Detection of Crohn Disease in Patients with Spondyloarthropathy: The SpACE Capsule Study

Arthritis complicating inflammatory bowel disease- the future is now

Fundamental advances are occurring across immune-mediated inflammatory diseases. Recent therapeutic developments include strategies to prevent rheumatoid arthritis in high-risk individuals, using baseline cellular immunophenotypes to predict response to biologics in psoriatic arthritis, and using biologics in a top-down approach for Crohn's disease. However, meaningful progress has not occurred in the management of patients with spondyloarthropathy complicating inflammatory bowel disease (IBD). Currently, the pathophysiology of IBD-related spondyloarthropathy is poorly understood; moreover, there are no accepted or disease-specific screening tools, diagnostic criteria, or licenced treatments. Current approaches to clinical care from rheumatologists and gastroenterologists largely involve the extrapolation of spondyloarthropathy and IBD clinical guidelines, respectively, despite increasing recognition of IBD-related spondyloarthropathy being its own entity, with a unique phenotype. There is an obvious contrast between spondyloarthropathy complicating IBD and the management of arthropathy complicating psoriasis, a disease area where defined diagnostic criteria and dedicated clinical trials allow clear management guidelines. We argue that the time has come for a parallel approach and dedicated focus on IBD-related spondyloarthropathy.

Comparing clinical profiles in spondyloarthritis with Crohn's disease or ulcerative colitis: insights from the ASAS-PerSpA study

Objectives

Assuming SpA manifestations may vary among patients with different inflammatory bowel disease (IBD) subtypes, we explored the clinical characteristics associated with the presence of Crohn's disease (CD) or ulcerative colitis (UC) in patients with spondyloarthritis (SpA).

Methods

We included 3152 patients of ASAS-PerSpA study diagnosed with either axial SpA or peripheral SpA, according to their treating rheumatologist. Of these, 146 (4.6%) had confirmed IBD by endoscopy and were categorized into CD or UC groups. Demographics, clinical characteristics, treatments and patient-reported outcomes were compared between the two subgroups.

Results

From 146 patients included in the current analysis, 87 (59.6%) had CD [75 (86.2%) axial SpA and 12 (13.8%) peripheral SpA], and 39 (26.7%) had UC [34 (87.2%) axial SpA and 5 (12.8%) peripheral SpA]. CD and UC groups had similar age with average of 44.9 (13.5) vs 44.0 (13.0) years, respectively, and a slight male predominance in CD (63.2%) compared with UC (51.3%). Diagnostic delay for SpA was 7.0 (6.9) years for CD and 8.8 (8.1) years for UC. Chronic back pain was the most reported symptom present in 95.4% of CD patients and 89.7% of UC patients. Both groups had similar musculoskeletal phenotyping, with higher frequency of psoriasis (15.4%) and uveitis 28.2% in UC; and higher tendency to be HLA-B27 positive in CD (51.9% in CD vs.s 39.4% in UC).

Conclusion

In our analysis patients with SpA and concurrent CD or UC had mainly similar musculoskeletal phenotypes. However, they differ slightly in extra-musculoskeletal manifestations and HLA-B27 prevalence.

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.

Biologic Treatment Modification Efficacy in Concurrent Inflammatory Bowel Disease and Ankylosing Spondylitis: A Retrospective Cohort Study at a Single Tertiary Center

BACKGROUND

The link between ankylosing spondylitis (AS) and inflammatory bowel disease (IBD) is well-established, with concurrent prevalence estimates ranging from 5-10%. However, there are still significant gaps in our understanding, and a comprehensive treatment guideline for these co-diagnosed patients has yet to be established. Our objective was to explore patterns of treatment alterations following the diagnosis of AS in patients previously diagnosed with IBD, and vice versa. Additionally, we sought to determine how these modifications influence clinical outcomes in both conditions.

METHODS

This retrospective data-based cohort study included patients with coexisting IBD and AS that were diagnosed between the years 2009-2022 and were followed by the gastroenterology and the rheumatology units of the Sheba Medical Center, Israel. The data were extracted from the electronic health record and included demographic information, medication history, treatment modification at the time of second diagnosis, and the characteristics and activity of both IBD and AS at the index time and at the 3-month mark.

RESULTS

The study included a total of 68 patients, with a male predominance (40 patients, 59%). The median age was 43 years (IQR 31-55) and 78% had Crohn's disease (CD). The median duration between the diagnosis of the first disease to the second one was 4 years (IQR 1-9.5). A significant proportion of patients (85%) underwent treatment modification at their second diagnosis. Out of the total cohort, 28% initiated biological therapy, 17.6% switched their biologic regimen, and 16.2% discontinued NSAIDS. Patients who underwent biologic modifications at time of the second diagnosis (the initiation/switch/augmentation of a concurrent regimen) experienced significantly higher rates of clinical improvement in either IBD or AS at the 90-day follow-up compared to patients who did not (68% vs. 32%, p = 0.004), and biologic modification was found to be an independent predictor for clinical improvement (OR 3.69, CI 1.08-12.58, p = 0.037).

CONCLUSIONS

Our findings suggest that biologic therapy modification at the time of the second diagnosis was associated with a higher rate of improvement in AS/IBD at the 90-day follow-up.

Video Capsule Endoscopy can Identify Occult Luminal Crohn's Disease in Patients with Isolated Perianal Fistulas

BACKGROUND

Accurate tools to distinguish Crohn's disease [CD] from cryptoglandular disease in patients with perianal fistulas without detectable luminal inflammation on ileocolonoscopy and abdominal enterography (isolated perianal fistulas [IPF]) are lacking. We assessed the ability of video capsule endoscopy [VCE] to detect luminal inflammation in patients with IPF.

METHODS

We studied consecutive adults [>17 years] with IPF who were evaluated by VCE after a negative ileocolonoscopy and abdominal enterography between 2013 and 2022. We defined luminal CD by VCE as diffuse erythema, three or more aphthous ulcers, or a Lewis score greater than 135. We compared rates of intestinal inflammation in this cohort with age- and sex-matched controls without perianal fistulas, who underwent VCE for other indications. We excluded persons with pre-existing inflammatory bowel disease [IBD] and exposure to non-steroidal anti-inflammatory drugs or immunosuppressive treatments.

RESULTS

A total of 45 patients with IPF underwent VCE without complications. Twelve patients [26%] met our definition of luminal CD. Luminal CD was more common in patients with IPF than in controls [26% vs 3%; p <0.01]. Among patients with IPF, male sex (OR [odds ratio], 9.2; 95% confidence interval [CI] [1.1-79.4]), smoking (OR, 4.5; 95% CI [0.9-21.2]), abscess (OR, 6.3; 95% CI [1.5-26.8]), rectal enhancement on magnetic resonance imaging [MRI] (OR, 9.0; 95% CI [0.8-99.3]), and positive antimicrobial serology (OR, 7.1; 95% CI, [0.7-70.0]) were more common in those with a positive VCE study.

CONCLUSIONS

VCE detected small intestinal inflammation suggestive of luminal CD in approximately one-quarter of patients with IPF. Larger studies are required to validate these findings.

Sterile triggers drive joint inflammation in TNF- and IL-1β-dependent mouse arthritis models

Arthritis is the most common extra-intestinal complication in inflammatory bowel disease (IBD). Conversely, arthritis patients are at risk for developing IBD and often display subclinical gut inflammation. These observations suggest a shared disease etiology, commonly termed "the gut-joint-axis." The clinical association between gut and joint inflammation is further supported by the success of common therapeutic strategies and microbiota dysbiosis in both conditions. Most data, however, support a correlative relationship between gut and joint inflammation, while causative evidence is lacking. Using two independent transgenic mouse arthritis models, either TNF- or IL-1β dependent, we demonstrate that arthritis develops independently of the microbiota and intestinal inflammation, since both lines develop full-blown articular inflammation under germ-free conditions. In contrast, TNF-driven gut inflammation is fully rescued in germ-free conditions, indicating that the microbiota is driving TNF-induced gut inflammation. Together, our study demonstrates that although common inflammatory pathways may drive both gut and joint inflammation, the molecular triggers initiating such pathways are distinct in these tissues.

SpA plus IBD or IBD plus SpA: Does commutative property apply?

The term spondyloarthritis (SpA) encompasses a group of interrelated disorders characterised by the involvement of the musculoskeletal system as well as extra-articular manifestations like acute anterior uveitis, psoriasis and inflammatory bowel diseases (IBD). Likewise, IBD may present with various extra-intestinal manifestations among which those involving the musculoskeletal system, namely peripheral and axial SpA are the most common. The identification of patients with both SpA and IBD is of paramount importance in clinical practice since the coexistence of these two entities has been associated with great disability and decreased quality of life. In order to achieve an early diagnosis of IBD-SpA it is instrumental that rheumatologists seek for gastrointestinal symptoms in SpA patients and likewise that gastroenterologists seek for inflammatory musculoskeletal symptoms in patients with IBD. This narrative review aims at critically appraising the available evidence about SpA occurring in IBD patients versus IBD occurring in patients with SpA and at highlighting similarities and differences between the two scenarios.

The Interleukine-17 Cytokine Family: Role in Development and Progression of Spondyloarthritis, Current and Potential Therapeutic Inhibitors

Spondyloarthritis (SpA) encompasses a group of chronic inflammatory rheumatic diseases with a predilection for the spinal and sacroiliac joints, which include axial spondyloarthritis, psoriatic arthritis, reactive arthritis, arthritis associated with chronic inflammatory bowel disease, and undifferentiated spondyloarthritis. The prevalence of SpA in the population varies from 0.5 to 2%, most commonly affecting young people. Spondyloarthritis pathogenesis is related to the hyperproduction of proinflammatory cytokines (TNFα, IL-17A, IL-23, etc.). IL-17A plays a key role in the pathogenesis of spondyloarthritis (inflammation maintenance, syndesmophites formation and radiographic progression, enthesites and anterior uveitis development, etc.). Targeted anti-IL17 therapies have established themselves as the most efficient therapies in SpA treatment. The present review summarizes literature data on the role of the IL-17 family in the pathogenesis of SpA and analyzes existing therapeutic strategies for IL-17 suppression with monoclonal antibodies and Janus kinase inhibitors. We also consider alternative targeted strategies, such as the use of other small-molecule inhibitors, therapeutic nucleic acids, or affibodies. We discuss advantages and pitfalls of these approaches and the future prospects of each method.

Fecal calprotectin as a biomarker of microscopic bowel inflammation in patients with spondyloarthritis

AIM

Microscopic bowel inflammation is present in up to 60% of all patients with spondyloarthritis (SpA) and appears to be associated with more severe joint disease and a higher risk of developing inflammatory bowel disease (IBD). This study aimed to determine the utility of fecal calprotectin (fCAL) in evaluating endoscopic and histological bowel inflammation in SpA patients.

METHODS

Ileocolonoscopies with biopsies and fCAL measurements were performed in 65 patients with SpA.

RESULTS

In 47 (72.3%) patients, the fCAL levels were higher than 50 μg/g, whereas in 20 (30.7%), these levels were greater than 250 μg/g. A total of 38 (58.5%) patients presented with microscopic bowel inflammation, and 13 (20%) presented with signs of endoscopic inflammation. fCAL levels were significantly higher in patients with microscopic bowel inflammation than in those without inflammatory findings (P < .001); additionally, these levels were slightly higher in patients with endoscopic signs of bowel inflammation (P = .053). A fCAL cutoff value of 96 μg/g predicted histological bowel inflammation with 73% sensitivity and 67% specificity. No statistically significant difference was observed in the fCAL levels between patients who had been treated or not treated with nonsteroidal anti-inflammatory drugs (NSAIDs).

CONCLUSION

Our findings confirm a high prevalence of microscopic bowel inflammation in SpA patients, regardless of the use of NSAIDs. The evaluation of fCAL levels proved to be useful in the identification of microscopic inflammation and could help in the more judicious indication of ileocolonoscopy. These results support the use of fCAL for the evaluation of microscopic bowel inflammation in SpA patients.

Strategies to Distinguish Perianal Fistulas Related to Crohn's Disease From Cryptoglandular Disease: Systematic Review With Meta-Analysis

BACKGROUND

Management of perianal fistulas differs based on fistula type. We aimed to assess the ability of diagnostic strategies to differentiate between Crohn's disease (CD) and cryptoglandular disease (CGD) in patients with perianal fistulas.

METHODS

We performed a diagnostic accuracy systematic review and meta-analysis. A systematic search of electronic databases was performed from inception through February 2021 for studies assessing a diagnostic test's ability to distinguish fistula types. We calculated weighted summary estimates with 95% confidence intervals for sensitivity and specificity by bivariate analysis, using fixed effects models when data were available from 2 or more studies. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess study quality.

RESULTS

Twenty-one studies were identified and included clinical symptoms (2 studies; n=154), magnetic resonance imaging (MRI) characteristics (3 studies; n=296), ultrasound characteristics (7 studies; n=1003), video capsule endoscopy (2 studies; n=44), fecal calprotectin (1 study; n=56), and various biomarkers (8 studies; n=440). MRI and ultrasound characteristics had the most robust data. Rectal inflammation, multiple-branched fistula tracts, and abscesses on pelvic MRI and the Crohn's ultrasound fistula sign, fistula debris, and bifurcated fistulas on pelvic ultrasonography had high specificity (range, 80%-95% vs 89%-96%) but poor sensitivity (range, 17%-37% vs 31%-63%), respectively. Fourteen of 21 studies had risk of bias on at least 1 of the Quality Assessment of Diagnostic Accuracy Studies domains.

CONCLUSIONS

Limited high-quality evidence suggest that imaging characteristics may help discriminate CD from CGD in patients with perianal fistulas. Larger, prospective studies are needed to confirm these findings and to evaluate if combining multiple diagnostic tests can improve diagnostic sensitivity.

Deep Insight into the Role of MIF in Spondyloarthritis

PURPOSE OF REVIEW

Pathological roles of macrophage migration inhibitory factor (MIF) have recently been demonstrated in spondyloarthritis (SpA) preclinical models, identifying MIF as a new treatment target for SpA. However, the specific contribution of MIF and therapeutic potential of MIF-targeted therapies to various tissue types affected by SpA are not well delineated.

RECENT FINDINGS

MIF and its cognate receptor CD74 are extensively involved in the pathogenesis of SpA including inflammation in the spine, joint, eyes, skin, and gut. The majority of the current evidence has consistently shown that MIF drives the inflammation in these distinct anatomical sites. In preclinical models, genetic deletion or blockade of MIF reduces the severity of inflammation. Although MIF is generally an upstream cytokine which regulates downstream effector cytokines, MIF also intensifies type 3 immunity by promoting helper T 17 (Th17) plasticity. MIF- or CD74-targeted therapies have also reported to be well tolerated in clinical trials for other diseases. Recent findings suggest that MIF-CD74 axis is a new therapeutic target for SpA to improve various clinical features. Clinical trials for MIF- or CD74-targeted therapies for SpA patients are warranted.

Gut dysbiosis associated with worse disease activity and physical function in axial spondyloarthritis

Background

Based on clinical and genetic associations, axial spondyloarthritis (axSpA) and inflammatory bowel disease (IBD) are suspected to have a linked pathogenesis. Gut dysbiosis, intrinsic to IBD, has also been observed in axSpA. It is, however, not established to what degree gut dysbiosis is associated with axSpA disease severity.

The objective of this study was to compare gut dysbiosis frequency between controls, non-radiographic axial spondyloarthritis (nr-axSpA), and ankylosing spondylitis (AS) patients and investigate whether gut dysbiosis is cross-sectionally associated with axSpA disease activity, physical function, mobility, or pain.

Methods

Gut dysbiosis was assessed by 16SrRNA analysis of feces from 44/88 nr-axSpA/AS patients (ASAS/mNY criteria) without inflammatory bowel disease (IBD) and 46 controls without IBD or rheumatic disease. The GA-map™ Dysbiosis Test was used, grading gut microbiota aberrations on a 1-5 scale, where ≥3 denotes dysbiosis. Proportions with dysbiosis were compared between the groups. Furthermore, standard axSpA measures of disease activity, function, mobility, and pain were compared between patients (nr-axSpA and AS combined) with and without dysbiosis, univariately, and adjusted for relevant confounders (ANCOVA).

Results

Gut dysbiosis was more frequent in AS than controls (36% versus 17%, p=0.023), while nr-axSpA (25% dysbiosis) did not differ significantly from either AS or controls. Univariately, most axSpA measures were significantly worse in patients with dysbiosis versus those without: ASDAS-CRP between-group difference 0.6 (95% CI 0.2–0.9); BASDAI 1.6 (0.8–2.4); evaluator’s global disease activity assessment (Likert scale 0–4) 0.3 (0.1–0.5), BASFI 1.5 (0.6–2.4), and VAS pain (cm) 1.3 (0.4–2.2). Differences remained significant after adjustment for demographics, lifestyle factors, treatments, gut inflammation (fecal calprotectin ≥50 mg/kg), and gut symptoms, except for VAS pain. BASMI and CRP were not associated with dysbiosis.

Conclusion

Gut dysbiosis, more frequent in AS patients than controls, is associated with worse axSpA disease activity and physical function, seemingly irrespective of both gut inflammation and treatments. This provides further evidence for an important link between disturbances in gastrointestinal homeostasis and axSpA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02733-w.

The clinical utility of faecal calprotectin in patients with differentiated and undifferentiated spondyloarthritis: Relevance and clinical implications

OBJECTIVES

There is cumulative evidence in the literature supporting a potential role of faecal calprotectin (FCP) as a biomarker for gut inflammation in spondyloarthritis (SpA). However its relevance in undifferentiated SpA (USpA) is still uncertain. The aim of the current study is to assess the diagnostic significance of FCP levels in patients with differentiated and undifferentiated SpA.

MATERIAL AND METHODS

A total of 52 differentiated SpA, 33 USpA and 50 controls could be included. For all patients, clinical evaluation, routine laboratory investigations, FCP levels, and occult blood in stool were performed. When indicated imaging and/or endoscopies were performed.

RESULTS

The differentiated SpA patients were 12 (23.1%) with ankylosing spondylitis, 21 (40.4%) with psoriatic arthritis, 13 (25%) with ulcerative colitis, 5 (9.6%) with Crohn's disease (CD) and one (1.9%) with reactive arthritis. The mean FCP level in 85 patients correlated with CRP and ESR. Within the SpA group ulcerative colitis and Crohn's disease patients had increased FCP levels compared to other SpA subgroups and USpA patients (p<0.001). The mean FCP levelwas significantly higher in the SpA patients compared to USpA and controls (p<0.001).

CONCLUSIONS

Elevated FCP levels may identify patients who are most likely to have SpA already in the unclassified phase of the disease. Further studies in different series of patients are needed to evaluate the potential diagnostic and prognostic roles of FCP in both differentiated and undifferentiated phases of the disease.

Elevated Serum D-Dimer May Reflect the Presence of Gut Inflammation in Spondyloarthritis

Background

To investigate the association of D-dimer with gut inflammation in spondyloarthritis (SpA).

Methods

Sixty-five patients with SpA and 70 healthy controls were included. Demographic, clinical, and laboratory parameters were collected. The differences of clinical and laboratory parameters were compared between patients with SpA and healthy controls, and between patients with SpA, with and without gut inflammation. The associations of D-dimer with laboratory data were analyzed. The predictive value of D-dimer was obtained by a receiver operator characteristic (ROC) curve analysis. The independent risk factors for gut inflammation in SpA were investigated by binary logistic regression analysis.

Results

Patients with SpA had higher D-dimer than healthy controls (P = 0.016). D-dimer was positively correlated with platelet (PLT), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), and negatively correlated with hemoglobin (Hb). Besides, significant differences were observed in D-dimer between SpA patients with and without gut inflammation (P < 0.001). Furthermore, SpA patients with gut inflammation were more likely to have peripheral joint involvement than those without gut inflammation (P < 0.001). The AUC of D-dimer was 0.865 at cut-off value of 0.29 mg/L, with a sensitivity of 82.6%, and a specificity of 81%. Elevated D-dimer (OR = 15.451, 95% CI: 3.030–78.780, P = 0.001) was independently associated with gut inflammation in SpA.

Conclusion

D-dimer may be a potential biomarker for identifying SpA patients with gut inflammation.

Inflammatory bowel disease manifestations in spondyloarthritis: considerations for the clinician

INTRODUCTION

Spondyloarthropathies (SpA) are a group of inflammatory arthritis that can involve the spine and/or peripheral joints. Extra-articular manifestations, such as inflammatory bowel disease (IBD), are frequently observed within the clinical manifestations of SpA and are part of the SpA classification criteria. Evidence of IBD is observed in about 6-7% of SpA patients, and a silent, microscopic gut inflammation, could be present in up to 50% of patients. From a pathogenetic point of view, dysregulated microbiome and migration of T lymphocytes and other cells from gut to the joint ('gut-joint' axis) has been recognized, in the context of a common genetic background.

AREAS COVERED

The aim of this paper is to narratively review the recent evidences on the epidemiology, classification, clinical findings, pathogenesis, diagnosis, and treatment of IBD in patients with SpA and to provide advices for both rheumatologist and gastroenterologist in the management of IBD in SpA.

EXPERT OPINION

IBD manifestations in SpA frequently increase the burden of the disease and represent a clinical challenge, especially for the diagnosis, assessment, and treatment of patients affected by those conditions. New treatment strategies targeting both articular and intestinal manifestations are now available and may lead to a better outcome.

Managing Psoriatic Arthritis With Inflammatory Bowel Disease and/or Uveitis

Psoriatic arthritis (PsA) is a chronic inflammatory disease that presents with psoriasis (PsO), peripheral and axial arthropathy. The heterogeneity of disease presentation leads to the term "psoriatic disease (PsD)" which is thought to better encompass the range of clinical manifestations. PsA is associated with several comorbidities such as cardiovascular diseases, metabolic syndrome and other extra-articular manifestations including uveitis, and inflammatory bowel disease (IBD). While novel therapeutics are being developed following advances in our understanding of the pathogenesis of the disease, the diverse combinations of PsA with its various comorbidities still pose a clinical challenge in managing patients with PsA. This article reviews our current understanding of the pathogenesis of PsA and how various pathways in the pathogenesis lead to the two comorbid extra-articular manifestations - uveitis and IBD. We also review current evidence of treatment strategies in managing patients with PsA with comorbidities of uveitis and/or IBD.

Diagnostic Accuracy of Fecal Calprotectin for the Detection of Small Bowel Crohn's Disease through Capsule Endoscopy: An Updated Meta-Analysis and Systematic Review

Background/Aims

The diagnosis of small bowel Crohn's disease with negative ileocolonoscopic findings has been challenging. Fecal calprotectin (FC) has been used to detect colonic inflammation, but its efficacy for detecting small bowel inflammation is less established. We performed an updated meta-analysis to evaluate the diagnostic accuracy of FC to detect active small bowel inflammation observed during capsule endoscopy.

Methods

We conducted a systematic literature search for studies that evaluated the correlation between small bowel inflammation and FC in patients with suspected/established Crohn's disease. We calculated the pooled sensitivity, specificity, and diagnostic odds ratios (DORs) and constructed hierarchical summary receiver operating characteristic curves for FC cutoffs of 50, 100, and 200 μg/g.

Results

Fourteen studies were eligible for the final analysis. The DORs of all FC cutoffs were significant. The highest DOR was observed at 100 μg/g (sensitivity, 0.73; specificity, 0.73; and DOR, 7.89) and was suggested as the optimal diagnostic cutoff. If we analyzed only studies that included patients with suspected Crohn's disease, the DOR was 8.96. If we analyzed only studies that included patients with a Lewis score ≥135 as a diagnostic criterion for active disease, the DOR was 10.90.

Conclusions

FC has significant diagnostic accuracy for detecting small bowel inflammation, and an FC cutoff of 100 μg/g can be used as a tool to screen for small bowel Crohn's disease.

The Clinical Utility of Faecal Calprotectin in Patients with Differentiated and Undifferentiated Spondyloarthritis: Relevance and Clinical Implications

OBJECTIVES

There is cumulative evidence in the literature supporting a potential role of faecal calprotectin (FCP) as a biomarker for gut inflammation in spondyloarthritis (SpA). However its relevance in undifferentiated SpA (USpA) is still uncertain. The aim of the current study is to assess the diagnostic significance of FCP levels in patients with differentiated and undifferentiated SpA.

MATERIAL AND METHODS

A total of 52 differentiated SpA, 33 USpA and 50 controls could be included. For all patients, clinical evaluation, routine laboratory investigations, FCP levels, and occult blood in stool were performed. When indicated imaging and/or endoscopies were performed.

RESULTS

The differentiated SpA patients were 12 (23.1%) with ankylosing spondylitis, 21 (40.4%) with psoriatic arthritis, 13 (25%) with ulcerative colitis, 5 (9.6%) with Crohn's disease (CD) and one (1.9%) with reactive arthritis. The mean FCP level in 85 patients correlated with CRP and ESR. Within the SpA group ulcerative colitis and Crohn's disease patients had increased FCP levels compared to other SpA subgroups and USpA patients (p<0.001). The mean FCP levelwas significantly higher in the SpA patients compared to USpA and controls (p<0.001).

CONCLUSIONS

Elevated FCP levels may identify patients who are most likely to have SpA already in the unclassified phase of the disease. Further studies in different series of patients are needed to evaluate the potential diagnostic and prognostic roles of FCP in both differentiated and undifferentiated phases of the disease.

IBD considerations in spondyloarthritis

Spondyloarthritis (SpA) may be regarded a family of auto-inflammatory conditions with inflammation focused on the joints. These form part of a wider family of immune-mediated inflammatory diseases, which include inflammatory bowel diseases (IBD). These conditions share common elements of pathophysiology and it is perhaps unsurprising, therefore, that individuals with SpA frequently manifest gastrointestinal inflammation, to which the physician managing the patient with SpA must be alert. In this article, we review the shared epidemiology and pathophysiology of these conditions, before discussing approaches to diagnosis and management of inflammatory gastrointestinal pathology in patients seen in rheumatology clinics. In particular, we discuss the difference between non-specific gastrointestinal inflammation commonly described in this patient group and the more specific diagnosis of Crohn's disease or ulcerative colitis. We describe the appropriate diagnostic workup for patients suspected of having IBD. In addition, we discuss how a diagnosis of IBD can inform treatment selection, highlighting important differences in treatment choice, drug dosing, monitoring and drug safety for this particular comorbid patient population.

Faecal Calprotectin for the Diagnosis of Bowel Inflammation in Patients With Rheumatological Diseases: A Systematic Review

BACKGROUND AND AIMS

Endoscopic and histological gut inflammation are present in half of patients with ankylosing spondylitis [AS] or spondyloarthritis [SpA]. We performed a systematic literature review on the use of faecal calprotectin [FC] in patients with rheumatic diseases.

METHODS

Searches of the PubMed, Web of Science, and Cochrane Library databases were performed up to September 2019 to identify all studies including adult patients with confirmed diagnosis of SpA or AS.

RESULTS

Seven studies met the inclusion criteria: six prospective observational studies and one retrospective observational study. Study populations consisted of SpA patients in four studies and AS patients in three studies. In six studies, an ELISA test was used for FC levels and in one case, a semi-quantitative assay was adopted. In all included studies, patients with SpA or AS had elevated FC levels, ranging from 21.2% to 70.7% of patients. In six studies, patients with increased FC levels had macroscopic mucosal inflammation, ranging from 11% to 80% of cases. Four studies highlighted the presence of microscopic alterations in patients with high FC levels, ranging from 41.7% to 100% of patients. An FC cut-off level predicting the inflammatory bowel disease [IBD] occurrence was found in two studies: 266 mg/kg and 132 mg/kg, with sensitivity and specificity of 100%, 78.7% and 66.7%, 76.9%, respectively.

CONCLUSIONS

Faecal calprotectin is a useful and non-invasive marker to predict IBD in patients with SpA or AS. Gut histological and macroscopic mucosal inflammation were found in up to 100% and 80% of rheumatological patients with increased FC levels.

Approach to the Patient with Axial Spondyloarthritis and Suspected Inflammatory Bowel Disease

To adequately and efficiently evaluate patients with gastrointestinal symptoms in the context of axial spondyloarthritis can be difficult, considering that many of these patients suffer from chronic pain, present high inflammatory parameters, and use drugs with possible gastrointestinal adverse effects. In addition, the immunosuppressive treatments that these patients can receive make it necessary to always consider infections within the differential diagnoses of inflammatory bowel disease. In this article, we propose a practical approach to patients diagnosed with axial spondyloarthritis and suspected inflammatory bowel disease.

Deep learning algorithms for automated detection of Crohn's disease ulcers by video capsule endoscopy

BACKGROUND AND AIMS

The aim of our study was to develop and evaluate a deep learning algorithm for the automated detection of small-bowel ulcers in Crohn's disease (CD) on capsule endoscopy (CE) images of individual patients.

METHODS

We retrospectively collected CE images of known CD patients and control subjects. Each image was labeled by an expert gastroenterologist as either normal mucosa or containing mucosal ulcers. A convolutional neural network was trained to classify images into either normal mucosa or mucosal ulcers. First, we trained the network on 5-fold randomly split images (each fold with 80% training images and 20% images testing). We then conducted 10 experiments in which images from n - 1 patients were used to train a network and images from a different individual patient were used to test the network. Results of the networks were compared for randomly split images and for individual patients. Area under the curves (AUCs) and accuracies were computed for each individual network.

RESULTS

Overall, our dataset included 17,640 CE images from 49 patients: 7391 images with mucosal ulcers and 10,249 images of normal mucosa. For randomly split images results were excellent, with AUCs of .99 and accuracies ranging from 95.4% to 96.7%. For individual patient-level experiments, the AUCs were also excellent (.94-.99).

CONCLUSIONS

Deep learning technology provides accurate and fast automated detection of mucosal ulcers on CE images. Individual patient-level analysis provided high and consistent diagnostic accuracy with shortened reading time; in the future, deep learning algorithms may augment and facilitate CE reading.

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.

Inflammatory bowel diseases and spondyloarthropathies: From pathogenesis to treatment

Spondyloarthropathies (SpA) include many different forms of inflammatory arthritis and can affect the spine (axial SpA) and/or peripheral joints (peripheral SpA) with Ankylosing spondylitis (AS) being the prototype of the former. Extra-articular manifestations, like uveitis, psoriasis and inflammatory bowel disease (IBD) are frequently observed in the setting of SpA and are, in fact, part of the SpA classification criteria. Bowel involvement seems to be the most common of these manifestations. Clinically evident IBD is observed in 6%-14% of AS patients, which is significantly more frequent compared to the general population. Besides, it seems that silent microscopic gut inflammation, is evident in around 60% in AS patients. Interestingly, occurrence of IBD has been associated with AS disease activity. For peripheral SpA, two different forms have been proposed with diverse characteristics. Of note, SpA (axial or peripheral) is more commonly observed in Crohn's disease than in ulcerative colitis. The common pathogenetic mechanisms that explain the link between IBD and SpA are still ill-defined. The role of dysregulated microbiome along with migration of T lymphocytes and other cells from gut to the joint ("gut-joint" axis) has been recognized, in the context of a genetic background including associations with alleles inside or outside the human leukocyte antigen system. Various therapeutic modalities are available with monoclonal antibodies against tumour necrosis factor, interleukin-23 and interleukin-17, being the most effective. Both gastroenterologists and rheumatologists should be alert to identify the co-existence of these conditions and ideally follow-up these patients in combined clinics.

Biomarkers for Diagnosis of Axial Spondyloarthritis, Disease Activity, Prognosis, and Prediction of Response to Therapy

There exists a major unmet need for biomarkers that can identify axial spondyloarthritis (axSpA) early after disease onset because of the availability of highly effective therapies. Several recent reports have examined the autoantibody response in patients with axSpA through the use of protein microarrays and protein-protein interactions although diagnostic performance of biomarkers identified to date has been inadequate. An example of such a biomarker is protein phosphatase magnesium-dependent 1A. Antibodies to the human leukocyte antigen class II-associated invariant chain peptide (anti-CD74) are candidate diagnostic biomarkers but sensitivity declines with increasing duration of disease. Metabolomic studies have employed nuclear magnetic resonance (NMR) spectrometry to identify disease-specific metabolites related to fat metabolism and intestinal microbial metabolism. A second major unmet need exists for biomarkers of disease activity that have superiority over standard C-reactive protein assessment and reflect MRI inflammation in the axial spine. Several biomarkers reflecting inflammation (calprotectin), angiogenesis (vasoactive endothelial growth factor), and connective tissue turnover (C2M, C3M, and citrullinated metalloproteinase degraded fragment of vimentin) have recently been shown to reflect disease activity when compared with clinical outcomes but comparisons with MRI inflammation are very limited. With increasing availability of highly effective but costly therapies, a third unmet need is biomarkers that can predict response to therapies with different mechanisms of action and are superior to C-reactive protein. Calprotectin is currently the only candidate. Although there are as yet no proven therapies for preventing progression of disease there is an unmet need for biomarkers of prognosis that are more responsive than radiography. Aside from CRP no consistent candidates have emerged. Future studies will need to be prospective, include consecutive patients presenting with undiagnosed back pain, and use more reliable and objective endpoints such as MRI inflammation. Moreover, it has become evident that targeted biomarker studies have not been successful in identifying clinically useful biomarkers and technologies that can simultaneously assess “multiomic” markers will need to be analyzed for future advances. These include more sophisticated metabolomic profiling and universal metabolome-standard (UMS) methodology, next generation RNA sequencing, and affinity-based quantitative proteomics based on the use of nucleic acid binders such as the aptamer-based SOMAscan assay.