Citations

Purpose of review The increasing recognition and diagnosis of autoimmune encephalitis (AE) and paraneoplastic neurological syndromes (PNS) is partly due to neural autoantibody testing and discovery. The past two decades witnessed an exponential growth in the number of identified neural antibodies. This review aims to summarize recent rare antibody discoveries in the context of central nervous system (CNS) autoimmunity and evaluate the ongoing debate about their utility. Recent findings In the last 5 years alone 15 novel neural autoantibody specificities were identified. These include rare neural antibody biomarkers of autoimmune encephalitis, cerebellar ataxia or other movement disorders, including multifocal presentations. Summary Although the clinical applications of these rare antibody discoveries may be limited by the low number of positive cases, they still provide important diagnostic, prognostic, and therapeutic insights.

AbstractIntroduction/AimsRhabdomyolysis is an etiologically heterogeneous, acute necrosis of myofibers characterized by transient marked creatine kinase (CK) elevation associated with myalgia, muscle edema, and/or weakness. The study aimed to determine the role of electrodiagnostic (EDX) testing relative to genetic testing and muscle biopsy in patients with unprovoked rhabdomyolysis in identifying an underlying myopathy.MethodsEDX database was reviewed to identify unprovoked rhabdomyolysis patients who underwent EDX testing between January 2012 and January 2022. Each patient's clinical profile, EDX findings, muscle pathology, laboratory, and genetic testing results were analyzed.ResultsOf 66 patients identified, 32 had myopathic electromyography (EMG). Muscle biopsy and genetic testing were performed in 41 and 37 patients, respectively. A definitive diagnosis was achieved in 15 patients (11 myopathic EMG and 4 nonmyopathic EMG; p = .04) based on abnormal muscle biopsy (4/11 patients) or genetic testing (12/12 patients, encompassing 5 patients with normal muscle biopsy and 3 patients with nonmyopathic EMG). These included seven metabolic and eight nonmetabolic myopathies (five muscular dystrophies and three ryanodine receptor 1 [RYR1]‐myopathies). Patients were more likely to have baseline weakness (p < .01), elevated baseline CK (p < .01), and nonmetabolic myopathies (p = .03) when myopathic EMG was identified.DiscussionMyopathic EMG occurred in approximately half of patients with unprovoked rhabdomyolysis, more likely in patients with weakness and elevated CK at baseline. Although patients with myopathic EMG were more likely to have nonmetabolic myopathies, nonmyopathic EMG did not exclude myopathy, and genetic testing was primarily helpful to identify an underlying myopathy. Genetic testing should likely be first‐tier diagnostic testing following unprovoked rhabdomyolysis.

BACKGROUND: Heart failure triggers a shift in myocardial metabolic substrate utilization, favoring the ketone body 3-hydroxybutyrate as energy source. We hypothesized that 14-day treatment with ketone ester (KE) would improve resting and exercise hemodynamics and exercise capacity in patients with heart failure with reduced ejection fraction. METHODS: In a randomized, double-blind cross-over study, nondiabetic patients with heart failure with reduced ejection fraction received 14-day KE and 14-day isocaloric non-KE comparator regimens of 4 daily doses separated by a 14-day washout period. After each treatment period, participants underwent right heart catheterization, echocardiography, and blood sampling at plasma trough levels and after dosing. Participants underwent an exercise hemodynamic assessment after a second dosing. The primary end point was resting cardiac output (CO). Secondary end points included resting and exercise pulmonary capillary wedge pressure and peak exercise CO and metabolic equivalents. RESULTS: We included 24 patients with heart failure with reduced ejection fraction (17 men; 65±9 years of age; all White). Resting CO at trough levels was higher after KE compared with isocaloric comparator (5.2±1.1 L/min versus 5.0±1.1 L/min; difference, 0.3 L/min [95% CI, 0.1–0.5), and pulmonary capillary wedge pressure was lower (8±3 mm Hg versus 11±3 mm Hg; difference, −2 mm Hg [95% CI, −4 to −1]). These changes were amplified after KE dosing. Across all exercise intensities, KE treatment was associated with lower mean exercise pulmonary capillary wedge pressure (−3 mm Hg [95% CI, −5 to −1] ) and higher mean CO (0.5 L/min [95% CI, 0.1–0.8]), significantly different at low to moderate steady-state exercise but not at peak. Metabolic equivalents remained similar between treatments. In exploratory analyses, KE treatment was associated with 18% lower NT-proBNP (N-terminal pro-B-type natriuretic peptide; difference, −98 ng/L [95% CI, −185 to −23]), higher left ventricular ejection fraction (37±5 versus 34±5%; P =0.01), and lower left atrial and ventricular volumes. CONCLUSIONS: KE treatment for 14 days was associated with higher CO at rest and lower filling pressures, cardiac volumes, and NT-proBNP levels compared with isocaloric comparator. These changes persisted during exercise and were achieved on top of optimal medical therapy. Sustained modulation of circulating ketone bodies is a potential treatment principle in patients with heart failure with reduced ejection fraction. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05161650.

Background Frailty is common in heart failure (HF) and is associated with death but not routinely captured clinically. Frailty is linked with inflammation and malnutrition, which can be assessed by a novel plasma multimarker score: the metabolic vulnerability index (MVX). We sought to evaluate the associations between frailty and MVX and their prognostic impact. Methods and Results In an HF community cohort (2003–2012), we measured frailty as a proportion of deficits present out of 32 physical limitations and comorbidities, MVX by nuclear magnetic resonance spectroscopy, and collected extensive longitudinal clinical data. Patients were categorized by frailty score (≤0.14, >0.14 and ≤0.27, >0.27) and MVX score (≤50, >50 and ≤60, >60 and ≤70, >70). Cox models estimated associations of frailty and MVX with death, adjusted for Meta‐Analysis Global Group in Chronic Heart Failure (MAGGIC) score and NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide). Uno's C‐statistic measured the incremental value of MVX beyond frailty and clinical factors. Weibull's accelerated failure time regression assessed whether MVX mediated the association between frailty and death. We studied 985 patients (median age, 77; 48% women). Frailty and MVX were weakly correlated (Spearman's ρ=0.21). The highest frailty group experienced an increased rate of death, independent of MVX, MAGGIC score, and NT‐proBNP (hazard ratio, 3.3 [95% CI, 2.5–4.2]). Frailty improved Uno's c‐statistic beyond MAGGIC score and NT‐proBNP (0.69–0.73). MVX only mediated 3.3% and 4.5% of the association between high and medium frailty groups and death, respectively. Conclusions In this HF cohort, frailty and MVX are weakly correlated. Both independently contribute to stratifying the risk of death, suggesting that they capture distinct domains of vulnerability in HF.

Abstract Intratumoral heterogeneity poses a significant challenge to the diagnosis and treatment of glioblastoma (GBM). This heterogeneity is further exacerbated during GBM recurrence, as treatment-induced reactive changes produce additional intratumoral heterogeneity that is ambiguous to differentiate on clinical imaging. There is an urgent need to develop non-invasive approaches to map the heterogeneous landscape of histopathological alterations throughout the entire lesion for each patient. We propose to predictively fuse Magnetic Resonance Imaging (MRI) with the underlying intratumoral heterogeneity in recurrent GBM using machine learning (ML) by leveraging image-localized biopsies with their associated locoregional MRI features. To this end, we develop BioNet, a biologically-informed neural network model, to predict regional distributions of three tissue-specific gene modules: proliferating tumor, reactive/inflammatory cells, and infiltrated brain tissue. BioNet offers valuable insights into the integration of multiple implicit and qualitative biological domain knowledge, which are challenging to describe in mathematical formulations. BioNet performs significantly better than a range of existing methods on cross-validation and blind test datasets. Voxel-level prediction maps of the gene modules by BioNet help reveal intratumoral heterogeneity, which can improve surgical targeting of confirmatory biopsies and evaluation of neuro-oncological treatment effectiveness. The non-invasive nature of the approach can potentially facilitate regular monitoring of the gene modules over time, and making timely therapeutic adjustment. These results also highlight the emerging role of ML in precision medicine.

Abstract Background Metabolic syndrome (MetS), which can be induced or exacerbated by the current class of antipsychotic drugs, is highly prevalent in patients with schizophrenia and presents significant challenges to lifetime disease management. Supported by initial clinical results, trace amine‐associated receptor 1 (TAAR1) agonists have emerged as potential novel treatments for schizophrenia. Notably, non‐clinical studies have also shown weight‐lowering and glucoregulatory effects of TAAR1 agonists, including the investigational agent ulotaront. However, the translatability of these findings to humans has not been adequately assessed. Given that delayed gastric emptying (GE) was identified as a potential mechanism contributing to the metabolic benefits of TAAR1 agonists in rodents, the aim of this study was to evaluate the effect of ulotaront on GE in patients with schizophrenia and concurrent MetS with prediabetes. Methods Patients with schizophrenia were randomized to receive a single oral dose of ulotaront (150 mg) and their previous antipsychotic (PA) in an open‐label, crossover, two‐sequence design (NCT05402111). Eligible participants fulfilled at least three of five MetS criteria and had prediabetes defined by elevated glycated haemoglobin (5.7‐6.4%) and/or fasting homeostatic model assessment of insulin resistance (i.e. ≥2.22). Following an overnight fast and 4 h post‐dose, participants ingested a 99m Tc‐sulphur colloid radiolabelled egg meal (320 kcal, 30% fat). GE was measured by scintigraphy over 4 h. Endpoints included GE of solids half‐time (T 1/2 ) and percentage gastric retention at 1, 2 and 4 h. Results Thirty‐one adults were randomized and 27 completed the study. Ulotaront significantly delayed GE of solids [median GE T 1/2 ulotaront at 139 min (119, 182) vs. the participant's PA of 124 min (109, 132), p = .006]. A significant increase in gastric retention was seen in the ulotaront versus the PA group at 1 h (80% vs. 75%, p = .015), 2 h (61% vs. 50%, p = .023) and 4 h (17% vs. 7%, p = .002) post‐meal. Conclusion Ulotaront delayed the GE of solids in patients with schizophrenia and concurrent MetS with prediabetes. Additional studies are needed to assess whether treatment with TAAR1 agonists is associated with weight loss and glucoregulatory improvement.

Abstract Background Pivotal trials have shown that ustekinumab is effective in ulcerative colitis (UC). However, the population included in these trials do not represent the cohort of patients treated in the real world. In this study, we aimed to describe the effectiveness and safety of ustekinumab in a clinical cohort of patients with UC. Methods We performed a multicenter retrospective cohort study and included patients with active UC starting ustekinumab. Variables collected included demographics, clinical data, and disease activity (measured using partial Mayo score [PMS] and endoscopic Mayo score) at follow-up. The primary outcomes were cumulative rates of steroid-free clinical and biochemical remission (SFCBR), defined as a PMS &lt;2 while off steroids and a normal C-reactive protein and/or fecal calprotectin. Results A total of 245 patients met inclusion criteria. The median time of follow-up was 33 (interquartile range, 17-53) weeks, and 214 (87.3%) had previous exposure to a biologic and/or tofacitinib. Rates of SFCBR, clinical remission, and endoscopic remission at 6 and 12 months were 12.0% (n = 16 of 139), 29.0% (n = 71 of 175), and 18.0% (n = 7 of 39), and 23.8% (n = 15 of 63), 54.3% (n = 57 of 105), and 31.0% (n = 9 of 29), respectively. Non-Hispanic White race, higher baseline PMS, and the use of concomitant corticosteroids were independently associated with failure to achieve SFCBR. Of the 73 that were dose escalated, 28.4% did not respond, 49.3% experienced a benefit, and 21.6% achieved remission. Conclusions In a population enriched with refractory UC, ustekinumab was well tolerated and induced remission in a significant number of patients. Larger studies with a longer follow-up are warranted.