Citations

ABSTRACT The concentration of cells is a key component of modern blood tests. Given the biomarker potential of extracellular vesicles (EVs) in blood, we aimed to establish reference ranges for blood cell‐derived EVs using flow cytometry. To address the orders‐of‐magnitude variability in reported EV concentrations between different flow cytometers (FCMs), we first validated a calibration methodology to enable reproducible EV concentration measurements. The methodology was evaluated in an interlaboratory comparison study and shows that calibration reduces the median absolute deviation of EV concentrations measured on 25 different FCMs from 67 % to 25 %–31 %. The calibration methodology was then used to determine reference ranges of erythrocyte‐, leukocyte‐, and platelet‐derived EVs in human blood plasma in a cohort of healthy individuals ( n = 224). This study demonstrates that calibration enables comparable concentration measurements of blood cell‐derived EVs, thereby bringing EVs one step closer to clinical applications.

ABSTRACT Accurate identification of dysplasia in Barrett's esophagus (BE) remains a challenge. Advanced optical imaging techniques may allow for better localization of dysplasia in BE. Here, we have assessed the potential clinical utility of a previously described multimodal imaging probe combining optical coherence tomography (OCT) with angle‐resolved low coherence interferometry (a/LCI) to prospectively identify dysplasia in BE. Imaging was conducted on 37 patients undergoing endoscopic surveillance of BE, yielding co‐registered biopsies of 50 esophageal sites. The a/LCI nuclear morphology data were compared to a previous decision line to prospectively predict dysplasia, demonstrating 100% sensitivity, 93% specificity, and 94% overall accuracy. The NPV was 100%, comparable to previous a/LCI studies. The addition of OCT imaging markedly improved PPV and specificity, compared to previous studies with a/LCI alone, illustrating the clinical utility of the combined platform. These findings suggest that combining OCT and a/LCI enables better detection of dysplasia by providing better guidance.

Objective The purpose of this study was to determine the cumulative incidence of diagnosis switching, drug‐free remission, and initiation of a biologic or targeted synthetic disease‐modifying antirheumatic drug (b/tsDMARD) in individuals with seronegative rheumatoid arthritis (RA). Methods Adult residents of Olmsted County, Minnesota, with incident seronegative (rheumatoid factor negative/anti–cyclic citrullinated peptide antibody negative) RA meeting the 1987 and/or 2010 American College of Rheumatology classification criteria were included. Data were collected from January 1, 2005, to December 31, 2023, through manual chart review. Drug‐free remission was defined as a period of at least six months where the individual was no longer taking treatment for RA and did not have evidence of active inflammatory arthritis upon evaluation by a rheumatologist. We calculated the 10‐year cumulative incidence of a change in diagnosis, adjusting for the competing risk of death, and of drug‐free remission and initiation of a b/tsDMARD, adjusting for the competing risks of death or change in diagnosis. Results A total of 176 individuals with seronegative RA (68% women) were included. The 10‐year cumulative incidence of a change in diagnosis was 12.8% (95% confidence interval [CI] 8.7%–18.9%). The most common change in diagnosis was to spondyloarthritis (4%). The 10‐year cumulative incidence of drug‐free remission and initiation of a b/tsDMARD was 26.6% (95% CI 20.7%–34.2%) and 19.9% (95% CI 14.7%–26.9%), respectively. Over a median follow‐up of 11.8 years, 49 individuals entered drug‐free remission. Conclusion After initial diagnosis of seronegative RA, about 13% of individuals had a change in diagnosis and a quarter experienced drug‐free remission within 10 years.

PURPOSE Low-grade serous carcinoma (LGSOC) of the ovary, fallopian tube, or peritoneum is a hormonally driven, relatively chemoresistant malignancy with limited treatment options in the recurrent setting. Given frequent estrogen receptor (ER) expression and dysregulation of the cyclin-dependent kinases 4 and 6 (CDK4/6)–p16–Rb pathway, features shared with hormone receptor–positive breast cancer, dual endocrine, and CDK4/6 inhibition is a biologically rational strategy. This phase II trial evaluated ribociclib plus letrozole in recurrent LGSOC. METHODS This open-label, single-arm, multicenter phase II study enrolled women with measurable, recurrent LGSOC. Patients received ribociclib (600 mg orally, once daily, days 1-21 of a 28-day cycle) and letrozole (2.5 mg orally, once daily). The primary end point was investigator-assessed objective response rate (ORR) per RECIST 1.1. Secondary end points included clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS Of 74 patients screened, 51 were enrolled and 49 treated. The confirmed ORR was 30.6% (90% CI, 19.9 to 43.2), including one complete and 14 partial responses. Among responders, the median duration of response was 21.2 months. The CBR was 84% (90% CI, 72.5 to 91.6). The median PFS was 14.5 months (90% CI, 10.1 to 28.8), and the median OS was 44.5 months (90% CI, 31.8 to not reached). The most common grade ≥3 adverse event (AE) was neutropenia (47%), managed with dose modifications. Three grade 5 events (6%) occurred but were unrelated to treatment. Treatment discontinuation because of AEs occurred in 4%. No dose-limiting toxicities were observed. CONCLUSION Ribociclib plus letrozole met the primary end point, achieving meaningful response rates and durable disease control in recurrent LGSOC. The safety profile was consistent with prior CDK4/6 inhibitor studies. This combination represents a therapeutic option in this rare and genomically distinct subtype.

Background. Long-term outcomes in kidney transplantation remain suboptimal, with subclinical acute rejection (subAR) frequently going undetected by conventional methods. We hypothesized that subAR represents a molecular precursor to clinical acute rejection (cAR). Leveraging a large National Institutes of Health-funded cohort with matched kidney tissue and peripheral blood samples, our primary objective was to determine whether subAR and cAR share molecular patterns, establishing subAR as an early stage of cAR. As a secondary aim, we compared biopsy and blood gene expression profiles to identify unique and shared pathways and to assess their diagnostic utility. Methods. This was a retrospective analysis of gene expression data from an observational clinical trial. We analyzed 578 blood and biopsy samples from 129 kidney transplant recipients enrolled in a multicenter observational study. Gene expression differences were analyzed using ANOVA with false discovery rate correction and molecular pathways analysis. Samples were matched and classified based on histologic findings and blood-based molecular diagnostics. Results. Gene expression and pathway analyses revealed that subAR exhibits a molecular profile consistent with a milder form of clinical rejection in both tissue and blood. Molecular signatures distinguished immune-mediated injury from nonimmune injury. Notably, tissue gene expression profiling in cases that were misclassified by peripheral blood diagnostics were like correctly classified cases, suggesting that histology alone may not reliably define true clinical phenotypes. Conclusions. Molecular profiling of tissue and blood reflects distinct but complementary aspects of transplant biology and confirms that subAR and cAR share overlapping molecular profiles, supporting the hypothesis that subAR represents an early stage in the progression toward clinical rejection. These findings highlight the limitations of relying solely on histological evaluation and support the use of molecular tissue profiling as an adjunct to histology, particularly in diagnostically ambiguous cases. Molecular profiling provides a supporting framework for identifying subclinical rejection and guiding personalized immunosuppression to improve long-term outcomes.

Abstract Background These recommendations provide guidance on the optimal timing for transitioning from intravenous to oral antibiotics in patients with complicated urinary tract infection (cUTI), especially in presence of associated Gram-negative bacteremia. Methods The panel's recommendations are based upon evidence derived from systematic literature reviews which focused on comparative benefits and harms of transitioning to oral therapy versus continuing parenteral therapy of the total duration of treatment, including publications since 2000. These recommendations adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Results The guidelines panel suggests transitioning to oral antibiotics in patients with cUTI who are clinically improving, able to take medication, and for whom an effective oral option is available, rather than continuing parenteral therapy for the remaining treatment duration, regardless of the presence of associated Gram-negative bacteremia. An effective oral option needs to be active against the causative pathogen and achieve therapeutic levels in the urine and relevant tissue. Conclusions Parenteral and oral antibiotics used to complete treatment courses for cUTI provide similar efficacy and adverse events, especially in the context of shorter duration of therapy. This recommendation places a high value on reducing avoidable intravenous catheter-related adverse events, costs, and resources, as well as taking into account practical aspects of antibiotic administration.

Abstract Background These recommendations provide guidance on the optimal duration of antibiotics in patients with complicated urinary tract infection (cUTI), especially in presence of associated Gram-negative bacteremia. Methods The panel's recommendations are based upon evidence derived from systematic literature reviews which focused on comparative benefits and harms of shorter (5–7 days) vs prolonged (10–14 days) duration of antibiotics, including publications since 2000. These recommendations adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Results The guidelines panel suggests that patients with cUTI who are improving on effective therapy can be treated with shorter duration of antimicrobials (either 5–7 days of a fluoroquinolone or 7 days of a non-fluoroquinolone) rather than longer courses of antibiotics, regardless of the presence of associated Gram-negative bacteremia. An effective antimicrobial agent achieves therapeutic levels in the urine and relevant tissue and is active against the causative pathogen. However, men with febrile UTI in whom acute bacterial prostatitis is suspected may benefit from a longer treatment duration (10–14 days), and a short courses of oral beta lactams may require higher doses for efficacy. Conclusions Shorter durations of antibiotics for cUTI provide similar efficacy as longer courses, except in men with febrile UTI in whom acute bacterial prostatitis is suspected. This recommendation places a high value on antibiotic stewardship considerations as well as reducing the burden of antimicrobial administration from a healthcare perspective and reducing the burden of taking antibiotics from a patient perspective.

Abstract Background These recommendations address the empiric choice of antibiotics in suspected complicated urinary tract infection (cUTI). Issues to balance include the need for appropriate initial empiric antimicrobial therapy, the patient's severity of illness, and antimicrobial stewardship concerns. Methods The panel's recommendations are based upon evidence derived from systematic literature reviews that focused on comparative benefits and harms of classes of antibiotics approved for cUTI, starting with publications from 2008 onwards, and our review of predictors of resistance in uropathogens included references identified since 2000. These recommendations adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Results The guidelines panel suggests initially selecting among preferred empiric antibiotic choices rather than alternative options, stratified for the patient's severity of illness and antimicrobial stewardship considerations. When choosing among these antibiotics for a specific patient, the guideline panel suggests a 4-step process to account for changing resistance patterns and individualized patient needs. The steps are: (1) assess the severity of illness (for initial prioritization of antibiotics), (2) consider patient-specific risk factors for resistant uropathogens (for optimization of coverage), (3) evaluate other patient-specific considerations (to reduce the risk of adverse events), and (4) for patients with sepsis, consult a relevant local antibiogram if available (to further improve the likelihood of giving appropriate empiric therapy). Lastly, the guideline panel suggests selecting definitive effective therapy with a targeted spectrum based on the result of the urine culture. Conclusions Many of the classes of antibiotics approved to treat cUTI demonstrate similar efficacy as other classes of antibiotics in randomized controlled trials. Bacterial resistance prevalence is always changing, and new antibiotics will be developed. In this context, the guidelines panel provides recommendations for choosing empiric antibiotic therapy for cUTI that will help clinicians decide among available antibiotic options at the point of care.