Elevated levels of faecal calprotectin in primary Sjögren's syndrome is common and associated with concomitant organic gastrointestinal disease

Clinical features and risk factors of primary Sjögren's syndrome complicated with severe pneumonia: a case-control study

OBJECTIVES

To analyze clinical characteristics, risk factors, pathogen distribution, and prognostic markers in primary Sjögren's syndrome (pSS) patients with severe pneumonia (SP) compared to those without severe pneumonia (NSP).

METHODS

This case-control study included 24 hospitalized pSS patients with SP and 96 NSP at the first affiliated hospital of Soochow university from June 2014 to May 2023. Data encompassing demographics, comorbidities, treatments, and laboratory results were retrospectively collected. Univariate and multivariate regression analyses, ROC curves, and statistical analyses using SPSS 23.0 assessed risk factors. The study retrospectively analyzed clinical features and risk factors, highlighting distinct parameters between pSS patients with and without SP.

RESULTS

Marked differences were observed in several parameters: pSS activity(P < 0.001), white blood cell (P = 0.043), lymphocyte (P < 0.001), neutrophils (P = 0.042), C-reactive protein (P = 0.042), and CD8+ T cell (P = 0.017). Notably, lymphocyte count and SS activity demonstrated robust discrimination ability (AUC > 0.85). C-reactive protein (CRP), procalcitonin, CD4+ T cell, and IgA showed significant associations with SP; higher CRP levels correlated with increased risk, while lower CD4+ T cell and IgA levels associated with increased risk. SS activity significantly impacted outcomes. Various biomarkers exhibited diverse discriminatory abilities but lacked strong predictive associations with outcomes.

CONCLUSION

pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. Lymphocyte count and SS activity emerged as robust discriminators. Higher CRP levels correlated with increased risk of SP, while lower CD4+T cell and IgA levels associated with increased risk. SS activity significantly impacted patient outcomes. Key Points • pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. • Lymphocyte count and SS activity emerged as robust discriminators. • Higher CRP levels correlated with increased risk of SP, while lower CD4+ T cell and IgA levels associated with decreased risk. • SS activity significantly impacted patient outcomes.

Gut inflammation associated with age and Alzheimer's disease pathology: a human cohort study

Age-related disease may be mediated by low levels of chronic inflammation ("inflammaging"). Recent work suggests that gut microbes can contribute to inflammation via degradation of the intestinal barrier. While aging and age-related diseases including Alzheimer's disease (AD) are linked to altered microbiome composition and higher levels of gut microbial components in systemic circulation, the role of intestinal inflammation remains unclear. To investigate whether greater gut inflammation is associated with advanced age and AD pathology, we assessed fecal samples from older adults to measure calprotectin, an established marker of intestinal inflammation which is elevated in diseases of gut barrier integrity. Multiple regression with maximum likelihood estimation and Satorra-Bentler corrections were used to test relationships between fecal calprotectin and clinical diagnosis, participant age, cerebrospinal fluid biomarkers of AD pathology, amyloid burden measured using 11C-Pittsburgh compound B positron emission tomography (PiB PET) imaging, and performance on cognitive tests measuring executive function and verbal learning and recall. Calprotectin levels were elevated in advanced age and were higher in participants diagnosed with amyloid-confirmed AD dementia. Additionally, among individuals with AD dementia, higher calprotectin was associated with greater amyloid burden as measured with PiB PET. Exploratory analyses indicated that calprotectin levels were also associated with cerebrospinal fluid markers of AD, and with lower verbal memory function even among cognitively unimpaired participants. Taken together, these findings suggest that intestinal inflammation is linked with brain pathology even in the earliest disease stages. Moreover, intestinal inflammation may exacerbate the progression toward AD.

Evaluation of the Role of Faecal Calprotectin in the Management of Psoriatic Patients under Treatment with Biologic Drugs

Background: Fecal calprotectin has emerged as a significant, validated, and non-invasive biomarker allowing for the evaluation of inflammatory bowel disease. Our study assessed the reliability of the use of faecal calprotectin as a valuable tool in the management of psoriatic patients on biological therapy. Methods: This was a single-centre prospective study including adult patients affected by moderate-to-severe psoriasis starting biological therapy. Faecal calprotectin levels were evaluated at baseline and at week 24 (W24) of treatment in all enrolled patients. Results: Overall, 129 patients were enrolled. The mean baseline faecal calprotectin levels were 74.7 μg/g and a significant reduction was detected at W24 of biological therapy (57.5 μg/g). An analysis of faecal CP values stratified by therapy type was performed. No significant reduction was assessed at W24 for any of the anti-IL17 drugs, whereas a significant reduction was detected for all IL23 inhibitors. Conclusions: Our study showed the potential use of faecal CP levels as a valuable tool for exploring intestinal inflammation in the management of psoriatic patients undergoing treatment with biologic drugs.

The Involvement of Alarmins in the Pathogenesis of Sjögren's Syndrome

Sjögren’s syndrome (SS) is a chronic autoimmune disease that affects exocrine glands, primarily the salivary and lachrymal glands. It is characterized by lymphoplasmacytic infiltration of the glandular tissues, ultimately leading to their dysfunction and destruction. Besides classic dry eyes and dry mouth defined as sicca syndrome, patients affected by the disease also typically display symptoms such as fatigue, pain and in more than 50% of cases, systemic manifestations such as arthritis, interstitial lung involvement, neurological involvement and an increased risk of lymphoma. The pathophysiological mechanisms underlying SS still remain elusive. The crucial role of innate immunity has been advocated in recent years regarding the pathogenesis of pSS, especially in the initiation and progression toward autoimmunity. Alarmins are endogenous molecules that belong to the large family of damage associated molecular pattern (DAMP). Alarmins are rapidly released, ensuing cell injury and interacting with pattern recognition receptors (PRR) such as toll-like receptors (TLR) to recruit and activate cells of the innate immune system and to promote adaptive immunity responses. This review highlights the current knowledge of various alarmins and their role in the pathogenesis of pSS.

Diseases which cause generalized peripheral neuropathy: a systematic review

PURPOSE

Peripheral autonomic neuropathy, including enteric neuropathy, may be subtle and unrecognized for several years. Diagnosis of enteric neuropathy demands complicated examinations such as full-thickness bowel biopsy. We hypothesized that knowledge about simultaneous occurrence of different types of neuropathy would lead to faster recognition and diagnosis of autonomic/enteric neuropathy. The aim of the present systematic review was to increase the awareness of disease groups causing autonomic and enteric neuropathy along with sensorimotor neuropathy.

METHODS

A systematic search strategy was used in PubMed, Embase and Web of Science. First, 4978 articles were identified. Review of titles/abstracts rendered exclusion of animal studies, articles not written in English or full-length, case reports, conference abstracts and duplicates until 357 articles remained. The full-length evaluation resulted in 35 studies (27 non-systematic reviews) which described objectively verified peripheral autonomic, enteric and sensorimotor neuropathy within the same disease.

RESULTS

Diabetes is the most common disease in society rendering generalized peripheral neuropathy. Accumulation of tissue deposits in amyloidosis, Lewy body disorders and sarcoidosis lead to widespread peripheral neuropathy. Several autoimmune disorders such as systemic sclerosis and primary Sjögren's syndrome present themselves with neuropathy. Paraneoplastic neuropathy may appear prior to symptoms from the malignancy. Both the infection per se, as well as the autoimmune response to the infection, i.e., Guillain-Barré syndrome, may lead to widespread peripheral neuropathy. Hereditary disorders with disturbed metabolism lead to intermittent attacks of neuropathy.

CONCLUSIONS

The major causes of generalized peripheral neuropathy are diabetes, diseases with tissue deposits, autoimmunity, infections, malignancy and metabolic diseases.

Increased intestinal permeability in primary Sjögren's syndrome and multiple sclerosis

There is increasing evidence suggesting a role of intestinal dysfunction in a number of autoimmune diseases. Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease with a documented increased level of intestinal inflammation, whereas multiple sclerosis (MS) is an organ-specific autoimmune disease known to exhibit increased intestinal permeability. In this study we determine to what extent intestinal inflammation, analysed by a faecal calprotectin ELISA, is accompanied by altered intestinal wall permeability, as measured by a lactulose and mannitol intestinal absorption assay. Intestinal permeability was increased in both pSS and MS patients, while faecal calprotectin was elevated in pSS but normal in MS. Our findings suggest different mechanisms mediating a leaky gut in these two diseases: in pSS there is autoimmune attack directly on the intestinal wall; in MS, with autoimmunity being limited to the CNS, it may be due to a disturbed CNS regulation of enteric nerve function.

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Intestinal permeability analysed by sugar absorption is increased in primary Sjögren’s syndrome and multiple sclerosis.

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Intestinal wall inflammation as determined by faecal calprotectin is observed in pSS but not in MS.

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Leaky gut may be due to autoimmune targeting of the intestinal wall in pSS and to disturbed intestinal innervation in MS.

Longitudinal Characterisation of the Gastrointestinal Tract Microbiome in Systemic Sclerosis

Objectives

To evaluate changes in microbial composition and the evolution of gastrointestinal tract (GIT) symptoms in systemic sclerosis (SSc).

Methods

Adult SSc patients provided stool specimens every 3 months over the course of 1 year. Participants completed the University of California, Los Angeles (UCLA) GIT 2.0 questionnaire to assess GIT symptom severity at each stool collection. The microbiota from these samples were determined by Illumina HiSeq 2500 16S ribosomal RNA sequencing (Illumina, Inc., San Diego, California, USA). Mixed effect models evaluated changes in GIT symptoms and microbial composition over time.

Results

Among 19 patients with SSc (female; 89.5%; median age: 51.3 years), the median disease duration was 7 years and the baseline total GIT 2.0 score was 0.7 (standard deviation: 0.6). The majority of participants (63%) provided at least four stool samples over the course of the 12-month study. Patients with longer disease durations had increased GIT symptoms over the course of the study. There was no difference in the course of GIT symptoms over time between patients with limited versus diffuse cutaneous disease. The relative abundances of specific genera did not change over time within individual subjects. After controlling for age, sex, ethnicity, disease duration, and SSc subtype (i.e., limited versus diffuse), low abundance of Bacteroides was associated with increased GIT symptoms over time.

Conclusion

This study is the first to have longitudinally characterised the lower GIT microbiome in SSc patients and demonstrated relative stability of genera abundance over the course of 1 year. The findings provide additional evidence that specific genera are associated with SSc-GIT symptoms and warrant further evaluation in larger SSc studies.

Transcription profiling of peripheral B cells in antibody-positive primary Sjögren's syndrome reveals upregulated expression of CX3CR1 and a type I and type II interferon signature

B cells play a key role in the pathogenesis of primary Sjögren's syndrome (pSS). The aim of this study was to analyse the transcriptome of CD19+ B cells from patients with pSS and healthy controls to decipher the B cell-specific contribution to pSS. RNA from purified CD19+ B cells from 12 anti-SSA antibody-positive untreated female patients with pSS and 20 healthy blood donors was subjected to whole transcriptome sequencing. A false discovery rate corrected significance threshold of α < 0.05 was applied to define differential gene expression. As validation, gene expression in B cells from 17 patients with pSS and 16 healthy controls was analysed using a targeted gene panel. RNA-sequencing identified 4047 differentially expressed autosomal genes in pSS B cells. Upregulated expression of type I and type II interferon (IFN)-induced genes was observed, establishing an IFN signature in pSS B cells. Among the top upregulated and validated genes were CX3CR1, encoding the fractalkine receptor involved in regulation of B-cell malignancies, CCL5/RANTES and CCR1. Increased expression of several members of the TNF superfamily was also identified; TNFSF4/Ox40L, TNFSF10/TRAIL, TNFSF13B/BAFF, TNFRSF17/BCMA as well as S100A8 and -A9/calprotectin, TLR7, STAT1 and STAT2. Among genes with downregulated expression in pSS B cells were SOCS1 and SOCS3, CD70 and TNFAIP3/A20. We conclude that B cells from patients with anti-SSA antibody-positive pSS display immune activation with upregulated expression of chemokines, chemokine receptors and a prominent type I and type II IFN signature, while suppressors of cytokine signalling are downregulated. This adds insight into the autoimmune process and suggests potential targets for future functional studies.

Severe intestinal dysbiosis is prevalent in primary Sjögren's syndrome and is associated with systemic disease activity

Background

Altered microbial composition of the intestine, commonly referred to as dysbiosis, has been associated with several autoimmune diseases including primary Sjögren’s syndrome (pSS). The aims of the current study were to study the intestinal microbial balance in pSS and to identify clinical features associated with dysbiosis.

Methods

Forty-two consecutive pSS patients and 35 age-matched and sex-matched control subjects were included in the study in an open clinic setting. Stool samples were analyzed for intestinal dysbiosis using a validated 16S rRNA-based microbiota test (GA-map™ Dysbiosis Test; Genetic Analysis, Oslo, Norway). Dysbiosis and severe dysbiosis were defined in accordance with the manufacturer’s instructions. Patients were evaluated with regard to disease activity (European League Against Rheumatism (EULAR) Sjögren’s Syndrome Disease Activity Index (ESSDAI) and Clinical ESSDAI (ClinESSDAI)). In addition, patients were examined for laboratory and serological features of pSS as well as fecal calprotectin levels.

Furthermore, patients were investigated regarding patient-reported outcomes for pSS (EULAR Sjögren’s Syndrome Patient Reported Index (ESSPRI)) and irritable bowel syndrome (IBS)-like symptoms according to the Rome III criteria.

Results

Severe dysbiosis was more prevalent in pSS patients in comparison to controls (21 vs 3%; p = 0.018). Subjects with pSS and severe dysbiosis had higher disease activity as evaluated by the ESSDAI total score (13 vs 5; p = 0.049) and the ClinESSDAI total score (12 vs 5; p = 0.049), lower levels of complement component 4 (0.11 vs 0.17 g/L; p = 0.004), as well as higher levels of fecal calprotectin (110 vs 33 μg/g; p = 0.001) compared to the other pSS patients. In contrast, severe dysbiosis among pSS patients was not associated with disease duration, IBS-like symptoms, or the ESSPRI total score.

Conclusions

Severe intestinal dysbiosis is a prevalent finding in pSS and is associated both with clinical and laboratory markers of systemic disease activity as well as gastrointestinal inflammation. Further studies are warranted to elucidate a potential causative link between dysbiosis and pSS.