Clustering of Crohn's disease within affected sibships

Crohn's disease (CD) is a complex genetic disorder for which aetiology is unknown. Recently, genetic factors for susceptibility have been described. Several genetic loci have been mapped and partially explain the familial aggregations of the disease. However, environmental factors may also contribute to these aggregations. We considered that if the role of non-genetic factors was negligible, CD patients would be randomly distributed in sibships with multiple affected siblings. On the other hand if there was a significant environmental contribution, the siblings would be affected non-randomly over exposure status. In order to test this hypothesis, we studied 102 sibships with two or more affected siblings. A statistical test, named Cluster of Affected Sibling Test or CAST, was developed, based on the exact calculation of the probability of observing a given number of clusters of affected siblings in multiplex families. The null hypothesis of a random distribution of affected siblings was rejected (P=0.005). The observed excess of affected sibling clusters indicates that birth order influences the disease status. Considering that an adjacent order of birth is a global estimate of environmental sharing, this observation strongly suggests that environmental factors contribute to the observed familial aggregations of the disease. This observation provides evidence that familial CD is a relevant tool for further studies of environmental factors and gene-environment interaction. More generally, the CAST statistics may be widely applicable to estimate the involvement of environmental factors in the aetiology of other binary traits which may be observed in multiple members of the same sibship.

CARD4/NOD1 is not involved in inflammatory bowel disease

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are complex genetic disorders. CARD15/NOD2, a member of the Ced4 superfamily which includes Apaf-1 and CARD4/NOD1, has recently been associated with genetic predisposition to CD but additional genetic factors remain to be identified. Because CARD4/NOD1 shares many structural and functional similarities with CARD15, we tested its putative role in IBD.

PATIENTS AND METHODS

The 11 exons of CARD4 were screened for the presence of variants in 63 unrelated IBD patients. The only non-private genetic variation encoding for a substitution in the peptidic chain was genotyped in 381 IBD families (235 CD, 58 UC, 81 mixed, and seven indeterminate colitis families) using a polymerase chain reaction-restriction fragment length polymorphism procedure. Genotyping data were analysed by the transmission disequilibrium test.

RESULTS

Five of nine sequence variations identified in the coding sequence of the gene encoded for non-conservative changes (E266K, D372N, R705Q, T787M, and T787K). Four were present in only one family. The remaining variant (E266K), which exhibited an allele frequency of 0.28, was not associated with CD, UC, or IBD. Furthermore, IBD patients carrying sequence variations in their CARD4 gene had a similar phenotype to those with a normal sequence.

CONCLUSION

Our results suggest that CARD4 does not play a major role in genetic susceptibility to IBD.

Pregnancy and inflammatory bowel disease

Overall, around 25% of women with inflammatory bowel disease will conceive during their disease. Most of the women with inflammatory bowel disease will have a normal pregnancy and healthy children. However, specific problems may arise related to these pregnancies. This paper reviews what is known on fertility, risk of disease transmission, effect of the disease on the pregnancy and the reverse, delivery, medical follow up and treatment as well as breastfeeding in the setting of inflammatory bowel disease.

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.

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.

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.

Serological markers for prediction of response to anti-tumor necrosis factor treatment in Crohn's disease

OBJECTIVES

The use of monoclonal anti-tumor necrosis factor (TNF) antibodies (infliximab, Remicade) is a new therapeutic approach for severe refractory luminal or fistulizing, Crohn's disease (CD). However, up to 30% of patients do not respond to this treatment. So far, no parameters predictive of response to anti-TNF have been identified. Our aim was to determine whether serological markers ASCA (anti-Saccharomyces cerevisiae antibodies) or pANCA (perinuclear antineutrophil cytoplasmic antibodies) could identify Crohn's patients likely to benefit from anti-TNF therapy.

METHODS

Serum samples of 279 CD patients were analyzed for ASCA and pANCA before anti-TNF therapy. A blinded physician determined clinical response at week 4 (refractory luminal CD) or week 10 (fistulizing CD) after the first infusion of infliximab (5 mg/kg).

RESULTS

Overall, there was no relationship between ASCA or pANCA and response to therapy. However, lower response rates were observed for patients with refractory intestinal disease carrying the pANCA+/ASCA- combination, although this lacked significance (p = 0.067).

CONCLUSIONS

In this cohort of infliximab-treated patients, neither ASCA nor pANCA could predict response to treatment. However, the combination pANCA+/ASCA- might warrant further investigation for its value in predicting nonresponse in patients with refractory luminal disease.

Osteoporosis in inflammatory bowel disease: effect of calcium and vitamin D with or without fluoride

BACKGROUND

Previous data have indicated low bone formation as a mechanism of osteoporosis in inflammatory bowel disease. Fluoride can stimulate bone formation.

AIM

To assess the effect of fluoride supplementation on lumbar spine bone mineral density in osteoporotic patients with inflammatory bowel disease treated in parallel with calcium and vitamin D.

METHODS

In this prospective, randomized, double-blind, parallel and placebo-controlled study, 94 patients with inflammatory bowel disease (lumbar spine T score below - 2 standard deviations, normal serum 25OH vitamin D), with a median age of 35 years, were included. Bone mineral density was measured by dual-energy X-ray absorptiometry. Patients were randomized to receive daily either sodium monofluorophosphate (150 mg, n=45) or placebo (n=49) for 1 year, and all received calcium (1 g) and vitamin D (800 IU). The relative change in bone mineral density from 0 to 12 months was tested in each group (fluoride or placebo) and compared between the groups.

RESULTS

Lumbar spine bone mineral density increased significantly in both groups after 1 year: 4.8 +/- 5.6% (n=29) and 3.2 +/- 3.8% (n=31) in the calcium-vitamin D-fluoride and calcium-vitamin D-placebo groups, respectively (P < 0.001 for each group). There was no difference between the groups (P=0.403). Similar results were observed according to corticosteroid intake or disease activity.

CONCLUSIONS

Calcium and vitamin D seem to increase lumbar spine density in osteoporotic patients with inflammatory bowel disease; fluoride does not provide further benefit.

Observational survey of NSAID-related upper gastro-intestinal adverse events in Belgium

OBJECTIVES

To evaluate the impact of NSAID use on current routine upper GI endoscopy (UGIE) and to compare the lesions found in NSAID users and non-users.

METHODS

Participating gastroenterologists consecutively documented outpatients with and without suspicion of bleeding, referred for upper gastrointestinal endoscopy. Patient characteristics, presence of risk factors, NSAID use and endoscopic findings were reported on standard data collection forms.

MAIN RESULTS

A total of 2685 non-bleeding and 159 bleeding patients were enrolled within a time period of 2 months. NSAID therapy was present in 20% of the non-bleeding patients and at least 9% of referrals for endoscopy were directly related to suspected NSAID adverse events. Nearly half of acute bleeding patients (42%) were NSAID users, including aspirin for cardioprevention. Warning digestive symptoms prior to acute bleeding were frequently absent (56%). Oesophagitis was the main endoscopic diagnosis (51% of patients). Gastroduodenal (GD) ulcer was significantly more frequent in NSAID users, whereas oesophagitis and bleeding oesophageal varices were more frequent among non-users. Analysis of odds ratio's demonstrated NSAID use to significantly increase the risk for gastric ulcer in the whole patient group (OR = 2.73; 95% confidence interval (CI): 1.98-3.77; p < 0.001) and, in addition, for duodenal ulcer in the elderly (> 65 y) subgroup (OR = 2.91; 95% CI: 1.52-5.59; p < 0.05).

CONCLUSIONS

This survey confirms the high incidence of GD ulcers in NSAID users and the risk for serious gastrointestinal complications, often occurring without warning symptoms. It underlines the impact of NSAID use on the routine endoscopy load, the necessity of careful selection of patients for NSAID prescriptions and the need for gastropreventive measures, particularly in elderly patients and patients associating multiple risk factors.

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.

[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.

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.

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.

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.

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.

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.

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.

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.

[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.

Genetics of Crohn's disease behaviour

Crohn's disease is probably an heterogeneous entity. This heterogeneity may be linked to either genetics or environment. In particular the behaviour of the disease, i.e. the tendency to develop stricturing and/or penetrating lesions, may be linked to the genetic background. While epidemiological and clinical data suggest the relevance of these behavioural classifications, the progresses in the characterization of the immuno-inflammatory reaction in the bowel wall shed a new light on possible candidate genes for these genetic predispositions to various Crohn's disease behaviours. Association studies an linkage analysis focusing on growth factors, metalloproteinases and their tissue inhibitors as well as cytokines may bring new interesting data in this field.

[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.

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.

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.

Initial medical management of severe acute ulcerative colitis

Severe colitis is life-threatening complication of ulcerative colitis. Early recognition of the severity of the colitis, intensive medical therapy and prompt surgery when necessary have all contributed to improved outcome. Initial medical treatment should be instituted as soon as the diagnosis is made with an intravenous corticosteroid associated with supportive treatment. If the patient fails to response to this intensive treatment after 5-7 days, cyclosporin should be initiated. If cyclosporin is not used then colectomy should be performed immediately. Moreover, significant deterioration at any point during medical therapy is an indication for colectomy. The gravity of the patient's condition require close interaction between physician an surgeon.

[Guidelines for the management of Helicobacter pylori: recent opinion of the French National Society of Gastroenterology]

Guidelines for management of Helicobacter pylori are in constant evolution since its discovery in 1982 by Marshall and Warren. This article presents and comments recent guidelines developed under the auspices of the "Société Nationale Française de Gastroentérologie".

[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.

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.

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.

[Polyarteritis nodosa related to hepatitis b virus infection]

A 66-year-old man was hospitalized for asthenia, weight loss, fever and chills. A polyarteritis nodosa associated with hepatitis B virus infection in a replicative phase was diagnosed. Etiology, physiopathology, and clinical characteristics of hepatitis B virus-related polyarteritis nodosa will be reviewed, as well as the effectiveness of therapy combining corticosteroïds, interferon alpha and plasma exchanges.

Treatment of inflammatory bowel disease with azathioprine: how to use it in 1999

Azathioprine and 6-mercaptopurine are effective drugs in the management of steroid dependent and chronic active inflammatory bowel diseases. They are also well tolerated on the long term. However, their use is still hampered by some drawbacks including delay before efficacy, 20-35% of non responders, relapse at withdrawal of the drugs, possible bone marrow toxicity and other side effects. During the last few years, these drawbacks have been challenged by important studies showing that a better knowledge of the metabolism of these drugs may help to improve their use.

[Gastro-esophageal reflux and asthma]

Gastro-oesophageal reflux (GER) is more frequent in asthmatic patients than in the community at large. A causative association between the two diseases is suspected. Twenty-four hour ambulatory intraoesophageal pH monitoring represents the golden standard for the diagnosis of GER. The medical and/or surgical treatment of reflux in asthmatic patients with GER can improve pulmonary symptoms and to a lesser extent pulmonary function. The selection of the patients who will benefit from a GER treatment is difficult. Some symptoms like intrinsic asthma, nocturnal crises, could predict a good response to GER treatment.

Tumor necrosis factor alpha decreases, and interleukin-10 increases, the sensitivity of human monocytes to dexamethasone: potential regulation of the glucocorticoid receptor

Resistance to glucocorticoid therapy has been observed in patients with autoimmune/inflammatory diseases and may be related to the inflammatory process itself. The aim of this study was to examine the ability of tumor necrosis factor alpha (TNFalpha, a proinflammatory cytokine) and interleukin (IL)-10 (an anti-inflammatory cytokine) to differentially regulate the sensitivity of human monocytes/macrophages to glucocorticoids. To accomplish this, we first analyzed the pattern of TNFalpha and IL-10 inhibition by dexamethasone in LPS-stimulated whole-blood cell cultures. Second, we studied the modulation of the sensitivity of these cells to dexamethasone by preincubation with TNFalpha or IL-10 and measurement of LPS-stimulated IL-6 secretion. In addition, we evaluated the effect of dexamethasone on phorbolmyristate-acetate-stimulated IL-1 receptor antagonist secretion by the human monocytic cell line U937. Finally, we investigated whether the modulation of corticosensitivity in TNFalpha- and IL-10-pretreated U937 cells was related to a change of the glucocorticoid receptor concentration and affinity. Dexamethasone had different effects on LPS-induced TNFalpha and IL-10 secretion; whereas it suppressed TNFalpha in a dose-dependent fashion, its effect on IL-10 secretion was biphasic, producing stimulation at lower, and inhibition at higher doses. The concentration of LPS employed influenced the effect of dexamethasone on IL-10 secretion (P < 0.001). Pretreatment with TNFalpha diminished, and with IL-10 improved, the ability of dexamethasone to suppress IL-6 secretion in whole-blood cell cultures (P < 0.01 for both) and to enhance IL-1 receptor antagonist secretion by U937 cells (P < 0.05 for both). TNFalpha decreased (P < 0.001), while IL-10 increased (P < 0.001), the concentration of dexamethasone binding sites in these cells, with no discernible effect on their binding affinity. We conclude that glucocorticoids differentially modulate TNFalpha and IL-10 secretion by human monocytes in a LPS dose-dependent fashion and that the sensitivity of these cells to glucocorticoids is altered by TNFalpha or IL-10 pretreatment; TNFalpha blocks their effects, whereas IL-10 acts synergistically with glucocorticoids. This is accompanied by opposite glucocorticoid receptor changes, respectively opposing and favoring glucocorticoid actions. This study suggests that the pattern of pro-/antiinflammatory cytokine secretion may alter the response of patients to glucocorticoid therapy.

Acute lower gastrointestinal bleeding in Crohn's disease: characteristics of a unique series of 34 patients. Belgian IBD Research Group

OBJECTIVE

Acute lower gastrointestinal bleeding is a rare complication of Crohn's disease, which represents a diagnostic and therapeutic challenge. The aim of this study was to define epidemiological characteristics and therapeutic options of hemorrhagic forms of Crohn's disease.

METHODS

Thirty-four cases of hemorrhagic forms of Crohn's disease were studied retrospectively. Acute lower gastrointestinal hemorrhage was defined as acute rectal bleeding originating in diseased bowel and requiring a transfusion of at least 2 units of red blood cells within 24 h. Upper gastrointestinal tract hemorrhage or anal lesions and postoperative bleeding were excluded.

RESULTS

Mean age at time of hemorrhage was 34.2 +/- 14 yr. Mean duration of disease before the hemorrhage was 5.6 +/- 6 yr. The hemorrhage occurred during a flare up of the disease in 35% of cases. The hemorrhage revealed Crohn's disease in 23.5% of cases. The hemorrhage was more frequent in colonic disease (85%) than in isolated small bowel disease (15%) (p < 0.0001). The origin of bleeding was identified in 65% of cases, by colonoscopy (60%), by angiography (3 patients), or at surgery (1 patient). The bleeding lesion was an ulcer in 95% of cases, most often in the left colon. The treatment was surgical in 20.5% (colectomy in 36%), endoscopical (7 patients, including 5 successes), or medical. Hemorrhage recurred in 12 patients (35%) within a mean time of 3 yr (4 days-8 yr), requiring surgery in 3 cases. No death was observed.

CONCLUSIONS

This study performed in a series characterized by a nonsurgical recruitment, the largest to date, shows that hemorrhagic forms of Crohn's disease may reveal disease in 23.5%, occurs in quiescent Crohn's disease in two-thirds of cases. Given the potential efficacy of endoscopical or medical treatment, as well as the absence of mortality, a conservative approach may be suggested as first-line therapy in the majority of patients.

[Controversies in the treatment of Helicobacter pylori]

Helicobacter pylori is a worldwide infection. In gastro-duodenal ulcer disease no doubt remains about the necessity of H. pylori eradication. Controversies subsisting in other pathologies such gastro-esophageal reflux, dyspepsia, gastritis, gastric adenocarcinoma or MALT lymphoma are reviewed. Multiple drug combinations have been proposed to cure the infection. These are discussed in the clinical setting of Belgian practice.

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.

Use of the enteroscope for colo-ileoscopy: low yield in unexplained lower gastrointestinal bleeding

BACKGROUND AND STUDY AIMS

The small intestine is a potential origin of bleeding in patients with unexplained gastrointestinal tract hemorrhage or iron-deficiency anemia. Most reports on the investigation of these patients describe the use of upper tract enteroscopy. The diagnostic yield of combined upper and lower enteroscopy has not been widely assessed and remains to be clarified. The aim of this study was to assess the benefit of lower gastrointestinal tract enteroscopy in occult digestive bleeding.

PATIENTS AND METHODS

Between 1 December 1995 and 15 January 1998, 54 patients with gastrointestinal bleeding of unknown origin were prospectively studied using upper and lower video push enteroscopy (44 for chronic iron-deficiency anemia and 10 for unexplained gastrointestinal tract hemorrhage with no potential site having been identified by other investigations). Examinations were done using a Olympus video enteroscope (SIF-100) under general anesthesia in a one-day clinic. An upper tract examination was done first, directly followed by the lower tract investigation.

RESULTS

The upper tract enteroscopy was successful in 53 patients (98%) and retrograde ileoscopy in 21 patients (39%). In 18 (38%) cases the technical failure resulted from the impossibility of intubating the ileocecal valve. A potential source of upper gastrointestinal bleeding was detected in 35% of patients with chronic iron-deficiency anemia and in 20% of those with unexplained gastrointestinal tract hemorrhage. The most common lesion in the small bowel was angiodysplasia (25%). The lower tract video push enteroscopy disclosed 11 lesions in patients with chronic anemia. However the lesions, including two ileocecal valve cancers, were mainly located in the colon and had been missed by previous colonoscopy. No case of ileal lesion was detected in this group of patients. In patients with unexplained gastrointestinal tract hemorrhage, three lesions were detected but only one of these was in the ileum. Associated colonic and jejunal lesions were observed in three patients (5.5%). Overall, the diagnostic yield of lower video push enteroscopy was less than 2%.

CONCLUSION

This prospective study has shown that using an enteroscope as a colonoscope in the management of patients with gastrointestinal bleeding of unknown origin is of little help. It might actually be more appropriate to perform a second colonoscopy. This however remains controversial and a prospective study is needed to answer that question.

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.

Clinical pattern of corticosteroid dependent Crohn's disease

OBJECTIVES

Corticosteroid dependency in Crohn's disease (CD) is characterized by the need for chronic use of corticosteroids to maintain clinical remission. Several definitions have been used. Depending on the definition, 10-30% of the patients are considered as corticosteroid dependent. The aim of the study was to define a clinical pattern of corticosteroid dependent CD patients.

PATIENTS AND METHODS

Epidemiological and clinical characteristics were retrospectively compared between 20 corticosteroid dependent CD patients and 248 non-corticosteroid dependent CD patients by using univariate and multivariate analyses. Corticosteroid dependency was defined either by two successive relapses during the 2 months after discontinuing glucocorticoids (n=5) or by two successive relapses at dose tapering, after successful treatment of a flare-up by using glucocorticoids (n=15).

RESULTS

Corticosteroid dependent CD patients were younger at diagnosis (P < 0.001), and were characterized by a higher frequency of colonic location (P< 0.05), but lower frequency of ileal location (P < 0.01), and higher ano-perineal location (P < 0.05). They were also more frequently smokers (P< 0.05) and users of contraceptive pills (P< 0.01). The inflammatory type of the disease was increased (P < 0.01), while the fibrostenotic type was decreased (P < 0.001) in corticosteroid dependent CD patients. By multivariate analysis, a smoking habit (P < 0.01), a colonic location (P < 0.05), a non-fibrostenotic type (P< 0.05) and a younger age at diagnosis (P< 0.05) were shown to be independently associated with corticosteroid dependency.

CONCLUSIONS

This study suggests a clinical pattern associated with corticosteroid dependency. Whether this clinical pattern is simply associated with the dependency, or whether a primary decrease of corticosensitivity produces this clinical pattern, is not known. Further prospective studies will have to determine whether the presence of these clinical characteristics is predictive of corticosteroid dependency and whether this prediction will be useful for the management of this condition.

Incidence of inflammatory bowel disease in the area of Liège: a 3 years prospective study (1993-1996)

A first prospective epidemiological study of IBD was conducted in the area of Liège. The duration of the study was short taking into account the small size of the population (1 million inhabitants). Therefore we carried out a 3 years prospective study.

METHOD

Private and public gastroenterologists completed a questionnaire for each new case they diagnosed between 01.06.1993 and 31.05.1996.

RESULTS

During that period 270 IBD patients were identified: 137 (51%) had Crohn's disease (CD), 111 (41%) had ulcerative colitis (UC) including 32 proctitis (29% of UC) and 22 (8%) had unclassified colitis. The mean annual incidence per 10(5) was 4.5 for CD and 3.6 for UC. The female/male ratio was 1,6 for CD and 0,5 for UC. The median age at the time of diagnosis was 30 years for CD and 39 years for UC. The mean time between the onset of symptoms and the diagnosis was 6,5 months for CD and only 4,8 months for UC. Family history of IBD was found in 15% of patients with CD and in 7% of UC.

CONCLUSIONS

These data show a high incidence of IBD in the area of Liege. These results confirm those reported during the first year of the prospective study which were similar to those observed in North-western France. Contrary to the other countries of Northern Europe, the incidence of UC is lower than the one of CD. Belgium appears to be a privileged country to undertake a national register and to study epidemiological aspects of IBD.

Tumour necrosis factor (TNF) gene polymorphism influences TNF-alpha production in lipopolysaccharide (LPS)-stimulated whole blood cell culture in healthy humans

TNF-alpha is involved in infectious and immuno-inflammatory diseases. Different individuals may have different capacities for TNF-alpha production. This might determine a predisposition to develop some complications or phenotypes of these diseases. The aims of our study were to assess the inter-individual variability of TNF-alpha production and to correlate this variability to a single base pair polymorphism located at position -308 in TNF gene. We studied 62 healthy individuals. TNF-alpha production after LPS stimulation was evaluated using a whole blood cell culture model. The TNF gene polymorphism was studied by an allele-specific polymerase chain reaction. Other cytokines produced in the culture, soluble CD14 concentrations and expression of CD14 on blood cells were also measured. Among the 62 individuals, 57 were successfully genotyped. There were 41 TNF1 homozygotes and 16 TNF1/TNF2 heterozygotes. TNF-alpha production after LPS stimulation of whole blood cell culture was higher among TNF2 carriers than among TNFI homozygotes (929pg/ml (480-1473pg/ml) versus 521 pg/ ml (178-1307 pg/ml); P<0.05). This difference was even more significant after correction of TNF-alpha production for CD14 expression on blood cells. In conclusion, the single base pair polymorphism at position -308 in the TNF gene may influence TNF-alpha production in healthy individuals.

[Clinical case of the month. Hepatoportal sclerosis in a patient treated with azathioprine]

We report a case of hepatoportal sclerosis in a renal transplant patient treated with azathioprine. The initial symptom was ascites. On the biochemical level, there were cholestasis without cytolysis or hepatocellular insufficiency. A presinusoidal portal hypertension was found on haemodynamic studies, without portal thrombosis at CT-scan. A diagnosis of hepatoportal sclerosis was evoked on histology and attributed to azathioprine. This case gives an illustration of a classical albeit rare complication of azathioprine. The indolent pattern of the disease and the risk of variceal bleeding point out the need for a hepatic follow-up during the treatment.

Extensive ulcerative colitis and extraintestinal manifestations in a patient with HIV infection and significant CD4 T-cell lymphopenia

We report a heterosexual patient with HIV infection and a CD4 T-cell count of 0.45 x 10(9)/L who developed mild ulcerative proctitis, sacroileitis and oligoarthiritis. While he was treated with 5-aminosalicylic enemas, the patient rapidly developed severe pancolitis. An emergency colectomy without procetectomy was performed. A few months later, he suffered recurrence of ulcerative proctitis, aggravation of arthritic pain and developed anterior uveitis. All symptoms disappeared after proctectomy. There was no evidence for opportunistic infection or Kaposi's sarcoma. Antineutrophil cytoplasmic antibodies were positive and the HLA-B27 antigen was present. CD4 counts were lower during the phases of active disease than during remission. This case demonstrates that severe ulcerative colitis can occur in the presence of moderate T-cell defects. In view of a recent report of remission of Crohn's disease under comparable circumstances, it is possible that the extent of T-cell involvement in both diseases is radically different.

Corticosteroid treatment in active Crohn's disease

Despite recent improvements in the management of Crohn's disease, steroids are still the most efficacious treatment in flare ups of the disease. However they have significant side effects and are only effective in the short term. There is no consensus regarding initial dose or duration of corticotherapy. With 1 mg/Kg a day of oral prednisolone given for 3 to 7 weeks, 92% of the patients achieve clinical remission. Topical acting oral corticosteroids such as budesonide seem to represent an important therapeutic advance due to their better tolerance. The promising results of budesonide in mild and moderate flare ups need to be confirmed and its indication in severe disease beside high dose prednisolone has to be clarified.

[Pseudo-alcoholic hepatitis and cirrhosis caused by amiodarone (Cordarone)]

Amiodarone is an antiarrhythmic drug widely used to treat a variety of supraventricular and ventricular arrhythmias. However its drawback is a very slow elimination and very frequent adverse effects (thyroid, pulmonary, neurologic, ocular, dermatologic, hepatic disorders). We describe a patient who developed a pseudoalcoholic liver disease and a cirrhosis after use of Amiodarone for a long period of time.

Effects of dexamethasone on the profile of cytokine secretion in human whole blood cell cultures

EXPERIMENTAL OBJECTIVES

The interaction between the endocrine and immune systems is a very intriguing area. Endogenous glucocorticoids, as end-effectors of the hypothalamo-pituitary-adrenal axis, inhibit the immune and inflammatory responses and are used as immunosuppressive drugs in many inflammatory, autoimmune and allergic diseases. The aims of this study were to investigate the effects of dexamethasone on the profile of cytokine secretion in whole blood cell cultures from healthy subjects and to analyse the gender-related sensitivity to dexamethasone on each cytokine secretion.

RESULTS

There was a significant inhibition by dexamethasone (from 1 to 100 nM) on the secretion of monokines (IL-1beta, IL-6, IL-8 and TNF alpha) and lymphokines (IL-2, IL-4, IL-10 and IFN gamma), either after LPS or PHA stimulation (P < 0.01). Interleukin 4 and IL-10 were less inhibited than IFN gamma (P < 0.05 at 1 nM, P < 0.01 at 10 nM and P < 0.001 from 100 nM to 10 microM). No gender difference was observed in the rate of inhibition of the secretion of each cytokine.

CONCLUSION

This study shows that the inhibition of cytokine secretion by dexamethasone is more marked on Th1-type cytokines than on Th2-type cytokines. These data support the idea that glucocorticoids may induce a shift from the Th1 to Th2 profile of cytokine secretion.

[Corticosteroid sensitivity, dependence and resistance in inflammatory and immunologic diseases. Physiopathologic review]

Patients suffering from inflammatory or dysimmunitary diseases may develop various clinical responses to corticotherapy. This brief article describes the various cellular and molecular mechanisms which underly the genetic, endocrine and immunitary factors involved in corticosensitivity, corticoresistance and corticodependence.

Association between myelodysplastic syndromes and inflammatory bowel diseases. Report of seven new cases and review of the literature

We report seven patients with both myelodysplastic syndrome (MDS) and inflammatory bowel disease (IBD): Crohn's disease in six cases, ulcerative colitis in one case. We describe their characteristics, and those of 10 previously published similar cases are presented here. Median age at diagnosis of IBD (61 years) was high, as compared to the usual age at diagnosis of IBD. IBD was diagnosed first in nine cases, MDS first in one patient, and both diseases were diagnosed simultaneously in seven cases. Concerning IBD, there was a strong predominance of Crohn's disease (15/17 cases), with an unusually high frequency of colonic involvement (11/15 cases). MDS, in 12/17 cases, showed no excess of marrow blasts. Cytogenetic analysis was abnormal in five of the 13 evaluable cases. These observations suggest that the association between MDS and IBD may not be fortuitous in some cases, and that, in particular, patients with IBD and anemia of nonobvious origin should be evaluated for MDS. The pathogenesis of those associations, however, remains unclear.

A high serum concentration of interleukin-6 is predictive of relapse in quiescent Crohn's disease

BACKGROUND/AIMS

Relapses of Crohn's disease are difficult to predict. We assessed the value of serum level of interleukin-6, tumour necrosis factor alpha (TNF-alpha) and soluble TNF receptors as predictors of relapse in quiescent Crohn's disease.

PATIENTS/METHODS

Thirty-six patients with inactive Crohn's disease, treated or not, were included. Various clinical and biological parameters, including interleukin-6, TNF-alpha and soluble TNF receptors serum levels were measured at inclusion in the study and the patients were followed clinically for 1 year. The relapse was defined as a Crohn's Disease Activity Index (CDAI) greater than 150 with an increase greater than 100 compared to the inclusion value. We analysed the ability of these parameters to predict relapse in parallel to clinical characteristics and other laboratory parameters.

RESULTS

Among the 32 variables tested, interleukin-6 serum level had the greatest ability to predict the time-to-relapse, with 17-fold chance of relapse over a 1-year period for patients with an interleukin-6 serum level greater than 20 pg/ml than for patients with a lower level (P < 0.001). A high serum level of the soluble TNF receptors p55 and p75 also had significant predictive value, in contrast to TNF-alpha serum levels. An interleukin-6 serum level greater than 20 pg/ml and either an acid alpha-1-glycoprotein level greater than 1.1 g/l or a soluble interleukin-2 receptor serum level greater than 95 pM/l were risk factors selected by a stepwise multivariate analysis. In both models a good prognosis group was defined by the absence of the two risk factors, a bad prognostic group by the presence of the two risk factors and an intermediate in between. With both models, the good prognosis group included 17 patients who experienced no relapse over the 1-year follow-up, whereas all patients (seven with the first model and six with the second) in the bad prognosis group had a relapse during the follow-up. Looking specifically at two homogeneous subgroups including either naturally/5-aminosalicylic acid (5-ASA) quiescent or corticoid quiescent patients, a very good predictive value for interleukin-6 serum concentration was also found.

CONCLUSION

Interleukin-6 serum level alone or in association with other biological parameters such as acid alpha-1-glycoprotein or the soluble interleukin-2 receptor serum level may be useful for predicting the course of the disease in patients with quiescent Crohn's disease.