Citations

Abstract Background Spinocerebellar ataxia type 3 (SCA3), the most common autosomal dominant ataxia, is driven by the accumulation of polyglutamine‐expanded (polyQ) ATXN3 proteins. While promising as biomarkers, their longitudinal trajectories across multiple biofluids remain poorly defined. Objectives To quantify polyQ ATXN3 levels in cerebrospinal fluid (CSF), plasma, and urine within a comprehensive cohort, utilizing serial measurements to map protein dynamics. Methods We employed a validated immunoassay to quantify polyQ ATXN3 in 97 symptomatic and 13 presymptomatic SCA3 patients, correlating levels with clinical features, ancestry, disease status, and longitudinal progression. Results Asian participants exhibited lower plasma but elevated urinary polyQ ATXN3 levels relative to other ancestries. While CSF levels were higher in symptomatic patients at baseline, they showed a significant longitudinal decline. Conclusions PolyQ ATXN3 is a viable multi‐biofluid biomarker. Declining CSF levels likely reflect neurodegeneration, supporting its role in tracking progression and emphasizing the need for ancestry‐based adjustment in trials. © 2026 International Parkinson and Movement Disorder Society.

Abstract Background: The dynamic nature of surgical demand poses significant challenges in planning and scheduling resources to staff the surgical suite. Uncertainty in workload often leads to conservative upstream resource allocation, resulting in staffing misallocation. We propose a novel metric, the daily maximum number of open operating rooms (ORs), as an interpretable resource demand proxy to support staff planning. Methods: Using historical surgical data from Mayo Clinic in Rochester, Minnesota, from May 5, 2018 through October 8, 2023 (332,904 surgical cases), we developed a deep learning framework based on a wide-and-deep architecture to predict the daily maximum number of open ORs. The model incorporates features capturing historic OR use trends, seasonality effects, and anesthesia division–specific characteristics. Predictions are generated for forecast horizons of up to 90 business days. Results: Our results demonstrate strong predictive performance, with campus-level root mean square error values ranging from 5 to 7 available ORs across all forecast horizons. Validation across 9 anesthesia divisions confirms the frame- work’s capability to capture complex, nonlinear dependencies within longitudinal surgical datasets. Conclusions: This study introduces a novel operational metric and a robust predictive framework for perioperative resource management. By accurately fore- casting daily maximum open ORs, health care managers can better align staff capacity with anticipated demand, potentially enhancing staff use and improving the patient care experience by minimizing delays.

Abstract Importance Respiratory syncytial virus (RSV) hospitalization rates are highest among children <2 years of age. RSV immunization with infant monoclonal antibody or maternal vaccine is recommended to protect all U.S. infants in their first RSV season. For certain high-risk children aged 8−19 months entering their second RSV season, the monoclonal antibody nirsevimab is recommended. Little is known regarding preexisting health conditions as risk factors for RSV-associated respiratory failure in children during their second season. Objectives To describe children admitted to the pediatric intensive care unit (PICU) for RSV during their second RSV season by preexisting health conditions, and to compare demographic and clinical characteristics across groups. Design, Setting, and Participants Surveillance registry of children 8-<24 months old admitted to the PICU in 30 pediatric hospitals in the 2023-2024/2024-2025 RSV seasons. All children had an RSV-positive respiratory sample and received respiratory support with high flow nasal cannula, noninvasive ventilation, or invasive mechanical ventilation (IMV). Exposure Preexisting health conditions potentially increasing risk of severe RSV disease. Main Outcomes and Measures Patients were classified into four mutually exclusive groups by preexisting health conditions: 1) U.S. nirsevimab eligible criteria, 2) other identified RSV risk conditions (with some evidence of increased risk for severe RSV), 3) other preexisting conditions, and 4) no preexisting conditions. Patient demographic characteristics and level of respiratory support received were compared. Results Among 574 children: 47 (8.2%) had U.S. nirsevimab eligibility criteria, 76 (13.2%) had other RSV risk conditions, 96 (16.7%) had other preexisting conditions, and 355 (61.8%) had none. A higher proportion of children with nirsevimab eligibility factors (40.4%) than those with other identified RSV risk conditions (17.1%) required IMV, which was higher than other (10.4%) or no (5.9%) preexisting health conditions (p trend <0.001). Conclusions and Relevance Approximately 20% of children admitted to the PICU with severe RSV were in the defined groups that met U.S. nirsevimab-eligibility criteria or that had an identified RSV risk condition associated with known risk for severe RSV. A considerable proportion of both groups of children required IMV for respiratory support. These findings may help inform future deliberations regarding U.S. second season nirsevimab-eligibility recommendations. Key Points Question What preexisting health conditions are present in children aged 8–<24 months admitted to the pediatric intensive care unit for severe RSV disease in their second RSV season and how do clinical outcomes differ? Findings Among 574 children, 8% were eligible for nirsevimab in the U.S. and 13% had other preexisting conditions with known risk for severe RSV. Children with preexisting conditions, particularly those eligible for nirsevimab, were more likely to require invasive mechanical ventilation than those without. Meaning These findings may inform future deliberations regarding which children in their second RSV season might benefit from RSV preventive products.

Background: Patients with spina bifida are living longer and more productive lives; however, many continue to experience functional limitations in adulthood. This study evaluated long-term functional progression and ambulatory status using the combined Myelomeningocele Functional Classification (MMFC) and Functional Mobility Scale (FMS), and examined factors associated with long-term changes. Methods: A retrospective review at a tertiary care rehabilitation center identified 168 patients with spina bifida. MMFC and FMS classifications were recorded at initial and final visits. A subgroup of ambulatory patients who underwent 3D-gait analysis was analyzed to assess the relationship between MMFC, body mass index (BMI), and functional speed (FS) using multiple linear regression. Results: The average follow-up was 15±10.31 years. The mean age at final follow-up was 20 years (range, 5 to 52), with 52% of patients being male. Fifty-two percent of patients were ≥18 years of age at final follow-up. Within the MMFC1 cohort, 48% used wheelchair mobility (FMS 1,1,1) at initial presentation; this increased to 80% at final follow-up. Eighty percent of the MMFC2 patients were able to complete the 50-yard walk test at initial classification, whereas only 60% were able to complete it at final follow-up. Within the MMFC3 cohort, there was a decline in patients requiring no external support (FMS 6,6,6) from 90% to 78%. All MMFC4 patients maintained an FMS of 6,6,6. A statistically significant relationship was found between functional speed (FS) and MMFC (with MMFC4 faster than MMFC3 and MMFC2) ( P =0.01414). Conclusions: Long-term follow-up demonstrates that functional classification may decline over time in MMFC1 to 3 cohorts, whereas MMFC4 remains stable. In addition, within individual cohorts (MMFC1 to 3), there was also a decline in FMS and functional walk testing. A positive and statistically significant relationship was observed between gait analysis FS and MMFC, and a negative and statistically significant relationship was observed between BMI and MMFC. The combined use of MMFC and FMS provides a structured framework for longitudinal functional assessment in patients with spina bifida. Level of evidence: Level III.

Brexucabtagene-autoleucel (brexu-cel) produces high rates of measurable residual disease-negative (MRD-) complete response (CR) in adults with Philadelphia-chromosome positive (Ph+) acute lymphoblastic leukemia (ALL); however, subsequent relapses remain frequent. It is unclear whether maintenance with tyrosine kinase inhibitors (TKIs) can enhance remission durability. We evaluated outcomes among adults with relapsed/refractory Ph+ ALL who received commercial brexu-cel and achieved MRD- CR across 19 U.S. institutions. Considering TKI maintenance as a time-varying covariate, we analyzed outcomes based on receipt of subsequent TKI maintenance versus no maintenance. Patients receiving consolidative transplantation or non-TKI maintenance were excluded. Fifty-one patients were included: 20 received TKI maintenance and 31 received no maintenance. The use of TKI maintenance was associated with a significantly lower 1-year cumulative incidence of relapse (HR 0.12; 95% CI, 0.02-0.88; p=0.037) which translated into improved progression-free survival (PFS, HR 0.19; 95% CI, 0.04-0.85; p=0.029) and a trend towards improved overall survival (OS, HR 0.34; 95% CI, 0.07-1.62; p=0.18). There was no difference in non-relapse mortality (NRM, HR 0.83; 95% CI, 0.12-5.87; p=0.85). This real-world analysis supports the administration of TKI maintenance in Ph+ ALL following achievement of MRD- CR with brexu-cel as a strategy to improve PFS following chimeric antigen receptor T cell therapy.

Abstract Objective: Antibiotics are frequently prescribed for acute sinusitis despite national guidelines recommending antibiotics only if specific symptom criteria are met. We aimed to define the proportion of acute sinusitis encounters meeting criteria for antibiotic prescribing, characterize prescribing practices, and identify factors associated with guideline-discordant prescribing. Design: This retrospective cohort study included 1,000 randomly selected adult ambulatory encounters with a primary diagnosis of acute sinusitis between January 1, 2024 and March 31, 2024. Encounter notes were reviewed for appropriate antibiotic prescribing criteria as per national guidelines. Encounters were evaluated for drug selection and duration concordance based on local guidelines. A multivariable logistic regression analysis was performed to identify predictors of inappropriate antibiotic prescribing. Setting: Emergency departments, urgent care centers, and primary care clinics. Results: Antibiotic prescribing criteria were met for 67.6% of included encounters. Antibiotics were prescribed in 93.5% of encounters that met prescribing criteria, and 80.2% of encounters that did not. Both drug selection and duration were guideline-concordant in 49.2% of total encounters. On multivariable analysis, predictors of inappropriate antibiotic prescribing included cough (OR 2.15, 95% CI 1.08–4.29; P = 0.03) and symptom duration between 7 and 9 days (compared to <6 days; OR 7.70, 95% CI 3.24–18.31; P < 0.001). Electronic encounters were associated with lower odds of prescribing compared to in-person encounters (OR 0.03, 95% CI 0.01–0.09; P < 0.001). Conclusions: Most encounters for acute sinusitis result in an antibiotic prescription, despite prescribing criteria not being met. These findings may aid antimicrobial stewardship programs in benchmarking and optimizing antibiotic prescribing for acute sinusitis.

Abstract Early-phase clinical trials of BTK degraders in relapsed/refractory CLL have shown response rates of over 80%, including in patients with BTK mutations that confer resistance to conventional BTK inhibitors (BTKi). The molecular basis of resistance to BTK degraders is unknown and, given the promise of this class of drugs, would hold implications for therapy sequencing and the design of next-generation BTK degraders. To this end we identified five patients at Memorial Sloan Kettering who developed progressive disease while being treated on the phase 1 trials of zelebrudomide (NCT04830137, 4 patients) or bexobrutideg (NCT05131022, 1 patient). In two patients, one treated with zelebrudomide and the other with bexobrutideg, a pre-existing BTK A428D mutation had expanded at progression, rising from &lt;1.5% at the start of treatment to &gt;25%. In both cases, the increase in frequency of BTK A428D coincided with the loss of BTK degradation in peripheral blood B cells. No mutation in cereblon, the ligase utilized by these BTK degraders, was detected. To validate these clinical findings we generated wild-type and BTK A428D knock-in single-cell clones in TMD8 and HBL1 cells. BTK A428D conferred resistance to BTKi, including ibrutinib, acalabrutinib, zanubrutinib, and pirtobrutinib, as well as the clinical-stage BTK degraders zelebrudomide, bexobrutideg, BGB-16673, and AbbVie-1 (Compound 1, WO 2023183811). BTK A428D’s pan-resistance is unique compared to previously studied BTKi resistance mutations which remain susceptible to at least one BTKi and all clinical-stage BTK degraders tested. To understand how BTK A428D confers pan-resistance to BTKi and BTK degraders we conducted surface plasmon resonance studies which demonstrated that BTKi and all four clinical-stage BTK degraders tested are unable to bind BTK A428D. We next solved the crystal structure of apo BTK A428D to 1.8Å, which revealed that the mutant aspartate, which is larger and negatively charged compared to the wild-type alanine, sterically blocks BTKi and degraders from accessing residues in the hinge region of the kinase that are required for drug binding. We next asked why BTK A428D, despite conferring pan-resistance, has only been detected in 1.1% of patients treated with BTK inhibitors. Intriguingly, we noted that in one of our index patients, the frequency of BTK A428D declined and became undetectable after the withdrawal of zelebrudomide, suggesting a fitness defect. To assess this hypothesis, we compared the proliferation rates of five TMD8 wild-type and five BTK A428D single-cell clones; the BTK A428D clones grew more slowly and were consistently outcompeted in mixing studies. In summary, low-frequency BTK A428D mutations can expand under the selection pressure of BTK degraders and confer clinical resistance by preventing drug binding. The mutation, however, is outcompeted in the absence of BTK-targeted therapies. These findings provide rationale for the investigation of combination therapies and the development of next-generation BTK degraders capable of circumventing BTK A428D. Citation Format: Quinlan Sievers, Hao Lu, Allison Cool, Stefan Grajewski, Tim Kong, Mark Noviski, Xiaoli Mi, Emel Ficici, Ratul Mukerji, James Iuliano, Jordan Ye, Mateo Sanchez Garcia de los Rios, Hugo Bousquet, Sarah Whelan, May Tan, Christopher Phelps, Jahan Raman, Ryan Notti, Lizbeth Mendoza Navarrete, Samantha Sekeres, Eria Lamkin, Eduardo Bravo, Mark Ewalt, Prioty Islam, Anthony Mato, Lindsey Roeker, Justin Taylor, Meghan Thompson, Gwenn Hansen, Omar Abdel-Wahab. BTK A428D is a recurrent pan-resistance mutation to BTK degraders in clinical trials [abstract]. In: Proceedings of the Fifth AACR International Meeting on Advances in Malignant Lymphoma: From Discovery to Clinical Impact; 2026 Jun 24-27; Philadelphia, PA. Philadelphia (PA): AACR; Blood Cancer Discov 2026;7(3_Suppl):Abstract nr PR004.

Background: Self-expanding metal stents (SEMS) are recommended for the endoscopic palliation of distal malignant biliary obstruction (DMBO). Placement of SEMS during endoscopic retrograde cholangiopancreatography (ERCP) has been associated with an increased risk of post-ERCP pancreatitis (PEP). Objectives: The aim of this study is to evaluate rates of PEP in patients who underwent SEMS placement for pancreatic versus non-pancreatic malignancy. Design: Retrospective Cohort Study. Methods: Patients who underwent SEMS placement for DMBO between June 2017 and May 2021 were identified retrospectively from a procedural billing database. PEP incidence was compared between pancreatic and non-pancreatic DMBO groups and multivariate logistic regression was performed to identify risk factors for PEP. Results: A total of 488 individuals were identified, with 395 (80.9%) cases of DMBO due to pancreatic and 93 (19.1%) due to non-pancreatic malignancy. Stent types included 124 (25.4%) fully covered (FCSEMS) and 364 (74.6%) uncovered metal stents (UCSEMS). The overall rate of PEP in the cohort was 6.3% with no significant difference between pancreatic and non-pancreatic etiologies (6.1% vs 7.5%, p = 0.606). When adjusted for age <50 years old, female sex, and pancreatic stent placement, a non-pancreatic malignancy was not associated with an increased risk of PEP (OR 0.83, 95% CI 0.36–2.15). Conclusion: No statistically significant difference in PEP rates was seen after biliary sphincterotomy and SEMS placement for palliation of DMBO in patients with pancreatic versus non-pancreatic malignancies.