Citations

Background: We describe an investigation of a cluster of eight Corynebacterium amycolatum sternal surgical site infections (SSIs) that occurred among cardiac surgery patients from February to October 2025. Although C. amycolatum is a member of the skin microbiota, clinically significant infections caused by this organism may occur in cardiac surgery patients. Methods: The investigation included retrospective reviews of SSIs, clinical cultures and medical records, surgical observations, and operating room (OR) assessment. Line lists of surgical case criteria and infection prevention practices were created to assess common factors among cases (e.g., staffing, instrumentation, equipment, skin preparation and antisepsis, nasal decolonization, antibiotic protocols, and closure). Whole genome sequencing of isolates was performed and analyzed using SNIPPY for single-nucleotide polymorphism (SNP)-based phylogenetic analysis. Results: Phylogenetic analysis indicated isolates from five of eight case patients who had cardiac surgeries occurring over a six-week period from February to April 2025 were genetically related (?7 SNPs across the genome), suggesting a common source of infection. These five isolates were ceftriaxone, meropenem, and penicillin resistant. The other three case patient isolates were unrelated (<3181 to <15,000 SNPs); two were ceftriaxone, meropenem and penicillin resistant (one also doxycycline intermediate resistant), and the third penicillin resistant. Use of sternal tape for closure was identified as a recent practice change. Four of five genetically related cases involved the same surgeons and suture tape for sternal closure (wire for all other cases). Sternal tape was discontinued with three cases occurring afterwards. Seven patients completed chlorhexidine gluconate bathing and nasal decolonization. Hair was removed in the OR with reusable surgical clippers. All received the same skin antiseptic, and antibiotic prophylaxis was appropriate. No trends were identified in instrument or equipment use. Broad infection control measures were implemented, including surgical clipper replacement, OR cleaning and ultraviolet light disinfection, headlamp cleaning, and environmental repairs. Leadership was engaged through frequent meetings and audits. Infection control practices such as minimizing OR traffic, double gloving, glove changes, and strict adherence to hand hygiene and attire were reinforced. Two of eight cases occurred after these recommendations were completed but were not genetically related to the primary cluster. Conclusion: We describe a cluster of invasive C. amycolatum sternotomy SSIs. Only two genetically unrelated cases of C. amycolatum occurred following infection control investigation and interventions, underscoring the effectiveness of a comprehensive, multidisciplinary approach. This organism has rarely been reported as a cause of SSIs and may be an emerging pathogen.

Background: Measles is a highly transmissible virus. A single case can result in significant exposures within a healthcare facility and prompt action is needed to prevent secondary cases. In October 2025, Infection Prevention and Control (IPAC) was notified of a patient being admitted to our facility with recent international travel and symptoms consistent with measles. The patient was unvaccinated and had five healthcare facility visits prior to measles being suspected and subsequently confirmed. Objective: To describe our facility’s effective identification, prioritization, and prophylaxis of individuals exposed to measles. Methods: IPAC leveraged the electronic medical record to identify potentially exposed patients. Patients were quickly assessed for age and immune status, then prioritized and assigned to primary care teams. These teams promptly contacted patients and coordinated PEP administration. Results: Across five encounters, the index patient exposed 539 other patients. Due to delayed notification, our teams had less than four days to administer PEP for those exposed and still within PEP window. PEP administration began within hours of the index case’s positive test and patients received PEP within three days (Table 1). No secondary measles cases occurred within our facility. Conclusion: Timely and coordinated multidisciplinary effort enabled us to rapidly respond to our first measles case and control secondary transmission. Although the index case resulted in a large exposure, patients that were exposed and eligible for PEP were quickly prioritized to prevent secondary transmission.

Background: Advanced planning and adaptable response strategies are essential for preventing measles transmission in healthcare facilities. Objective: To describe a measles management plan and subsequent modifications in response to a cluster of measles cases. Methods: Drawing on previously published work (doi:10.1017/ice.2025.49), the Infection Prevention and Control (IPAC) team initiated a multi-disciplinary team and developed a measles preparedness plan with the following domains: Guidance and education; early detection and testing; isolation and patient movement; contact tracing and exposure management (Table 1). In October 2025, a patient was admitted during their fifth healthcare encounter and was diagnosed with measles. Two family members were later hospitalized with measles. Delayed recognition of the first case prompted enhancements to our preparedness framework (Table 1). Results: The first case resulted in 539 exposed patients. The second resulted in 87 exposures, and the third resulted in no exposure. Despite the extensive exposure, zero secondary measles were reported. Conclusion: Proactive planning enabled rapid response to our first case and controlled secondary transmission. Despite extensive planning, delayed identification of the first case caused significant exposures. As the cluster unfolded, we refined our plan, resulting in zero exposures from the last patient and zero secondary cases, despite over 850 exposures. These efforts may guide other healthcare facilities in improving their measles preparedness and response.

Background: Central line-associated bloodstream infections (CLABSIs) remain a challenge in pediatric intensive care units (PICUs); central line days have been directly correlated with risk of CLABSI. The Mayo Clinic PICU is a 23-bed multidisciplinary unit including dedicated bone marrow transplant beds with an average of 1048 admissions annually. In 2024, the unit’s CLABSI rate was 0.82 per 1,000 central line days or approximately 1–3 CLABSIs per year. Weekly multidisciplinary CLABSI Prevention Rounds were piloted from August 2024 to March 2025 with the aim of reducing central line device utilization rate as a method to reduce CLABSI risk. Methods: A multidisciplinary team of Clinical Nurse Specialists (CNS), Nurse Managers, and off-service PICU physicians conducted weekly CLABSI rounds on PICU beds (excluding 4 BMT beds), meeting with each bedside nurse as well as the on-service providers. The CLABSI team assessed central line necessity using a standard questionnaire and provided education to physicians and nurses regarding central line care and CLABSI prevention. Monthly data were compared for the same 8 calendar months pre versus post intervention for central line days, patient days, and device utilization rate (DUR; central line days/patient days), both unadjusted and adjusted for PRISM (Pediatric Risk of Mortality) 3 severity of illness score. Pre- and post-implementation staff surveys assessed confidence in line management and interdisciplinary communication using Likert scales. Results: Thirty-two CLABSI rounds with a total of 118 individual patients and 45 discrete interventions were noted over 8 months and compared to the 8 pre-intervention corresponding months. Pre versus post monthly DUR was 0.42 [0.32–0.57] vs 0.46 [0.30–0.55], p = 0.49 (PRISM 3–adjusted p = 0.97). Nursing confidence in ‘discussing central line need’ significantly improved post-implementation, 5 [4–5] vs 5 [5–5], p = 0.035. Nurses also positively perceived third-party involvement in need assessment, 4 [3–4] vs 4 [3–4], p = 0.06. All surveyed clinicians trended toward being less likely to think a central line was left in too long, 3 [3–4] vs 3 [2–4], p = 0.06. Conclusion: Structured weekly multidisciplinary CLABSI rounds are a feasible intervention that empowers bedside nurses and improves confidence in line maintenance and interdisciplinary communication. Median DUR was not significantly altered by the intervention, but nursing perception of central line management improved qualitatively in pre- versus post-implementation surveys. Continued expansion of multidisciplinary initiatives addressing central line necessity and management is needed to further evaluate overall effects on DUR and CLABSI incidence.

ABSTRACT Background Current staging systems for head and neck cutaneous squamous cell carcinoma (HNCSCC), such as AJCC8 and BWH, often fail to adequately stratify high‐risk patients, particularly due to the exclusion of important biological and host factors. This study aimed to identify independent prognostic factors for HNCSCC outcomes in the largest multi‐institutional retrospective series to date. Methods De‐identified data from 8,610 primary HNCSCC tumors, treated with curative intent surgery across multiple international centers, were analyzed. Outcomes included local recurrence (LR), locoregional metastasis (LM), distant metastasis (DM), and disease‐specific death (DSD). Multivariable Fine–Gray subdistribution hazard regression models with robust standard errors clustered at the patient level were fitted to generate exploratory hypotheses regarding independent hazard determinants. Results During a median follow‐up of 31.4 months (IQR 14.2–52.8), the cumulative incidence was 3.3% for LR, 2.7% for LM, 0.5% for DM, and 1.2% for DSD. Multivariable analysis confirmed that tumor diameter, poor differentiation, deep invasion, and large‐caliber perineural invasion (LCPNI) were the strongest predictors, being significantly associated with at least three of the four outcomes. Notably, factors currently excluded from or weighted differently in staging systems also proved critical: Immunosuppression was significantly associated with LR (SHR 2.03) and DSD (SHR 1.70); and lymphovascular invasion (LVI) was independently associated with LM (SHR 3.00). Poor differentiation demonstrated high prognostic impact, being a significant predictor for all four endpoints. Conclusion Tumor diameter, poor differentiation, deep invasion, LCPNI, immunosuppression status, and LVI are the most critical independent factors for HNCSCC prognosis. Our multi‐institutional data provide a robust framework for hypothesis generation, highlighting that incorporating host biological features and non‐anatomic variables could significantly refine future staging system discussions.

Abstract Background Glioblastoma (GB) exhibits marked tumor microenvironmental heterogeneity, contributing to both therapy resistance and poor survival outcomes. Intercellular adhesion molecule 1 (ICAM1) is an inflammation-associated adhesion molecule implicated in immune-stromal interactions, but its clinical and biological significance in GB remains incompletely defined. Methods We performed ICAM1 immunohistochemistry, bulk RNA sequencing, DNA methylation analysis, single-nucleus RNA sequencing, and preoperative MRI-derived morphologic feature analysis across multi-institutional cohorts of treatment-naïve IDH-wildtype GB. Results High ICAM1 expression at both transcript and protein levels is associated with shorter overall survival, particularly within the mesenchymal transcriptional subtype. ICAM1 expression is inversely associated with promoter methylation. Single-nucleus RNA-sequencing analysis shows that ICAM1-high tumors are enriched for mesenchymal, hypoxia, stress-associated, and immunosuppressive myeloid programs, suggesting that ICAM1 reflects a multicompartment inflammatory tumor ecosystem. ICAM1 expression, tumor surface irregularity, and patient age are independently prognostic and minimally correlated, capturing complementary clinical, imaging, and molecular features of GB biology. When combined, our Clinical-Imaging-Molecular (CIM) framework refines outcome prediction across independent GB cohorts using routinely available clinical data, conventional imaging, and standard immunohistochemistry. Conclusions ICAM1 characterizes an immune-remodeled, stress-adapted GB ecosystem associated with poor clinical outcomes. Integrating patient age, surface irregularity, and ICAM1 expression yields a scalable and clinically accessible prognostic framework for GB, supporting tailored outcome prediction, particularly in low- and middle-resource settings without routine access to advanced molecular profiling.

Abstract Background Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome comprising multiple pathophysiological phenotypes. HFpEF trials have largely enrolled diverse populations and reported average treatment effects, consistently yielding neutral results that may obscure drug-specific benefits within distinct subgroups. To address this issue, we employ an interaction-based that incorporates treatment-by-variable interactions to uncover drug-specific responses. Methods We leveraged four HFpEF clinical trials (TOPCAT, RELAX, NEAT-HFpEF, INDIE-HFpEF) and developed a framework comprising two complementary approaches. The first employed a prognostic responder model to evaluate whether conventional responder definitions reflect treatment-specific benefit or instead capture favorable clinical trajectories common to both treatment and placebo groups. The second used an interaction-based individual treatment effect (ITE) modeling to identify baseline variables that modify therapy effect, distinguishing drug-specific response from prognostic phenotypes. Results Although the prognostic responder model demonstrated good discrimination, further analisys suggested it primarily captured a prognostic signal associated with favorable clinical trajectories common to both treatment and placebo arms. In contrast, the ITE model identified distinct, drug-specific effect modifiers across trials (cardiorenal-inflammatory for spironolactone (TOPCAT), NO-mediated anti-inflammatory for isosorbide mononitrate (NEAT-HFpEF), afterload-reducing for inorganic nitrite (INDIE-HFpEF), and anti–volume-overload for sildenafil (RELAX). Each ITE model demonstrated significance only within its own trial suggesting drug-specific signal. Conclusions The proposed method identifies mechanism-specific effect modifiers, and uncovers clinically meaningful heterogeneity in treatment response, which is not captured by conventional MCID-based approaches. Although exploratory, these findings support phenotype-guided therapy in HFpEF and argue for phenotype-informed trial design to enhance treatment-effect detection and therapy targeting. Graphical Abstract

Abstract Genetic studies have significantly advanced our understanding of tauopathies, yet the genetic aetiology of Pick’s disease, a rare 3-Repeat tauopathy, remains unclear. The MAPT p.A152T variant has been identified as a risk factor for Alzheimer’s disease and progressive supranuclear palsy, but its role in Pick’s disease is unknown. In this study, we examined the prevalence of MAPT p.A152T in the largest series of neuropathologically confirmed Pick’s disease cases to date (n = 401). Through genotyping, we identified a single mutation carrier in the Pick’s disease cohort (minor allele frequency = 0.12%). We previously reported MAPT p.A152T at a 0.20% frequency in healthy controls (n = 2456), suggesting that it does not associate with 3-Repeat tauopathy risk. To further investigate the effect of the variant on MAPT transcript expression, we used bulk RNA sequencing in Alzheimer’s disease and progressive supranuclear palsy A152T mutation carriers. We did not detect significant differences in 4-Repeat tau levels, though preliminary trends may indicate more nuanced effects that need to be examined with long-read sequencing in a larger series. Overall, our study suggests that MAPT p.A152T does not increase Pick’s disease risk and may instead be linked to 4-Repeat or mixed tau pathologies, warranting further functional investigation.

Importance There is no consensus on staging and surveillance imaging for cutaneous squamous cell carcinoma (CSCC). Although imaging has been shown to affect management, broad recommendations from the National Comprehensive Cancer Network have led to variability in clinical practice. Objective To develop multidisciplinary consensus recommendations on the use of staging and surveillance imaging of localized CSCC. Evidence Review A multidisciplinary expert panel across academic and clinical practice settings convened a Delphi consensus, with 3 iterative survey rounds from January to June 2025. Data were analyzed from February 2025 to January 2026. Eligibility defined by at least 1 to 2 CSCC publications during the previous 5 years, involvement in a relevant clinical trial, experience treating at least 3 patients monthly with CSCC, and/or 5 years or longer of clinical practice. Fifty-four experts were invited and 45 (83%) completed all 3 rounds and were included in the final analysis. Structured Delphi surveys evaluated clinical scenarios, imaging modalities, and surveillance strategies for CSCC. Consensus and near-consensus recommendations were generated, defined as 80% or greater and 70% to 79% agreement, respectively. Findings The 45 participants (21 female individuals [47%] and 24 male individuals [53%]; 14 Asian individuals [31%], 1 multiracial individual [2%], and 30 White individuals [67%]) consisted of dermatology (15 [33%]), medical oncology (7 [16%]), radiation oncology (9 [20%]), radiology (9 [20%]), surgery (3 [7%]), and otolaryngology specialists (2 [4%]). The Delphi panel recommended staging and surveillance for CSCCs with at least a 15% risk of metastasis. Consensus or near consensus was reached to recommend staging and surveillance imaging for tumors with a concern for metastasis, bone invasion, invasion beyond subcutaneous fat, large-caliber nerve invasion, or a diameter of 4 cm or larger or the combination of tumors with poorly differentiated histology and any of the following: diameter of 2 cm or larger, lymphovascular invasion and subcutaneous fat invasion, or lymphovascular invasion and small-caliber perineural invasion. Computed tomography imaging was the preferred modality for nodal staging (38 [84%]) and surveillance (35 [78%]). For surveillance duration, consensus was reached to provide imaging for at least 2 years, and near consensus was reached for at least 3 years. Conclusions and Relevance This study provides an expert consensus–based framework to standardize imaging in localized CSCC that may inform future guidelines.