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C Cuvelier

Publications and source records attributed to C Cuvelier.

At least 55 records · Page 3Linked to original sources

The gut associated addressins: lymphocyte homing in the gut.

The process of lymphocyte trafficking is mainly regulated by receptors that belong to a group of molecules referred to as adhesion molecules. These molecules can be divided, according to their molecular structure, into three broad families: the integrins; the selectins; and the immunoglobulin superfamily members. The alpha 4 beta 7 integrin is expressed on some lymphocytes with hallmarks of gut tropism. alpha 4 beta 7, among others, serves as a ligand for the mucosal vascular addressin MadCAM-1, which is selectively expressed on mucosal lymphoid organ high endothelial venules and on gut lamina propria venules. It is tempting to believe that related integrin receptors play a crucial role in the recirculation of activated lymphocytes between the gut mucosa and the synovial membrane.

Animals↗

Spondylarthropathies: from gut to target organs.

Recent studies strongly support the concept that gut and joint inflammation are closely related. Progress also has been made in identifying individual mechanisms that contribute to the pathogenesis of joint disease in IBD and in undifferentiated SpAs. However, the interrelationship of these mechanisms that result in chronic disease manifestations at a site distant from the initiating event remain to be elucidated. The local absence of homing molecule receptors in the gut wall combined with an expression of these receptors in target organs can be responsible for the transformation of the synovial membrane and/or the enthesis into an aberrant tertiary lymphoid organ of the gut.

Animals↗

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.

Arthritis, Rheumatoid↗

Long-term evolution of gut inflammation in patients with spondyloarthropathy.

BACKGROUND & AIMS: Intestinal inflammation has been observed in patients with spondyloarthropathy (SpA). This prospective study reports the evolution of the intestinal inflammation observed in patients with SpA. METHODS: One hundred twenty-three patients with SpA who had undergone initial endoscopy were clinically reassessed. Intestinal evolution was evaluated by ileocolonoscopy and the histological study of biopsy specimens in 49 patients. RESULTS: Articular remission rates were independent of initial gut inflammation and associated with endoscopic and histological remission. Persistent gut inflammation was observed in active joint disease. Gut inflammation rarely disappeared, despite the persistence of articular complaints. Initial chronic gut inflammation implied a high risk of evolution to ankylosing spondylitis. Evolution to inflammatory bowel disease (IBD) was observed in 7% of patients. Mainly patients with initial chronic inflammation and mild complaints of diarrhea were at risk. Sulfasalazine was more frequently needed in the treatment of patients with gut inflammation with a beneficial effect on articular and intestinal evolution but did not prevent evolution to IBD. CONCLUSIONS: This study supports the etiopathogenetic role of the gut in SpA. Presence of chronic gut inflammation and mild complaints of diarrhea implies a high risk of evolution to ankylosing spondylitis and IBD. Sulfasalazine has a beneficial effect on articular activity by controlling gut inflammation, but it cannot prevent evolution to overt IBD.

Adolescent↗

The role of gut inflammation in the pathogenesis of spondyloarthropathies.

The concept of spondyloarthropathy (SpA) gathers together a group of chronic diseases with common clinical, biological, genetic and therapeutic characteristics. The concept forms a distinct entity, different from other rheumatic diseases. The target organs are not only the joint, but also the axial skeleton, the enthesis, the eye, the gut, urogenital tract, the skin and sometimes the heart. The prevalence of this entity in the general population is estimated 1%, equal to the prevalence of rheumatoid arthritis. Genetical predisposition (HLA-B27) is one of the clues to the pathogenesis of the disease. Since reactive arthritis is induced by specific urogenital or enterogenic bacteriae, and since the gut is implicated in different forms of spondyloarthropathies, especially in IBD, it was clear that the gut could play an important role by permitting exogenous factors to enter the body. This hypothesis was the rationale for investigating the gut in the spondyloarthropathies by performing ileocolonoscopies. In the first ileocolonoscopic studies of SpA patients, histological signs of gut inflammation were found in a relatively great number of patients, mostly without any clinical intestinal manifestations. These lesions were not seen in other inflammatory joint diseases. Further ileocolonoscopic studies confirmed the strong relationship between gut and joint inflammation. In patients in whom a second ileocolonoscopy was performed, remission of the joint inflammation was always connected with a disappearance of the gut inflammation, whereas persistence of locomotor inflammation was mostly associated to the persistence of gut inflammation. The hypothesis was proposed that some patients with a spondyloarthropathy had a form of subclinical Crohn's disease in which the locomotor inflammation was the only clinical expression. This hypothesis was confirmed in prospective long-term studies in which the ileocolonoscoped patients were reviewed 2 to 9 years later: about 6% of SpA patients not presenting any sign of Crohn's disease at first investigation but demonstrating gut inflammation on biopsy, developed full-blown Crohn's disease. The discovery of subclinical gut inflammation in the SpA had therapeutic consequences. Sulphasalazine (SASP) has been proven to be an active drug in the treatment of IBD. Since the gut could play a crucial role in SpA, it was logic to use this drug in the treatment of this disease. Multiple open and double-blind studies have proven the effectiveness of this drug in SpA; recent studies concluded that the beneficial effect of the drug in this disease entity is more prominent on the peripheral arthritis than on the axial disease.

Anti-Inflammatory Agents↗

Immunohistochemical analyses of the lymphoepithelium in human nasopharyngeal associated lymphoid tissue (NALT): preliminary results.

M-cells and their lymphoepithelial contacts were studied in a morphological study by using electron microscopy. To get insight into lymphoepithelial interactions and inflammatory processes in the NALT we compared M-cell rich areas (established by electron microscopy) in adenoids and tonsils, with areas lacking M-cells and intraepithelial lymphoid cells. Immunohistochemical techniques were used.

Adolescent↗

Ultrastructural investigation of M-cells and lymphoepithelial contacts in naso-pharyngeal associated lymphoid tissue (NALT).

The nasopharyngeal and palatine tonsil, two lymphoepithelial structures situated at the entrance of respiratory and gastrointestinal tracts, show striking similarity with lymphoid tissue of bronchus and gut (BALT, GALT). The information obtained by previous investigations in our laboratory on M-cells in the lymphoepithelium of the Peyer's patches (PP) served as a guidance in our search for M-cells in adenoids and tonsils.

Adenoids↗

The role of T cells in rheumatoid arthritis.

The most striking arguments in favor of a T cell dependent nature of RA are the strong association of the disease with selected class II HLA haplotypes (the "shared epitope" hypothesis) and the fact that, in experimental animal models such as adjuvant arthritis, the disease can be transferred by isolated T cell lines. It is true that T cell activation at the site of inflammation is not excessive. However, there is now unequivocal evidence for focal synthesis of IL-2 and IFN-gamma in the RA synovial membrane and one may realise that a limited but specific T cell activation may be sufficient to induce or perpetuate the immune process. This same argument may explain the lack of clear TCR restriction at the sites of inflammation. Until now, no antigen has been demonstrated to initiate and/or perpetuate RA. Different antigens though have been incriminated in the pathogenesis of RA, including cartilage antigens (collagen, proteoglycans, chondrocyte antigens), heat shock proteins or exogenous (viral/bacterial) antigens. Unless one can pick up the right antigen and clone the relevant T cells, it will be very hard to directly prove a T cell-dependent nature of the disease.

Animals↗

Gut inflammation in psoriatic arthritis: a prospective ileocolonoscopic study.

OBJECTIVE: Some forms of psoriatic arthritis (PsA) are classified as spondylarthropathy, and subclinical gut inflammation is found in spondylarthropathies. Our study was designed to determine if inflammatory gut lesions were also present in PsA, and if the prevalence of subclinical gut involvement was different in the subgroups of this disease. The relationship with HLA subtypes was also determined. METHODS: Ileocolonoscopy was performed on 64 patients with PsA (37 men, 27 women). RESULTS: Inflammatory gut lesions were found in 10 of the 64 patients (16%): in 3 of the 15 patients (20%) with oligoarthritis and in 7 of the 23 patients (30%) with axial involvement. None of the 26 patients with polyarthritis showed these lesions. The prevalence of HLA-B27, Bw62, and B17 was significantly raised in our total group of patients with PsA. HLA-B27 and Bw62 were significantly more prevalent in patients with gut inflammation, 60 and 50%, respectively. CONCLUSION: Gut inflammation is only present in PsA subgroups that belong to the spondylarthropathy concept. This suggests that the gut plays a role in the pathogenesis of locomotor inflammation in these subgroups. The prevalence of gut inflammation in psoriatic spondylarthropathy is significantly lower than in nonpsoriatic spondylarthropathies. Consequently, not only the gut but also the skin may be a portal of entry for causative antigens in PsA.

Adolescent↗

Thallium-201 accumulation in myositis ossificans and in juxta-articular ossification.

We present the findings on 201Tl and 99mTc-MDP scintigraphy in three patients suffering from heterotopic ossification (two patients presenting with myositis ossificans and one patient presenting with juxta-articular ossification in combination with myositis ossificans). Since resection of the lesions has to be delayed until stabilization, 99mTc-MDP is often used as a parameter of lesional activity, although it is not optimal. For this clinical problem, we evaluated 201Tl scintigraphy as a marker of metabolic activity. In addition to the well-documented uptake of 99mTc-MDP, marked accumulation of 201Tl was observed in all heterotopic ossification sites. Hence, our results support the use of 201Tl scintigraphy in the therapeutic management and monitoring of conditions associated with ectopic ossification. On the other hand, although myositis ossificans is sometimes clinically, radiographically and even histologically confused with extraosseous osteogenic sarcoma, 201Tl accumulation may not be a helpful factor in the differential diagnosis due to the presence of tracer accumulation in both disorders.

Adult↗

The evolution of spondyloarthropathies in relation to gut histology. I. Clinical aspects.

OBJECTIVE: To study prospectively the clinical evolution of different forms of spondyloarthropathy (SpA) (excluding inflammatory bowel disease, IBD): reactive arthritis, undifferentiated SpA, and ankylosing spondylitis (AS). METHODS: Ileocolonoscopy was performed on 217 patients with SpA (149 men, 68 women). They also underwent clinical, laboratory, and radiological examinations. Two to 9 years later, 123 patients (84 men, 39 women) who had been regularly monitored were reviewed and given the same examinations. For the remaining 94 patients clinical data were obtained by telephone. RESULTS: At the time of clinical review, 53 (43%) of the regularly monitored patients were in clinical remission. The remission rate was higher in patients with non-ankylosing spondylitis SpA (non-As-SpA) than in patients with AS (19%). Fourteen patients with non-AS-SpA had developed AS; 4 of them also had IBD. IBD was also found in 4 patients with AS and in 3 patients from the telephone group. The prevalence of HLA-B27 was significantly higher in all SpA subgroups, while HLA-BW62 was elevated in the undifferentiated SpA. At review, HLA-B27 was significantly more prevalent in patients with persistent locomotor inflammation compared to patients in clinical remission, while HLA-BW62 was predominant in the latter group. CONCLUSION: Patients with SpA, especially those with non-AS-SpA, have a good longterm prognosis. However, patients with non-AS-SpA may develop AS. Six percent of the patients with SpA in whom manifestations of IBD are absent will develop this disease. This confirms the hypothesis that some of these patients with SpA initially have a form of subclinical Crohn's disease, of which locomotor inflammation is the only clinical expression. HLA-B27 positivity predisposes to a more severe course of locomotor inflammation, while HLA-BW62 has a protective effect but is associated with gut inflammation.

Adolescent↗

The evolution of spondyloarthropathies in relation to gut histology. II. Histological aspects.

OBJECTIVE: To study prospectively the clinical evolution of different forms of spondyloarthropathy (SpA) in relation to the type of gut histology in ileocolonoscopic biopsy specimens. METHODS: Ileocolonoscopy was performed in 217 patients with SpA (149 men, 68 women). Three types of gut histology (normal gut histology and acute and chronic inflammatory gut lesions) were found. Clinical, laboratory, and radiological examinations were performed at start and 2 to 9 years later in 123 patients who were regularly monitored. For the remaining 94 patients clinical data were obtained by telephone. RESULTS: Of the 123 patients monitored regularly, 40 (32%) had normal gut histology, and 28 (23%) had acute and 55 (45%) chronic inflammatory gut lesions. Acute lesions were preferentially found in patients with non-ankylosing spondylitis SpA (non-AS-SpA). In the groups with normal gut histology and with chronic gut inflammation, patients with ankylosing spondylitis (AS) and non-AS-SpA were present in equal numbers. At review, clinical evolution was identical in the 3 histological subgroups. Eight patients developed idiopathic inflammatory bowel disease (IBD), one with initially acute gut inflammation, 7 with initially chronic gut inflammation. All had active AS at review. Fourteen patients with non-AS-SpA developed AS; 13 of them had initially presented inflammatory gut lesions. Three patients in the telephone group also developed IBD; all had active AS at review and initially presented chronic inflammatory gut lesions. Persistently high inflammatory serum variables, HLA-B27 negativity in the presence of sacroiliitis or AS, and inflammatory gut lesions at the first ileocolonoscopy indicate patients with SpA are at risk for developing IBD. CONCLUSION: Gut inflammation, mainly subclinical, could be demonstrated in 68% of patients with SpA. Acute gut inflammation was predominant in patients with reactive arthritis (ReA). The evolution to clinical remission was not influenced by the presence or the type of gut inflammation at start. Patients with non-AS-SpA with inflammatory gut lesions have greater risk of developing AS. One patient with Yersinia induced ReA developed AS and IBD. In total, 11 patients (66%) developed IBD, all initially presenting inflammatory gut lesions. Ten had chronic gut lesions, suggesting this type of gut inflammation is related to the inflammation of Crohn's disease. This type of gut inflammation, the persistence of high inflammatory serum variables, and the absence of HLA-B27 in patients with AS are risk factors for developing IBD.

Adolescent↗

The evolution of spondyloarthropathies in relation to gut histology. III. Relation between gut and joint.

OBJECTIVE: To study prospectively the clinical evolution of different forms of spondyloarthropathy (SpA) in relation to the evolution of gut histology in consecutive ileocolonoscopic biopsy specimens. METHODS: Ileocolonoscopy was performed in 49 patients with SpA (34 men, 15 women). They also underwent clinical, laboratory, and radiological examinations. Two to 9 years later, a 2nd and sometimes a 3rd or 4th ileocolonoscopy was performed, and the other examinations were repeated. RESULTS: At first ileocolonoscopy, 34 patients (69%) showed inflammatory gut lesions. At the 2nd ileocolonoscopy, 16 patients (32%) were in clinical remission; none were found to have inflammatory gut lesions. Of the 33 patients with persistent locomotor inflammation, 14 had persistent inflammatory gut lesions, predominantly the chronic type. Of these 14 patients, 6 had developed inflammatory bowel disease (IBD). None of the 15 patients with an initially normal gut histology had gut inflammation at 2nd examination. Of the 9 with initially acute lesions, 3 developed chronic lesions (1 Crohn's disease). Initial chronic lesions in 25 patients persisted in 9, of whom 5 had developed IBD. Seven of the 19 patients with non-SpA ankylosing spondylitis (non-AS-SpA) developed ankylosing spondylitis (AS); all had initially presented inflammatory gut lesions, which persisted at 2nd examination. In the 11 patients with more than 2 consecutive ileocolonoscopies, clinical remission was always associated with normal gut histology, and flares of the joint disease were related temporally to the reappearance of gut inflammation. CONCLUSION: This study demonstrates the close relationship between gut and locomotor inflammation in SpA. Clinical remission was always associated with normal gut histology, whereas active locomotor inflammation was usually associated with the presence of gut inflammation. Absence of gut inflammation in the SpA is a good prognostic indicator, since gut inflammation or IBD never develops in these patients. Evolution of non-AS-SpA to full blown AS or of uncomplicated SpA to a form of IBD was always associated with gut inflammation at disease onset.

Adolescent↗

Bronchopneumonia caused by Propionibacterium acnes.

Propionibacterium acnes was identified as the pathogen in a case of subacute lung infection by examination of an open lung biopsy specimen. The patient was a 65-year-old male with exacerbation of chronic lung disease. The organism was isolated in pure culture and was present in large numbers on Gram stain. Histological examination demonstrated active interstitial fibrosis; macrophages laden with Propionibacterium acnes antigen were revealed using a peroxidase-antiperoxidase stain. This is the first report of subacute infection of pulmonary tissue due to this organism.

Aged↗

Diagnostic usefulness of radiolabeled pentetreotide scintigraphy and therapeutic efficiency of octreotide in a case of insulinoma.

Although the functional diagnosis of insulinoma is quite easy, its topographic diagnosis still constitutes a major challenge since conventional radiological techniques, e.g. ultrasonography, computed tomography and even selective angiography, fail to recognize the tumor in numbers of insulinomas. We report an observation of a benign insulinoma in an 81-year-old woman that escaped detection by ultrasonography and CT but was later localized by both endoscopic ultrasonography and somatostatin receptor scintigraphy. It illustrates the usefulness of such recent imaging techniques for the localization of islet cell tumors that escaped detection by ultrasonography and CT. Moreover, in our elderly patient who refused surgical intervention, hypoglycemia was corrected by octreotide administration emphasizing the predictive value of 111In-pentetreotide scintigraphy on the subsequent response to octreotide therapy in patients in whom the optimal treatment (surgical resection) is not possible.

Aged↗