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J Belaiche

Publications and source records attributed to J Belaiche.

At least 37 records · Page 2Linked to original sources
PubMed2002

A positive response to infliximab in Crohn disease: association with a higher systemic inflammation before treatment but not with -308 TNF gene polymorphism.

BACKGROUND: Two-thirds to three-fourths of patients with either refractory luminal or fistulizing Crohn disease respond to infliximab treatment. The ability or inability to respond seems to persist over time. Biological characteristics and/or genetic background can influence the response to treatment. The aim was to assess the value of C-reactive protein and TNF-alpha serum levels before treatment as well as the TNF -308 gene polymorphism in the prediction of response to infliximab treatment in Crohn disease. METHODS: Two-hundred-and-twenty-six Crohn disease patients treated in the setting of an expanded access programme to infliximab in Belgium were studied. There were 136 refractory luminal diseases and 90 refractory fistulizing diseases. Luminal diseases were treated with one single infusion; fistulizing diseases with three infusions at weeks 0, 2 and 6. A clinical response to treatment was defined as either a Crohn disease activity index <150 (complete) or a drop of 70 points (partial) at week 4, for luminal disease, and as either complete fistula healing (complete) or a decrease of at least 50% of the number of draining fistulas on two consecutive visits between weeks 0 and 18, for fistulizing disease. CRP and serum TNF-alpha levels were measured at week 0 before treatment and were compared between responders and non-responders. Patients were genotyped for the -308 TNF gene polymorphism, and allelic as well as genotype frequencies were compared between responders and non-responders. RESULTS: There were 73.2% responders (46.4% complete and 26.8% partial) and 26.8% non-responders. Response rates were similar in luminal and fistulizing diseases. CRP level before treatment was significantly higher in responders than in non-responders (16.8 mg/l (5-160) versus 9.6 mg/l (5-143); P = 0.02). Furthermore, response rate was significantly higher in patients with elevated CRP (>5 mg/l) than in patients with a normal CRP value (<5 mg/l) before treatment (76% versus 46%; P=0.004; OR: 0.26 (0.11-0.63)). Allelic and genotype frequencies for -308 TNF gene polymorphism were not significantly different between responders and non-responders--with the exception of a slightly higher TNF2 frequency in non-responders in luminal disease (22.1 % versus 11.6%; P = 0.04). However, this was not associated with a significant difference in genotype frequencies. CONCLUSION: A positive clinical response to infliximab was associated with a higher CRP level before treatment in our population of Crohn disease patients, but there was no relevant association with -308 TNF gene polymorphism. We therefore suggest that CRP level may help to identify better candidates for infliximab treatment.

Adolescent↗
PubMed2001

Association of NOD2 leucine-rich repeat variants with susceptibility to Crohn's disease.

Crohn's disease and ulcerative colitis, the two main types of chronic inflammatory bowel disease, are multifactorial conditions of unknown aetiology. A susceptibility locus for Crohn's disease has been mapped to chromosome 16. Here we have used a positional-cloning strategy, based on linkage analysis followed by linkage disequilibrium mapping, to identify three independent associations for Crohn's disease: a frameshift variant and two missense variants of NOD2, encoding a member of the Apaf-1/Ced-4 superfamily of apoptosis regulators that is expressed in monocytes. These NOD2 variants alter the structure of either the leucine-rich repeat domain of the protein or the adjacent region. NOD2 activates nuclear factor NF-kB; this activating function is regulated by the carboxy-terminal leucine-rich repeat domain, which has an inhibitory role and also acts as an intracellular receptor for components of microbial pathogens. These observations suggest that the NOD2 gene product confers susceptibility to Crohn's disease by altering the recognition of these components and/or by over-activating NF-kB in monocytes, thus documenting a molecular model for the pathogenic mechanism of Crohn's disease that can now be further investigated.

Alleles↗
PubMed2001

Genetic refinement and physical mapping of a chromosome 16q candidate region for inflammatory bowel disease.

Crohn's disease (CD) is a complex genetic disorder for which a susceptibility gene, IBD1, has been mapped within the pericentromeric region of chromosome 16. In order to refine the location of IBD1, 77 multiplex CD families were genotyped for 26 microsatellite markers evenly spaced by approximately 1 cM. Nonparametric linkage analyses exhibited a maximum NPL score of 3.49 (P=2.37x10(-4)) in a region centred by markers D16S3136, D16S3117 and D16S770. Simulation studies showed that the probability for IBD1 to be located in a 5 cM region around these markers was 70%. A 2.5 Mb YAC and BAC contig map spanning this genetic region on chromosome band 16q12 was built. TDT analyses demonstrated suggestive association between the 207 bp allele of D16S3136 (P<0.05) and a new biallellic marker hb27g11f-end (P=0.01). These markers were located in the hb27g11 and hb87b10 BAC clones from the contig. Taken together, the present results provide a crucial preliminary step before an exhaustive linkage disequilibrium mapping of putatively transcribed regions to identify IBD1.

Alleles↗
PubMed2001

Therapeutic drug monitoring of azathioprine and 6-mercaptopurine metabolites in Crohn disease.

BACKGROUND: 6-Mercaptopurine (6-MP) and its prodrug azathioprine (AZA) have proven efficacy in the treatment of Crohn disease (CD). The immunosuppressive properties of AZA/6-MP are mediated by the intracellular metabolism of 6-MP into its active metabolites, 6-thioguanine nucleotides (6TGN) and 6methylmercaptopurine (6-MMP). Preliminary studies have suggested that the red blood cell concentration of 6TGN (RBC 6TGN) is a potential guide to therapy. The aims of the study were to evaluate the RBC 6TGN concentrations in adult patients with CD under long-term AZA/6-MP therapy and to correlate it with response to treatment and haematological parameters. METHODS: Twenty-eight CD patients treated for at least 3 months with AZA/6-MP were prospectively studied. Patients were separated into three main groups: group 1 (n = 19), corresponding to quiescent CD receiving AZA (dose: 2.05 +/- 0.4 mg/kg/day for a mean of 28.6 +/- 25 months) or 6-MP (dose: 1.4 +/- 01 mg/kg/day for a mean of 7.5 +/- 3.5 months) alone; group 2 (n = 6), corresponding to quiescent CD treated by AZA (dose: 2.14 +/- 0.5 mg/kg/day for a mean of 29.5 +/- 22 months) with oral steroids; and group 3 (n = 3), corresponding to active CD on AZA (dose: 1.94 +/- 0.6 mg/kg/day for a mean of 31.3 +/- 35 months) as the only treatment. An assessment was also made by merging groups 1 and 2 forming a larger group of patients (n = 25) defined by clinical remission and groups 2 and 3 forming a larger group of patients (n = 9), non-complete responders with AZA/6-MP alone. Crohn disease index activity (CDAI), blood samples for full blood count and differential white cell count and measurement of RBC 6TGN and 6-MMP concentrations were evaluated at inclusion and at 6 months (n = 17). RBC 6TGN were measured using high performance liquid chromatography (HPLC) on heparinized blood. RESULTS: The baseline characteristics of the three groups of patients were similar. There was no significant difference among the three groups of patients regarding the dose and the duration of immunosuppressive treatment. There was no significant difference between groups according to various parameters tested. Particularly, the median RBC 6TGN concentration at inclusion was similar in the three groups of patients (166 (105-688), 183 (90-261) and 160 (52-194) pmol/8 x 10(8) RBC, respectively). The majority of patients had no detectable level of 6-MMP metabolite, except for 3 patients. There was also no difference between merging groups. Furthermore, there was no significant correlation between RBC 6TGN concentrations and the various biological parameters tested except for the mean erythrocyte volume. At 6 months, all patients of group 1 remained in remission and median RBC 6TGN concentration remained stable. No side effects were observed. CONCLUSIONS: There is, contrary to preliminary studies, a broad overlap in RBC 6TGN levels as well as for haematological parameters in patients in remission or not and responders or not to AZA/6-MP therapy. This suggests, beside a variability in the metabolism of these drugs, the existence of complex mechanisms of action. Nevertheless, beside the use of RBC 6TGN determination to confirm compliance to therapy, this dosage could be useful in non-responding patients, allowing, in absence of leukopenia, to increase the dose of AZA/6-MP safely.

Adult↗
PubMed2001

Increased response of blood eosinophils to various chemotactic agents in quiescent Crohn disease.

BACKGROUND: The number of eosinophils is increased in the mucosae of the digestive and the respiratory tracts in Crohn disease, even clinically quiescent. The mechanisms underlying this panmucosal eosinophilia are unknown. METHODS: The response of blood eosinophils to various chemotactic agents was assessed in 15 patients with clinically quiescent Crohn disease. The results were compared with 15 healthy controls. After purification, eosinophils were placed in Boyden microchambers and the chemotactic effect of PAF (10(-7) M), RANTES (50 ng/ml), IL-5 (0-20 ng/ml), IL-8 (0-50 ng/ml), Eotaxin (0-50 ng/ml) was evaluated. The number of eosinophils in induced sputum of these Crohn disease patients and controls was also assessed and the correlation between chemotaxis and eosinophil count in induced sputum was studied. RESULTS: PAF and RANTES induced a chemotactic effect both in Crohn disease patients and controls. The chemotactic index was significantly higher in Crohn than controls for PAF (2.09+/-0.24 versus 1.37+/-0.14; P < 0.05) but not RANTES. With IL-5, IL-8 and Eotaxin, there was no detectable chemotactic effect in controls while in Crohn, we observed a significant dose-dependent chemotactic effect. Furthermore, with Eotaxin 50 ng/ml, the chemotactic index was significantly higher in Crohn disease patients than controls (2.42+/-0.18 versus 1.56+/-0.28; P < 0.05). A significant increase in sputum eosinophil count and a significant decrease in sputum macrophage count in Crohn disease were observed. However, there was no correlation between eosinophil chemotaxis and sputum eosinophil count in individual patients. CONCLUSION: There is an increased response of blood eosinophils to various chemotactic agents, mainly PAF and Eotaxin, in clinically quiescent Crohn disease. This may participate in the mucosal infiltration by eosinophils in this disease.

Adult↗
PubMed2001

Behaviour of Crohn's disease according to the Vienna classification: changing pattern over the course of the disease.

BACKGROUND: Crohn's disease is a heterogeneous disorder with both a genetic and environmental aetiology. Clinical classifications of the disease, such as the newly proposed Vienna classification, may help to define subgroups of patients suitable for studying the influence of specific genetic or environmental factors. AIM: To assess the stability over the course of the disease of its location and behaviour, as determined according to the Vienna classification. PATIENTS AND METHODS: The notes of 297 Crohn's disease patients regularly followed up at our institution were carefully reviewed retrospectively. The behaviour and location of the disease according to the Vienna classification were determined at diagnosis and after 1, 3, 5, 10, 15, 20, and 25 years of follow up. The proportions of the different behaviours and locations of the disease were calculated at these time points. A statistical analysis of the evolution of these characteristics over 10 years was performed on a subgroup of 125 patients with at least 10 years of follow up. The influence of age at diagnosis on location and behaviour of the disease was assessed as well as the influence of location on the behaviour of the disease. RESULTS: The location of the disease remained relatively stable over the course of the disease. Although the proportion of patients who had a change in disease location became statistically significant after five years (p=0.01), over 10 years only 15.9% of patients had a change in location (p<0.001). We observed a more rapid and prominent change in disease behaviour, which was already statistically significant after one year (p=0.04). Over 10 years, 45.9% of patients had a change in disease behaviour (p<0.0001). The most prominent change was from non-stricturing non-penetrating disease to either stricturing (27.1%; p<0.0001) or penetrating (29.4%; p<0.0001) disease. Age at diagnosis had no influence on either location or behaviour of disease. Ileal Crohn's disease was more often stricturing, and colonic or ileocolonic Crohn's disease was more often penetrating: this was already the case at diagnosis and became more prominent after 10 years (p<0.05). CONCLUSIONS: Location of Crohn's disease, as defined by the Vienna classification, is a relatively stable phenotype which seems suitable for phenotype-genotype analyses. Behaviour of Crohn's disease according to the Vienna classification varies dramatically over the course of the disease and cannot be used in phenotype-genotype analyses. The potential influence of genes on the behaviour of Crohn's disease should be studied in subgroups of patients defined by their disease behaviour after a fixed duration of disease.

Adult↗
PubMed2001

[How I treat ... ascites].

Ascites is the most common of the major complications of cirrhosis. The initial evaluation of a patient with ascites should include a history, physical evaluation and some investigations. Treatment should consist of treating the underlying liver disease, sodium restricted diet (2 g of Na+/day) and diuretics. This regimen is effective in 90% of patients. The treatment options for the diuretic resistant patients include serial therapeutic paracentesis, peritoneovenous shunting, TIPS and liver transplantation. The treatment and prophylaxis of spontaneous bacterial peritonitis which is a frequent and severe complication in cirrhotic patients with ascites is also important. The differential diagnosis with secondary bacterial peritonitis is essential because the latter usually does not resolve unless patients are surgically treated.

Ascites↗
PubMed2000

Frequently relapsing Crohn's disease is characterized by persistent elevation in interleukin-6 and soluble interleukin-2 receptor serum levels during remission.

We examined immune and inflammatory activation during remission in patients with Crohn's disease who presented with various clinical profiles (prolonged remission vs. relapsing disease). Thirty-six patients with at least 3 years' follow-up starting from a remission period were studied retrospectively. Relapses were defined by a retrospective calculation of the Crohn's disease activity index or by the clinical judgement of the physicians in charge of the patients. Disease course over the study period was assessed by the mean number of annual relapses. Analysis used measurements during remission of the following: erythrocytes sedimentation rate, relative lymphocytosis, acid alpha1-glycoprotein, interleukin-6 (IL-6), and soluble interleukin-2 receptor (sIL-2R) serum levels. During the study period 21 patients experienced at least one relapse and 15 did not. Mean serum levels of sIL-2R and mean relative lymphocytosis in remission significantly discriminated between relapsing and nonrelapsing patients. Only the mean sIL-2R serum level was selected by multivariate analysis, with a cutoff value of 82 pM/1 (sensitivity of 76% and specificity of 80%). The only features correlated with mean number of annual relapses in the relapsing patients were mean serum levels of sIL-2R (r=0.58, P=0.015) and IL-6 in remission (r=0.45, P=0.039). Multivariate analysis demonstrated statistical significance only for the mean serum level of IL-6 (P=0.014). In Crohn's disease the persistent elevation in sIL-2R serum levels during remission corresponds to chronic active disease, while high serum levels of IL-6 in these patients is associated with a high frequency of relapse.

Adult↗
PubMed2000

Tumour necrosis factor (TNF) gene polymorphism in Crohn's disease (CD): influence on disease behaviour?

Crohn's disease (CD) is a multifactorial disease with genetic heterogeneity. TNF-alpha plays a key role in the development of the mucosal lesions. The aim of our work was to study a single base pair polymorphism located in the promoter region of TNF gene, in a large population of CD patients with well defined phenotypes. One hundred and ninety-three patients with CD and 98 ethnically matched controls were studied. The -308 single base pair polymorphism of TNF gene was studied using an allele-specific polymerase chain reaction. Genotype and allelic frequencies were compared between patients and controls and between subgroups of patients defined by sex, age at diagnosis, familial history, location of disease, type of disease, extra-intestinal manifestations, and response to steroid treatment. In 29 patients a measure of TNF-alpha production by colonic biopsies was performed. The frequency of the allele TNF2 as well as the proportion of carriers of the allele TNF2 were slightly but not significantly lower in CD than in controls (11.9% versus 14.8% and 21.5% versus 27.6%, respectively). A more prominent difference in frequencies of allele TNF2 and in proportions of TNF2 carriers was found when comparing subgroups of patients. The frequency of allele TNF2 was significantly higher in steroid-dependent than in non-steroid-dependent disease (28.1% versus 10.3%; Delta = 17.8%, 95% confidence interval (CI) = 6.3-29.5%, P = 0.0027) and tended to be higher in colonic than in small bowel disease and in fistulizing than in stricturing disease. Furthermore, TNF2 carriers tended to be more frequent in patients with steroid-dependent than non-steroid-dependent disease (43.8% versus 19.3%; Delta = 24.5%, 95% CI = 3.6-45.4%, P = 0.022), in patients with fistulizing than stricturing disease (26.5% versus 9.6%; Delta = 16.9%, 95% CI = 1. 1-32.6%, P = 0.036), and in patients with colonic than small bowel disease (26.5% versus 11.1%; Delta = 15.4%, 95% CI = -0.8-31.6%, P = 0.063). Finally, patients carrying at least one copy of allele 2 were found to produce slightly more TNF-alpha at the colonic level. The -308 TNF gene polymorphism may have a slight influence on the behaviour of CD. The carriage of allele 2 may favour steroid-dependent disease and to a lesser extent fistulizing and colonic disease, possibly secondary to a more intense TNF-alpha-driven inflammatory reaction at the mucosal level.

Adult↗
PubMed2000

Increased production of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 by inflamed mucosa in inflammatory bowel disease.

Inflammatory bowel diseases (IBD) are characterized by a sustained inflammatory cascade that gives rise to the release of mediators capable of degrading and modifying bowel wall structure. Our aims were (i) to measure the production of matrix metalloproteinase-3 (MMP-3), and its tissue inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), by inflamed and uninflamed colonic mucosa in IBD, and (ii) to correlate their production with that of proinflammatory cytokines and the anti-inflammatory cytokine, IL-10. Thirty-eight patients with IBD, including 25 with Crohn's disease and 13 with ulcerative colitis, were included. Ten controls were also studied. Biopsies were taken from inflamed and uninflamed regions and inflammation was graded both macroscopically and histologically. Organ cultures were performed for 18 h. Tumour necrosis factor-alpha (TNF-alpha), IL-6, IL-1beta, IL-10, MMP-3 and TIMP-1 concentrations were measured using specific immunoassays. The production of both MMP-3 and the TIMP-1 were either undetectable or below the sensitivity of our immunoassay in the vast majority of uninflamed samples either from controls or from those with Crohn's disease or ulcerative colitis. In inflamed mucosa, the production of these mediators increased significantly both in Crohn's disease (P < 0.01 and 0.001, respectively) and ulcerative colitis (P < 0.001 and 0.001, respectively). Mediator production in both cases was significantly correlated with the production of proinflammatory cytokines and IL-10, as well as with the degree of macroscopic and microscopic inflammation. Inflamed mucosa of both Crohn's disease and ulcerative colitis show increased production of both MMP-3 and its tissue inhibitor, which correlates very well with production of IL-1beta, IL-6, TNF-alpha and IL-10.

Adult↗
PubMed2000

Acute pancreatitis attributed to the use of interferon alfa-2b.

Two patients experienced episodes of acute pancreatitis shortly after starting treatment with interferon alfa-2b (IFN-alpha) for a chronic hepatitis C infection. The first patient was a 40-year-old man who developed acute pancreatitis after 15 weeks of treatment with 3 MU IFN-alpha subcutaneously (SC) 3 times weekly and 1200 mg ribavirin. After disappearance of symptoms and normalization of laboratory values, oral intake of solid foods and IFN-alpha therapy were restarted. Within hours, a relapse of acute pancreatitis occurred. A rechallenge with IFN-alpha 4 days later was followed by a prompt increase in serum lipase level, and IFN-alpha therapy was discontinued. The second patient was a 38-year-old man who developed acute pancreatitis 2 hours after SC administration of 5 MU IFN-alpha. Ultrasound endoscopy showed sludge in the gallbladder. The patient was rechallenged 5 weeks later with 3 MU IFN-alpha SC. Although serum amylase and lipase levels increased after readministration of IFN-alpha, treatment was continued. The patient was readmitted 2 weeks later with severe abdominal pain, and IFN-alpha administration was discontinued. Considering the temporal relationship between the start of IFN-alpha treatment and development of acute pancreatitis, the absence of other clear etiologic factors for acute pancreatitis, disappearance of symptoms after discontinuation of IFN-alpha, and positive reactions to rechallenge, IFN-alpha is the most probable cause for development of acute pancreatitis in these patients.

Abdominal Pain↗
PubMed2000

Genetic analyses of chromosome 12 loci in Crohn's disease.

BACKGROUND AND AIMS: Inflammatory bowel disease (IBD) includes ulcerative colitis and Crohn's disease, both of which are multifactorial diseases involving the interaction of genetic and environmental factors. A region on chromosome 12 centred around the marker locus D12S83 has previously been associated with IBD predisposition. The aim of the study was to investigate this genetic region in an independent panel of European families affected by Crohn's disease. METHODS: A sample of 95 families with two or more affected relatives and 75 simplex nuclear families were genotyped for 19 microsatellite loci located on chromosome 12. A search for linkage and linkage disequilibrium was performed using non-parametric two point and multipoint analyses with the Analyze and Genehunter packages. RESULTS: No evidence of linkage or linkage disequilibrium was observed for any of the marker loci, including D12S83 (p=0.35 for the two point linkage test). Multipoint linkage analysis also failed to reveal positive linkage on chromosome 12. Power calculations allowed us to reject the hypothesis that the genetic region of chromosome 12 centred on D12S83 contains a susceptibility locus with a relative risk (lambda(s)) equal to or greater than 2.0 in these families. CONCLUSION: Failure to detect linkage or linkage disequilibrium in these families suggests that the chromosome 12 locus previously reported to be associated with genetic predisposition to IBD does not play a role in all European family samples. This observation is compatible with heterogeneity in the genetic basis of susceptibility to the disease and/or exposure to various environmental factors among Caucasian families.

Chromosomes, Human, Pair 12↗
PubMed2000

[Gastroesophageal reflux in the adult: diagnosis and treatment].

Gastro-oesophageal reflux is a frequent problem affecting up to one third of the Belgian adult population. It is most often a benign non evolutive disease. It is however frequently chronic, with a significant negative impact on quality of life. The diagnostic and therapeutic management must be adapted to each individual case. In the majority of cases, the purpose of therapy is the control of symptoms and, in a small number of cases with severe oesophagitis the aim is a complete and persistent healing of lesions. A Franco-Belgian consensus meeting on diagnostic and therapeutic management of gastro-oesophageal reflux disease in adults was recently held. Guidelines have been proposed. The aim of the present paper is to highlight the main principles of these guidelines and to comment on their adjustment to current belgian medical practice.

Adult↗
PubMed2000

[Treatment of Crohn disease in adults with tumor necrosis factor-alpha (TNF-alpha) antibodies].

Crohn's disease (CD) is a chronic inflammatory disease of the bowel characterized by segmental transmural inflammation and granulomatous changes. TNF alpha is a member of a large family of proteins and receptors that are involved in immune regulation. It is a proinflammatory and immunoregulatory cytokine synthesized by monocytes, macrophages, and T cells. TNF alpha plays an early central role in the cytokine cascade of the inflammatory process. Recently, chimeric monoclonal antibodies that inhibits TNF alpha have been used in the treatment of Crohn's disease. Infliximab has been the most largely used antibody. It is commercialized in the USA and has recently obtained an European marketing approvement. Infliximab is indicated for the treatment of moderately to severely active CD in patients having an inadequate response to conventional therapy. Clinical trials have demonstrated efficacy when the agent is initiated as a 5 mg/kg single intravenous infusion. In patients with fistulizing CD, administration of 2 subsequent 5 mg/kg doses 2 and 6 weeks after the initial dose appears to be efficacious. Limited clinical data also suggest that infliximab retreatment regimen restores response and maintains remission rates. Infliximab appears to be well tolerated. To date, very little is known about the potential for long-term toxicity with infliximab therapy.

Adult↗
PubMed2000

[Gitelman syndrome: a rare cause of hypokalemia].

We report a case of hypokaliemia whose origin is a urinary potassium loss associated with syndrome of Gitelman. The syndrome of Gitelman is a rare familiar autosomal recessive nephropathy. We will discuss the pathophysiology of this syndrome and differential diagnoses.

Adult↗
PubMed1999

Decreased corticosensitivity in quiescent Crohn's disease: an ex vivo study using whole blood cell cultures.

Corticosensitivity influences the degree and the duration of an inflammatory reaction by altering target cell responses to endogenous and/or exogenous glucocorticoids. Indeed, different clinical responses to glucocorticoids have been observed among patients with Crohn's disease, suggesting different degrees of corticosensitivity in these subjects. The purpose of this study was to compare the corticosensitivity of patients with quiescent Crohn's disease to that of healthy subjects (HS). Nineteen patients with quiescent Crohn's disease and 14 HS were studied; all patients were steroid-free for at least six months; 7 of the 19 were corticosteroid-dependent (CSD) and treated with nonglucocorticoid immunosuppressants at the time of the study. Corticosensitivity was measured by the inhibition of LPS-induced cytokine secretion in whole blood cell cultures treated with increasing concentrations (10(-9) to 10(-6) M) of dexamethasone. Tumor-necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-1 beta (IL-1 beta) were measured using specific immunoassays. Crohn's disease patients had a markedly decreased dexamethasone-mediated inhibition of TNF-alpha (P < 0.01), IL-6 (P < 0.001), and IL-1 beta (P < 0.01) compared to healthy subjects, with a shift of the dexamethasone dose-response curve to the right. No significant differences in the basal and LPS-stimulated secretion of the three cytokines were observed between CSD and non-CSD patients, and both subgroups of patients had similar degrees of dexamethasone-mediated cytokine inhibition. We conclude that patients with Crohn's disease have a significant decrease in the corticosensitivity of their leukocytes. This may be related to a specific genetic/constitutional background and/or could be acquired, due to inflammation-related endocrine and/or immune factors.

Adult↗
PubMed1999

Bronchial eosinophilic infiltration in Crohn's disease in the absence of pulmonary disease.

BACKGROUND: Immunological and functional bronchopulmonary abnormalities may be present in up to two-thirds of patients with Crohn's disease. Having recently described a mild increase in methacholine airways responsiveness in these patients, we investigated whether this physiological abnormality is associated with bronchial inflammation since it has previously been described in asthma. METHODS: Eighteen patients with Crohn's disease and 15 healthy controls matched for age, atopy and smoking habit, were studied. All the subjects underwent a bronchial methacholine challenge (1, 4 and 16 mg/mL) and a sputum induction by inhalation of hypertonic saline (NaCl 4.5%). The sputum samples were analysed for their cellular composition as well as for the levels of several mediators and proteins in the fluid phase, including eosinophil cationic protein (ECP), myeloperoxydase, albumin, alpha2-macroglobulin, interleukin-8 (IL-8), IgA and IL-8/immunoglobulin A complexes. RESULTS: When compared to control subjects, patients with Crohn's disease had significantly higher sputum eosinophil counts (14.5% [0-79.9%] vs 0.2% [0-2.3%]; P < 0. 001) and ECP levels (26.2 microg/L [4-124.2 microg/L] vs 9.8 microg/L [0-94.2 microg/L]; P < 0.05). However, patients with Crohn's disease had no sign of increased plasma exudation as reflected by sputum levels of albumin and alpha2-macroglobulin similar to those seen in control subjects. Furthermore the sputum levels of IL-8, IgA and IL-8/IgA complexes were not significantly different between the two groups. The magnitude of the fall in forced expiratory volume in 1 s after methacholine inhalation was significantly increased in Crohn's disease patients although it did not correlate with the extent of sputum eosinophilia or with the sputum ECP levels. CONCLUSIONS: Crohn's disease patients without any clinical respiratory involvement have airway eosinophilia without local increased plasma exudation. However, bronchial eosinophilia in Crohn's disease per se is not sufficient to induce clinically significant airway hyperresponsiveness, suggesting that other factors than bronchial eosinophilic infiltration are required for the clinical expression of an airway instability.

Adult↗