Murray, Joseph A.

Abstract Background Crohn’s disease (CD) is a heterogenous, chronic inflammatory disorder driven by a combination of genetic, environmental, and microbiota-dependent risk factors. Mononuclear phagocytes (MNP) are crucial cells that maintain intestinal homeostasis. An important cytokine for MNP survival and function is granulocyte-macrophage colony stimulating factor (GM-CSF). Interestingly, several studies reported CD-associated genetic risk variants within the GM-CSF receptor and its downstream signaling components. Furthermore, high titers of autoantibodies specific to GM-CSF can be detected in CD patients. Taken together, this data suggests an important role for GM-CSF in abrogation of CD development in a subgroup of patients. Aims This study sought to investigate the function of GM-CSF autoantibodies in CD. Methods We retrospectively quantified and characterized GM-CSF autoantibodies in sera of 220 CD, 200 ulcerative colitis (UC) patients, and 220 healthy controls (HC) sampled at 3 time points prior to disease diagnosis and one time point after diagnosis. ELISA was used to determine GM-CSF autoantibody titers and isotypes followed by in vitro multiplexed mass cytometry (CyTOF) neutralization assays on peripheral blood mononuclear cells. Flow cytometry and CyTOF were used to map the profile of immune cells isolated from inflamed and non-inflamed CD mucosa. Results Our data demonstrates that GM-CSF autoantibodies are specific to CD, significantly elevated up to 7 years prior to diagnosis of disease, and correlate with disease location, severity, and complications at the time of diagnosis. Moreover, in contrast to GM-CSF autoantibodies in pulmonary alveolar proteinosis patients, CD-associated autoantibodies neutralize GM-CSF via specific recognition of post-translational modifications (PTM), affecting MNP function. Removal of PTM enabled GM-CSF to escape autoantibody binding and restored MNP response to GM-CSF in the presence of neutralizing antibodies, indicating a potential therapeutic avenue. Furthermore, we identified group 3 innate lymphoid cells (ILC3) as a major source of GM-CSF in the healthy intestinal tract, suggesting intriguing crosstalk of MNP and ILC3 across the GM-CSF-GM-CSFR axis. Conclusions Our results identify GM-CSF autoantibodies as predictive serological biomarker for CD in a subgroup of patients presenting with severe and complicated form of disease at the time of diagnosis. The presence of GM-CSF autoantibodies precedes the onset of CD by several years and likely abrogates homeostatic immune cell crosstalk involving ILC3 and MNP, suggesting the development of a pre-diseased state in CD patients. Funding Agencies CIHRDr. Edward Ketchum Graduate Scholarship

INTRODUCTION: Untreated symptomatic celiac disease (CD) adversely affects female reproduction; however, the effect of hidden CD autoimmunity is uncertain. METHODS: We identified women who were not previously diagnosed with CD and tested positive for tissue transglutaminase and endomysial antibodies between 2006 and 2011 in a community-based retrospective cohort study. We evaluated (i) the rate of adverse pregnancy outcomes and medical complications of pregnancy in successful singleton deliveries and (ii) reproductive characteristics in seropositive women without a clinical diagnosis of CD and age-matched seronegative women. RESULTS: Among 17,888 women whose serum samples were tested for CD autoimmunity, 215 seropositive and 415 seronegative women were included. We reviewed 231 and 509 live singleton deliveries of 117 seropositive and 250 seronegative mothers, respectively. Menarche and menopausal age, gravidity, parity, and age at first child were similar in seropositive and seronegative women. CD seropositivity was not associated with an increased risk of maternal pregnancy complications. Maternal seropositivity was associated with small for gestational age in boys (OR 3.77, 95% CI: 1.47–9.71; P = 0.006), but not in girls (OR 0.57, 95% CI: 0.15–2.17; P = 0.41). CD serum positivity was not associated with prematurity, small for gestational age (birth weight <10th percentile), or 5-minute Apgar score of less than 7. DISCUSSION: Although underpowered, the present study did not show any difference in reproductive characteristics or rates of adverse pregnancy outcomes in women with and without CD autoimmunity, except for birth weight in male offspring. Larger studies are needed to determine the effects of CD autoimmunity on female reproduction.

Abstract Esophageal lichen planus is an underrecognized condition, with fewer than 50 cases reported to date. Unlike cutaneous lichen planus, esophageal lichen planus occurs almost exclusively in middle-aged or older women who also have oral involvement. It commonly involves the proximal esophagus and manifests as progressive dysphagia and odynophagia. Endoscopic findings can include lacy white papules, pinpoint erosions, desquamation, pseudomembranes, and stenosis. Histologic features of esophageal lichen planus have only rarely been illustrated. They differ from those of cutaneous disease in several respects, including the presence of parakeratosis, epithelial atrophy, and lack of hypergranulosis. Correct diagnosis of esophageal lichen planus is difficult but bears important therapeutic implications. It is typically a chronic and relapsing condition that can require systemic or local immunosuppressive therapy and repeated endoscopic dilatations for esophageal strictures. Esophageal lichen planus may have malignant potential, as evidenced by 3 patients who developed squamous carcinoma of the esophagus after longstanding disease.

AbstractBackgroundOpioid‐induced esophageal dysfunction (OIED) is a recognized complication of chronic opioid use. However, the impact of acute opioid administration on esophageal motility remains unclear.MethodsOpioid naïve patients with high‐resolution manometry (HRM) <480 min following esophagogastroduodenoscopy (EGD) (opioid‐HRM) and a control group with HRM <36 h prior to EGD between January 1, 2016, and November 10, 2018, from a single institution were identified. EGDs were performed exclusively with versed and fentanyl.Key ResultsOne hundred and seventy‐four patients were identified, with 83 (47.7%) opioid‐HRM and 91 (52.3%) controls. Mean time from EGD to HRM was 229 (78–435) min. Baseline clinical features and HRM indications were similar between opioid‐HRM and controls. Chicago classification v3.0 defined HRM findings were similar between groups. Major motility disorders as defined by the Chicago classification v3.0 occurred at a similar frequency among opioid‐HRM and controls (27.7% vs. 36.3%, p = 0.23). Mean distal contractile integrity (DCI) was higher in opioid‐HRM (1939.3 ± 1318.9 vs. 1792.2 ± 2062.3 mmHg∙cm∙s, p = 0.043), but maximum DCI, distal latency, and integrated relaxation pressure did not differ between groups. Subgroup analysis assessing time and dose dependency did not identify differences in individual manometric parameters and Chicago classification v3.0 diagnosis between patients with HRM <240 min after EGD, >240 min after EGD, ≥125 mcg of IV fentanyl, <125 mcg IV fentanyl and controls.Conclusions and InferencesSame‐day acute opioid administration did not affect HRM findings in opioid naïve patients. Studies assessing the pathophysiology of and duration‐dependent relationship with opioids in OIED are needed.

Impaired AhR ligand production by the gut microbiota decreases AhR pathway activation, promoting inflammation in celiac disease.

The coronavirus disease 2019 (COVID-19) pandemic is associated with significant morbidity and mortality throughout the world, predominantly due to lung and cardiovascular injury. The virus responsible for COVID-19—severe acute respiratory syndrome coronavirus 2—gains entry into host cells via ACE2 (angiotensin-converting enzyme 2). ACE2 is a primary enzyme within the key counter-regulatory pathway of the renin-angiotensin system (RAS), which acts to oppose the actions of Ang (angiotensin) II by generating Ang-(1–7) to reduce inflammation and fibrosis and mitigate end organ damage. As COVID-19 spans multiple organ systems linked to the cardiovascular system, it is imperative to understand clearly how severe acute respiratory syndrome coronavirus 2 may affect the multifaceted RAS. In addition, recognition of the role of ACE2 and the RAS in COVID-19 has renewed interest in its role in the pathophysiology of cardiovascular disease in general. We provide researchers with a framework of best practices in basic and clinical research to interrogate the RAS using appropriate methodology, especially those who are relatively new to the field. This is crucial, as there are many limitations inherent in investigating the RAS in experimental models and in humans. We discuss sound methodological approaches to quantifying enzyme content and activity (ACE, ACE2), peptides (Ang II, Ang-[1–7]), and receptors (types 1 and 2 Ang II receptors, Mas receptor). Our goal is to ensure appropriate research methodology for investigations of the RAS in patients with severe acute respiratory syndrome coronavirus 2 and COVID-19 to ensure optimal rigor and reproducibility and appropriate interpretation of results from these investigations.

ABSTRACTBackground:Lymphocytic duodenosis (LD) defined as increased intraepithelial lymphocytes >25 intraepithelial lymphocytes (IELs) per 100 epithelial cells with normal villous architecture is associated with many gastrointestinal (GI) disorders. We aim to assess the rate and outcome of LD in children and perform a systematic review.Method:We reviewed all children (<18 years) who underwent esophagogastroduodenoscopy (EGD) with duodenal biopsy between January 2000 and June 2019 to identify LD cases and control group. Demographics, clinical, and pathologic information were reviewed and recorded. A systematic review including our findings was performed.Results:During the study period 12,744 children underwent an EGD with biopsies. Of those, we identified 426 children with LD (3%) and 474 controls. The median age in years was 10.7 and 12.6 and there were 254 (60%) and 278 (59%) girls in the LD and control group, respectively. The most common presenting symptoms in both groups were abdominal pain (52%), gastroesophageal acid reflux disease (18%), diarrhea (16%), and vomiting (12%). Diarrhea (21% vs 12%, P < 0.001) and constipation (2% vs 0.4%, P = 0.021) were statistically different between the LD and control group, respectively. Median follow‐up (range) is 3.6 (0.0, 190.9) and 3.1 (0.0, 194.2) in the LD and control group, respectively. CD (5% vs 0%, P < 0.001), Crohn disease (9% vs 3%, P = 0.003) and Helicobacter pylori gastritis (3% vs 1%, P = 0.021) were more common in the LD group.Conclusions:The Rate of LD in children is similar to reported rate in adults. In the absence of Crohn disease, CD or H. Pylori, LD seems to be a benign and transient histologic finding in children.

Goal: The goal of this study was to estimate the impact of verification bias on the diagnostic accuracy of immunoglobulin A tissue transglutaminase (IgA tTG) in detecting celiac disease as reported by an authoritative meta-analysis, the 2016 Comparative Effectiveness Review (CER). Background: Verification bias is introduced to diagnostic accuracy studies when screening test results impact the decision to verify disease status. Materials and Methods: We adjusted the sensitivity and specificity of IgA tTG reported by the 2016 CER with the proportion of IgA tTG positive and negative individuals who are referred for confirmatory small bowel biopsy. We performed a systematic review from January 1, 2007, to July 19, 2017, to determine these referral rates. Results: The systematic review identified 793 articles of which 9 met inclusion criteria (n=36,477). Overall, 3.6% [95% confidence interval (CI): 1.1%-10.9%] of IgA tTG negative and 79.2.2% (95% CI: 65.0%-88.7%) of IgA tTG positive individuals were referred for biopsy. Adjusting for these referral rates the 2016 CER reported sensitivity of IgA tTG dropped from 92.6% (95% CI: 90.2%-94.5%) to 57.1% (95% CI: 35.4%-76.4%) and the specificity increased from 97.6% (95% CI: 96.3%-98.5%) to 99.6% (95% CI: 98.4%-99.9%). Conclusions: The CER may have largely overestimated the sensitivity of IgA tTG due to a failure to account for verification bias. These findings suggest caution in the interpretation of a negative IgA tTG to rule out celiac disease in clinical practice. More broadly, they highlight the impact of verification bias on diagnostic accuracy estimates and suggest that studies at risk for this bias be excluded from systematic reviews.