Clinically silent inflammatory gut lesions in undifferentiated spondyloarthropathies

Prevalence and Progression of Incidental Terminal Ileitis on Non-diagnostic Colonoscopy: A Systematic Review and Meta-analysis

BACKGROUND

Incidentally diagnosed terminal ileitis [IDTI] has been reported among asymptomatic persons undergoing non-diagnostic colonoscopy. The purpose of our study was to determine the prevalence and long-term outcomes of asymptomatic terminal ileitis.

METHODS

We performed a systematic review using three biomedical databases [Medline, Embase, and Web of Science] and relevant scientific meeting abstracts. We identified observational studies that reported the prevalence of IDTI in adults undergoing screening or polyp surveillance colonoscopy and/or the long-term outcomes of such lesions. A random-effects meta-analysis was conducted to determine the pooled prevalence rate of IDTI. The progression of IDTI to overt Crohn's disease [CD] was also described.

RESULTS

Of 2388 eligible studies, 1784 were screened after excluding duplicates, 84 were reviewed in full text, and 14 studies were eligible for inclusion. Seven studies reported the prevalence of IDTI in 44 398 persons undergoing non-diagnostic colonoscopy, six studies reported follow-up data, and one study reported both types of data. The pooled prevalence rate of IDTI was 1.6% (95% confidence interval [CI] 0.1-21.8%) with significant heterogeneity [I2 = 99.7]. Among patients who had undergone non-diagnostic colonoscopy and had follow-up data [range 13-84 months reported in five studies], progression to overt CD was rare.

CONCLUSIONS

IDTI is not uncommon on non-diagnostic colonoscopies. Based on limited data, the rate of its progression to overt CD seems low, and watchful waiting is likely a reasonable strategy. Further long-term follow-up studies are needed to inform the natural history of incidental terminal ileitis, factors that predict progression to CD, and therapeutic implications.

Lipocalin 2 links inflammation and ankylosis in the clinical overlap of inflammatory bowel disease (IBD) and ankylosing spondylitis (AS)

Background

Little is known about the mechanisms underlying the clinical overlap between gut inflammation and joint ankylosis, as exemplified by the concurrence of inflammatory bowel diseases (IBD) and ankylosing spondylitis (AS). As dysbiosis may serve as a common contributor, the anti-microbial pleiotropic factor lipocalin 2 could be a potential mediator due to its roles in inflammation and bone homeostasis.

Methods

Baseline colonic pathology was conducted in the ank/ank mouse model. Serum lipocalin 2 was analyzed by ELISA, in ank/ank mutants versus C3FeB6-A/A^w-jwt/wt, in patients with concurrent AS-IBD, AS alone, IBD alone, or mechanical back pain, and in healthy controls. In the ank/ank mouse model, the expression of nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) was examined by real-time PCR. Intraperitoneal injection was done with the PPARγ agonist rosiglitazone or antagonist bisphenol A diglycidyl ether for four consecutive days. Serum levels of lipocalin 2 were examined on the sixth day.

Results

This study showed that the ank/ank mice with fully fused spines had concurrent colonic inflammation. By first using the ank/ank mouse model with progressive ankylosis and subclinical colonic inflammation, confirmed in patients with concurrent AS and IBD, elevated circulating lipocalin 2 levels were associated with the coexisting ankylosis and gut inflammation. The intracellular pathway of lipocalin 2 was further investigated with the ank/ank mouse model involving PPARγ. Colonic expression of PPARγ was negatively associated with the degree of gut inflammation. The PPARγ agonist rosiglitazone treatment significantly upregulated the serum levels of lipocalin 2, suggesting a potential regulatory role of PPARγ in the aberrant expression of lipocalin 2.

Conclusions

In summary, lipocalin 2 modulated by PPARγ could be a potential pathway involved in concurrent inflammation and ankylosis in AS and IBD.

Gastrointestinal hypoalgesia in inflammatory bowel disease

Background:

Pain perception is critical for detection of noxious bodily insults. Gastrointestinal hypoalgesia in inflammatory bowel disease (IBD) is a poorly understood phenomenon previously linked to poor patient outcomes. We aimed to evaluate the risk factors associated with this condition and to discern characteristics that might differentiate these patients from pain-free quiescent counterparts.

Methods:

We performed a retrospective analysis using an IBD natural history registry based in a single tertiary care referral center. We compared demographic and clinical features in 3 patient cohorts defined using data from simultaneous pain surveys and ileocolonoscopy: a) active IBD without pain (hypoalgesic IBD); b) active IBD with pain; and c) inactive IBD without pain.

Results:

One hundred fifty-three IBD patients had active disease and 43 (28.1%) exhibited hypoalgesia. Hypoalgesic IBD patients were more likely to develop non-perianal fistulae (P=0.03). On logistic regression analysis, hypoalgesic IBD was independently associated with male sex, advancing age and mesalamine use, and inversely associated with anxious/depressed state and opiate use. Hypoalgesic IBD patients were demographically and clinically similar to the pain-free quiescent IBD cohort (n=59). Platelet count and C-reactive protein were more likely to be pathologically elevated in hypoalgesic IBD (P=0.03), though >25% did not exhibit elevated inflammatory markers.

Conclusions:

Hypoalgesia is common in IBD, particularly in male and older individuals, and is associated with an increased incidence of fistulae and corticosteroid use. Novel noninvasive diagnostic tools are needed to screen for this population, as inflammatory markers are not always elevated.

The colon and terminal ileum in patients with ankylosing spondylitis and controls in Bangladesh: a macroscopic and microscopic study

OBJECTIVE

Little is known about gut lesions in AS patients in a developing country, such as Bangladesh.

METHODS

Full colonoscopy, including the terminal ileum, was performed in 60 AS patients and 20 controls, without diarrhoea, to study macroscopic and microscopic lesions.

RESULTS

In the colon, in 60 AS patients 17 macroscopic lesions were found, of which 11 were in the rectum; only one lesion was found in 20 controls. The prevalence of microscopic lesions in the ascending colon, sigmoid colon and rectum was 51, 44 and 50 in patients, respectively, and 13, 9 and 8 in controls. In the terminal ileum, macroscopic and microscopic lesions were seen in 21/56 and 43/56 AS patients, respectively, and in 1/20 and 9/20 controls. In the AS group, macroscopic (38.5 vs 5%, P < 0.01) and microscopic (76.8 vs 45%, P = 0.009) lesions were more frequent than in controls; no IBD was diagnosed. Findings were comparable in the axial AS group (n = 25) and the mainly peripheral group (n = 35). In AS patients, marked eosinophilic infiltration was observed in the ascending colon and sigmoid colon but not in the rectum, and this infiltration was more than in controls. The colonic mucosa in controls was otherwise comparable with western studies. Anaemia was seen in 18/60 cases. No association was found between anaemia or HLA-B27 status and gut lesions.

CONCLUSION

There was an equal percentage of microscopic lesions in the whole gut in AS cases and healthy controls. Previous helminth invasions might have played a role. Lesions differ significantly between AS and controls only in the ileum; therefore, the ileal lesions might be more disease related than the colonic ones.

The transition of acute to chronic bowel inflammation in spondyloarthritis

That gut and joint inflammation are linked in spondyloarthritis (SpA) has been recognized for almost three decades. Intriguingly, microscopic gut inflammation, which occurs frequently in patients with SpA, is an important risk factor for clinically overt Crohn's disease and ankylosing spondylitis. This Review describes current insights into the underlying mechanisms that lead to chronic gut inflammation in patients with SpA. We propose that the development of chronic bowel inflammation in these individuals occurs through a transition phase, in which inflammation evolves from an acute into a chronic state. Our transition model implies that different cell types are involved at different stages during disease progression, with stromal cells having an important role in chronicity. In addition, deficient regulatory feedback mechanisms or genetically determined alterations in antigen presentation, endoplasmic reticulum stress, autophagy or cytokine signaling might also favor a transition from self-limiting acute inflammation to chronic inflammation. We anticipate that this transition phase might be an important window for therapeutic intervention.

The colon in patients with ankylosing spondylitis and in normal controls in Bangladesh: a macroscopic and microscopic study

The objective of this paper is to study the macroscopic and microscopic aspects of colonic mucosa in patients with ankylosing spondylitis (AS) and in controls without colonic symptoms in Bangladesh. This observational study was done in a tertiary care center of Dhaka. Twenty-eight consecutive cases of AS were included, fulfilling modified New York Criteria with pure axial form or combined axial and peripheral joint involvement. Ten controls were enrolled in the study from people in whom endoscopy of upper gastrointestinal tract (GI) tract was performed and who had no musculoskeletal complaints and no colonic symptoms. Short colonoscopy (up to 60 cm) and colonoscopic biopsy were done in all. Histological features were evaluated following Cuvelier grading and Rubio and Kock scoring system. Demographic data including age and sex were similar in the AS and control groups. Out of 28 patients, ten had axial and 18 combined axial and peripheral joint disease, mostly pauciarticular. In the AS group, macroscopic and microscopic lesions were found in four and 14 subjects, respectively. Out of 22 subjects without diarrhea, seven had stage II and two had stage I changes. Six subjects in the AS group gave a history of diarrhea, of them three had stage I and two had stage II changes. In the control group, no macroscopic abnormalities were found. On histological examination, the mean diameter of transversely cut rectal glands, interglandular linear distances, number of glands per area, and total digital scores varied between 45-90 microm, 4.6-27 microm, 5-25, and 17-18 respectively. In eight of the ten controls, eosinophilic infiltration was found. Subclinical inflammatory lesions in the colonic mucosa are common in patients with ankylosing spondylitis. Colonic mucosa in normal individuals does not differ from that found in western studies, except for the presence of frequent mild eosinophilic infiltration in the lamina propria.

[Megacolon and arthritis]

In the present report the authors describe four cases with megacolon and arthritis. The etiology of these unique associations is known in only one case. The musculoskeletal pictures belong to the group of seronegative spondyloarthritis. A huge resistance with great scibalas was detected in the left iliac region by physical examination in all cases. Surgical procedures of the colon resulted in complete remission of arthritis in one case, in the others, chronic obstipation with intermittent relapse of arthritis persisted.

CARD15 gene polymorphisms in patients with spondyloarthropathies identify a specific phenotype previously related to Crohn's disease

BACKGROUND

The association between spondyloarthropathy and Crohn's disease is well known. A risk for evolution to Crohn's disease has already been shown in the subgroup of patients with spondyloarthropathy associated with chronic gut inflammation.

OBJECTIVE

To investigate whether the reported polymorphisms in the CARD15 gene, a susceptibility gene for Crohn's disease, are associated with the presence of preclinical intestinal inflammation observed in spondyloarthropathies.

METHODS

104 patients with spondyloarthropathies were studied. All underwent ileocolonoscopy with biopsies between 1983 and 2004. The prevalence of three single nucleotide polymorphisms in the CARD15 gene (R702W, G908R, and 1007fs) was assessed using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR); the patients were compared with an ethnically matched Crohn's disease population and a control population.

RESULTS

The carrier frequency of R702W, G908R, or 1007fs variants in the spondyloarthropathy populations (20%) was similar to the control population (17%), but increased to 38% in the spondyloarthropathy subgroup with chronic gut inflammation. This frequency was significantly higher than in the other spondyloarthropathy subgroups (p = 0.001) or the control group (p = 0.006), but not different from the Crohn's disease group (49%) (NS). This indicates that CARD15 polymorphisms are associated with a higher risk for development of chronic gut inflammation.

CONCLUSIONS

CARD15 gene polymorphisms clearly identify a subgroup of patients with spondyloarthropathies associated with chronic intestinal inflammation.

Infliximab in patients who have spondyloarthropathy: clinical efficacy, safety, and biological immunomodulation

A major breakthrough has been achieved in the treatment of patients who have AS and other types of SpA. The identification of the expression and role of TNF-alpha in patients who have these diseases and the recognition of their relation with gut inflammation (where infliximab therapy has proven efficacious already) has led to the successful use of TNF-alpha blockade in SpA, establishing a new indication for this type of anticytokine therapy. Evidence supports equal response in cases of axial or peripheral disease. Infliximab therapy has been most extensively documented in this new indication for anti-TNF-alpha therapy, but other compounds are also in the field. Gorman et al reported on 40 patients who had active AS who were randomly assigned to receive twice-weekly subcutaneous injections of etanercept (25 mg) or placebo for 4 months [65]. The primary endpoint was a composite of improvements. Treatment with etanercept resulted in significant and sustained improvement (treatment response in 80% in the etanercept group versus 30% in the placebo). Data regarding the human anti-TNF-alpha monoclonal antibody adalimumab in SpA are not yet available. Different questions remain open, including optimal dosing, long-term safety, and effects of this new treatment on the structural articular level; however, a therapeutic breakthrough like the one currently reviewed has seldom occurred in arthritis care.

Gut inflammation and spondyloarthropathies

Spondyloarthropathies (SpA) are a group of related disorders with common clinical and genetic characteristics. The prototype disease in this group is ankylosing spondylitis; other entities include reactive arthritis, psoriatic arthritis, and arthritis in patients with inflammatory bowel disease. Over recent years, there has been a special interest in the relation between spondylitis/synovitis and gut inflammation in patients with SpA. Two thirds of patients with undifferentiated SpA show histologic signs of gut inflammation, and a fraction of these patients go on to develop clinically overt Crohn's disease. In this review, the authors will focus on 1) the growing evidence that has been provided that gut inflammation in SpA is immunologically related to Crohn's disease, based on the molecular characterization of the inflammation (lymphocyte homing markers and ligands, T cell cytokines, macrophage markers, and serology); and 2) on the therapeutic implications resulting from this concept. The recent introduction and positioning of anti-tumor necrosis factor-alpha therapy in patients with ankylosing spondylitis and other types of SpA is, in large part, based on this concept.

Ankylosing spondylitis and bowel disease

Clinical studies indicate an important role for bowel inflammation in ankylosing spondylitis and other spondyloarthropathies whereby two different aspects have to be considered. First, the gut inflammation is clinically and histologically closely related to Crohn's disease. Recent data on subclinical immune alterations confirm this relationship and suggest that spondyloarthropathy is a unique human model for studying early Crohn's disease. Second, bowel and peripheral joint inflammation are clinically, histologically and pathogenetically linked. The most important clinical implication of these observations is that targeted therapies for Crohn's disease could also be effective for intestinal as well as extra-intestinal disease manifestations in spondyloarthropathy, as evidenced by the recent studies on TNF-alpha blockade. Unravelling the gut-synovium axis in spondyloarthopathy could also contribute to the identification of new therapeutic targets. Finally, assessment of subclinical gut inflammation by histology, serology and genetics could contribute to the stratification of individual patients in subgroups with an optimal response to specific therapeutic interventions.

Radiologic diagnosis and pathology of the spondyloarthropathies

Five different subtypes of spondyloarthropathy (SpA) are now recognized. Clinical and radiologic involvement of the sacroiliac joint is an outstanding feature of the SpA, especially ankylosing spondylitis (AS). In this partly debilitating form of SpA a unique type of inflammatory axial involvement is observed which is characterized by inflammation and new bone formation at different spinal sites. In longstanding disease sacroiliitis, spondylitis and spondylodiscitis are easily recognized by conventional radiography and even better by computed tomography--especially when bony changes have already taken place. The advantage of dynamic magnetic resonance imaging (MRI) is to visualize morphologic changes and inflammation at the same time. This facilitates detection of sacroiliitis and spondylitis/spondylodiscitis at early time points. Hopefully, this will lead to other forms of therapy to prevent ankylosis of the spine. The origin of the granulation tissue infiltrating cartilage and bone in AS might be the synovium, the subchondrium or the bone marrow itself. T cells and macrophages seem to play an important role in this inflammatory process in which TNF-alpha is present in severe cases. The mechanisms responsible for the increased bone formation observed in the course of AS are unknown.

The spectrum of skin, mucosa and other extra-articular manifestations

The seronegative spondyloarthropathies appear to be the genetically predisposed host's clinical expression to acute, subacute or chronic reaction to the invasion by environmental microorganisms. In the ensuing days or weeks, depending on the infectious load, clinical manifestations may occur ranging from constitutional complaints such as fever, to a variety of symptoms and/or signs related to the portal of entry-intestinal, genitourinary or respiratory. Within weeks or months, the initial or other target organs, such as the mucocutaneous, ocular and cardiovascular systems, may develop an acute reaction of greater or lesser specificity regarding the triggering agent (oral ulcers, circinate balanitis, erythema nodosum, acute anterior uveitis, pericarditis, heart blocks). Lastly, many years later, a minority of patients, probably those with a large genetic component, exhibit a spectrum of clinical manifestations related to those organs, with a chronic or recurrent course. Acute clinical manifestations--reactive arthritis--are prominent in the initial phase of the clinical spectrum, while chronic manifestations--ankylosing spondylitis--are seen at the other end of the spectrum.

Bowel inflammation and the spondyloarthropathies

The concept of spondyloarthropathies gathers together a group of chronic diseases in which not only the locomotor system is involved but also other organs, especially the gastrointestinal tract. In humans, ileocolonoscopic studies demonstrated the presence of inflammatory gut lesions in all the diseases in the spondyloarthropathy group; their presence varied in the different diseases between 20% and 70%. The inflammation could be related to specific disease features in the spondyloarthropathies. Further research supports the hypothesis of subclinical inflammatory bowel disease in some patients with spondyloarthropathy, in which the locomotor inflammation was the only clinical manifestation. The link between gut inflammation and arthropathy has also been demonstrated in animal models, notably the human leukocyte antigen B27 transgenic rats. The temporal relationship between activity and severity of colonic involvement and flares of peripheral arthritis directs treatment of choice. For all forms of enterogenic arthropathies, nonsteroidal anti-inflammatory drugs remain the acute treatment form. Caution is in order, however, because of their possible harmful effects on intestinal integrity, permeability, and even on gut inflammation.

Review article: bone and joint diseases in inflammatory bowel disease

The intestinal and articular systems are closely linked in inflammatory bowel disease. Clinical and immunological studies support an important aetio-pathogenetic link between intestinal and articular inflammation. There is increasing evidence for a negative link between bone mass density and intestinal inflammation. This paper will focus on the prevalence, aetio-pathogenesis and treatment of arthritis (peripheral, sacroiliitis and spondylitis) and osteoporosis in inflammatory bowel disease.

Course of gut inflammation in spondylarthropathies and therapeutic consequences

Gut inflammation plays a crucial role in the pathogenesis of spondylarthropathies (SpA) since ileocolonoscopic studies have demonstrated the presence of gut inflammation in different forms of this concept: in ankylosing spondylitis (AS) (60%), in enterogenic (90%) and urogenital reactive arthritis (20%), in undifferentiated SpA (65%), in the pauciarticular and axial forms of psoriatic arthritis (16%), in late onset pauciarticular juvenile chronic arthritis (80%) and in acute anterior uveitis (66%). The strong relationship between gut and joint inflammation was demonstrated by performing a second ileocolonoscopy: remission of the joint inflammation was always connected with a disappearance of gut inflammation, whereas persistence of locomotor inflammation was mostly associated with the persistence of gut inflammation. During further evolution 20% of the non-ankylosing spondylitis SpA patients can develop AS. About 6% of the total group SpA patients, in whom inflammatory bowel disease (IBD) was excluded, developed Crohn's disease 5 to 9 years later. All these patients initially presented with gut inflammation, which indicates that this finding has prognostic value. The high prevalence of evolution to IBD in SpA patients confirms the thesis that both disease entities bear common pathogenic mechanisms, and confirms the place of IBD in the concept of SPA. Sulphasalazine (SASP), a successful drug in the treatment of IBD, has demonstrated its effectiveness in the treatment of SpA. The beneficial effect of the drug in this disease entity could be due to its anti-inflammatory effect on the gut wall, by normalizing its permeability and by preventing the entrance of antigens through the defective gut wall. However, SASP could not prevent the evolution to IBD.