Assessment of intestinal permeability and orocecal transit time in patients with systemic sclerosis: analysis of relationships with epidemiologic and clinical parameters

The Clinical Significance of Serum Biomarkers of the Intestinal Barrier in Systemic Sclerosis: A Cross-Sectional Study

Systemic sclerosis (SSc) is an immune-mediated connective tissue disease. Recent studies reported differences in the composition of intestinal microbiota (dysbiosis) in patients with SSc compared to nonsclerodermic subjects. Dysbiosis may disrupt the intestinal barrier, which leads to immunological activation via microbial antigen and metabolite translocation. The study aimed to assess the differences in intestinal permeability between SSc patients and controls and to examine the correlation between intestinal permeability and complications of SSc. The study comprised 50 patients with SSc and 30 matched subjects. Serum intestinal permeability markers: intestinal fatty acid binding protein, claudin-3, and lipopolysaccharides (LPS) were determined using an enzyme-linked immunosorbent assay. SSc patients had a significantly increased concentration of LPS compared to control subjects (232.30 [149.00-347.70] versus 161.00 [83.92-252.20] pg/mL, p < 0.05). The patients with shorter SSc duration (≤6 years) had an increased concentration of LPS and claudin-3 compared to the subgroup with longer disease length: LPS (280.75 [167.30-403.40] versus 186.00 [98.12-275.90] pg/mL, p < 0.05), and claudin-3 (16.99 [12.41-39.59] versus 13.54 [10.29-15.47] ng/mL, p < 0.05). The patients with esophageal dysmotility had a decreased LPS level compared to those without this complication (188.05 [102.31-264.40] versus 283.95 [203.20-356.30] pg/mL, p < 0.05). Increased intestinal permeability in SSc may exacerbate the course of the disease and increase the risk of developing complications. Lower LPS levels in SSc might be a hallmark of esophageal dysmotility.

Systemic sclerosis gastrointestinal dysmotility: risk factors, pathophysiology, diagnosis and management

Nearly all patients with systemic sclerosis (SSc) are negatively affected by dysfunction in the gastrointestinal tract, and the severity of gastrointestinal disease in SSc correlates with high mortality. The clinical complications of this dysfunction are heterogeneous and include gastro-oesophageal reflux disease, gastroparesis, small intestinal bacterial overgrowth, intestinal pseudo-obstruction, malabsorption and the requirement for total parenteral nutrition. The abnormal gastrointestinal physiology that promotes the clinical manifestations of SSc gastrointestinal disease throughout the gastrointestinal tract are diverse and present a range of therapeutic targets. Furthermore, the armamentarium of medications and non-pharmacological interventions that can benefit affected patients has substantially expanded in the past 10 years, and research is increasingly focused in this area. Here, we review the details of the gastrointestinal complications in SSc, tie physiological abnormalities to clinical manifestations, detail the roles of standard and novel therapies and lay a foundation for future investigative work.

The Gut Microbial Metabolite Trimethylamine N-Oxide is Linked to Specific Complications of Systemic Sclerosis

Background

Systemic sclerosis (SSc) is a rare immune-mediated connective tissue disease characterized by fibrosis of the skin and internal organs, whose pathogenesis is not fully understood. Recent studies have revealed dysbiosis in patients with systemic sclerosis and have indicated the possible role of the microbiota and its metabolites in the pathogenesis of the disease. Trimethylamine N-oxide (TMAO) is a compound produced by dysbiotic microbiota observed at higher concentrations in several autoimmune diseases.

Objective

To determine concentrations of the bacteria-derived metabolite TMAO in patients with systemic sclerosis and to assess possible correlation between TMAO and a specific manifestation of the disease.

Patients and Methods

The study included 63 patients with SSc and 47 matched control subjects. The concentration of TMAO was measured with high-performance liquid chromatography.

Results

Plasma TMAO level was significantly increased in patients with SSc (283.0 [188.5-367.5] ng/mL versus 205.5 [101.0-318.0] ng/mL; p < 0.01). An increased concentration of TMAO was observed in patients with concomitant interstitial lung disease (ILD) (302.0 ng/mL [212.0-385.5] ng/mL versus 204.0 [135.5-292.0] ng/mL; p < 0.01) and esophageal dysmotility (289.75 [213.75-387.5] ng/mL versus 209.5 ng/mL [141.5-315.0] ng/mL; p < 0.05) compared to patients without these complications. Furthermore, TMAO concentration exhibited significant correlation with markers of heart involvement (left ventricle ejection fraction, NT-proBNP), marker of ILD severity and Scleroderma Clinical Trials Consortium Damage Index.

Conclusion

The concentration of TMAO, gut microbiota-associated metabolite, is increased in systemic sclerosis, particularly in patients with advanced organ involvement. This is the first study evaluating plasma TMAO in systemic sclerosis. Bacterial metabolites may be a link between dysbiosis and organ involvement in the course of the disease. Modulation of gut bacterial-derived metabolites may represent a new therapeutic approach in the management of systemic sclerosis.

Comparing Clinical, Imaging, and Physiological Correlates of Intestinal Pseudo-Obstruction: Systemic Sclerosis vs Amyloidosis and Paraneoplastic Syndrome

INTRODUCTION

Intestinal pseudo-obstruction is characterized by impaired transit and luminal dilation in the absence of mechanical obstruction. Our study aims to describe the clinical, radiographic, and physiological findings in pseudo-obstruction associated with systemic sclerosis (SSc), amyloidosis, and paraneoplastic syndrome.

METHODS

A retrospective cohort of patients evaluated at our institution between January 1, 2008, and August 1, 2018, was assembled. Clinical, imaging, and physiological characteristics were abstracted from electronic medical records.

RESULTS

We identified 100 cases of pseudo-obstruction (55 SSc, 27 amyloidosis, and 18 paraneoplastic). Female population predominance was seen in SSc (71%) vs male population in amyloidosis (74%). Most common symptom was abdominal bloating in all 3 groups. Vomiting was more common in SSc than amyloidosis (73% vs 46%, P = 0.02). Diarrhea was more common in amyloidosis and SSc compared with paraneoplastic (81% and 67% vs 28%, P < 0.01). Weight loss (>5%) was more common in SSc compared with amyloidosis and paraneoplastic (78% vs 31% and 17%, P < 0.0001). Only small bowel dilation was seen in 79%, 40%, and 44% and only large bowel dilation in 2%, 44%, and 44% of patients in SSc, amyloidosis, and paraneoplastic, respectively. Five of 8 SSc patients had myopathic and 3 of 5 paraneoplastic had neuropathic involvement on gastroduodenal manometry.

DISCUSSION

SSc-associated pseudo-obstruction demonstrates female population predominance and presents with vomiting, diarrhea, and weight loss. Amyloidosis-associated pseudo-obstruction shows male population predominance. Small bowel is more commonly involved than large bowel on both imaging and transit studies in SSc. Myopathic involvement was more common in SSc, contrary to neuropathic in paraneoplastic syndrome.

Risk factors associated with intestinal permeability in an adult population: A systematic review

BACKGROUND

Increased intestinal permeability (IP) involves the loss of integrity between the cells of the small intestine. IP has been suggested to contribute to the pathogenesis and exacerbation of many chronic diseases. Many potential risk factors for IP are proposed in contemporary literature. The purpose of this review is to identify the most significant risk factors for IP.

METHODS

A systematic search of literature published up until September 2018 in the PubMed, EMBASE, CINAHL, and Scopus databases was conducted.

RESULTS

A total of 47 articles met the inclusion criteria. Elevated levels of proinflammatory markers, dyslipidaemia, hyperglycaemia, insulin resistance, anthropometric measurements resembling obesity, advanced disease severity, comorbidity and the consumption of a Western-style diet were identified as the strongest risk factors for altered intestinal integrity. The risk of IP increases when coupled with a multiple disease state or combined with other environmental risk factors. Furthermore, many of the identified risk factors such as anthropometric measurements and biomarkers were external from intestinal health and rather resembled a metabolic-like condition.

CONCLUSIONS

This review identified a number of potential risk factors for IP, ranging from biomarkers to anthropometric measurements, demographics, dietary intake and chronic diseases. These risk factors warrant the attention of clinicians and other healthcare providers to aid the identification of potential patients at risk of altered IP. Further research needs to examine whether the identified risk factors are homogeneous with the diagnosis of IP or whether the disease state influences the association.

ASCA (Anti-Saccharomyces cerevisiae Antibody) in Patients With Scleroderma

OBJECTIVES

The majority of scleroderma (SSc) patients present gastrointestinal involvement. Motility is usually compromised but few studies address permeability changes in the intestinal wall. ASCA (anti-Saccharomyces cerevisiae antibodies) positivity is associated with increased intestinal permeability. In this study we aimed to investigate ASCA positivity in SSc patients and its association with clinical, serological and epidemiological data.

METHODS

Seventy-four SSc patients and 57 healthy controls were studied for ASCA (IgG and IgA) positivity by ELISA. ASCA positivity was associated with demographic, clinical severity index (by Medsger score) and serological data in SSc patients.

RESULTS

ASCA-IgG was positive in 32/74 (43.2%) patients of the SSc group and 1/57 (1.7%) of controls (p < 0.0001); ASCA-IgA was positive in 12/74 (16.2%) of the SSc group and 3/57 (5.2%) of controls (p = 0.05). In univariate analysis, ASCA-IgG presence was associated positively with African ethnic background (p < 0.001) and negatively associated with anticentromere antibodies (p = 0.013); ASCA-IgA had a negative association with Medsger score (p = 0.05). In multivariate analysis ASCA-IgG associated independently only with African ethnic background.

CONCLUSION

Positivity for ASCA-IgG and ASCA-IgA is higher among scleroderma patients than controls. African descendants have more positivity for ASCA-IgG. ASCA-IgA is less frequent in patients with a more severe disease.

Points to consider for clinical trials of the gastrointestinal tract in systemic sclerosis

The pathogenesis of gastrointestinal tract involvement in SSc is not fully understood. However, gastrointestinal signs and symptoms are very common. Trials to test therapies, with rare exceptions, should be double-blind, randomized trials with either active therapy or placebo as comparators. Trial duration will vary dependent on the anticipated therapy and should usually be 6-24 weeks long, although some motility trials may need to be 52 weeks. As in any well-controlled trial, inclusion and exclusion criteria should encourage relatively uniform patients with sufficiently active disease to discern response, importantly considering disease duration. Previous therapy, co-morbid conditions, potentially confounding and/or concomitant therapy should be considered. Outcome measures should include both objective/semi-objective and subjective measures, although validated measures are not frequent and design needs to consider using only validated measures. Unvalidated measures can be included to validate them for future use. A full analysis plan should be completed before study commencement, including the method to account for missing data.

Lactulose breath test to assess oro-cecal transit delay and estimate esophageal dysmotility in scleroderma patients

OBJECTIVES

To assess the correlation between delayed oro-cecal transit time (OCTT) and esophageal motility abnormalities in a cohort of systemic sclerosis (SSc) patients.

METHODS

We prospectively enrolled 50 consecutive SSc patients and 60 healthy volunteers (HVs) as controls. Both groups underwent glucose breath test (GBT) to exclude small intestine bacterial overgrowth, lactulose hydrogen, and octanoic acid breath tests (LHBT and OBT) to measure OCTT and gastric emptying (GE), respectively, and manometry to assess esophageal motility.

RESULTS

Thirty-one (63%) SSc patients presented ineffective esophageal motility (IEM) compared with 3 HVs (5%; P<0.01), 37 (74%) had an abnormal OCTT compared with 4 HVs (7%; P <0.01), and 16 (32%) had an altered GE compared with 4 HVs (7%; P <0.01). The median OCTT and gastric t½ were longer in SSc than in HVs (165 min vs. 101 min and 125 min vs. 78 min, respectively; P <0.01). A delayed GE was present in 12/37 (32%), whereas IEM in 27/37 (73%) SSc patients with prolonged OCTT. The prevalence of IEM increased in parallel with the prolongation of OCTT (31% when OCTT<150 min, 73% when OCTT≥150 min, and up to 85% when OCTT>180 min, P<0.01).

CONCLUSIONS

Abnormalities of both esophageal and small intestine motility are frequent in SSc patients and esophageal motility is altered in most cases with small bowel involvement. Delayed GE plays a limited role in prolonging OCTT. LHBT is a non-invasive, cheap, well-tolerated diagnostic tool that may be useful to estimate intestinal involvement and also to estimate a higher risk of esophageal hypomotility in SSc patients.

Profile of gastrointestinal involvement in patients with systemic sclerosis

Systemic sclerosis (SSc) is a chronic autoimmune connective tissue disease. Of the numerous organ manifestations, involvement of the upper and lower gastrointestinal tract (GIT) appears to be the most frequent with regard to the clinical symptoms. However, as the frequency and clinical relevance of GI involvement in patients with SSc are not known in detail, the German network of the systemic sclerosis (DNSS) has developed a detailed questionnaire to evaluate the extent and profile of gastrointestinal involvement in SSc patients. The multi-symptom questionnaire was used at baseline and after 1 year in registered patients of the DNSS. In addition, the results were compared with gastrointestinal disorders in patients with SSc and other rheumatic diseases, as well as with the medical history of the patients. In total, 90 patients were included in the study. The results of the study show that in reality, a much higher (nearly all) percentage of (98,9%) patients than expected suffer from GI-symptoms, regardless of the stage of their disease. Of these, meteorism (87,8%) was the most common followed by coughing/sore voice (77,8%), heartburn (daytime 68,9%, nighttime 53,3%), diarrhea (67,8%), stomach ache (68,9%) and nausea (61,1%). Although SSc patients were treated according to the respective recommendations, only limited improvements with regard to GI-symptoms could be achieved after 1 year of follow-up. In addition, the study revealed that the multi-symptom questionnaire is a useful tool to contribute to identify the gastrointestinal sequelae in systemic sclerosis.

[Gastrointestinal involvement in systemic sclerosis. An underestimated complication]

Systemic sclerosis (SSc) belongs to the family of autoimmune connective tissue diseases and is still a challenge to every practicing physician. The disorder is characterized by progressing fibrosis of the skin and internal organs, abnormal activation of the immune system, and distinct changes in microcirculation. Although it is rare--with a prevalence of about 20:100000--patients need to be cared for in a daily setting. In general thickening of the skin is the first sign of the disease, so dermatologists are most frequently consulted first. Two subtypes exist, limited and diffuse forms. Both entities usually involve internal organs, and therefore interdisciplinary cooperation is mandatory. The increased morbidity and mortality depend predominantly on the grade of involvement of the affected organs. Therefore it is essential to diagnose systemic sclerosis early and to identify and monitor all complications closely. In this respect gastrointestinal involvement is frequently neglected, owing to its primarily non-life-threatening character, resulting in substantially delayed therapy.

Gastric and enteric involvement in progressive systemic sclerosis

Progressive systemic sclerosis (PSS) is a chronic multisystem disease characterized by excess deposition of connective tissue in skin and internal organs, associated with microvasculature changes and immunologic abnormalities. Involvement of the gastrointestinal tract may occur in 2 stages, a neuropathic disorder followed by a myopathy. Gastric emptying is delayed in 10% to 75% of patients and correlates with symptoms of early satiety, bloating, and emesis. Compliance of the fundus is increased although perception of fullness is normal. Myoelectric abnormalities have been found in some studies. Treatments include metoclopramide, cisapride, and erythromycin. Bleeding from telangiectasias and watermelon stomach is treated endoscopically. Small bowel involvement in PSS occurs in 17% to 57% of patients. The migrating motor complexes are reduced or absent, predisposing to bacterial overgrowth. Malabsorption may also be due to pancreatic insufficiency. Barium enemas demonstrate pancolonic involvement in 10% to 50% of patients with PSS. Wide-mouthed diverticuli, involving all layers of the intestinal wall, are characteristic. Pseudoobstruction may respond to octreotide or prucalopride therapy. Complications include pneumatosis cystoides intestinalis, stercoral ulcerations, and perforation. Fecal incontinence may be due to dysfunction of the internal anal sphincter, a smooth muscle responsible for most of the resting anal sphincter pressure. Anal manometry may show a reduction or loss of the rectoanal inhibitory reflex. Treatments include biofeedback, sacral nerve stimulation, and surgery. PSS involves the gastrointestinal tract from the mouth to the anus. Studies are needed to define effective treatments in these diseases, which cause great morbidity.

New diseases derived or associated with the tight junction

The space between neighboring epithelial cells is sealed by the tight junction (TJ). When this seal is leaky, such as in the proximal tubule of the kidney or the gallbladder, substances may cross the epithelium between the cells (paracellular pathway). Yet, when TJs are really hermetic, as is the case in the epithelium of the urinary bladder or the colon, substances can mainly cross the epithelium through the transcellular pathway. The structure of the TJ involves (so far) some 50-odd protein species. Failure of any of these components causes a variety of diseases, some of them so serious that fetuses are not viable. A fast-growing number of diseases are recognized to depend or involve alterations in the TJ. These include autoimmune diseases, in which intestinal TJs allow the passage of antigens from the intestinal flora, challenging the immune system to produce antibodies that may cross react with proteins in the brain, thyroid gland or pancreas. TJs are also involved in cancer development, infections, allergies, etc. The present article does not catalogue all TJ diseases known so far, but describes one of each type as illustration. It also depicts the efforts being made to find pharmaceutical agents that would seal faulty TJs or release their grip to allow for the passage of large molecules through the upper respiratory and digestive tracts, such as insulin, thyroid, appetite-regulatory peptide, etc.

Gastrointestinal manifestations in Hungarian scleroderma patients

Systemic sclerosis (SSc) is a chronic connective tissue disease characterized by fibrosis and destruction of the microvasculature. Increased deposition of collagen and other extracellular matrix components affects not only the skin but most of the internal organs including lungs, heart, kidneys and the gastrointestinal (GI) tract. Within the GI tract, esophageal involvements are most frequently seen features. However, abnormalities in the small intestine, colon and anorectum may also occur. A retrospective study was performed to investigate the frequency and clinical relevances of GI involvement in patients with SSc. Charts of altogether 246 SSc patients were reviewed. This patient population included 40 males and 206 females, with a mean age of 54.2 years. In general, 176 of 246 patients (71.5%) had GI symptoms. Esophageal involvement including gastro-esophageal reflux disease (GERD), aperistalsis, pseudodiverticuli, etc. was the most common (62.6%). In addition, diseases of the stomach (31.7%), dysfunctions of the colon and anorectum (11.4%), as well as sclerosis of the biliary tract and other pancreato-biliary disorders (9.8%) also occurred. Diarrhea and malabsorption resulted in cachexia and other secondary complications leading to death in two cases. Our results support that GI manifestations are rather common in SSc. Apart from the esophagus, other GI complications in SSc are usually mild, however, early recognition is necessary to improve quality of life.

Systematic review: pathophysiology and management of gastrointestinal dysmotility in systemic sclerosis (scleroderma)

Gastrointestinal dysmotility in systemic sclerosis (scleroderma) is prevalent in 90% of patients, increasing morbidity and in some cases mortality. The resultant gastrointestinal complications are usually extensive, involving many regions of the gut from the oesophagus to the anus. Collagen replacement of vascular and enteric smooth muscle results in hypomotility, lumen dilatation, tensile rigidity and eventual loss of organ functions. The aim of this paper is to provide an overview of systemic sclerosis-related gastrointestinal dysmotility and available/potential therapeutic options. We evaluated published data on the pathophysiology and management of gastrointestinal dysmotility in systemic sclerosis patients using the MEDLINE database for English and non-English articles from 1966 to July 2005. Based on this systematic review, lifestyle and medical therapy approaches are preferred as they often improve and/or ameliorate symptoms. Surgery is only recommended with serious, rare complications such as bowel perforation or ischaemia. Alternative therapies such as acupuncture-based therapies are well tolerated, with clinical improvement and may be of potential therapeutic benefit for systemic sclerosis gastrointestinal dysmotility. Further elucidation of initiating and persistent mechanisms of systemic sclerosis-related gastrointestinal dysmotility will optimize the development of a multidisciplinary and more directed treatment regimen.

Role of the intestinal tight junction modulator zonulin in the pathogenesis of type I diabetes in BB diabetic-prone rats

Increased intestinal permeability has been observed in numerous human autoimmune diseases, including type-1 diabetes (T1D) and its' animal model, the BB-wor diabetic prone rat. We have recently described zonulin, a protein that regulates intercellular tight junctions. The objective of this study was to establish whether zonulin-dependent increased intestinal permeability plays a role in the pathogenesis of T1D. In the BB diabetic-prone rat model of T1D, intestinal intraluminal zonulin levels were elevated 35-fold compared to control BB diabetic-resistant rats. Zonulin up-regulation was coincident with decreased small intestinal transepithelial electrical resistance, and was followed by the production of autoantibodies against pancreatic beta cells, which preceded the onset of clinically evident T1D by approximately 25 days. In those diabetic prone rats that did not progress to diabetes, both intraluminal zonulin and transepithelial electrical resistance were similar to those detected in diabetic-resistant animal controls. Blockade of the zonulin receptor reduced the cumulative incidence of T1D by 70%, despite the persistence of intraluminal zonulin up-regulation. Moreover, treatment responders did not seroconvert to islet cell antibodies. Combined together, these findings suggest that the zonulin-induced loss in small intestinal barrier function is involved in the pathogenesis of T1D in the BB diabetic-prone animal model.