Thomas Greuter

Hepatic sinusoids in liver injury, inflammation, and fibrosis: new pathophysiological insights.

Changes of hepatic sinusoids are crucial in the pathogenesis of liver cirrhosis and portal hypertension. Liver injury leads to distinct morphological abnormalities such as loss of sinusoidal fenestration, vasoconstriction, and angiogenesis as well as molecular changes. Communication between the two key cells in this hepatic microenvironment—hepatic stellate cells (HSC) and sinusoidal endothelial cells (SEC)—has been studied for many years and several canonical pathways have been elucidated, such as decreased eNOS activity or increased PDGF and TGF-β production leading to activation and migration of HSC. In recent studies, alternative pathways of intercellular communication in liver diseases have been described such as cell-derived extracellular vesicles called exosomes, which deliver cell compounds to their target cells. Moreover, such extracellular vesicles may link injury to inflammation in alcoholic hepatitis. While inflammation leading to liver fibrosis has been studied in detail, in some circumstances pathways other than the known canonical inflammatory pathways may contribute to hepatic fibrogenesis. For example, in congestive hepatopathy, sinusoidal dilatation and fibrosis have been shown to be mediated by non-inflammatory mechanisms and associated with sinusoidal thrombi. A recently developed murine model further enables experimental studies of this disease entity. Increasing knowledge about these alternative disease pathways in liver injury, inflammation, and fibrosis may reveal possible target molecules for future therapies. This article builds upon a seminar given at the recent 3rd JSGE International Topic Conference in Sendai, Japan, and reviews the areas outlined above.

Long-Term Treatment of Eosinophilic Esophagitis With Swallowed Topical Corticosteroids: Development and Evaluation of a Therapeutic Concept

Objectives:Swallowed topical corticosteroids (STCs) are efficacious in inducing and presumably maintaining remission in patients with active eosinophilic esophagitis (EoE). Hitherto, it has not been evaluated whether long-lasting remission can be achieved, and whether treatment can be stopped once patients have achieved this remission.Methods:Since 2007, EoE patients included into a large database at the Swiss EoE Clinics were put on STCs as induction/maintenance therapy. Disease activity was assessed on an annual basis. In patients who achieved long-lasting (≥6 months) clinical, endoscopic, and histological (=deep) remission, treatment was stopped. Data on all patients treated using this therapeutic strategy were analyzed retrospectively.Results:Of the 351 patients, 33 (9.4%) who were treated with STCs achieved deep remission. Median age of remitters at disease onset was 32.6 years (interquartile range (IQR) 19.1–49.3), and diagnostic delay was 5.4 years (IQR 1.2–11.4). Deep remission was achieved after 89.0 weeks (IQR 64.6–173.8). Female gender was the only independent prognostic factor for achieving deep remission (odds ratio (OR) 2.518, 95% confidence interval (CI) 1.203–5.269). Overall, STCs were stopped after 104.7 weeks (IQR 65.5–176.6). No mucosal damage was observed upon histological examination. In 27 of the 33 remitters (81.8%), a clinical relapse occurred after a median of 22.4 weeks (95% CI 5.1–39.7). Six remitters (18.2%) did not experience a clinical relapse during a follow-up of 35.1 weeks (IQR 18.3–44.9). Hence, a total of 1.7% (6/351) patients were able to discontinue STCs in the long term.Conclusions:Long-term EoE treatment with STCs was well tolerated, but only a minority achieved deep remission. Female gender is the only prognostic factor for attainment of such remission. After treatment cessation, the majority experienced a clinical relapse.

Alicaforsen, an antisense inhibitor of ICAM-1, as treatment for chronic refractory pouchitis after proctocolectomy: A case series

Background and aims The published data about the efficacy of the intercellular adhesion molecule-1 (ICAM-1) antisense oligonucleotide termed alicaforsen in inflammatory bowel disease (IBD) is rather inconsistent. This case series analyzes its efficacy in chronic refractory pouchitis, after proctocolectomy. Methods We performed a retrospective analysis on all patients who had received at least one dose of alicaforsen for IBD at three referral centers in Switzerland. We assessed the drug’s efficacy in patients treated for chronic refractory pouchitis, by comparing the clinical and/or endoscopic disease activity at baseline with a 2–3-month follow-up visit. Results We identified 22 patients who had received at least one dose. Among them, 13 patients were being treated for chronic refractory pouchitis. These patients had a median age of 38.0 years (95% CI 21.0–69.0) and five were female (38.5%). The median time since pouch surgery was 102.5 months (95% CI 16.0–288.0), with a median pouchitis duration of 16.0 months (95% CI 4.0–216.0). At 2–3 months after therapy, clinical and endoscopic disease activity was significantly reduced (stool frequency 9.0 versus 6.0, the Pouchitis Disease Activity Index (PDAI) clinical subscore was 4.0 versus 1.0, and the endoscopic disease activity was 4.0 versus 2.0). Clinical improvement was achieved in 11 out of 13 pouchitis patients (84.6%); however, a relapse was observed in nine of these patients (81.8%). The median time from clinical improvement to relapse was 16 weeks (95% CI 9.0–23.0). Conclusions Alicaforsen seemed to be efficacious in inducing clinical and/or endoscopic improvement in chronic refractory pouchitis and may be a promising treatment alternative in those patients; however, given the high proportion of relapse, one 6-week course of alicaforsen may not be sufficient.

Anti-TNF Treatment for Extraintestinal Manifestations of Inflammatory Bowel Disease in the Swiss IBD Cohort Study

Background: Extraintestinal manifestations (EIMs) in patients with inflammatory bowel disease (IBD) are frequently observed. Little is known about the efficacy of anti–tumor necrosis factor (TNF) in EIM management. We assessed the effect of 3 anti-TNF agents (infliximab, adalimumab, and certolizumab pegol) on EIM evolution. Methods: Data on 1249 patients from the Swiss IBD Cohort Study (SIBDCS) were analyzed. All EIMs were diagnosed by relevant specialists. Response was classified into improvement, stable disease, and clinical worsening based on the physicians interpretation. Results: Of the 366 patients with at least 1 EIM, 213 (58.2%) were ever treated with an anti-TNF. A total of 299 treatments were started for 355 EIMs. Patients with EIM were significantly more often treated with anti-TNF compared with those without EIM (58.2% versus 21.0%, P < 0.001). Infliximab was the most frequently used drug (63.2%). In more than 71.8%, a clinical response of the underlying EIM to anti-TNF therapy was observed. In 92 patients (43.2%), anti-TNF treatments were started for the purpose of treating EIM rather than IBD. Response rates to anti-TNF were generally good and best for psoriasis, aphthous stomatitis, uveitis, and peripheral arthritis. In 11 patients, 14 EIM occurred under anti-TNF treatment. Conclusions: Anti-TNF was frequently used among patients with EIM. In more than 40%, anti-TNF treatments are started to treat EIM rather than IBD. Given the good response rates, anti-TNF seems to be a valuable option in the treatment of EIM, whereas appearance of EIM under anti-TNF does not seem to be a source of considerable concern.

Extraintestinal Manifestations of Pediatric Inflammatory Bowel Disease: Prevalence, Presentation, and Anti-tnf Treatment

Background: There is a paucity of data on extraintestinal manifestations (EIM) and their treatment in pediatric patients with inflammatory bowel disease (IBD). Methods: Since 2008, the Pediatric Swiss IBD Cohort Study has collected data on the pediatric IBD population in Switzerland. Data on 329 patients were analyzed retrospectively. Results: A total of 55 patients (16.7%) experienced 1–4 EIM (39 Crohn disease, 12 ulcerative colitis, and 4 IBD-unclassified patients). At IBD onset, presence of EIM was more frequent than in the adult population (8.5% vs 5.0%, P = 0.014). EIM were more frequent in Crohn disease when compared to ulcerative colitis/IBD-unclassified (22.5% vs 10.3%, P = 0.003). The most prevalent EIM were peripheral arthritis (26/329, 7.9%) and aphthous stomatitis (24/329, 7.3%). Approximately 27.6% of all EIM appeared before IBD diagnosis. Median time between IBD diagnosis and occurrence of first EIM was 1 month (−37.5–149.0). Thirty-one of the 55 patients (56.4%) were treated with 1 or more anti–tumor necrosis factor (TNF) agents. IBD patients with EIM were more likely to be treated with anti-TNF compared to those without (56.4% vs 35.0%, P = 0.003). Response rates to anti-TNF depended on underlying EIM and were best for peripheral arthritis (61.5%) and uveitis (66.7%). Conclusions: In a cohort of pediatric patients with IBD, EIM were frequently encountered. In up to 30%, EIM appeared before IBD diagnosis. Knowledge of these findings may translate into an increased awareness of underlying IBD, thereby decreasing diagnostic delay. Anti-TNF for the treatment of certain EIM is effective, although a substantial proportion of new EIM may present despite ongoing anti-TNF therapy.

Cogan’s Syndrome in Patients With Inflammatory Bowel Disease – A Case Series

BACKGROUND Cogans syndrome (CSy) is a very rare autoimmune disorder, mainly affecting the inner ear and the eye, and is associated with inflammatory bowel disease (IBD). METHODS This was a European Crohns and Colitis Organisation (ECCO) retrospective observational study, performed as part of the CONFER project. A call to all ECCO members was made to report concomitant CSy and inflammatory bowel disease (IBD) cases. Clinical data were recorded in a standardized questionnaire. RESULTS This international case series reports on 22 concomitant CSy-IBD cases from 14 large medical centres. Mean duration of IBD until diagnosis of CSy was 8.7 years (range 0.0-38.0) and mean age at CSy diagnosis was 44.6 years (range 9.0-67.0). Six patients had underlying ulcerative colitis (UC) and 16 had Crohns disease. Eleven patients (50%) had active disease at CSy diagnosis. Sixteen patients were under IBD treatment at the time of CSy diagnosis, of whom 6 (37.5%) were on anti-tumour necrosis factor (TNF). Seven out of 10 patients, who were treated for CSy with immunomodulators (mostly with corticosteroids), demonstrated at least partial response. CONCLUSION This is the largest CSy-IBD case series so far. Although CSy is considered to be an autoimmune disease and is associated with IBD, immunomodulatory IBD maintenance treatment and even anti-TNF therapy do not seem to prevent disease onset. Moreover, IBD disease activity does not seem to trigger CSy. However, vigilance may prompt early diagnosis and directed intervention with corticosteroids at inception may potentially hinder audiovestibular deterioration. Finally, vigilance and awareness may also offer a better setting to study the pathophysiological mechanisms of this rare but debilitating phenomenon.

Therapeutic opportunities for alcoholic steatohepatitis and nonalcoholic steatohepatitis: exploiting similarities and differences in pathogenesis

Alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH) are among the most frequent causes of chronic liver disease in the United States. Although the two entities are triggered by different etiologies - chronic alcohol consumption (ASH) and obesity-associated lipotoxicity (NASH) - they share overlapping histological and clinical features owing to common pathogenic mechanisms. These pathogenic processes include altered hepatocyte lipid metabolism, organelle dysfunction (i.e., ER stress), hepatocyte apoptosis, innate immune system activation, and hepatic stellate cell activation. Nonetheless, there are several disease-specific molecular signaling pathways, such as differential pathway activation downstream of TLR4 (MyD88-dependence in NASH versus MyD88-independence in ASH), inflammasome activation and IL-1β signaling in ASH, insulin resistance and lipotoxicity in NASH, and dysregulation of different microRNAs, which clearly highlight that ASH and NASH are two distinct biological entities. Both pathogenic similarities and differences have therapeutic implications. In this Review, we discuss these pathogenic mechanisms and their therapeutic implications for each disease, focusing on both shared and distinct targets.

Skin Manifestations of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) with its two main subtypes Crohn’s disease and ulcerative colitis is not restricted to the gastrointestinal tract. Indeed, so-called extraintestinal manifestations (EIMs) are frequent and considerably affect morbidity and mortality. The prevalence of EIMs ranges from 6 to 47%. In up to one quarter of the patients, EIMs can present even before an IBD diagnosis is established. The pathophysiology of EIMs remains elusive, although data from clinical trials demonstrating anti-tumor necrosis factor (TNF) efficacy suggest a common pathogenic link between intestinal and extraintestinal disease activity. However, not all EIMs parallel intestinal disease. Skin lesions are usually classified based on their pathophysiological association with the underlying intestinal disease into four categories: (1) specific, (2) reactive, (3) associated, and (4) treatment-induced manifestations. Cutaneous manifestations include erythema nodosum (EN), pyoderma gangrenosum (PG), Sweet’s syndrome, and oral lesions, with EN being the most commonly reported and PG showing the most debilitating disease course. Anti-TNF-induced skin reactions are a new, but increasingly recognized phenomenon, which can be eventually misinterpreted as psoriatic lesions. Medical treatment modalities are limited with topical and systemic steroids being the most frequently employed agents. If EIMs parallel intestinal disease activity, the therapeutic cornerstone usually is the management of underlying intestinal disease activity rather than direct treatment of the EIMs. However, increasing evidence for anti-TNF agents’ efficacy in EIM management has changed the approach to complicating and debilitating disease courses. In the case of anti-TNF-induced lesions, topical steroids are usually sufficient and discontinuation of anti-TNF is seldom warranted. In this review, we summarize current knowledge on cutaneous EIMs, their diagnostic criteria and clinical presentation, natural history, pathogenesis, and treatment options.

Celiac disease is misdiagnosed based on serology only in a substantial proportion of patients

Background: Although the diagnostic process in celiac disease (CeD) has been addressed in several international guidelines, little is known about the actual proceeding in current clinical practice. This study investigated the initial presentation, the diagnostic process, follow-up evaluations, and adherence to a gluten-free diet in CeD patients in a real-life setting in Switzerland from a patient’s perspective. Methods: We performed a large patient survey among unselected CeD patients in Switzerland. Results: A total of 1689 patients were analyzed. The vast majority complained of both gastrointestinal and nonspecific symptoms (71.5%), whereas 1.8% reported an asymptomatic disease course. A total of 35.8% CeD patients were diagnosed by a nongastroenterologist. The diagnostic process differed between nongastroenterologists and gastroenterologists, with the latter more often using duodenal biopsy alone or in combination with serology (94.7% vs. 63.0%) and nongastroenterologists more frequently establishing the diagnosis without endoscopy (37.0% vs. 5.3%, P<0.001). Follow-up serology after 6 months was performed only in half of all patients (49.4%), whereas 69.9% had at least 1 follow-up serology within the first year after diet initiation. About 39.7% had a follow-up endoscopy with duodenal biopsies (after a median of 12 mo; range, 1 to 600 mo). The likelihood of receiving any follow-up examination was higher in patients initially diagnosed by a gastroenterologist. Conclusions: A significant proportion of CeD patients are diagnosed by nongastroenterologists. Under the diagnostic lead of the latter, more than a third of the patients receive their diagnosis on the basis of a positive serology and/or genetics only, in evident violation of current diagnostic guidelines, which may lead to an overdiagnosis of this entity.

Eosinophilic Esophagitis: Relationship of Subepithelial Eosinophilic Inflammation With Epithelial Histology, Endoscopy, Blood Eosinophils, and Symptoms

Objectives:For technical reasons, the histologic characterization of eosinophilic esophagitis (EoE)-specific alterations is almost exclusively based on those found in the esophageal epithelium, whereas little is known about subepithelial abnormalities. In this study, we aimed to systematically assess the nature of subepithelial histologic alterations, and analyze their relationship with epithelial histologic findings, endoscopic features, and symptoms.Methods:Adult patients with established EoE diagnosis were prospectively included during a yearly follow-up visit. Patients underwent assessment of clinical, endoscopic, and histologic disease activity using EoE-specific scores.Results:We included 200 EoE patients (mean age 43.5±15.7 years, 74% males) with a median peak count of 36 intraepithelial eosinophils/hpf (IQR 14−84). The following histologic features were identified in the subepithelial layer: eosinophilic infiltration (median peak count of 20 eosinophils/hpf (IQR 10−51)), eosinophil degranulation (43%), fibrosis (82%), and lymphoid follicles (56%). Peak intraepithelial eosinophil counts were higher, identical, and lower when compared to the subepithelial layer in 62.5%, 7%, and 30.5% of patients, respectively. Anti-eosinophilic treatment at inclusion did not influence the relation between subepithelial and epithelial peak eosinophil counts. Subepithelial histologic activity correlated with epithelial histologic activity (rho 0.331, P<0.001), endoscopic severity (rho 0.208, P=0.003), and symptom severity (rho 0.179, P=0.011). Forty percent (21/52) of patients with <15 intraepithelial eosinophils/hpf had subepithelial peak counts of ≥15/hpf.Conclusions:There is a significant but modest correlation between subepithelial histologic activity and epithelial histologic activity, endoscopic severity, and symptom severity. The long-term clinical impact of assessing subepithelial alterations in EoE needs to be further elucidated.