Gastrointestinal manifestations of systemic sclerosis: An updated review

The effect of gut microbiome and plasma metabolome on systemic sclerosis: a bidirectional two-sample Mendelian randomization study

Background

Cellular and molecular biology, combined with research on the human microbiome and metabolome, have provided new insights into the pathogenesis of systemic sclerosis (SSc). However, most studies on gut microbiota (GM) and metabolome in SSc are observational studies. The impact of confounding factors and reverse causation leads to different insights. To shed light on this matter, we utilized Mendelian randomization (MR) to determine the causal effect of GM/metabolites on SSc.

Methods

Based on summary-level data from genome-wide association studies, bidirectional Two-sample MR was conducted involving 196 GM, 1400 plasma metabolism, and 9,095 SSc. Inverse Variance Weighting (IVW) was mainly used for effect estimation.

Results

Forward MR analysis found that three GM and two plasma metabolites are causally related to SSc. IVW results showed Victivallaceae (family) (OR, 1.469; 95%CI, 1.099-1.963; p = 0.009) and LachnospiraceaeUCG004 (genus) (OR, 1.548; 95%CI, 1.020-2.349; p = 0.04) were risk factor of SSc. Conversely, Prevotella7 (genus) (OR, 0.759; 95%CI, 0.578-0.997; p = 0.048)was a protective factor of SSc. The results on plasma metabolites indicated that Pregnenediol disulfate (C21H34O8S2) levels (OR, 1.164; 95%CI, 1.006-1.347; p = 0.041)was a risk factor of SSc, while Sphingomyelin (d18:1/19:0, d19:1/18:0) levels (OR, 0.821; 95%CI, 0.677-0.996; p = 0.045)was a protective factor of SSc. Reverse MR analysis did not find causally relationship between SSc and the above GM/plasma metabolites.

Conclusion

Our results revealed the causally effect between GM/plasma metabolites and SSc. These findings provided new insights into the mechanism of SSc. In particular, we demonstrated Prevotella7 was a protective factor of SSc despite its controversial role in SSc in previous researches.

Clinical significance of the anti-Nucleolar Organizer Region 90 antibodies (NOR90) in systemic sclerosis: Analysis of the European Scleroderma Trials and Research (EUSTAR) cohort and a systematic literature review

BACKGROUND

The anti-Nucleolar Organizer Region 90 antibodies (NOR90) are rare antinuclear antibodies (ANA) reported in systemic sclerosis (SSc). Especially due to low prevalence, the clinical relevance of NOR90 in SSc remains uncertain.

OBJECTIVES

To analyze the clinical associations of NOR90 in patients with SSc in a multicentric cohort.

METHODS

Post-hoc, cross-sectional study of prospectively collected data from the European Scleroderma Trials and Research (EUSTAR) database, with additional information on NOR90. Further, we performed a systematic literature search, using the terms "systemic sclerosis" and "NOR90" across three databases: Medline via PubMed, Scopus, and Thomson Reuters' Web of Science Core Collection, from inception to November 1st, 2023.

RESULTS

Overall, 1318 patients with SSc were included (mean age 58.3 ± 13.7 years, 81.3 % female), of whom 44 (3.3 %) were positive for NOR90. Of these, 32 were also positive for one of the SSc-criteria antibodies: 9/44 (20.5 %) for anti-topoisomerase I, 18/42 (42.9 %) for anti-centromere, and 5/40 (12.5 %) for anti-RNA polymerase III. NOR90-positive patients were more frequently female, had lower modified Rodnan skin score (mRSS), and lower prevalence of upper and lower gastrointestinal (GI) symptoms compared to NOR90-negative patients. In multivariable analysis, NOR90 remained significantly associated with lower mRSS and less frequent GI symptoms. The literature search identified 17 articles, including a total number of 87 NOR90-positive out of 3357 SSc patients, corresponding to an overall prevalence of 2.6 %.

CONCLUSION

To our best knowledge, this is the largest SSc cohort tested for NOR90 to date, confirming the NOR90 prevalence in SSc patients is around 3 %.

Severity and impact of digestive impairment perceived by patients with systemic sclerosis: a cross-sectional study

OBJECTIVES

To describe the severity and impact of gastrointestinal involvement in patients with systemic sclerosis (SSc) and identify associated factors.

PATIENTS AND METHODS

Non-controlled cross-sectional study of patients with SSc (2013 American College of Rheumatology/European League Against Rheumatism criteria). The main variables were severity of gastrointestinal involvement according to the University of California, Los Angeles Scleroderma Clinical Trials Consortium Gastrointestinal Tract 2.0 instrument (UCLA SCTC GIT 2.0) and dysphagia according to the Eating Assessment Tool-10 (EAT-10). We evaluated reflux, distension, diarrhoea, faecal soilage, constipation, emotional well-being and social functioning, as well as dysphagia. Clinical and epidemiological data were collected using the Mini Nutritional Assessment Short Form (MNA-SF) and the EuroQol-5D-3L. The degree of skin fibrosis was assessed using the modified Rodnan skin score (mRSS). Multivariate models were constructed to analyse factors associated with gastrointestinal involvement and dysphagia.

RESULTS

Of the 75 patients with SSc included, 58.7% had moderate, severe or very severe reflux, 57.4% had constipation according to UCLA SCTC GIT 2.0 and 49.7% had abdominal distension. Gastrointestinal symptoms interfered significantly with social functioning (42.7%) and emotional well-being (40.0%). Dysphagia (EAT-10≥3) was recorded in 52% of patients, and according to MNA-SF poor nutrition in 30.7%, and clear malnutrition requiring a nutritional intervention in 5.3%. Multivariate adjustment revealed an association between severity of gastrointestinal symptoms according to the mRSS (β=0.249; p=0.002) and Visual Analogue Scale 3-Level EuroQol-5D (VAS-EQ-5D-3L) (β=-0.302; p=0.001), whereas presence of dysphagia was associated with the mRSS (OR=2.794; p=0.015), VAS-EQ-5D-3L (OR=0.950; p=0.005) and malnutrition (MNA-SF≤7; OR=3.920; p=0.041).

CONCLUSIONS

Patients with SSc frequently present severe gastrointestinal symptoms. These are associated with poor quality of life, more severe skin involvement and malnutrition.

Association between systemic sclerosis and risk of cerebrovascular and cardiovascular disease: a meta-analysis

We aimed to evaluate the association between systemic sclerosis (SSc) and major cerebrovascular/cardiovascular risks through a systematic approach. Databases were systematically searched from their inception to October 10, 2023 for studies comparing cerebrovascular/cardiovascular event rates between patients with SSc and controls. The primary outcome was the stroke risk in patients with SSc. Secondary outcomes included risk of myocardial infarction (MI), cardiovascular disease (CVD), peripheral vascular disease (PVD), and venous thromboembolism (VTE). Seventeen studies with 6,642,297 participants were included. SSc was associated with a significantly increased risk of stroke (HR, 1.64; 95% confidence interval [CI], 1.35-2.01), CVD (HR, 2.12; 95% CI, 1.36-3.3), MI (HR, 2.15; 95% CI, 1.23-3.77), VTE (HR, 2.75; 95% CI, 1.77-4.28), and PVD (HR, 5.23; 95% CI, 4.25-6.45). Subgroup analysis revealed a significantly increased stroke risk in the non-Asian group (HR, 1.55; 95% CI, 1.26-1.9), while the Asian group displayed a higher but not statistically significant risk (HR, 1.86; 95% CI, 0.97-3.55). The study found that SSc is associated with a significantly increased risk of cerebrovascular/cardiovascular events. These findings highlight the importance of vasculopathy in SSc and suggest the need for enhanced clinical monitoring and preventive measures in this high-risk population.

Treatable Traits in Systemic Sclerosis

Systemic sclerosis (SSc) is a chronic systemic disease within the spectrum of connective tissue diseases, specifically characterized by vascular abnormalities and inflammatory and fibrotic involvement of the skin and internal organs resulting in high morbidity and mortality. The clinical phenotype of SSc is heterogeneous, and serum autoantibodies together with the extent of skin involvement have a predictive value in the risk stratification. Current recommendations include an organ-based management according to the predominant involvement with only limited individual factors included in the treatment algorithm. Similar to what has been proposed for other chronic diseases, we hypothesize that a "treatable trait" approach based on relevant phenotypes and endotypes could address the unmet needs in SSc stratification and treatment to maximize the outcomes. We provide herein a comprehensive review and a critical discussion of the literature regarding potential treatable traits in SSc, focusing on established and candidate biomarkers, with the purpose of setting the bases for a precision medicine-based approach. The discussion, structured based on the organ involvement, allows to conjugate the pathogenetic mechanisms of tissue injury with the proposed predictors, particularly autoantibodies and other serum biomarkers. Ultimately, we are convinced that precision medicine is the ideal guide to manage a complex condition such as SSc for which available treatments are largely unsatisfactory.

When natural antibodies become pathogenic: autoantibodies targeted against G protein-coupled receptors in the pathogenesis of systemic sclerosis

Systemic sclerosis (SSc) is a chronic, multisystem connective tissue, and autoimmune disease with the highest case-specific mortality and complications among rheumatic diseases. It is characterized by complex and variable features such as autoimmunity and inflammation, vasculopathy, and fibrosis, which pose challenges in understanding the pathogenesis of the disease. Among the large variety of autoantibodies (Abs) present in the sera of patients suffering from SSc, functionally active Abs against G protein-coupled receptors (GPCRs), the most abundant integral membrane proteins, have drawn much attention over the last decades. These Abs play an essential role in regulating the immune system, and their functions are dysregulated in diverse pathological conditions. Emerging evidence indicates that functional Abs targeting GPCRs, such as angiotensin II type 1 receptor (AT1R) and the endothelin-1 type A receptor (ETAR), are altered in SSc. These Abs are part of a network with several GPCR Abs, such as those directed to the chemokine receptors or coagulative thrombin receptors. In this review, we summarize the effects of Abs against GPCRs in SSc pathologies. Extending the knowledge on pathophysiological roles of Abs against GPCRs could provide insights into a better understanding of GPCR contribution to SSc pathogenesis and therefore help in developing potential therapeutic strategies that intervene with pathological functions of these receptors.

Particularly severe form of refractory gastrointestinal involvement in systemic sclerosis

A woman with systemic sclerosis presents with a severe and rapidly progressive form of gastrointestinal involvement, mainly marked by recurrent refractory episodes of pseudo-obstruction, culminating in severe malnutrition and dependence of parenteral nutrition. The impact on her quality of life was extremely significant. As a last resort, she started intravenous immunoglobulin with progressive improvement of her symptoms, allowing for the reinstitution of oral diet and removal of parenteral nutrition. After more than 1 year, she maintains clinical stability. Systemic sclerosis has a heterogeneous phenotype, but gastrointestinal involvement is one of the most frequent. Severe manifestations are rare, but can lead to severe malnutrition and are associated with high morbidity and mortality rates. Their management is challenging, as the available treatments are still very limited. A better understanding of its pathophysiology, which seems to be unique, is essential to provide more effective treatments and improving quality of life.

The validity and reliability of the Swedish version of the Satisfaction with appearance scale for individuals with systemic sclerosis

Background

Systemic sclerosis (SSc) can lead to visible changes in appearance which could generate concerns among patients. Thus, valid questionnaires that capture these concerns are valuable to identify and communicate appearance concerns.

Objective

To determine aspects of the validity and reliability of the Swedish version of the Satisfaction with Appearance scale for individuals with SSc (SWAP-Swe in SSc).

Methods

Content validity was assessed by interviews. In a cross-sectional design, construct validity was evaluated by comparing the self-reported questionnaire SWAP-Swe in SSc to the Scleroderma Health Assessment Questionnaire (SSc HAQ), Patient Health Questionnaire-8 (PHQ-8), RAND-36, modified Rodnan skin score (mRSS), disease duration and age using Spearman's rank correlations (r_s ). Internal consistency was evaluated by Cronbach's alpha coefficient and corrected item-to-total correlations. Test-retest reliability was investigated using the intraclass correlation coefficient (ICC).

Results

Eleven patients and 10 health professionals participated in the assessment of content validity. For the other aspects of validity and reliability 134 patients (median age 62 years, women 81%, limited cutaneous SSc 75%) participated. Overall, the content validity was satisfactory. The SWAP-Swe in SSc correlated with SSc HAQ (HAQ-DI r_s  = 0.50, visual analogue scales r_s  = 0.24-0.41), PHQ-8 (r_s  = 0.46), RAND-36 (r_s  = -0.21 to -0.47), mRSS (r_s  = 0.28), disease duration (r_s  = -0.01) and age (r_s  = -0.15). The Cronbach's alpha coefficient was 0.92, corrected item-to-total correlations ⩾ 0.45 and the ICC 0.82.

Conclusion

The SWAP-Swe in SSc showed satisfactory content validity, sufficient and good internal consistency and sufficient test-retest reliability. It was more strongly associated with self-reported questionnaires than with physician-assessed skin involvement and age, indicating that appearance concerns in SSc seem to be multidimensional as earlier reported. Our study contributes with a thorough investigation of validity and reliability including aspects that have not been investigated before. However, evaluation of more validity aspects of the SWAP-Swe in SSc is suggested.

The classification of gastric antral vascular ectasia in cirrhotic patients by Versatile Intelligent Staining Technology

Background

Portal hypertensive gastropathy (PHG) and gastric antral vascular ectasia (GAVE) are two different pathologies that cause bleeding in cirrhotic patients. These two pathologies are still difficult to be distinguished by white light endoscopy (conventional), as they both appear as red spots in the gastric antral mucosa in the case of severe PHG. The aim of our study was to assess the efficacy of Versatile Intelligent Staining Technology (VIST) in comparison to histopathology in the diagnosis and classification of GAVE.

Methods

A cross-sectional study included 50 patients with liver cirrhosis recruited from Alexandria Main University Hospital. Patients with connective tissue diseases and chronic kidney disease were excluded. All patients were examined by both conventional white light endoscopy (WLE) and image enhancement technology (VIST) using Sonoscape HD500 endoscope. GAVE was diagnosed as tortuous columns of ectatic vessels in the gastric antrum. Histopathological examination was used as the standard tool for the diagnosis of GAVE.

Results

A total of 50 patients were included, 28 patients (56 %) were diagnosed as GAVE by pathology vs 22 (44 %) as non-GAVE. Twenty-three of 28 (78.6 %) cases of GAVE were detected by VIST. VIST had superior sensitivity than WLE in the detection of GAVE, 82.1 % vs 7.1 %, while WLE had higher specificity 95.5 % vs 59.1 % by VIST. There was statistical significance between VIST and pathology in the diagnosis of GAVE, p<0.035, but no statistical significance between WLE and pathology. VIST has identified two types of GAVE: focal in 12/28 cases and diffuse in 11/28, and five were not diagnosed by VIST.

Conclusions

Versatile Intelligent Staining Technology could be used as an alternative tool to histopathological diagnosis of GAVE. GAVE can present as a focal group of ectatic vessels which adds a new class to GAVE classification that was previously misdiagnosed.

Gastroparesis in systemic sclerosis: a detailed analysis using whole-gut scintigraphy

OBJECTIVES

Gastroparesis is a common complication of SSc. We sought to determine the degree of overlap between gastroparesis and dysmotility in other areas of the gut, correlate our findings with gastrointestinal (GI) symptoms, and examine associations between gastroparesis and SSc features.

METHODS

Whole-gut scintigraphy was performed on SSc patients who were enrolled in the Johns Hopkins Scleroderma Cohort, for whom detailed longitudinal clinical and serologic data are collected. A subset of patients completed the University of California Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument 2.0 (UCLA GIT 2.0) to quantify their GI symptoms. We examined associations between the presence and severity of gastroparesis, GI symptoms, and SSc clinical features.

RESULTS

Ninety-seven SSc patients with and without GI symptoms underwent whole-gut scintigraphy and completed the gastric emptying study. Of the 97, 34 (35%) met criteria for gastroparesis. Of the measures assessed, delayed liquid emptying captured more patients with delayed gastric transit than delayed solid emptying (74% vs 55%), and percentage liquid emptying correlated best with GIT Reflux (ρ = -0.33, P = 0.01) and Distension (ρ = -0.30, P = 0.03) scores. Of 33 patients with gastroparesis, 30 (91%) had abnormal transit in other areas of the GI tract. Higher anti-centromere protein B (CENP-B) titres correlated with slower gastric emptying (ρ = -0.26, P = 0.03), but no specific clinical features of SSc were associated with gastroparesis.

CONCLUSIONS

Gastric emptying of liquids when given alongside solids may be more sensitive and provide a more clinically relevant measure of gastroparesis in SSc than solid gastric emptying or liquid gastric emptying alone. SSc patients with gastroparesis frequently have dysmotility in other areas of the GI tract, underscoring the need for whole-gut scintigraphy to evaluate the entire gut.

Systemic Scleroderma-Definition, Clinical Picture and Laboratory Diagnostics

(1) Background: Scleroderma (Sc) is a rare connective tissue disease classified as an autoimmune disorder. The pathogenesis of this disease is not fully understood. (2) Methods: This article reviews the literature on systemic scleroderma (SSc). A review of available scientific articles was conducted using the PubMed database with a time range of January 1985 to December 2021. (3) Results and Conclusions: The article is a review of information on epidemiology, criteria for diagnosis, pathogenesis, a variety of clinical pictures and the possibility of laboratory diagnostic in the diagnosis and monitoring of systemic scleroderma.