Gastrointestinal Symptoms and Elevated Levels of Anti-Saccharomyces cerevisiae Antibodies Are Associated with Higher Disease Activity in Colombian Patients with Spondyloarthritis

The potential pathogenic role of gut microbiota in rheumatic diseases: a human-centred narrative review

A growing amount of evidence suggests that gut microbiota plays an important role in human health, including a possible role in the pathogenesis of rheumatic and musculoskeletal diseases (RMD). We analysed the current evidence about the role of microbiota in rheumatoid arthritis (RA), spondyloarthritis (SpA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). In RA, we found a general consensus regarding a reduction of diversity and a specific bacterial signature, with consistent changes according to the different ethnic and geographical areas. The major pathogenetic role in RA is recognised for P. copri, L. salivarius and Collinsella, even if findings become more heterogeneous when considering established disease. In SpA, we found a relative gut abundance of Akkermansia, Coprococcus, Ruminoccocus and a relative reduction in Bacterioides and Firmicutes spp. Human and preclinical data suggest loss of mucosal barrier, increased permeability and Th1- and Th17-mediated inflammation. Additionally, HLA-B27 seems to play a role in shaping the intestinal microbiota and the consequent inflammation. In SLE, the typical gut microbiota signature was characterised by a reduction in the Firmicutes/Bacteroidetes ratio and by enrichment of Rhodococcus, Eggerthella, Klebsiella, Prevotella, Eubacterium and Flavonifractor, even if their real pathogenic impact remains unclear. In SSc, gastrointestinal dysbiosis is well documented with an increase of pro-inflammatory species (Fusobacterium, Prevotella, Ruminococcus, Akkermansia, γ-Proteobacteria, Erwinia, Trabsulsiella, Bifidobacterium, Lactobacillus, Firmicutes and Actinobacteria) and a reduction of species as Faecalibacterium, Clostridium, Bacteroidetes and Rikenella. In conclusion, seems possible to recognise a distinct gut microbiota profile for each RMD, even if significant differences in bacterial species do exist between different studies and there is a high risk of bias due to the cross-sectional nature of such studies. Therefore longitudinal studies are needed, especially on patients with preclinical and early disease, to investigate the real role of gut microbiota in the pathogenesis of RMD.

Serum biomarkers and their relationship to axial spondyloarthritis associated with inflammatory bowel diseases

Spondyloarthritis (SpA) constitute a group of chronic inflammatory immune-mediated rheumatic diseases characterized by genetic, clinical, and radiological features. Recent efforts have concentrated on identifying biomarkers linked to axial SpA associated with inflammatory bowel disease (IBD), offering predictive insights into disease onset, activity, and progression. Genetically, the significance of the HLA-B27 antigen is notably diminished in ankylosing spondylitis (AS) associated with IBD, but is heightened in concurrent sacroiliitis. Similarly, certain polymorphisms of endoplasmic reticulum aminopeptidase (ERAP-1) appear to be involved. Carriage of variant NOD2/CARD15 polymorphisms has been demonstrated to correlate with the risk of subclinical intestinal inflammation in AS. Biomarkers indicative of pro-inflammatory activity, including C-reactive protein (CRP) along with erythrocyte sedimentation rate (ESR), are among the consistent predictive biomarkers of disease progression. Nevertheless, these markers are not without limitations and exhibit relatively low sensitivity. Other promising markers encompass IL-6, serum calprotectin (s-CLP), serum amyloid (SAA), as well as biomarkers regulating bone formation such as metalloproteinase-3 (MMP-3) and Dickkopf-related protein 1 (DKK-1). Additional candidate indicators of structural changes in SpA patients include matrix metalloproteinase-3 (MMP-3), vascular endothelial growth factor (VEGF), tenascin C (TNC), and CD74 IgG. Fecal caprotein (f-CLP) levels over long-term follow-up of AS patients have demonstrated predictive value in anticipating the development of IBD. Serologic antibodies characteristic of IBD (ASCA, ANCA) have also been compared; however, results exhibit variability. In this review, we will focus on biomarkers associated with both axial SpA and idiopathic intestinal inflammation, notably enteropathic spondyloarthritis.

Colonoscopy aspiration lavages for mucosal metataxonomic profiling of spondylarthritis-associated gastrointestinal tract alterations

The study of the GI-tract microbiota of spondylarthritis (SpA) patients has focused on the analysis of feces samples, that picture mostly the luminal microbiota. The aim of this study was to determine the contribution of mucosal and luminal microbiome to the gut dysbiosis in SpA, using colonoscopy aspiration lavages (CAL), a recent alternative for regional studies of the GI-tract. We analyzed 59 CAL (from sigmoid colon and distal ileum), and 41 feces samples, from 32 SpA patients and 7 healthy individuals, using 16S rRNA gene-targeted metataxonomic profiling. It was found high prevalence of GI-tract manifestations among SpA patients (65.3%). Metataxonomic profiling, confirmed CAL samples from the lower GI tract (colon or ileum) presented a distinctive and undifferentiated bacteriome and separate from that found in feces' samples or in the beginning of the GI tract (oral cavity (OC)). Lower GI-tract samples and feces of SpA patients exhibited similar behavior to the microbiota of IBD group with reduced microbial richness and diversity, comparing to the healthy controls. Interestingly, it was found increase in proinflammatory taxa in SpA patients, such as Enterobacteriaceae family (mostly in the ileum), Succinivibrio spp. and Prevotella stercorea. Conversely, SpA patients presented significant decrease in the SCFA producers Coprococcus catus and Eubacterium biforme. Our data support the value of CAL samples for the regional study of GI-tract and contribute with information of potential "disruptor taxa" involved in the GI-tract associated disorders observed in SpA patients.

Implementation of screening criteria for inflammatory bowel disease in patients with spondyloarthritis and its association with disease and endoscopic activity

There is little literature on the implementation of screening criteria for inflammatory bowel disease (IBD) in patients with spondyloarthritis (SpA). This study aimed to apply IBD screening criteria in a group of patients with SpA without IBD diagnosis and correlate them to endoscopic findings and disease activity. A total of 82 patients with SpA were included. The IBD screening test and ileocolonoscopy with digital chromoendoscopy with magnification and histological analysis were performed. The data were analysed with Chi-square test/Fisher's exact test and multiple correspondence analysis. The major screening criteria found in 48.7% of the patients were associated with a history of infection (p = 0.037). Rectal bleeding was associated with the diagnosis of ankylosing spondylitis, acute inflammation, enthesitis and tissue architecture alteration in the ileum (p < 0.050). Diarrhoea was associated with a higher disease activity score (p = 0.02). Minor screening criteria were associated with painful inflammatory joint (p = 0.05), high disease activity score (p = 0.001) and high calprotectin levels (p = 0.050). Abdominal pain (36.9%) was associated with axial/peripheral compromise (p = 0.017), inflammatory back pain (p = 0.01), enthesitis (p = 0.021), higher disease activity score (p = 0.023) and acute ileum inflammation (p = 0.046). Diarrhoea of 4 weeks and abdominal pain were the most prevalent major and minor screening criteria, respectively, being related to early manifestations of inflammatory bowel compromise and higher disease activity score. This screening test grants a chance of opportune referral of SpA patients from rheumatology to gastroenterology.

Oral manifestations associated with inflammatory bowel disease and early endoscopic findings in patients with spondyloarthritis

BACKGROUND AND AIMS

Spondyloarthritis (SpA) is a group of autoinflammatory disorders, of which the primary extra-articular manifestation is inflammatory bowel disease (IBD). The oral cavity being a part of gastrointestinal tract, is significantly compromised in IBD, and in many cases, it is the first site of clinical manifestations of IBD. This study aimed to identify changes in the oral mucosa associated with the onset of IBD and their association with endoscopic/histological findings.

MATERIALS AND METHODS

The study assessed 80 patients with SpA and 52 healthy controls. Oral, rheumatological, and gastroenterological assessments were performed. The ileocolonoscopy was performed via digital magnification chromoendoscopy. The statistical analysis consisted of Chi-square, Fisher's exact, and multiple correspondence discriminant analysis tests.

RESULTS

From the disease cohort, 63.0% patients showed oral lesions (p = 0.050). These manifestations ranged from gingivitis (55.0%, p = 0.001), aphthous stomatitis (3.8%, p = 0.091), angular cheilitis (2.6%, p = 0.200), and perioral erythema with scaling (1.3%, p = 0.300). All patients who presented with alterations in colonic mucosa also had oral lesions associated with IBD (p = 0.039), specifically gingivitis/aphthous stomatitis (p = 0.029).

CONCLUSION

The patients with SpA without IBD present significant oral signs and symptoms. Gingivitis seems to be the most relevant because of its associations with early endoscopic and histological findings.

CLINICAL RELEVANCE

An integral approach to the diagnostic tests that includes evaluations of oral, rheumatological and gastroenterological tissues may favor timely attention and improve patients' quality of life.

Symptoms Compatible with Rome IV Functional Bowel Disorder in Patients with Ankylosing Spondylitis

OBJECTIVES

To determine the frequency of symptoms meeting Rome IV functional bowel disorder (FBD) in patients with ankylosing spondylitis (AS), investigate factors associated with FBD symptoms, and assess whether having FBD symptoms might influence AS disease activity.

METHODS

In this cross-sectional study, we enrolled 153 AS patients without known colonic ulcer and 56 sex- and age-matched controls to evaluate FBD (or its subtypes) symptoms. Disease characteristics were also evaluated in AS group.

RESULTS

Sixty (39.2%) of 153 AS patients had FBD symptoms, which was more prevalent than controls (23.2%). Besides, symptoms compatible with irritable bowel syndrome (IBS) and chronic diarrhea were detected in 18 and 43 AS patients respectively. For AS group, multivariable logistic regression analyses showed that symptoms of FBD, IBS, and chronic diarrhea were negatively associated with using non-steroidal anti-inflammatory drug (NSAID), and positively associated with comorbid fibromyalgia, respectively. In exploration about effects of FBD (or its subtypes) symptoms on AS disease activity by multivariable linear regression analyses, FBD symptoms and chronic diarrhea had universal positive associations with assessments of AS disease characteristics respectively.

CONCLUSION

Patients with AS had frequent symptoms compatible with FBD, IBS, and chronic diarrhea, proportions of which were lower in those with NSAID-use. The improvement of FBD symptoms and chronic diarrhea might be conducive to disease status of AS patients.

Frequency and distribution of Blastocystis sp. subtypes in patients with spondyloarthritis in Bogotá, Colombia

Although Blastocystis sp. is one of the most prevalent intestinal parasites worldwide, its role as a pathogen remains unclear. The use of molecular techniques to assess the genetic heterogeneity of Blastocystis sp. has become important to understand its function in some intestinal pathologies and if it is a key component of intestinal microbiota. Spondyloarthritis is a group of immune-mediated autoinflammatory diseases in which microbial dysbiosis in the gut (including parasites, bacteria and fungi) and intestinal inflammation are common features apparently associated with the pathophysiology of these disorders. This study included 74 patients diagnosed with spondyloarthritis and 57 systemically healthy individuals (included as controls), who were screened for intestinal parasites. Blastocystis sp. was detected in 68% and 73% of the patients with spondyloarthritis and controls, respectively. In faecal samples positive for Blastocystis sp., an 18S rRNA gene fragment of Blastocystis sp. was amplified and sequenced to identify their genetic sub-types. Patients with spondyloarthritis showed similar frequencies of ST1, ST2 and ST3 subtypes of Blastocystis sp. (30% each). The same subtypes were observed in controls, wherein almost 60% of the samples showed ST3. In addition, ST6 was found only in one sample from each group. ST1 subtype showed the greatest genetic variability. Although the same subtypes were detected in both patients with spondyloarthritis and controls, subtype prevalence studies conducted in Colombia indicate an association between ST3 and individuals with irritable bowel syndrome. This opens an interesting research avenue to further study of the epidemiology of Blastocystis sp. and its possible relationship with intestinal conditions in immunocompromised patients.

Biomarkers in axial spondyloarthritis and low back pain: a comprehensive review

The spectrum of axial spondyloarthritis (AxSpA) (including both non-radiographic and radiographic AxSpA), also known as ankylosing spondylitis AS, has achieved growing recognition. With the development of treatments not only effective in controlling disease activity but also in slowing radiographic progression, and given the cost and risk profiles of these novel treatments and the limitations of current clinical criteria, imaging and peripheral blood biomarkers (C-reactive protein, HLA-B27 testing), the need for better biomarkers has never been greater. The purpose of this review is to present up-to-date information on the biomarkers for the diagnosis for assessing disease diagnosis, activity, treatment response, and radiographic progression of AxSpA, and entails multiple search strings used to identify articles of interest published in PubMed and the Cochrane database up to May 1, 2021. We present the current status of research in serologic biomarkers such as cytokines, adipokines, matrix metalloproteinases, calprotectin, CD74, antibodies, bone turnover markers, and circulating protein fragments of cartilage and connective tissue degradation and other biomarkers. Despite a great deal of work, most serologic results have been disappointing and to date none perform better than CRP. Recent promising preliminary data for some has been published, but require further confirmation. Transcriptomic biomarkers such as micro-RNAs and genetic biomarkers also show promise to assist in diagnosis and possibly for radiographic severity, including a recently developed panel of genetic risk markers used in a polygenic risk score instrument in AS diagnosis. These need further confirmation and application in AS as well as in nr-AxSpA.

Association of Anti-Saccharomyces cerevisiae antibodies with clinical phenotype in spondyloarthritis patients

INTRODUCTION

The association between spondyloarthritis (SpA) and inflammatory bowel disease (IBD) has been shown in many studies. More recently, with the hypothesis that increased gut inflammation is of etiopathogenic importance in the development of SpA, evaluation of anti-Saccharomyces cerevisiae antibodies (ASCA) has gained increasing relevance.

OBJECTIVE

To study the status and frequency of ASCA in SpA patients and the association of these biomarkers with the clinical profile.

METHODS

An observational study was performed including 231 SpA patients treated with biologic therapy. ASCA IgA and IgG levels were determined by micro-enzyme-linked immunosorbent assay.

RESULTS

Our data showed an increase of ASCA IgA positivity among SpA patients. No relationship was found between ASCA status and the demographic aspects, genetic factors or clinical presentation, except for the association with IBD.

CONCLUSION

Our study confirms that ASCA IgA are elevated in SpA patients. Although there was no evidence of association with a particular disease phenotype, the existence of higher ASCA levels sustains a close relationship between gut and SpA.

Increasing of SIgA serum levels may reflect subclinical intestinal involvement in non-radiographic axial and peripheral spondyloarthritis

OBJECTIVE

The evidence shows that previous infection with enteric pathogens is a requirement to develop pSpA. Based on our previous results, variances on regulation of SIgA might influence SpA activity; thus, the aim of this study was to correlate the levels of SIgA, IgA against some enteric bacteria, and IL-17, IL-21, and IL-6 with clinical features in a group of SpA patients.

METHODS

Twenty-six pSpA, 20 nr-axSpA, 60 healthy volunteers (HV), and 34 patients with inflammatory bowel diseases (IBD) were included. All subjects were assessed to measure SIgA, total and specific IgA for enteric bacteria, and IL-17, IL-21, and IL-6 levels and clinical variables. For SpA patients, the diagnosis was verified 5 years after first evaluation to assess the risk of developing r-axSpA.

RESULTS

SIgA levels were significantly higher in SpA patients than in HV and IBD (p < 0.0001 and p = 0.047, respectively). However, no differences for SIgA neither total IgA were found among the SpA subtypes (p = 0.624). Only IL-6 was higher in SpA than HV (p = 0.013). An inverse correlation was demonstrated for SIgA and BASFI (r: - 0.45; p = 0.003), BASDAI (r: - 0.39; p = 0.0123), ASDAS-CRP (r: - 0.37; p = 0.014), and ASDAS-ESR (r: - 0.45; p = 0.0021). There was no evidence of risk of developing r-axSpA in patients who previously showed high levels of serum antibodies.

CONCLUSION

The results show that pSpA as well as nr-axSpA share a similar SIgA-intestinal involvement independently of a previous infection. This suggests that serum SIgA increases are evidence of subclinical intestinal compromise which could have influence on disease activity but not in this progression. Key Point • The levels of SIgA, IgA against some enteric bacteria, and IL-17, IL-21, and IL-6 are correlated with clinical features in a group of SpA patients.

Patients with enthesitis related arthritis show similar monocyte function pattern as seen in adult axial spondyloarthropathy

BACKGROUND

Axial SpA and Enthesitis related arthritis (ERA) patients show strong HLA-B27 association, gut dysbiosis, high toll like receptor (TLR)2 and 4 expression on monocytes, pro-inflammatory cytokine production and elevated levels of TLR4 endogenous ligands [tenascin-c (TNC) and myeloid related protein (MRP)8/14] in serum. Hence, we aimed to understand if these diseases have similar or different monocyte response.

METHODS

Fifty adult axial SpA, 52 ERA patients and 25 healthy controls (HC) were enrolled. Cytokine-producing monocyte frequency before and after stimulation with lipopolysaccharide (LPS), peptidoglycan (PG), TNC or MRP8 were measured in whole blood (WB) and synovial fluid mononuclear cells (SFMC) by flow cytometry. Also, IL-6, TNF, MMP3, TNC and MRP8/14 levels were measured in unstimulated and TLR ligand stimulated WB cultures supernatant by ELISA. Finally, the mRNA expression levels of TNF and IL-6 were measured post stimulation with LPS, TNC and MRP8.

RESULTS

At baseline, ERA and axial SpA patients showed similar TNF-α producing monocyte frequency which was higher than HC. MRP8 simulation led to increased TNF-α producing monocyte frequency in ERA than axial SpA. TNC and MRP8 stimulation led to similar IL-6 producing monocyte frequency in axial SpA and ERA patients. Baseline TNF and IL-6 producing monocyte frequency also modestly correlated with disease activity scores. TNF and IL-6 producing monocyte frequency increased in response to TLR stimulation in SFMC from both patients. In culture supernatants, axial SpA and ERA patients showed similar TNF production at baseline. MRP8 and TNC stimulation led to higher TNF production from ERA. Baseline IL-6 and MMP3 production was higher in ERA while TLR stimulation led to similar IL-6 and MMP3 production from axial SpA and ERA. TNC stimulation led to higher MMP3 production in ERA. mRNA expression in response to TLR stimulation was observed to be similar in axial SpA and ERA. TNC production was higher in ERA at baseline, while MRP8/14 production was higher in axial SpA than ERA post stimulation.

CONCLUSION

ERA patients have similar monocyte response to exogenous and endogenous TLR ligands as patients with axial SpA. This suggests that differences between pediatric and adult-onset SpA are minimal and they may have a common pathogenesis.

Biomarkers in Inflammatory Bowel Disease-Associated Spondyloarthritis: State of the Art and Unmet Needs

Inflammatory bowel disease-associated spondyloarthritis is a systemic disease characterized by the chronic inflammation of both the gastrointestinal tract and the musculoskeletal system. Since inflammatory bowel disease-associated spondyloarthritis has been associated with a significant diagnostic delay, which may lead to poor quality of life and progression of joint damage, efforts to discover new reliable and noninvasive diagnostic biomarkers have been made. We reviewed the state of the art of biomarker research in inflammatory bowel disease-associated spondyloarthritis, showing that to date it has been largely unsatisfactory. Only a few of the biomarkers that have been investigated are likely to enter the clinical practice upon further validation in independent cohorts. The research of new and innovative biomarkers for inflammatory bowel disease-associated spondyloarthritis is warranted.