bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-2267. Autopsies: Revisiting the Gold Standard
Authors: Tsai Helen , Minamoto Grace Y , Burack Daniel A , Ramesh Rithva 
Published: January 2025

Abstract

Background
Infections in solid organ transplant (SOT) recipients continue to be a clinical challenge despite modern diagnostics. Autopsies have the potential to identify missed infectious diagnoses thereby informing the practice of transplant infectious diseases. We sought to evaluate the clinical value of autopsies by analyzing pre-and post-mortem infectious diagnoses of deceased SOT recipients.

Methods
We retrospectively reviewed deceased adult SOT recipients who underwent autopsies at our institution from January 2017 to December 2022. Electronic medical chart review of these recipients was conducted to determine the clinical infectious diagnoses during the hospitalization in which death occurred. Autopsy reports were reviewed for post-mortem pathological findings. Patients who expired near admission without clinical information or did not expire from infection were excluded. Two physicians independently reviewed clinical information and pathological data and applied the Modified Goldman Criteria to categorize clinical and autopsy infectious discrepancies.

Results
During the study period, 21 autopsies were performed (Table 1). Pre-mortem infectious diagnoses included bloodstream infections (n = 11), pneumonia alone including 1 case of Rhizopus and 1 case of Pneumocystis (n = 7), CMV viremia (n = 2), cholangitis (n = 1), and sepsis of undetermined etiology (n = 2). In no instances did an autopsy exam reveal an infection undiagnosed pre-mortem, and thus there were no diagnostic errors that met Modified Goldman Criteria. No specific histopathological staining was performed in the cases with CMV viremia or suspected Pneumocystis pneumonia. In the case of Rhizopus, no comment regarding evidence of angioinvasion or extent of infection was made in the autopsy report.

Conclusion
We did not identify any missed infectious diagnoses on post-mortem evaluation that would have impacted management or outcome. These findings emphasize the importance of collaboration between infectious disease specialists and anatomic pathologists to direct histopathologic and microbiologic testing on tissues of clinical interest. Accurate autopsy diagnoses for SOT recipients, who are at risk for opportunistic and emerging infections, can critically advance transplant medicine.

Disclosures
All Authors: No reported disclosures
P-2268. Candida tropicalis Invasive Infection in Febrile Neutropenia, a High Mortality Infection
Authors: Arango Marcos , Ramirez Isabel C 
Published: January 2025

Abstract

Background
Invasive candidiasis due to species other than Candida albicans emerges as a problem in neutropenic patients receiving antifungal prophylaxis, due to decreased susceptibility to triazoles. Candida tropicalis is the most frequently species in this population and is associated with higher mortality when compared to Candida albicans. The aim of this study is to characterize the neutropenic population with invasive candidiasis and establish differences in outcome of patients with Candida tropicalis infection compared to other Candida species.
Characteristics of patients with invasive candidiasis

Methods
Retrospective cohort study of patients with hematological malignancies undergoing chemotherapy who developed invasive candidiasis between 2010 and 2022. Comparison of two qualitative variables was performed using Pearson's Chi-square test or Fisher's exact test. Estimation of group survival was performed using the Kaplan-Meier method and comparison of survival functions with the Log-Rank test.
Results of multivariate analysis of risk factors associated with adverse outcomes.

Results
At the time of fungemia, 85% of patients had active malignancy, with a median of 14 days of neutropenia until the development of infection. 15% of patients had mucositis and up to 60% had concomitant diarrhea. 95% had previously received antibiotics and 87.5% had a central catheter. In 40% of the patients, the infection occurred as a breakthrough infection and in 37.5% it was associated with azole resistance. 32.5% of cases were associated with deep-seated infection and 25% had persistent fungemia. The 30-day mortality of patients with candidemia due to C. tropicalis was higher than that experienced by subjects with candidemia due to other species (69% vs. 35%, p = 0.034). The median overall survival was 15 days (95% CI 12-18) for the first group. Multivariate analysis showed that C. tropicalis infection was associated with an increased risk of all-cause mortality. The risk factors associated with cutaneous lesions were C. tropicalis infection and azul resistance.
Overall survival of study patients

Conclusion
Patients who develop C. tropicalis candidemia during febrile neutropenia after chemotherapy for hematologic malignancies have a higher mortality than those infected with other Candida species. Azole resistance emerges as a threat given routine prophylaxis in this population, so mitigation strategies are necessary.

Disclosures
All Authors: No reported disclosures
P-2269. Mixed Fungal Infection in Patients with Hematological Malignancies
Authors: Ramirez Isabel C 
Published: January 2025

Abstract

Background
Invasive fungal infection (IFI) is a complication of neutropenia related to hematological malignancy that carries high mortality. Invasive candidiasis remains the predominant cause of yeast infection, followed by molds, primarily Aspergillus, Fusarium, and Mucorales. The clinical spectrum varies, with fungemia and pulmonary IFI being the most common; however, sinusitis, sinopulmonary and disseminated diseases also occur or may have overlapping manifestations. Commensalism and opportunism between microorganisms can favor superinfection as has been previously demonstrated with bacteria and yeasts, virus and mold species, however, mixed fungal infections (MFI) of both yeast and molds are rarely found simultaneously.
Characteristics of patients with mixed fungal infection

Methods
Medical records and laboratory data of patients with hematological malignancies with IFI were retrospectively reviewed over a 10-year period at a tertiary care hospital. Fungal infection was diagnosed according to the EORTC/MSG criteria, and MFI were defined as the simultaneous isolation of different fungal species in the same or in different representative microbiological specimens.

Results
22 episodes of MFI were found. In 90% of cases it was associated with prolonged neutropenia, most patients had acute leukemias. The most common manifestations were pulmonary IFI and fungemia (10/22), followed by sino-pulmonary IFI and fungemia. Infection by yeast and molds occurred in 13/22 cases and by different species of molds in 9/22 cases. The most common MFI was aspergillosis associated with invasive candidiasis (7/22), followed by aspergillosis and fusariosis (3/22) and aspergillosis associated with Curvularia infection (3/22). Breakthrough infection occurred in 11 of 22 cases. Mortality was 50%, those who survived, all resolved neutropenia.

Conclusion
MFI are rare and often associated with high mortality, neutropenia resolution is an important factor for survival. Mold infection is usually manifested with sino-pulmonary involvement, so it is considered that it is caused by the same fungus. However, this study demonstrates that the etiology of sinusitis may be different from that of pulmonary involvement and, therefore, highlights the need to emphasize invasive diagnosis at each of the sites involved.

Disclosures
All Authors: No reported disclosures
P-2270. Spectrum of Invasive Mold Sinusitis in Adults with Hematological Malignancies
Authors: Ramirez Isabel C 
Published: January 2025

Abstract

Background
Invasive mold sinusitis (IMS) occurs exclusively in immunocompromised patients. In patients with hematologic malignancies, it is associated with mortality and may affect cancer-related survival by causing delay of the chemotherapy regimen.
Clinical characteristics of patients with IMS

Methods
The records of adult patients with hematologic malignancies and proven or probable IMS over a 10-year period at a tertiary care hospital in Medellin, Colombia were retrospectively reviewed. Clinical aspects and results were evaluated
Microbiological data of IMS

Results
We identified 24 episodes of IMS in 23 patients. In all cases manifested with nasal congestion, 27% of the episodes occurred in acute leukemias, 50% in refractory disease and 22.2% in medullary aplasia and hematopoietic stem cell transplantation; 16.6% manifested as a breakthrough infection. 21 episodes were related to neutropenia at the time of diagnosis. Aspergillus spp. was isolated in 12 (52.1%) episodes, Fusarium spp. in 6 (26%). Other etiologies were Curvularia spp., Hormographiella aspergillata, Tropicoporus tropicalis, Rhizomucor spp., Cladosporium and Lasiodiplodia spp. In 5 episodes there was fungal coinfection mainly with Aspergillus spp. In 26% of the cases the sinusitis was related to invasive pulmonary aspergillosis (IPA). The galactomannan antigen test was positive in patients with IPA and negative in cases of isolated sinusitis. All patients underwent surgical debridement and had positive histology and microbiological isolation with morphological and/or molecular identification. 13 episodes were treated with voriconazole and the response was defined as complete and partial in 10 and 8 of the episodes respectively. 7 patients died, 5 due to refractory hematological disease and one attributable to infection as it was rhinosinusal mucormycosis.

Conclusion
IMS is an expected complication of cytotoxic chemotherapy and is usually associated with profound and prolonged neutropenia. It is related to high mortality given the underlying malignant disease. Although Aspergillus spp. is the most common etiology, there are other molds that must be taken into account for better therapeutic guidance and therefore the need for invasive diagnosis is highlighted.

Disclosures
All Authors: No reported disclosures
P-2279. Breakthrough Invasive Fungal Infections in Patients with Acute Myeloid Leukemia on Anti-Fungal Prophylaxis (2022)
Authors: Nelson Julia M , Azim Ahmed Abdul , Bhowmick Tanaya , Majumdar Anjali , Bhatt Pinki , Schmidt Elizabeth , Hayman Jaclyn , Narayanan Navaneeth , Mohayya Sana M , Baireddy Moulika , Vemulapalli Bhargav 
Published: January 2025

Abstract

Background
Patients with hematologic malignancies, particularly Acute Myeloid Leukemia (AML), are at high risk for invasive fungal infection (IFI). Mold Active-Primary Antifungal Prophylaxis (MA-PAP) is recommended in these patients to prevent IFI, which carries high morbidity and mortality risk. Very few studies have compared rates of breakthrough IFIs (bIFIs) in AML patients treated with different MA-PAP regimens.

Methods
This is a single-center, retrospective cohort study of adults with AML aimed at determining the efficacy of MA-PAP and the incidence and characteristics of bIFIs. We reviewed the medical records of patients ≥ 18 years old with a diagnosis of AML admitted to Robert Wood Johnson University Hospital (RWJUH) in 2022 and received MA-PAP with either Micafungin (MYC), Voriconazole (VCZ), Posaconazole (PCZ), or Isavuconazole (ISA) for &gt; 7 days. bIFIs were classified as possible, probable or proven (based on the modified EORTC/MSG criteria) if they occurred after at least 7 days of MA-PAP initiation to within two weeks of discontinuation.

Results
A total of 87 patients were included. Twenty patients (24.1%) experienced a total of 22 bIFI events, with 2 considered proven, 5 probable, and 15 possible. The incidence of bIFI was 15.4% for MYC, 18% for VCZ, 28% for ISA, and 0% for PCZ. 59.1% of bIFIs were in patients that were neutropenic for &gt; 2 weeks at the time of bIFI. Proven bIFI were due to Candida Krusei and Mucormycosis. The mean length of hospital and ICU stay was the longest in the MYC group at 31 and 6 days respectively. Those who received VCZ experienced the highest number of reported adverse events (28, 41%) most often hepatotoxicity. Mortality was highest in PCZ (15.4%) followed by VCZ (11.5%).

Conclusion
Our institution experienced a high rate of bIFI, particularly among patients who received MA-PAP with VCZ or ISA. Prolonged neutropenia was an important risk factor for bIFI. Larger cohort studies are needed to accurately assess the risk factors and possibly mitigate the incidence of bIFI in this patient population on various MA-PAP. A comprehensive 10-year retrospective study is currently underway at RWJUH.

Disclosures
Pinki Bhatt, MD, Sanofi: Grant/Research Support Navaneeth Narayanan, PharmD, MPH, BCIDP, Astellas: Honoraria|Beckman Coulter: Honoraria|Merck: Grant/Research Support|Shionogi: Grant/Research Support
P-2280. Community-Acquired Pneumonia in Immunosuppressed Patients Admitted to the ICU
Authors: Viñán Garcés André Emilio , Sanabria-Herrera Natalia , Duque Sara , Garcia-Gallo Esteban , Guerrón-Gómez Gabriela , Reyes Luis Felipe F 
Published: January 2025

Abstract

Background
Severe community-acquired pneumonia (sCAP) remains a crucial infectious cause of global mortality, accounting for a significant proportion of ICU admissions. Immunosuppressed patients frequently develop sCAP; however, the clinical characteristics and clinical outcomes of patients admitted to the ICU due to sCAP are not clear. Here, we attempted to bridge this gap in the literature.
Figure 1
Isolated microorganisms in respiratory samples. A. General cohort; B. No immunosuppression risk factors group; C. Immunosuppression risk factors group

Methods
This secondary analysis of the prospective MIMIC-IV database included adults admitted to the ICU with CAP diagnosis. Patients were stratified based on the presence or absence of immunosuppression. Bivariate, multivariate, and survival analyses were conducted to identify factors associated with mortality within the immunosuppressed and their impact on hospital mortality.
Figure 2
Kaplan-Meier survival curve of 1-year after discharge survival probability stratified by immunosuppression status. Patients with and without immunosuppression are represented, the first group with 1 (blue) and the last with 0 (red).

Results
A total of 4742 patients were included, with 1502/4742 (32%) being immunocompromised. The mean age (SD) was 66 ±16.1years, with 2627/4742 (55.4%) males. A total of 1384 respiratory isolations were obtained with Staphylococcus aureus (43.2% vs. 40.6%; p= 0.45) and Pseudomonas aeruginosa (10.20 % vs 11.69 %; p= 0.39) as the most representative in both groups (Figure 1). Immunosuppressed patients presented both higher Charlson comorbidity index (7.12, SD 3.14 vs. 4.97, SD 2.59; p &lt; 0.01) and infection severity by the SAPS II score (39, [31-49] vs 37, [ 29-46]; p &lt; 0.01). Immunosuppression was associated with increased mortality rates (IH: OR 1.99 [95% CI: 1.63-2.43]; 6 M: OR 1.79 [95% CI 1.52-2.12]; 12 M: OR 1.93 [95% CI 1.64-2.28]; p &lt; 0.01) and both solid malignancy and infection severity were positively correlated with mortality (Table 1). Immunosuppressed patients had a lower survival rate even after adjusting for disease severity (Figure 2).
Table 1
Univariate and multivariate analysis of risk factors associated with in-hospital, 6-month, and 12-month deaths in the immunosuppressed population.

Conclusion
Immunosuppression was independently associated with mortality and lower survival in sCAP patients. An individualized patient risk approach is necessary as immunosuppression affects mortality differently than immunocompetent patients.

Disclosures
All Authors: No reported disclosures
P-2284. "Low Incidence of Bacterial and Viral Infection after Robotic Surgery Kidney Transplant"
Authors: Shah Nikita , DiStefano Nicholas , Morsi Mahmoud , Viotti Julia Bini , Simkins Jacques , Anjan Shweta , Guerra Giselle , Vianna Rodrigo , Natori Yoichiro 
Published: January 2025

Abstract

Background
Kidney and kidney-pancreas transplantation should benefit patients with end-stage kidney disease and diabetes mellitus. Immunosuppressive medication are required to prevent rejection and maintain graft. However, immunosuppression increases the risk of infection. Surgical procedures also lead to inflammation post-kidney transplant, which results in opportunistic viral/fungal infections. Robotic surgery is well established to be less invasive and cause less harm in the short term for patients. However, it has never been investigated for infectious disease complications post-kidney transplantation.

Methods
This was a single-center, retrospective cohort study conducted at a large kidney transplant center in the US. We included all recipients who had received kidney or kidney-pancreas transplants through robotic surgery between November 15th, 2022, and March 14th, 2023. We investigated the incidence of infection and its pathogen and the duration from transplant to infection for bacterial, fungal, and viral etiologies within 6 months post transplantation.

Results
Thirty-four, and 2 kidney and kidney/pancreas transplants were performed during the study period. Thirteen (36.1%) and 4 (11.1%) of urine culture positivity (predominantly Pseudomonas and E.coli) and bacteremia were identified. The causative pathogen of 4 bacteremia includes two Staphylococcus aureus, E.coli, and Morganella. Only 6/36 (16.7%) and 3/36 (8.3%) of clinically significant CMV and BK Polyomavirus DNAemia, which required treatment, including adjusting immunosuppression, were identified. Six cases of SARS-CoV-2 and one case of influenza were also identified.

Conclusion
We conducted a retrospective cohort study regarding infections after robotic kidney and kidney/pancreas transplant surgery. A very low surgical site infection and relatively low BK Polyoma viral infection rate were noted. Further study should be required to compare the incidence between robotic and traditional surgery.

Disclosures
Yoichiro Natori, MD, Eurofin/Viracor: Honoraria|Nobel Pharma: Advisor/Consultant
P-2287. Are Solid Organ Transplant or Hematopoietic Stem Cell Transplant Recipients at Greater Risks of Unfavorable Outcomes of Pneumocystis Pneumonia?
Authors: Winichakoon Poramed , Albasata Hanan , Poutanen Susan M , Hosseini-Moghaddam Seyed M 
Published: January 2025

Abstract

Background
Solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients with Pneumocystis pneumonia (PCP) appear to be at risks of adverse outcomes and mortality with limited data.

Methods
In this retrospective cohort, we compared the PCP manifestations, including clinical presentation, laboratory data, imaging studies, treatment and outcomes between SOT and HSCT recipients diagnosed with PCP at University Health Network, Toronto, Canada, from January 2011 to January 2022. We measured a composite outcome including 21-day ICU admission and/or 28-day all-cause mortality following PCP diagnosis. Using multivariable logistic regression analysis, we estimated adjusted odds ratio (aOR) to determine the concurrent effects of covariates.

Results
During the accrual period, a total of 32 (55.2%) HSCT (20 allogeneic, 11 autologous, and one cord-blood transplant recipients) and 26 (44.2%) SOT (10 kidney, 8 liver, 5 lung, and 3 heart recipients) fulfilled the PCP diagnosis criteria. Notably, chronic steroid treatment was more common in SOT than in HSCT recipients [24 (92.3%) vs 13 (40.6%), p = 0.001]. The median time of post-transplant PCP diagnosis was 488 days with interquartile range (IQR) 90-481 in the HSCT group, and 1,453 (IQR 38-3,909) days in the SOT group. In comparison, dyspnea [25 (96.2%) vs 23 (71.9%), p = 0.015], desaturation [16 (72.7%) vs 12 (38.7%), p = 0.015], and pleural effusion [8 (30.8%) vs 2 (6.3%), p = 0.014] were more frequent in the SOT group. We observed a higher fungal load [11,450 (IQR 2,207-191,750) vs 10,295 (IQR 2,405-21,325) copies/mL, p = 0.043] and occurrence of the composite outcomes [13 (50%) vs 3 (9.4%), p = 0.001) in the SOT than the HSCT group. In the multivariable analysis, SOT recipients (aOR 7.1, IQR 1.3-37.4), patients received chronic steroid treatment (aOR 1.3, IQR 0.2-6.6), required supplemental O2 at the initial presentation (aOR 1.8, IQR 0.3-10.4), and had pleural effusion (OR 10.4, IQR 1.5-70.8) were significantly at the risk of composite outcome.

Conclusion
SOT recipients appear to be at a greater risk of ICU admission and mortality than HSCT recipients. SOT or HSCT recipients with pleural effusion or requiring supplemental O2 on admission, particularly if receiving chronic steroid therapy, are particularly at risk of severe outcomes.

Disclosures
All Authors: No reported disclosures
P-2291. Low-level CMV Viremia After Solid Organ Transplant: Should We Treat?
Authors: Goyal Rohan , Burack Daniel A , Orner Erika , Tow Clara , Alsunaid Sammar R , Rochlani Yogita , Kyriazis Periklis , Bartash Rachel , McCort Margaret E 
Published: January 2025

Abstract

Background
Cytomegalovirus (CMV) disease is known to affect morbidity and mortality after solid organ transplant (SOT). However, less is known concerning low-level CMV viremia (llCMV) (&lt; 1000 IU/ml). Having llCMV and the decision to treat llCMV with antivirals may be associated with changes in long-term graft outcomes and mortality in SOT. We aimed to review patient-level outcomes of llCMV after SOT in our large urban academic medical center.

Methods
We performed a retrospective review of patients from Montefiore Medical Center who underwent heart, liver, lung, kidney, pancreas, or multi-visceral transplant between 2020-2021 and developed llCMV within 2 years of SOT. Chart review was performed to characterize how llCMV was managed and outcomes such as graft failure, graft rejection, rehospitalization, concomitant infections, and death relative to llCMV detection.Figure 1.Distribution of other infections affecting solid organ transplant recipients within 1 year of low level CMV viremia.

Results
Eighty-five adult SOT recipients who had CMV viral loads measured between 50 and 1000 IU/mL within two years of transplant were identified. See Table 1 for recipient details. The average time from transplant to llCMV was 272 days. Seventeen (20%) patients were receiving antiviral prophylaxis at the time of llCMV, while post-transplant CMV prophylaxis had been discontinued in 66 patients (78%) for an average of 149 days prior to llCMV. 64% (54/85) were started on antivirals or had an antiviral dose increase in response to llCMV, which was continued for an average of 109 days. Within a year of llCMV, 42 (49%) of SOT recipients were re-hospitalized. Forty-two (49%) of patients experienced non-CMV infections within 1 year of llCMV detection; see Figure 1. Graft rejection occurred in 25 (29%) of patients with llCMV, and 13 (15%) experienced graft failure. Mortality within 1 year of llCMV was 8% (7/85).

Conclusion
llCMV is likely a reflection of overall immune status and is often temporally associated with rehospitalization and concomitant infections. Graft rejection and death are uncommon in adult SOT recipients with llCMV within 2 years of transplant. Although antiviral use was common in response to llCMV, the benefit of this is unknown and comparison to outcomes of SOT recipients without llCMV or those not receiving therapy for llCMV is needed to better determine when treatment is needed.

Disclosures
All Authors: No reported disclosures