Citations

Abstract Introduction This study investigated differences in opinions about neurodegenerative disorders (NDD) in countries with large populations and expanded access to healthcare. Methods A 5-point Likert scale survey assessed opinions of 30–59-year-olds, pertaining to their parents and NDD conditions. 100 surveys, translated into native languages, were acquired in eight developed countries. Positive (somewhat- or strongly-agree) vs. other responses, sex, and country were submitted to logistic regression and Chi-squared analyses. Results “It is important for me to know if my parent has a risk for developing a NDD condition in the future, even if nothing can be currently done to prevent or cure those diseases” had higher positive responses in Australia (92%) compared to Germany (74%) and the USA (78%). “I believe that knowing about my parent’s risk for developing a NDD condition will help me assist in the planning of their future” had higher number of positive responses in Australia (91%) versus Japan (70%), Germany (76%), Italy (80%) and UK (80%). “If my parent(s) was found to be at risk for a NDD condition, I would want to learn more about medications and adaptive therapies that could delay onset” was responded to more positively in Australia (92%), Canada (78%), France (87%), Germany (78%), Italy (88%), UK (88%), and USA (81%) versus Japan (60%). Conclusions Australians responded more positively to questions related to care of a parent with a NDD disorder. These findings suggest cultural differences that could influence education and support systems requirements for sleep medicine providers and NDD patients.

Abstract Background Pathogenic variants in the DMD gene are associated with Duchenne and Becker muscular dystrophy (DMD/BMD). Professional medical societies currently recommend DMD carrier screening for all patients who are pregnant or considering pregnancy. Such testing may identify intragenic duplications of DMD (i.e., involving one or more exons but fully contained with the gene) in patients without a personal or family history of DMD/BMD. These incidentally detected DMD intragenic duplications, however, pose significant challenges for variant interpretation. Pathogenicity of an intragenic duplication depends on its structural configuration. Tandem duplications may cause reading frame disruption and gene loss-of-function; conversely, non-tandem duplications may not disrupt gene function. Current carrier screening assays cannot determine the structural configuration of an intragenic duplication. The current guidelines (e.g., the ClinGen PVS1 decision tree) presume intragenic duplications are in tandem unless proven otherwise. If this presumption of tandem configuration is inaccurate, it may lead to overestimation of variant pathogenicity, potentially resulting in unnecessary invasive procedures (e.g., amniocentesis for prenatal diagnosis) and/or having other negative impacts with regards to prenatal decision-making. This study aims to evaluate the validity of this presumption for incidentally detected DMD intragenic duplications. Methods We performed high-coverage whole-genome long-read sequencing on the PromethION instrument (Oxford Nanopore Technologies) for 15 cases with previously identified DMD intragenic duplications. Among these cases, four had personal or family history of DMD/BMD, while 11 had no known history (i.e., incidentally detected). The structural configurations of the duplications were determined by an in-house bioinformatics tool and manual inspection of the alignment files. Results In all 4 cases with a known personal or family history of DMD/BMD, the DMD intragenic duplications were confirmed to be in tandem, aligning with expectations of their pathogenicity. Interestingly, among the 11 cases with incidentally detected DMD intragenic duplications, seven (64%) were found to involve interspersed duplications. In five of these seven interspersed duplication cases, the involved DMD exons were co-duplicated with distinct segments of the Xp arm located 0.5–30 Mb away, forming complex structural variants. In another case, the duplicated DMD exons have inserted into the Xq arm, about 90 Mb downstream of DMD. The final case involved the duplicated DMD exons inserted into a repetitive region most consistent with 9q12 (i.e., the 9qh region). Conclusions Our study reveals that while DMD intragenic duplications in patients with a personal or family history of DMD/BMD were consistently in tandem, a substantial 64% of incidentally detected DMD intragenic duplications were not in tandem. These findings have important implications for both clinicians and laboratorians. They challenge the presumption of tandem configuration for DMD intragenic duplications in individuals where the variants were identified incidentally, e.g., through carrier screening in those without a family history of DMD/BMD. In these cases, we recommend classifying the DMD intragenic duplications as variants of uncertain significance (VUS), unless there is evidence of tandem configuration.

Abstract Objectives Evaluation of differences in the intestinal microbiome and resistome among high-risk patients (i.e. intensive care, oncology, transplant recipients) who are and are not colonized with carbapenem-resistant Enterobacterales (CRE). Methods One hundred and twelve rectal swabs were obtained from 85 patients with known CRE colonization status and cohorted. Long-read metagenomic next-generation sequencing (mNGS) was performed on rectal swabs. Microbiome and resistome analysis were performed by assessing α-diversity, β-diversity, relative abundance assessment and linear discriminant analysis effect size (LEfSe), comparing patients colonized (CRE positive) and not colonized (CRE negative) with CRE. Longitudinal analysis of sequential swabs collected over multiple hospital encounters on a subset of patients was performed at the patient level. Results The microbiomes of cohorts were similar when comparing α- and β-diversity measures and relative abundance. LEfSe analysis identified Gram-negative pathobionts enriched among CRE-positive samples and Gram-positive taxa enriched among CRE-negative samples. α-Diversity of the resistome differed at class, gene and allele levels. Relative abundance and LEfSe analysis demonstrated enrichment of genes conferring β-lactam resistance among CRE-positive patients; LEfSe also demonstrated enrichment of antimicrobial resistance genes to multiple antimicrobial classes. At the patient level, fluctuations in the microbiome and resistome among longitudinally collected swabs were associated with antibiotic exposure. Conclusions Differences between the microbiomes of CRE-positive- and CRE-negative-colonized patients at the cohort level were relatively muted, whereas statistically significant differences were observed among their resistomes. In patients followed longitudinally, shifts in microbiome and resistome composition were dramatic in between encounters and antibiotic exposures.

BACKGROUND AND OBJECTIVES Recent changes in European diagnostic criteria allow for serologic diagnosis of celiac disease in children. Those guidelines have not been adopted in North America; hence, we aim to assess the positive predictive value (PPV) of tissue transglutaminase (tTG) immunoglobulin A (IgA) assays used in North America in identifying histologic findings of celiac disease. METHODS Multicenter retrospective cohort study of children (<18 years) with an elevated tTG IgA within 6 months of an esophagogastroduodenoscopy between January 2016 and December 2021. Biopsy-confirmed celiac disease was determined by the presence of intraepithelial lymphocytosis and villous atrophy. The primary outcomes were the PPV of an elevated tTG IgA and tTG IgA greater than or equal to 10 times the upper limit of normal (10× ULN). RESULTS Overall, 4019 children (63.3% female; 9% type 1 diabetes, 2% Down syndrome) were included. Histologic findings were consistent with celiac disease for 3321 children (PPV = 82.6% [95% CI, 81.4–83.8]). Among the 1739/4019 (43.2%) children with tTG IgA greater than or equal to 10× ULN, 1651 had biopsy-confirmed celiac disease (PPV10× = 94.9% [95% CI, 93.8–95.9]). Five percent (88/1739) of children did not have histologic findings of celiac disease, including 41/1739 (2%) with normal histology. Diagnostic accuracy of tTG IgA varied widely among assays used in North America (PPV range: 71.5%–88.8%; PPV10× range: 89.3%–97.3%). Assays performed worse in children with type 1 diabetes (PPV10× 89% [95% CI, 83.5–92.8]). CONCLUSIONS Elevated tTG IgA in isolation is insufficient to confidently diagnose celiac disease. As tTG assay performance varied widely, diagnostic confirmation by a specialist prior to dietary changes is essential.

Abstract Background Despite advances in diagnosis and management, the interstitial lung disease (ILD) lexicon is plagued by ambiguous and inconsistent terminology that complicates communication and impedes knowledge generation. The objective of this Fleischner Society Consensus Statement was to produce standardized terminology for ILD multidisciplinary diagnoses and major phenotypes. Methods Interviews with 10 experts were used to identify ILD clinical diagnoses and major phenotypes. The preferred terms for each entity and potential alternatives were identified, alongside the rationale for the preferred term. Entities with more than one potential term were the subject of an online modified Delphi survey posed to the 29 committee members, aiming to achieve consensus. Committee members rated their agreement with the initially preferred term—5 (strongly agree), 4 (agree), 3 (neutral/unsure), 2 (disagree), and 1 (strongly disagree)—with the option to provide additional comments. Median score ≥4 and interquartile range ≤1 were considered consensus agreement. Terms not reaching agreement were discussed by video conference, followed by an additional survey that incorporated feedback. Results From the 60 initial terms, there were two root terms that required upfront consensus before survey initiation (ILD and interstitial pneumonia) and another eight terms that had no alternative suggested by the committee or in the literature. Agreement was met by 47/50 terms (94%) in Round 1 of the survey. The three terms (6%) that did not reach agreement met agreement in Round 2. Conclusions This document provides standardized recommended terms for ILD multidisciplinary diagnoses and major phenotypes that will facilitate communication among clinicians, researchers, patients, and other stakeholders.

Abstract Background Loperamide is a µ-opioid receptor agonist that reduces intestinal peristalsis and is used to treat diarrhea. We previously described significant cross-reactivity of loperamide with 2 fentanyl immunoassays. Since then, new fentanyl immunoassays, including a CLIA-waived point-of-care device, have been approved for clinical use. Methods We evaluated new fentanyl immunoassays for cross-reactivity to loperamide and its major metabolites, N-desmethyl loperamide (dLop) and N-didesmethyl loperamide (ddLop). Previously characterized assays were tested for cross-reactivity to ddLop, which recently became commercially available. Loperamide, dLop, and ddLop were spiked in drug-free urine for analysis by 5 enzyme immunoassays run on automated chemistry analyzers and one lateral flow assay for the detection of fentanyl. Results Loperamide and its metabolites produced positive results in 3 fentanyl immunoassays. The Immunalysis HEIA was previously determined to be reactive to both loperamide and dLop, but it was not reactive to ddLop. The Immunalysis SEFRIA was reactive to loperamide, dLop, and ddLop at minimum concentrations of 14.7 mg/L, 13.1 mg/L, and 17.0 mg/L. The Thermo Fisher DRI was previously determined to be reactive to loperamide and dLop, and it was reactive to ddLop at a minimum concentration of 33.1 mg/L. The Abbott iCassette, ARK Fentanyl II, and Lin-Zhi LZI II fentanyl assays showed no cross-reactivity to loperamide or its metabolites. Conclusions The cross-reactivity of loperamide, dLop, and ddLop in several fentanyl immunoassays has the potential to cause false-positive results during urine drug screening.

6554 Background: SER-155 is an investigational, oral, live biotherapeutic product (LBP) comprised of 16 bacterial strains designed to decolonize gastrointestinal (GI) pathogens, improve epithelial barrier integrity, and modulate immune responses to prevent bloodstream infections (BSI). In the placebo-controlled cohort 2 of the phase 1b study, SER-155-001 (NCT04995653), SER-155 was generally well tolerated with a safety profile similar to placebo and the incidence of BSIs, a secondary endpoint, was significantly lower after treatment with SER-155 when compared to placebo. We report exploratory analyses of biomarkers of T cell expansion relevant for immune reconstitution after HCT. Methods: Participants were randomized 1:1 to receive 4 days of oral vancomycin (for microbiome conditioning) and 10 days of SER-155 or placebo/placebo administered pre-HCT (course 1) and post-neutrophil engraftment (course 2). Primary endpoints were safety and SER-155 strain engraftment (PK). Exploratory endpoints included plasma cytokine concentrations measured by ELISA and analysis of peripheral blood mononuclear cells (PBMCs) by flow cytometry. Results: Demographics were comparable across treatment arms. 34 of 45 randomized participants were treated and received allo-HCT (SER-155, 20; placebo, 14); 28 received course 2 (SER-155, 19; placebo, 9). SER-155 strain engraftment was observed in the peri-transplant period (median 11.5 strains after course 1) and post-HCT (median 11 strains after course 2 and HCT Day 100). Significant differences and trends in cytokines of systemic inflammation and immune homeostasis were observed relative to placebo prior to HCT Day 0 and post-HCT. On HCT Day 0, both arms had similar concentrations of IL7 and IL15 (Table 1). However, after course 2, and at HCT Day 100, significantly higher concentrations of IL7 were observed in the SER-155 arm relative to placebo (p=0.02, and p=0.003, respectively). In a preliminary analysis of PBMCs from a subset of participants, a high frequency of CD4+ T cells were observed in the SER-155 arm at the same timepoints. For homeostatic cytokine IL15, no significant differences were observed between arms. Conclusions: The significantly higher concentrations of IL7 with SER-155 treatment and observed frequency of CD4+ T cells support the potential role of the GI microbiome in promoting homeostatic expansion of peripheral T cells and immune reconstitution important for successful HCT. Clinical trial information: NCT04995653 . Median plasma IL7 and IL15 (pg/mL), SER-155 vs. placebo (generalized linear model). HCT Day or event SER-155 IL7 Placebo IL7 SER-155 IL15 Placebo IL15 D0 13.8 13.0 31.9 30.4 D7 15.1 14.6 50.9 62.6 D14 12.8 15.5 56.6 69.8 Post-neutrophil engraftment 13.4 9.0 16.3 15.4 Post-course 2 7.4* 3.9 6.2 9.1 D100 7.1** 3.5 6.2 6.2 *p<0.05, **p<0.01.

INTRODUCTION: Determine contemporary rates of early mucosal recovery in children with celiac disease (CeD). METHODS: Multicenter retrospective cohort study in Canada and the United States. Children diagnosed with CeD between 2016 and 2021 who underwent a follow-up biopsy within 15 months of diagnosis were included. RESULTS: Overall, 96 of 130 children (74%) had mucosal recovery, including 48% children (12/25) who were assessed within 3 months. Musculoskeletal symptoms at diagnosis were the only clinical characteristic associated with persistent enteropathy. DISCUSSION: While mucosal recovery can occur within months, more than a quarter of children with CeD had persistent enteropathy within 15 months of treatment.