severe sepsis.Table 2.Treatment Modalities and Their Attributes in Patients Diagnosed with Necrotizing Fasciitis

Conclusion

Our cohort exhibits a notably low mortality rate, compared to existing literature. Here, we present the first study exploring NF characteristics in Eastern Thailand. With findings indicating delayed debridement among patients initially diagnosed with cellulitis, this emphasizes the significance for prompt diagnosis of NF.Table 3.Clinical Outcomes in Study Cohort of 99 patients with Necrotizing Fasciitis

Disclosures

All Authors: No reported disclosures
P-758. A Comprehensive Analysis of Multi-Drug Resistant Tuberculosis: A Population-Based Time-Trend Analysis
Authors: Husain Ahmed , Alsakarneh Saqr , Malkawi Lujain , Alghizzawi Mohd , Brychel Christopher
Published: January 2025

Background

Due to the significant morbidity and mortality that it carries, Multi-Drug resistant Tuberculosis (MDR-TB) remains a pressing concern for public health. The aim of this study was to conduct a time-trend analysis of age and gender-specific MDR-TB incidence rates in the United States (US) using the Global Burden Diseases (GBD) 2019 database.

Methods

Data was obtained from the GBD 2019 database, an international database that encompasses ∼100% of TB diagnosed cases in the US. TB incidence rates, age-adjusted to the standard US population, were calculated using SEER*Stat software (v.8.4.0.1, National Cancer Institute “NCI”) and were additionally stratified according to sex. Time-trends were estimated as an Annual Percentage Change (APC) and Average APC (AAPC) using Joinpoint Regression Software (v.4.9.0.1, NCI) utilizing Monte Carlo permutation analysis to generate the simplest trend. Pairwise comparison was conducted between gender-specific trends using the tests of parallelism and coincidence. Age-specific trends were also assessed in two age sub-groups: younger adults 15-49 years of age and older adults 50-74 years of age. A two-sided P-value cut-off of 0.05 was utilized for statistical significance.

Results

6,820 patients were diagnosed with MDR TB in the US between 1990-2019. Overall, MDR-TB incidence rates have decreased in all study groups, with a more substantial decrease in older adults than younger adults (AAPC= -8.7 vs -6.6; AAPC difference=1.2, P< 0.0001). Age-specific trends were neither identical (P< 0.001) nor parallel (P< 0.001) (Figure 1), suggesting that MDR-TB incidence rates are different and decreasing at a greater rate in older adults compared to younger adults. Similarly, the incidence of MDR-TB has shown a greater reduction in females than males over the review time period (AAPC= -7.7 vs -6.6; AAPC difference= 1.1, P< 0.0001) (Figure 2).

Conclusion

Our nationwide study demonstrated that MDR-TB incidence trends have been decreasing in the United States over the past three decades, with a greater reduction noted in older adults and females.

Disclosures

All Authors: No reported disclosures
P-768. Gene Expression Profiles for Classifying Clinical Spectrum and Monitoring Treatment Responses in Tuberculoid and Lepromatous Leprosy
Authors: Mitra Debdeep
Published: January 2025

Background

Leprosy ranks as the second most prevalent mycobacterial disease worldwide. Various host genetic factors have been implicated in leprosy's sustained prevalence. Over the last decade, genetic epidemiology methodologies, such as genome-wide association studies (GWAS), have pinpointed over 30 loci associated with leprosy susceptibility. Nevertheless, GWAS loci typically encompass multiple genes, presenting a challenge in identifying causal candidates for each locus. Validating previously identified candidate biomarkers and discovering additional gene expression profiles are essential steps towards enhancing the diagnosis of Leprosy (Hansen's Disease) and monitoring treatment responses

Methods

The study involved assessing the expression levels of 126 immune-related genes in the skin biopsy samples of 96 individuals diagnosed with Leprosy, with a positive slit skin smear for acid-fast bacilli, and 20 healthy controls without Mycobacterium leprae. This evaluation was conducted using focused gene expression profiling via dual-color Reverse-Transcription Multiplex Ligation-dependent Probe Amplification assay. Additionally, gene expression levels were monitored twelve months post-Multi-Drug Therapy in 88 Leprosy patients as part of the follow-up assessment.

Results

Expression patterns of 31 host genes effectively distinguished between Pauci and multibacillary cases compared to both slit skin positive individuals and healthy controls at baseline. Notably, despite completion of multi-drug therapy at 12 months, the expression levels of most discriminating genes did not return to baseline (except for TLR10, BLK, CD38, SLAMF7, HS3ST2, and CD40LG mRNA), with full normalization observed only at the 24-month follow-up.

Conclusion

Our findings suggest that comprehensive gene expression signatures are necessary to assess transcriptomic responses in skin biopsies during and after successful multi-drug therapy for Hansen’s disease. This approach is crucial for accurate diagnosis and the characterization of drug-induced relapse-free cure. It involves integrating genes that normalize completely during the 12-month treatment phase with those that only fully return to baseline levels during the post-treatment resolution phase.

Disclosures

All Authors: No reported disclosures
P-779. Macronutrient Status and Risk of Tuberculosis vs. Other Lower Respiratory Tract Infections
Authors: Wu Joanne , Cegielski Peter
Published: January 2025

Background

Nutritional status is a major risk factor for incident tuberculosis disease (TB), but the underlying biological mechanisms remain unknown. If this effect is mediated immunologically, then other lower respiratory tract infections (LRTI) that elicit different immune responses would differ in this regard. If it is due to “body habitus,” then a similar association might be seen in anatomically similar infections. We compared the effect of nutritional status on TB, pneumococcal pneumonia (pneumonia), and influenza pneumonia (flu).

Methods

The first National Health and Nutrition Examination Survey (NHANES-I) provided data on baseline nutritional status of a probability sample of the US population, 1971-1975. Nutrition indicators included body mass index (BMI), skinfold thickness (SFT), cross-sectional upper arm muscle area (AMA), serum albumin, serum vitamin A, and iron status. The NHANES-I Epidemiological Follow-up Study provided follow-up data through 1992. Incident TB, pneumonia, and flu were ascertained through ICD9 codes in medical records and death certificates. For each nutrition indicator, we compared population-estimated percentages of those who later develop TB, pneumonia, and flu.

Results

An estimated 1.2% of the population developed TB: 9.6% (95% CI: 4.3, 15.0) of those with BMI < 18.5 kg/m2) developed TB compared with 1% (0.5, 1.4) of those with normal BMI, 18.5-25 kg/m2, and 0.4% (0.1, 0.6) of those with BMI 25-30 kg/m2 (Table 1). In contrast, BMI was not associated with developing pneumonia or flu. Like BMI, SFT and AMA were also inversely associated with incident TB but not with flu or pneumonia. In fact, pneumonia had an “U”-shaped association with AMA (Table 1). Among those with hypoalbuminemia (≤3.5 g/dL), 12.8% (0, 32.5) developed TB versus 0.8% (0.4, 1.2) of those with normal albumin >3.5 g/dL. Serum albumin was not associated with incident pneumonia or flu. Serum Vitamin A and iron deficiency were not associated with any of these three LRTI.

Conclusion

These differences suggest host defenses against TB, mainly adaptive cell-mediated immune responses, are sensitive to macronutrient status while the acute granulocytic and innate humoral defenses against other LRTI pathogens are not affected in the same way.

Disclosures

All Authors: No reported disclosures
P-782. Nontuberculous Mycobacterial Infections among Lung Transplant Recipients: A Nine-Year Cohort Study
Authors: Soneda Keiko , Yamamoto Shinya , Okamoto Koh , Higurashi Yoshimi , Ikeuchi Kazuhiko , Ikeda Mahoko , Okugawa Shu , Kawashima Mitsuaki , Konoeda Chihiro , Sato Masaaki , Tsutsumi Takeya
Published: January 2025

Background

The epidemiology, microbiology, and clinical course of nontuberculous mycobacterial (NTM) infection among lung transplant recipients vary considerably by geographic location. Their data is still scarce.

Methods

This single-center retrospective study was conducted at one of the major transplant centers in Japan. Medical records and microbiological test results of all the lung transplant recipients who underwent lung transplants between 2015 to 2023 were reviewed through December 31, 2023. Per institutional protocol, tracheal aspirates or sputum have been sent for mycobacterial cultures at the time of transplant and when clinically indicated thereafter. The definition of pulmonary NTM disease was based on the ATS/ERS/ESCMID/IDSA guidelines.

Results

In total, 175 lung transplants were performed during the study period (Table 1). Before transplant, 7 recipients had NTM isolation from the sputum and 5 of these 7 recipients had received bilateral lung transplants. While only 2 of these 7 recipients met the diagnosis of NTM pulmonary disease, 6 recipients received antimycobacterial treatment for a median duration of 25 months before transplant and only one case had NTM isolation after transplant (Figure 1). At the time of lung transplant, 169/175 (97%) recipient’s sputum were collected. Six species of NTM were isolated in 18 patients (10%, 18/175) at various times; at the time of transplant, between 0-1 month, 1-6 months, 6-12 months, and after 12 months in 2, 7, 3, 2, and 5 recipients, respectively (Figure 1, 2). Twenty-two isolates were recovered at the time of and after transplant, slowly growing mycobacteria accounted for 86% (19/22), including M. avium complex (N = 12) and M. gordonae (N = 4), whereas rapidly growing mycobacteria, M. fortuitum (N = 2) and M. chelonae (N = 1), accounted for the rest. Although 2 of 18 recipients with NTM isolation died, one recipient died directly from NTM infection complicated by Aspergillus coinfection.

Conclusion

NTM were isolated in 10% of recipients at the time of and after lung transplant. NTM, isolated before and at the time of transplant, rarely required treatment after transplant.

Disclosures

All Authors: No reported disclosures
Pulse Shape Discrimination in JSNS2
Authors: Dodo T , Cheoun M K , Choi J H , Choi J Y , Goh J , Haga K , Harada M , Hasegawa S , Hwang W , Iida T , Jang H I , Jang J S , Joo K K , Jung D E , Kang S K , Kasugai Y , Kawasaki T , Kim E J , Kim J Y , Kim S B , Kim W , Kinoshita H , Konno T , Lee D H , Lim I T , Little C , Marzec E , Maruyama T , Masuda S , Meigo S , Moon D H , Nakano T , Niiyama M , Nishikawa K , Pac M Y , Park H W , Park J S , Park R G , Peeters S J M , Rott C , Sakai K , Sakamoto S , Shima T , Shin C D , Spitz J , Suekane F , Sugaya Y , Suzuya K , Takeuchi Y , Yamaguchi Y , Yeh M , Yeo I S , Yoo C , Yu I
Published: January 2025

JSNS2 (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) is an experiment that is searching for sterile neutrinos via the observation of $\bar{\nu }_{\mu } \rightarrow \bar{\nu }_e$ appearance oscillations using neutrinos from muon decay-at-rest. For this search, rejecting cosmic-ray-induced neutron events by Pulse Shape Discrimination (PSD) is essential because the JSNS2 detector is located above ground, on the third floor of the building. We have achieved 94.95%$\pm$0.15% rejection of neutron events while keeping 92.82%$\pm$1.77% of signal, electron-like events using a data-driven likelihood method. This article will report the PSD technique using the full fiducial volume of the JSNS2 detector.
An unbreakable bond? Maternal adverse childhood experiences and mothers’ relationships with adult children
Authors: Stacey Lawrence , Reczek Rin , Williams Kristi , Hays Jake , Beth Thomeer Mieke
Published: January 2025

Adverse childhood experiences (ACEs)—the constellation of experiences of abuse, neglect, and household dysfunction in childhood—affect the subsequent formation and maintenance of social relationships. Yet to date, there is limited knowledge on the potential consequences of maternal ACEs for the mother–adult child tie, one of the most important relationships across the life course. Insights from a life course perspective and research on the deleterious effects of ACEs suggest that mothers’ experiences of ACEs in childhood are so powerful that they may shape mother–adult child relationship quality decades later. To test this possibility, we draw on nationally representative, longitudinal cohort data from the National Longitudinal Survey of Youth 1979 (NLSY79) and the NLSY79 Child and Young Adult Supplement to examine associations between maternal ACEs and mother–adult child estrangement, contact, and closeness. Multi-level logistic and ordinal logistic regression models show that greater maternal ACEs exposure is associated with greater odds of estrangement from, less frequent contact with, and lower levels of closeness to the mother as reported by the adult child. Our findings highlight and extend research on intergenerational relationships by demonstrating that a mother’s ACEs exposure may be a fundamental determinant of her relationships with her adult children, documenting lengthier intergenerational consequences of ACEs than uncovered by prior research.
A Serum- and Feeder-Free System to Generate CD4 and Regulatory T Cells from Human iPSCs
Authors: Fong Helen , Mendel Matthew , Jascur John , Najmi Laeya , Kim Ken , Lew Garrett , Garimalla Swetha , Schock Suruchi , Hu Jing , Villegas Andres Gordillo , Conway Anthony , Fontenot Jason D , Zompi Simona
Published: January 2025

iPSCs can serve as a renewable source of a consistent edited cell product, overcoming limitations of primary cells. While feeder-free generation of clinical grade iPSC-derived CD8 T cells has been achieved, differentiation of iPSC-derived CD4sp and regulatory T cells requires mouse stromal cells in an artificial thymic organoid. Here we report a serum- and feeder-free differentiation process suitable for large-scale production. Using an optimized concentration of PMA/Ionomycin, we generated iPSC-CD4sp T cells at high efficiency and converted them to Tregs using TGFβ and ATRA. Using genetic engineering, we demonstrated high, non-viral, targeted integration of an HLA-A2 CAR in iPSCs. iPSC-Tregs +/- HLA-A2-targeted CAR phenotypically, transcriptionally and functionally resemble primary Tregs and suppress T cell proliferation in vitro. Our work is the first to demonstrate an iPSC-based platform amenable to manufacturing CD4 T cells to complement iPSC-CD8 oncology products and functional iPSC-Tregs to deliver Treg cell therapies at scale.
Hyperbaric Oxygen Therapy (HBOT) for Management of Complex Regional Pain Syndrome (CRPS)
Authors: Cha Joon , Bosco Gerardo , Moon Richard E. , Melloni Giorgio , Camporesi Enrico M.
Published: January 2025

Objectives:

Complex regional pain syndrome remains a challenging condition characterized by severe, persistent pain and a variety of inflammatory and trophic symptoms. This study aimed to analyze the current literature to evaluate hyperbaric oxygen therapy (HBOT)’s efficacy in treating complex regional pain syndrome (CRPS), focusing on both sympathetically-maintained pain (SMP) and sympathetically-independent pain (SIP) subtypes.

Methods:

A comprehensive literature search was conducted in PubMed Clinical Queries using the MeSH term “Complex Regional Pain Syndromes” OR the keyword “CRPS” AND “Hyperbaric Oxygen Therapy” OR the keyword “HBOT”. The selected publication types included a randomized controlled trial, a retrospective observational study, a comparative study, a retrospective case series and case reports. The search was restricted to articles published in English between January 1994 and October 2024. The results from the search were used to compile this review. Patients were categorized into SMP, SIP, or indeterminate groups based on the presence of prior sympathetic nerve block history or disease duration.

Results:

Thirteen studies involving 280 subjects were reviewed. Of the patients, 42.5% were categorized as SMP, 48.2% as SIP, and 9.3% as indeterminate. HBOT treatment ranged from 3 to 63 sessions, typically using 2.4 ATA for 90 minutes. The results indicated significant symptom relief and functional improvement across both SMP and SIP subtypes, suggesting the broad efficacy of HBOT for CRPS management.

Discussion:

This review of the current literature suggests that HBOT may offer significant symptom relief, regardless of CRPS subtype or disease duration. HBOT’s anti-inflammatory and neuroplasticity promoting properties make it a valuable non-invasive option for CRPS patients, potentially improving outcomes when combined with other therapeutic modalities. Further research is necessary to refine patient selection and optimize treatment protocols.
Transfusion Practices in Traumatic Brain Injury: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Larcipretti Anna Laura Lima , Udoma-Udofa Ofonime Chantal , Gomes Fernando Cotrim , de Oliveira Jéssica Sales , Weba Elizabet Taylor Pimenta , Cavalcante Deivyd Vieira Silva , Dharaiya Madhav Kiritbhai , Bannach Matheus de Andrade
Published: January 2025

Objectives:

Balancing oxygen requirements, neurologic outcomes, and systemic complications from transfusions in traumatic brain injury (TBI) patients is challenging. This review compares liberal and restrictive transfusion strategies in TBI patients.

Data Sources:

Electronic databases were searched from inception to October 2024.

Study Selection:

We included randomized controlled trials comparing liberal and restrictive transfusion strategies in TBI patients.

Data Extraction:

Data were extracted by two reviewers using predefined forms.

Data Synthesis:

We included five studies with 1,533 patients: 769 (50.2%) in the liberal transfusion group and 764 (49.8%) in the restrictive group. There were no significant differences between groups favorable Glasgow Outcome Scale (risk ratio [RR], 1.16; 95% CI, 1.00–1.34), although a leave-one-out analysis demonstrated significance in this endpoint (RR, 1.24; 95% CI, 1.06–1.45). No significant difference was found regarding hospital mortality (RR, 0.98; 95% CI, 0.76–1.27), mortality at follow-up (RR, 1.03; 95% CI, 0.82–1.28), mortality in the ICU (RR, 1.00; 95% CI, 0.73–1.37), infection rates (RR, 1.08; 95% CI, 0.95–1.23), thromboembolic events (RR, 1.79; 95% CI, 0.74–4.31), hospital length of stay (LOS) (mean difference [MD], –1.45; 95% CI, –4.85 to 1.96), or ICU LOS (MD, –0.47; 95% CI, –3.84 to 2.91). The liberal transfusion strategy group had a significantly higher prevalence of acute respiratory distress syndrome (RR, 1.78; 95% CI, 1.06–2.98) and received more blood units per patient (MD, 2.62; 95% CI, 1.90–3.33).

Conclusions:

Our findings suggest that a liberal transfusion strategy results in better neurologic outcomes than a restrictive approach. Future research should examine the complication profile and the effects of using a 9 g/dL threshold. We advocate for revising current guidelines to establish 9 g/dL as the standard threshold for transfusions in TBI patients.