Faecal calprotectin detects subclinical bowel inflammation and may predict treatment response in spondyloarthritis

Impact of biological therapy in reducing the risk of arthritis development in inflammatory bowel diseases

OBJECTIVE

Evaluate spondyloarthritis (SpA) incidence in inflammatory bowel diseases (IBD) between patients treated with biological disease-modifying antirheumatic drugs (bDMARDs) and conventional DMARDs (cDMARDs) and define risk factors associated with SpA development.

METHODS

Retrospective cohort study was conducted on patients with Crohn's disease (CD) or ulcerative colitis (UC) and divided into two cohorts: cDMARDs or bDMARDs/targeted synthetic (ts) DMARDs treated patients. Rheumatological assessment was performed in patients presenting musculoskeletal symptoms. Multivariate analysis and Kaplan-Meier curves were used to evaluate the adjusted SpA risk development.

RESULTS

507 patients were included in the study. 176 patients with CD received bDMARDs, 112 cDMARDs and 106 new SpA diagnosies were formulated. Females (OR 1.7 (95% CI 1.1 to 3), adjusted p=0.04), non-stricturing/non-penetrating phenotype (OR 2 (95% CI 1.1 to 3.4), adjusted p=0.01), psoriasis (OR 2.1 (95% CI 1 to 4.6), adjusted p=0.04) and non-infectious uveitis (OR 6.8 (95% CI 1.4 to 33.4), adjusted p=0.01) were associated with increased SpA risk development, while bDMARDs usage was protective (OR 0.4 (95% CI 0.2 to 0.8), adjusted p=0.01), statistically higher than cDMARDs throughout the entire follow-up (effect size 0.47). 98 patients with UC received b-tsDMARDs, 121 cDMARDs and 56 new SpA diagnoses were formulated. Females (OR 2.1 (95% CI 1 to 4.3), adjusted p=0.02) and psoriasis (OR 2.7 (95% CI 1 to 6.8), adjusted p=0.03) were associated with increased SpA risk development, while bDMARDs were protective for SpA development for up to 12 months of treatment compared with cDMARDs (p=0.03).

CONCLUSIONS

bDMARDs treatment had an impact in reducing SpA development and clinical associated risk factors to transition from IBD to IBD-SpA emerged.

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.

Spondyloarthritis with inflammatory bowel disease: the latest on biologic and targeted therapies

Spondyloarthritis (SpA) encompasses a heterogeneous group of chronic inflammatory diseases that can affect both axial and peripheral joints, tendons and entheses. Among the extra-articular manifestations, inflammatory bowel disease (IBD) is associated with considerable morbidity and effects on quality of life. In everyday clinical practice, treatment of these conditions requires a close collaboration between gastroenterologists and rheumatologists to enable early detection of joint and intestinal manifestations during follow-up and to choose the most effective therapeutic regimen, implementing precision medicine for each patient's subtype of SpA and IBD. The biggest issue in this field is the dearth of drugs that are approved for both diseases, as only TNF inhibitors are currently approved for the treatment of full-spectrum SpA-IBD. Janus tyrosine kinase inhibitors are among the most promising drugs for the treatment of peripheral and axial SpA, as well as for intestinal manifestations. Other therapies such as inhibitors of IL-23 and IL-17, phosphodiesterase 4 inhibitor, α4β7 integrin blockers and faecal microbiota transplantation seem to only be able to control some disease domains, or require further studies. Given the growing interest in the development of novel drugs to treat both conditions, it is important to understand the current state of the art and the unmet needs in the management of SpA-IBD.

Effectiveness of tumor necrosis factor inhibitors in children with enthesitis-related arthritis: a single-center retrospective analysis

Objective

In children with enthesitis-related arthritis (ERA), the hip and sacroiliac joint function might be impaired if not properly treated. We sought to evaluate the effectiveness of anti-tumor necrosis factor-α (TNF-α) therapy using the inflammatory indicators, Juvenile Arthritis Disease Activity Score 27 (JADAS27) and magnetic resonance imaging (MRI).

Methods

We conducted a single-center retrospective study of 134 patients with ERA. We evaluated the effect of anti-TNF therapy on the inflammatory indicators, active joint count, MRI quantitative score, and JADAS27 over 18 months. We used the Spondyloarthritis Research Consortium of Canada (SPARCC) and the Hip Inflammation MRI Scoring System (HIMRISS) scoring systems for hip and sacroiliac joints scoring.

Results

The average age of onset of children with ERA was 11.62 ± 1.95 years, and they were treated with disease-modifying antirheumatic drugs (DMARDs) combined with biologics (n = 87, 64.93%). There were no differences in HLA-B27 positivity between the biologics and non-biologics treatment groups [66 (49.25%) vs. 68 (50.75%), P > 0.05]. Children who received anti-TNF (71 received etanercept, 13 adalimumab, 2 golimumab, and 1 infliximab) therapy improved significantly. Children with ERA used DMARDs and biologics at baseline (Group A) were followed up to 18 months, and their active joint count (4.29 ± 1.99 vs. 0.76 ± 1.33, P = 0.000), JADAS27 (13.70 ± 4.80 vs. 4.53 ± 4.52, P = 0.000) and MRI quantitative scores (P = 0.001) were significantly lower than those at baseline. Some of the patients (n = 13, 9.70%) were treated with DMARDs at the onset of the disease, but did not show significant improvement (Group B). After 6-18 months of switching to anti-TNF therapy, related indicators of the children were significantly lower than at baseline and 1 month (P < 0.013). At 18 months, a total of 33 patients (n = 74, 44.59%) in Group A and 7 (n = 13, 53.85%) in Group B reached inactive state.

Conclusion

Eighteen months after diagnosis, anti-TNF therapy was found to be effective in children diagnosed with ERA. MRI is important for the early diagnosis of juvenile idiopathic arthritis. TNF-α inhibitors can significantly improve the clinical manifestations of sacroiliac joint and hip involvement in patients with ERA. Overall, the real-world study provides more evidence for precision diagnosis and treatment for other hospitals, families and patients.

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.

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.

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.

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.

Novel approaches to develop biomarkers predicting treatment responses to TNF-blockers

Introduction: Chronic inflammatory diseases (CIDs) cause significant morbidity and are a considerable burden for the patients in terms of pain, impaired function, and diminished quality of life. Important progress in CID treatment has been obtained with biological therapies, such as tumor-necrosis-factor blockers. However, more than a third of the patients fail to respond to these inhibitors and are exposed to the side effects of treatment, without the benefits. Therefore, there is a strong interest in developing tools to predict response of patients to biologics. Areas covered: The authors searched PubMed for recent studies on biomarkers for disease assessment and prediction of therapeutic responses, focusing on the effect of TNF blockers on immune responses in spondyloarthritis (SpA), and other CID, in particular rheumatoid arthritis and inflammatory bowel disease. Conclusions will be drawn about the possible development of predictive biomarkers for response to treatment. Expert opinion: No validated biomarker is currently available to predict treatment response in CID. New insight could be generated through the development of new bioinformatic modeling approaches to combine multidimensional biomarkers that explain the different genetic, immunological and environmental determinants of therapeutic responses.

The Increased Levels of Fecal Calprotectin in Children With Active Enthesitis Related Arthritis and MRI Signs of Sacroiliitis: The Results of a Single Center Cross-Sectional Exploratory Study in Juvenile Idiopathic Arthritis Patients

Enthesitis related arthritis (ERA) is a specific subtype of juvenile idiopathic arthritis (JIA), often regarded as an undifferentiated form of juvenile spondyloarthritis (jSpA). While gut is increasingly recognized as origin and/or target of inflammation in adult onset spondyloarthritis (SpA), the incidence of gut involvement in ERA patients is largely unknown. The aim of this study was to measure the concentration of fecal calprotectin (fCAL), a surrogate marker of gut inflammation, in patients with different subtypes of JIA, as well as to correlate the results with various demographic, clinical, laboratory, imaging, and treatment characteristics. The cross-sectional exploratory study involving 71 patients with ERA, other forms of JIA and children complaining musculoskeletal symptoms was therefore conducted. Along with fCAL assessment, a detailed clinical and laboratory examination was performed, including the calculation of a composite disease activity scores. Moreover, MRI of the sacroiliac joints was performed in all ERA and other patients complaining of low back pain. The median concentration of fCAL was highest in ERA patients (33.2 mg/kg, p = 0.02), with a significant difference between those with inactive and active disease (20.0 vs. 57.4, p = 0.01), as well as those with and without MRI signs of sacroiliitis (22.6 vs. 54.3, p = 0.04). The fCAL did not differ depending on the NSAID use (23 vs. 20, p = 0.18), although weak correlation was observed with the treatment duration (r = 0.25, p = 0.03). In conclusion, our findings indicate that a parallel inflammation in musculoskeletal system and gut can occur not just in adults with SpA, but in children with ERA as well.

The gut-joint axis in spondyloarthritis: immunological, microbial, and clinical insights

The strong genetic and clinical overlaps between spondyloarthritis (SpA) and inflammatory bowel disease (IBD) have placed much needed focus on the gut-joint axis of inflammation in SpA, leading to three key hypotheses that attempt to unravel this complex relationship. The arthritogenic peptide hypothesis and the aberrant cellular trafficking hypothesis have been put forth to rationalize the manner by which the innate and adaptive immune systems cooperate and converge during SpA pathogenesis. The bacterial dysbiosis hypothesis discusses how changes in the microbiome lead to architectural and immunological consequences in SpA. These theories are not mutually exclusive, but can provide an explanation as to why subclinical gut inflammation may sometimes precede joint inflammation in SpA patients, thereby implying a causal relationship. Such investigations will be important in informing therapeutic decisions which may be common to both SpA and IBD. However, these hypotheses can also offer insights for a coincident inflammatory relationship between the gut and the joint, particularly when assessing the immunological players involved. Insights from understanding how these systems might affect the gut and joint differently will be equally imperative to address where the therapeutic differences lie between the two diseases. Collectively, this knowledge has practical implications in predicting the likelihood of IBD development in SpA or presence of coincident SpA-IBD, uncovering novel therapeutic targets, and redesigning currently approved treatments. It is evident that a multidisciplinary approach between the rheumatology and gastroenterology fields cannot be ignored, when it comes to the care of SpA patients at risk of IBD or vice versa.

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.

Calprotectin in spondyloarthritis: A systematic review and meta-analysis

OBJECTIVE

There is still an unmet need for a simple and reliable biomarker for diagnosis and disease activity of spondyloarthritis. Recent studies indicated that calprotectin could act as a biomarker for spondyloarthritis. Therefore, this systematic review and meta-analysis aims to evaluate the levels of serum and fecal calprotectin in spondyloarthritis and the associations with disease activity.

METHODS

PubMed, Web of Science and Cochrane Library were comprehensively searched from inception to July 1st, 2019. The pooled standard mean differences (SMDs) were used to estimate the differences of the levels of serum and fecal calprotectin between spondyloarthritis patients and controls. Spearman correlation coefficients were used for evaluating the associations between the levels of serum and fecal calprotectin and disease activity of spondyloarthritis patients. The use of fixed-effect or random-effects model depended on heterogeneity.

RESULTS

Among 257 searched studies, 20 studies were finally included for analysis. Serum and fecal calprotectin were both significantly increased in spondyloarthritis patients compared to matched controls (SMD = 1.49, 95% CI = 0.91 to 2.08; SMD = 2.29, 95% CI = 0.25 to 4.33). The pooled correlation coefficients between serum or fecal calprotectin and CRP, ESR, BASDAI and BASFI were 0.353, 0.228, 0.225, 0.131 and 0.185, 0.163, 0.280, 0.196 respectively.

CONCLUSION

Our study indicated that serum and fecal calprotectin were significantly increased in spondyloarthritis patients, and associated with disease activity. Serum and fecal calprotectin were potential biomarkers for the diagnosis and disease activity of spondyloarthritis.

Relationship between faecal calprotectin and inflammation in peripheral joints and entheses in axial spondyloarthritis

Objectives: To compare faecal calprotectin levels according to the type of manifestation and to investigate factors associated with increases in faecal calprotectin in patients with axial spondyloarthritis (axSpA). Method: The study enrolled 190 patients fulfilling the imaging arm of the Assessment of SpondyloArthritis international Society axSpA criteria. Faecal calprotectin levels were measured in an enzyme-linked immunosorbent assay. Systemic inflammatory markers and the Ankylosing Spondylitis Disease Activity Score (ASDAS) were also assessed. Peripheral joint involvement was assessed using the 44-joint examination and Spondyloarthritis Research Consortium of Canada Enthesitis Index. Results: Of 190 patients, 34 (18%) had increased faecal calprotectin levels. These patients were more likely to have ongoing peripheral arthritis and enthesitis (p = 0.016 and 0.001, respectively). A history of psoriasis and uveitis, or current uveitis symptoms, had no bearing on faecal calprotectin levels. Faecal calprotectin levels increased along with ASDAS-C-reactive protein (CRP), and correlated with ASDAS-erythrocyte sedimentation rate (ESR) (r = 0.240, p = 0.001), ASDAS-CRP (r = 0.162, p = 0.025), ESR (r = 0.228, p = 0.002), and CRP levels (0.258, p < 0.001). Tender joint and swollen joint counts also correlated with faecal calprotectin levels (r = 0.252 and 0.205, p < 0.001 and p = 0.005, respectively). Faecal calprotectin levels were higher in patients with current peripheral symptoms (p = 0.003). Peripheral symptoms were independently associated with increased faecal calprotectin levels (odds ratio = 4.083; 95% confidence interval 1.580-10.556). Conclusions: Faecal calprotectin levels in axSpA patients were associated with disease activity. Subclinical gut inflammation (assessed by measuring faecal calprotectin) in axSpA is more closely related to peripheral joint inflammation than to axial joint inflammation.

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.

Fecal Calprotectin, CRP and Leucocytes in IBD Patients: Comparison of Biomarkers With Biopsy Results

Background

This study aimed to compare fecal calprotectin (FC) levels with other commonly used parameters as part of patient care during evaluation for inflammatory bowel disease (IBD).

Methods

We recruited adult IBD patients with ulcerative colitis (UC) and Crohn's disease (CD) and compared the results of the patient's biopsy results (i.e., inflamed versus noninflamed) for six sites (i.e., ileum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum) with concentrations of C-reactive protein (CRP), total leucocytes and fecal calprotectin (FC).

Results

We found that FC was significantly elevated in a concentration-dependent manner that correlated with the number of active inflammation sites reported in biopsy. Although CRP and leucocyte measurements trended upwards in line with inflammation reported from biopsy, the results were highly variable and highlighted poor reliability of these biomarkers for indicating IBD inflammation.

Conclusions

These results strongly suggest that FC correlates best with biopsy reports and is a superior marker than CRP and leucocytes.

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.

Fecal Calprotectin, Gut Inflammation and Spondyloarthritis

BACKGROUND

Gut inflammation is closely related to spondyloarthritis (SpA) pathophysiology. Fecal calprotectin has been used to measure the degree of gut inflammation. The phenotype of SpA may change according to studied population.

AIM

To study the fecal calprotectin levels in a sample of SpA in Brazilian patients and its relationship with epidemiological, clinical and treatment variables as well as with the macro and microscopic degree of gut inflammation.

METHODS

Eighty five SpA patients were studied for epidemiological and clinical features, functional and inflammatory indexes and fecal calprotectin levels measured using a ELISA kit. Colonoscopy with intestinal biopsies were performed in 39 of them. At time of colonoscopy a second calprotectin level was done after suspension of at least 3 weeks of used anti-inflammatory nonsteroidal drugs (NSAIDs).

RESULTS

Fecal calprotectin levels were higher in Ankylosing Spondylitis (AS) patients (p <0.0001) and in those with axial involvement (p = 0.002). No relationship was found with SpA inflammatory and functional parameters (all p = ns). After suspension of NSAIDs, a drop in fecal calprotectin levels was observed (from median levels of 215.0-76.0 μg/g; p = 0.01). In the colonoscopy, 33.3% had macroscopic signs of inflammation and these patients had higher calprotectin (p = 0.009) than others. Microscopic examination showed that all patients had lymphoplasmacytic infiltrate and eosinophilic infiltrate; epithelial erosion was present in 27.2%.

CONCLUSIONS

Patients with ankylosing spondylitis and axial forms of diseases have higher fecal calprotectin levels. Patients with all types of SpA have microscopic inflammatory changes in the gut.

Spondyloarthritis patients with and without intestinal symptoms - searching for discriminating biomarkers

Spondyloarthritis (SpA) is often complicated with subclinical gut inflammation. This study was aimed at searching for biomarkers discriminating SpA patients with and without intestinal symptoms. A group of 29 SpA patients and 33 healthy volunteers (control) were included in the study. Based on clinical evaluation, the patient cohort was subdivided into two groups: 1) SpA accompanied by various intestinal symptoms suggesting gut inflammation (group 2, n = 14) and 2) without such complications (group 1, n = 15). Serum concentrations of interleukins (IL) (IL-10, IL-17A/F, IL-22, IL-23), tumour necrosis factor (TNF), bone-homeostasis-related factors (osteoprotegerin – OPG and Dickkopf-1 – DKK-1), and the concentrations of selected gut inflammation-associated factors (intestinal fatty acid binding protein – iFABP, claudin 3 – CLDN3 and calprotectin) in samples of sera and/or urine or stool, respectively, were measured by specific ELISA. Serum concentrations of tested factors were similar in SpA patients and control. Faecal calprotectin level was higher in patients but did not discriminate between group 1 and 2. Compared to group 1, group 2 was characterized by elevated erythrocyte sedimentation rate (ESR), higher serum CLDN3 and DKK-1 levels. In SpA patients, serum DKK-1 concentrations correlated with systemic inflammation markers (R = 0.6, p < 0.01), while serum CLDN3 was found to be an independent risk factor (OR = 4.5, p = 0.021) for the occurrence of intestinal symptoms. We conclude that in SpA patients, up-regulated circulating levels of CLDN3 seem to be related to intestinal complication, while the quantity of circulating DKK-1 reflects the intensity of systemic inflammation.