Exome-Wide Association Study Identifies New Low-Frequency and Rare UGT1A1 Coding Variants and UGT1A6 Coding Variants Influencing Serum Bilirubin in Elderly Subjects: A Strobe Compliant Article

Genome-wide association studies (GWASs) have identified loci contributing to total serum bilirubin level. However, no exome-wide approaches have been performed to address this question. Using exome-wide approach, we assessed the influence of protein-coding variants on unconjugated, conjugated, and total serum bilirubin levels in a well-characterized cohort of 773 ambulatory elderly subjects from Italy. Coding variants were replicated in 227 elderly subjects from the same area. We identified 4 missense rare (minor allele frequency, MAF < 0.5%) and low-frequency (MAF, 0.5%-5%) coding variants located in the first exon of the UGT1A1 gene, which encodes for the substrate-binding domain (rs4148323 [MAF = 0.06%; p.Gly71Arg], rs144398951 [MAF = 0.06%; p.Ile215Val], rs35003977 [MAF = 0.78%; p.Val225Gly], and rs57307513 [MAF = 0.06%; p.Ser250Pro]). These variants were in strong linkage disequilibrium with 3 intronic UGT1A1 variants (rs887829, rs4148325, rs6742078), which were significantly associated with total bilirubin level (P = 2.34 × 10(-34), P = 7.02 × 10(-34), and P = 8.27 × 10(-34)), as well as unconjugated, and conjugated bilirubin levels. We also identified UGT1A6 variants in association with total (rs6759892, p.Ser7Ala, P = 1.98 × 10(-26); rs2070959, p.Thr181Ala, P = 2.87 × 10(-27); and rs1105879, p.Arg184Ser, P = 3.27 × 10(-29)), unconjugated, and conjugated bilirubin levels. All UGT1A1 intronic variants (rs887829, rs6742078, and rs4148325) and UGT1A6 coding variants (rs6759892, rs2070959, and rs1105879) were significantly associated with gallstone-related cholecystectomy risk. The UGT1A6 variant rs2070959 (p.Thr181Ala) was associated with the highest risk of gallstone-related cholecystectomy (OR, 4.58; 95% CI, 1.58-13.28; P = 3.21 × 10(-3)). Using an exome-wide approach we identified coding variants on UGT1A1 and UGT1A6 genes in association with serum bilirubin level and hyperbilirubinemia risk in elderly subjects. UGT1A1 intronic single-nucleotide polymorphisms (SNPs) (rs6742078, rs887829, rs4148324) serve as proxy markers for the low-frequency and rare UGT1A1 variants, thereby providing mechanistic explanation to the relationship between UGT1A1 intronic SNPs and the UGT1A1 enzyme activity. UGT1A1 and UGT1A6 variants might be potentially associated with gallstone-related cholecystectomy risk.

A non-synonymous polymorphism in galectin-3 lectin domain is associated with allergic reactions to beta-lactam antibiotics

Genetic predictors of beta-lactam (BL) allergy are mostly related to Immunoglobulin E (IgE) synthesis and atopy. Despite this context, little attention has been devoted to genes of IgE/FcɛRI pathway, such as galectin-3, a β-galactoside-binding lectin, which binds to IgE. We evaluated the association of LGALS3 polymorphisms with BL allergy in 395 Spanish and 198 Italian cases, compared with 310- and 339-matched controls, respectively. The rs11125 predicted BL allergy with an odds ratio of 4.0 in Spanish population (P<0.0001). This association was replicated with an odds ratio of 5.1 in Italian population (P<0.0001); rs11125 predicted also increased serum level of total IgE in Spanish controls. These data are consistent with the predicted deleterious influence of Gln>His substitution produced by rs11125 on galactose-binding activity of galectin-3. In conclusion, LGALS3 is the strongest genetic predictor of BL allergy reported so far. This association reflects the influence of genes of IgE/FcɛRI pathway in this pathology.

Information-seeking behavior during residency is associated with quality of theoretical learning, academic career achievements, and evidence-based medical practice: a strobe-compliant article

Data regarding knowledge acquisition during residency training are sparse. Predictors of theoretical learning quality, academic career achievements and evidence-based medical practice during residency are unknown. We performed a cross-sectional study on residents and attending physicians across several residency programs in 2 French faculties of medicine. We comprehensively evaluated the information-seeking behavior (I-SB) during residency using a standardized questionnaire and looked for independent predictors of theoretical learning quality, academic career achievements, and evidence-based medical practice among I-SB components using multivariate logistic regression analysis. Between February 2013 and May 2013, 338 fellows and attending physicians were included in the study. Textbooks and international medical journals were reported to be used on a regular basis by 24% and 57% of the respondents, respectively. Among the respondents, 47% refer systematically (4.4%) or frequently (42.6%) to published guidelines from scientific societies upon their publication. The median self-reported theoretical learning quality score was 5/10 (interquartile range, 3-6; range, 1-10). A high theoretical learning quality score (upper quartile) was independently and strongly associated with the following I-SB components: systematic reading of clinical guidelines upon their publication (odds ratio [OR], 5.55; 95% confidence interval [CI], 1.77-17.44); having access to a library that offers the leading textbooks of the specialty in the medical department (OR, 2.45, 95% CI, 1.33-4.52); knowledge of the specialty leading textbooks (OR, 2.12; 95% CI, 1.09-4.10); and PubMed search skill score ≥5/10 (OR, 1.94; 95% CI, 1.01-3.73). Research Master (M2) and/or PhD thesis enrolment were independently and strongly associated with the following predictors: PubMed search skill score ≥5/10 (OR, 4.10; 95% CI, 1.46-11.53); knowledge of the leading medical journals of the specialty (OR, 3.33; 95% CI, 1.32-8.38); attending national and international academic conferences and meetings (OR, 2.43; 95% CI, 1.09-5.43); and using academic theoretical learning supports several times a week (OR, 2.23; 95% CI, 1.11- 4.49). This study showed weaknesses in the theoretical learning framework during residency. I-SB was independently associated with quality of academic theoretical learning, academic career achievements, and the use of evidence-based medicine in everyday clinical practice.

STUDY REGISTRATION

CNIL No.1797639.

CARM1 and PRMT1 are dysregulated in lung cancer without hierarchical features

CARM1 and PRMT1 are 2 Protein Arginine Methyl Transferases (PRMT) dysregulated in cancer. CARM1 function is contradictory and depicted as facilitating proliferation or differentiation. PRMT1 is required for cell proliferation. CARM1 and PRMT1 cooperate for gene regulation. We report that CARM1 and PRMT1 are significantly overexpressed in 60 patients with Non-Small Cell Lung Carcinomas (NSCLC). CARM1 and PRMT1 correlated in healthy but not tumor tissue. Their levels of expression in tumor tissue were proportional to their levels of expression in the counterpart healthy tissue. Only CARM1 expression was found to be correlated with tumor differentiation and neither CARM1 nor PRMT1 expression was correlated with survival. Accordingly, CARM1 and PRMT1 are overexpressed in 2 NSCLC cell lines, A549 and H1299. Targeting PRMT1 with siRNA reduced proliferation, by decreasing cell growth and inhibiting soft agar colony formation, and promoted differentiation, by increasing the epithelial markers cytokeratin 7 and 8 and decreasing Neuromedin B receptor, which binds a mitogenic factor. siCARM1 yielded similar consequences but the conditions with siCARM1 reflected inhibition of both CARM1 and PRMT1. Together these results suggest that CARM1 and PRMT1 are involved in proliferation in lung cancer with no hierarchy of one protein over the other. The fact that CARM1 targeting suppresses PRMT1 in addition to CARM1 reinforces the functional importance of CARM1/PRMT1 interaction.

Allergy to betalactams and nucleotide-binding oligomerization domain (NOD) gene polymorphisms

BACKGROUND

Polymorphisms of interleukin genes related to IgE production and inflammation are predictors of hypersensitivity to betalactam, but nothing is known on the influence of NOD genes, despite their association with inflammation and atopy.

OBJECTIVE

To evaluate the association of NOD2 and NOD1 polymorphisms with betalactam allergy.

METHOD

We genotyped 3 polymorphisms of NOD2 and 1 of NOD1 in 368 Italian and 387 Spanish patients, compared with 368 and 326 controls, respectively.

RESULTS

CT/TT genotypes of rs2066845 of NOD2 predicted a lower risk in Italy (P = 0.003), while WT/insC genotype of rs5743293 (also in leucine-rich repeat domain) predicted a higher risk in Spain (P = 0.007). G allele of rs2066845 was associated with a higher level of IgE in the Italian population.

CONCLUSION

The mirrored influence of these NOD2 polymorphisms on betalactam allergy in two populations suggests a link with pathways of inflammation and/or atopy through mechanisms, which need to be clarified.

Gastric intrinsic factor deficiency with combined GIF heterozygous mutations and FUT2 secretor variant

Several genome-wide association studies (GWAS) have identified a strong association between serum vitamin B12 and fucosyltransferase 2 (FUT2), a gene associated with susceptibility to Helicobacter pylori infection. Hazra et al. conducted a meta-analysis of three GWAS and found three additional loci in MUT, CUBN and TCN1. Other GWAS conducted in Italy and China confirmed the association for FUT2 gene. Alpha-2-fucosyltransferase (FUT2) catalyzes fucose addition to form H-type antigens in exocrine secretions. FUT2 non-secretor variant produces no secretion of H-type antigens and is associated with high-plasma vitamin B12 levels. This association was explained by the influence of FUT2 on H. pylori, which is a risk factor of gastritis, a main cause of vitamin B12 impaired absorption. However, we recently showed that H. pylori serology had no influence on FUT2 association with vitamin B12, in a large sample population, suggesting the involvement of an alternative mechanism. GIF is another gene associated with plasma levels of vitamin B12 and gastric intrinsic factor (GIF) is a fucosylated protein needed for B12 absorption. Inherited GIF deficiency produces B12 deficiency unrelated with gastritis. We report 2 families with heterozygous GIF mutation, 290T>C, M97T, with decreased binding affinity of GIF for vitamin B12 and one family with heterozygous GIF mutation 435_437delGAA, K145_N146delinsN and no B12 binding activity of mutated GIF. All cases with vitamin B12 deficit carried the FUT2 rs601338 secretor variant. Ulex europeus binding to GIF was influenced by FUT2 genotypes and GIF concentration was lower, in gastric juice from control subjects with the secretor genotype. GIF290C allele was reported in 5 European cases and no Africans among 1282 ambulatory subjects and was associated with low plasma vitamin B12 and anaemia in the single case bearing the FUT2 secretor variant. We concluded that FUT2 secretor variant worsens B12 status in cases with heterozygous GIF mutations by impairing GIF secretion, independently from H. pylori-related gastritis.

Incidence of and impact of medications on colectomy in newly diagnosed ulcerative colitis in the era of biologics

BACKGROUND

The cumulative incidence of colectomy and the impact of 5-aminosalicylates (5-ASA), azathioprine, and antitumor necrosis factor (TNF) treatment on the long-term need for surgery are unknown in ulcerative colitis (UC) in the era of biologics.

METHODS

This was an observational study of a referral center cohort. The cumulative incidence of UC-related colectomy was estimated using the Kaplan-Meier method. Independent predictors of surgery were identified using Cox proportional hazards regression with propensity scores adjustment. The electronic charts of 151 incident cases of UC from Nancy University Hospital, France, diagnosed between 2000 and 2008, were reviewed through January 2010.

RESULTS

The median follow-up time per patient was 58 months. Twenty-one (14%) underwent surgery. The cumulative probabilities of colectomy were respectively 1.3% and 13.5% at 1 and 5 years from the time of diagnosis. The probability of receiving oral mesalamine at 5 years was 68.1%. The corresponding figures were 48.9% for azathioprine and 29.0% for infliximab. For corticosteroids, methotrexate, and cyclosporin these figures were 75%, 8.8%, and 11.5%, respectively. Using multivariate Cox proportional hazards regression analysis after propensity score adjustment, previous use of cyclosporin was the only independent predictor for colectomy (hazard ratio = 4.41; 95% confidence interval 1.75-1.13).

CONCLUSIONS

About one-tenth of patients still require colectomy for UC at 5 years in the era of biologics. Oral 5-ASA, azathioprine, and anti-TNF therapy are not associated with a reduced need for colectomy.

Plasma soluble triggering receptor expressed on myeloid cells-1 in Crohn's disease

BACKGROUND

No definite conclusions can be drawn from available data on the accuracy of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) to assess disease activity in Crohn's disease.

AIMS

Plasma sTREM-1 levels were correlated with disease activity markers in Crohn's disease.

METHODS

191 consecutive patients from a single referral centre (Nancy IBD cohort) were prospectively enrolled between June 1, 2005 and December 12, 2008. Plasma sTREM-1 levels were also assessed amongst 20 healthy controls.

RESULTS

The sTREM-1 was detectable in 87 Crohn's disease patients (46%). Plasma sTREM-1 level was higher in Crohn's disease patients (interquartile range, 0-356) than in healthy controls (interquartile range, 0-15.1; P=0.01). It was neither correlated with Crohn's disease activity index (r=0.05, P=0.56), C-reactive protein (r=0.06, P=0.53), nor with albumin (r=-0.041, P=0.66). Crohn's disease activity index, C-reactive protein and albumin median levels were similar between patients with positive sTREM-1 levels and those with undetectable sTREM-1 levels. Azathioprine (P=0.06), infliximab (P=0.68) and methotrexate (P=0.56) did not influence sTREM-1 levels.

CONCLUSION

Plasma sTREM-1 does not appear to be an accurate marker of disease activity in Crohn's disease and cannot be recommended for assessing disease activity in these patients.

Urinary tract infections in hospitalized inflammatory bowel disease patients: a 10-year experience

BACKGROUND

Cystitis is the most common genitourinary complication in Crohn's disease (CD). We assessed the prevalence of and risk factors for urinary tract infections (UTI) in inflammatory bowel diseases (IBD).

METHODS

Among the 1173 IBD patients of the "Nancy IBD cohort" seen between January 1, 2000 and December 31, 2009, 56 hospitalized patients had 76 documented UTI. Prevalence of UTI in IBD was calculated using rates of UTI among non-IBD patients hospitalized during the same period. The cases were compared to 175 matched IBD patients without UTI hospitalized during the same period to identify risk factors for UTI.

RESULTS

Prevalence of UTI was 4% in IBD patients versus 3.3% in non-IBD patients (P = 0.1). Prevalence of UTI was 4.5% and 2.1% in ulcerative colitis (UC) and CD patients, respectively (P = 0.6). Risk factors for UTI in CD patients were perianal disease (odds ratio [OR] = 2.28, 95% confidence interval [CI], 1.06-4.89; P = 0.04) and colonic disease (OR = 2.42, 95% CI, 1.05-5.58; P = 0.04). Male gender (OR = 0.38, 95% CI, 0.17-0.85, P = 0.02) and noncomplicated behavior (OR = 0.26, 95% CI, 0.11-0.60, P = 0.002) were protective factors against UTI in CD. In UC patients, age over 40 years (OR = 9.59, 95% CI, 1.93-47.74; P = 0.006) and disease duration over 11 months (OR = 10.77, 95% CI, 1.68-68.89, P = 0.01) were risk factors for UTI. Male gender was negatively associated with UTI (OR = 0.04, 95% CI, 0.01-0.36, P = 0.00006).

CONCLUSIONS

Hospitalized IBD patients are not at increased risk of UTI. Risk factors for UTI include perianal disease and colonic disease in CD and age and longer disease duration in UC.

Helicobacter pylori serologic status has no influence on the association between fucosyltransferase 2 polymorphism (FUT2 461 G->A) and vitamin B-12 in Europe and West Africa

BACKGROUND

Genomewide association studies have shown a relation between plasma vitamin B-12 concentration and the 461G→A polymorphism of fucosyltransferase 2 (FUT2), a gene associated with susceptibility to Helicobacter pylori infection.

OBJECTIVE

We evaluated in 2 populations the association of FUT2 461 G→A polymorphism with vitamin B-12 and related metabolic markers and investigated whether the influence of FUT2 on H. pylori serology is part of the mechanisms that underlie these associations.

DESIGN

The study included 1282 ambulatory subjects from Europe and West Africa. Blood concentrations of vitamin B-12, folate, homocysteine, and methylmalonic acid were measured. Genotyping was performed by real-time polymerase chain reaction. H. pylori serology testing was performed by using ELISA.

RESULTS

In univariate analysis, FUT2 461 A/A genotype was associated with higher plasma vitamin B-12 concentration in the total population (P = 0.0007) as well as in Europe (P = 0.0009) and in West Africa (P = 0.0015). Positivity for H. pylori serology was higher in West Africa (P < 0.0001) and was not associated with low plasma vitamin B-12. The prevalence of H. pylori-positive patients did not differ among FUT2 461 G→A genotypes (P = 0.2068). In multivariate analysis, FUT2 461 G→A genotype (P = 0.0008), but not positive H. pylori serology, was an independent predictor of plasma vitamin B-12 concentration.

CONCLUSION

This study confirms the influence of FUT2 461 G→A polymorphism on plasma vitamin B-12 concentration and showed no influence of H. pylori serologic status on this association in ambulatory subjects from Europe and West Africa.

Use of thiopurine testing in the management of inflammatory bowel diseases in clinical practice: a worldwide survey of experts

BACKGROUND

We performed a worldwide survey to evaluate the extent to which gastroenterologists who are experts in the field of inflammatory bowel diseases (IBDs) are utilizing thiopurine metabolism in practice.

METHODS

This was a Web-based cross-sectional survey consisting of 12 multiple-choice and open-ended questions.

RESULTS

Between December 2009 and April 2010, 175 questionnaires were received. The proportion of practitioners with access and reimbursement for thiopurine S-methyltransferase (TPMT) genotype, TPMT phenotype, 6-thioguanine nucleotides (6-TGN) levels, and 6-methylmercaptopurine ribonucleotides (6-MMP) levels was 48%, 54%, 44%, and 35%, respectively. Before azathioprine initiation, TPMT genotype and phenotype were performed by only 30% and 43% of responders, respectively. In patients on thiopurine therapy, 6-TGN and 6-MMP levels were determined by 54% and 44% of responders, respectively. Only 27% of physicians always wait for TMPT activity/genotype results before initiating azathioprine and 81% do not routinely recheck metabolite levels after dose escalation or reduction. In cases of very high or low TPMT activity, 75% and 74% of practitioners take into account TMPT activity result, respectively. If access to all azathioprine metabolite measurements was available and if all these tests were reimbursed by public health insurance, 47% of responders would use these tests more often in their practice. The availability and reimbursement of TPMT status and azathioprine metabolites strongly influenced experts' attitudes.

CONCLUSIONS

Thiopurine testing is relatively underutilized by IBD gastroenterologists. The availability and reimbursement of TPMT status and azathioprine metabolites strongly influence the management of IBD patients treated with thiopurines.

Meta-analysis: hyperhomocysteinaemia in inflammatory bowel diseases

BACKGROUND

The magnitude of association between homocysteine metabolism and inflammatory bowel diseases (IBD) remains unknown, whereas the association between hyperhomocysteinaemia and thrombosis remains controversial in IBD.

AIM

To conduct a systematic review and meta-analysis to examine these issues.

METHODS

The literature search was conducted using MEDLINE database and international conference abstracts from January 1966 to April 2011 and included all studies that evaluated plasma homocysteine level in IBD.

RESULTS

Twenty-eight studies evaluated the plasma homocysteine level and/or hyperhomocysteinaemia risk in IBD patients. Five studies assessed the association of hyperhomocysteinaemia with thrombosis. The mean plasma homocysteine level was significantly higher in IBD patients when compared with controls (weighted mean difference (WMD)=3.75 μmol/L; 95% CI, 2.23-5.26 μmol/L; P<0.0001; reference ranges for plasma homocysteine level: 5-12 μmol/L). The mean plasma homocysteine level did not differ between ulcerative colitis (UC) and Crohn's disease (CD) (WMD=0.41 μmol/L; 95% CI, -2.45 to 3.06 μmol/L; P=0.76). The risk of hyperhomocysteinaemia was significantly higher in IBD patients when compared with controls [odds ratio (OR)=4.65; 95% CI, 3.04-7.09; P<0.0001]. The risk of hyperhomocysteinaemia was not higher among IBD patients who experienced thromboembolic complications (OR=1.97; 95% CI, 0.83-4.67; P=0.12). Plasma folate level was inversely correlated with IBD risk associated with MTHFR C677T polymorphism (P=0.006).

CONCLUSIONS

The risk of hyperhomocysteinaemia is significantly higher in IBD patients when compared with controls. The risk assessment of hyperhomocysteinaemia-related thrombosis in IBD requires further investigation. Deficient folate status is associated with a higher impact of MTHFR C677T polymorphism on IBD risk.

Meta-analysis: hyperhomocysteinaemia in inflammatory bowel diseases

BACKGROUND

The magnitude of association between homocysteine metabolism and inflammatory bowel diseases (IBD) remains unknown, whereas the association between hyperhomocysteinaemia and thrombosis remains controversial in IBD.

AIM

To conduct a systematic review and meta-analysis to examine these issues.

METHODS

The literature search was conducted using MEDLINE database and international conference abstracts from January 1966 to April 2011 and included all studies that evaluated plasma homocysteine level in IBD.

RESULTS

Twenty-eight studies evaluated the plasma homocysteine level and/or hyperhomocysteinaemia risk in IBD patients. Five studies assessed the association of hyperhomocysteinaemia with thrombosis. The mean plasma homocysteine level was significantly higher in IBD patients when compared with controls (weighted mean difference (WMD)=3.75 μmol/L; 95% CI, 2.23-5.26 μmol/L; P<0.0001; reference ranges for plasma homocysteine level: 5-12 μmol/L). The mean plasma homocysteine level did not differ between ulcerative colitis (UC) and Crohn's disease (CD) (WMD=0.41 μmol/L; 95% CI, -2.45 to 3.06 μmol/L; P=0.76). The risk of hyperhomocysteinaemia was significantly higher in IBD patients when compared with controls [odds ratio (OR)=4.65; 95% CI, 3.04-7.09; P<0.0001]. The risk of hyperhomocysteinaemia was not higher among IBD patients who experienced thromboembolic complications (OR=1.97; 95% CI, 0.83-4.67; P=0.12). Plasma folate level was inversely correlated with IBD risk associated with MTHFR C677T polymorphism (P=0.006).

CONCLUSIONS

The risk of hyperhomocysteinaemia is significantly higher in IBD patients when compared with controls. The risk assessment of hyperhomocysteinaemia-related thrombosis in IBD requires further investigation. Deficient folate status is associated with a higher impact of MTHFR C677T polymorphism on IBD risk.

Cytomegalovirus load in inflamed intestinal tissue is predictive of resistance to immunosuppressive therapy in ulcerative colitis

OBJECTIVES

Previous studies have suggested an association between cytomegalovirus (CMV) infection and steroid-refractory inflammatory bowel disease. In this study, the use of CMV DNA load during acute flare-ups of ulcerative colitis (UC) to predict resistance to immunosuppressive therapy was evaluated in intestinal tissue.

METHODS

Forty-two consecutive patients (sex ratio M/F: 0.9, mean age: 43.6 years) hospitalized for moderate to severe UC and treated with IV steroids were included prospectively. A colonoscopy was performed for each patient at inclusion; colonic biopsy samples of the pathological tissue, and if possible, of the healthy mucosa, were tested for histological analysis and determination of CMV DNA load by real-time polymerase chain reaction assay. Patients were treated as recommended by the current guidelines.

RESULTS

Sixteen patients were found positive for CMV DNA in inflamed intestinal tissue but negative in endoscopically healthy tissue; all of these patients were positive for anti-CMV IgG, three exhibited CMV DNA in blood, and none was positive for intestinal CMV antigen by immunohistochemistry detection. In the 26 remaining patients, no stigmata of recent CMV infection were recorded by any technique. By multivariate analysis, the only factor associated with CMV DNA in inflammatory tissue was the resistance to steroids or to three lines of treatment (risk ratio: 4.7; 95% confidence interval: 1.2-22.5). A CMV DNA load above 250 copies/mg in tissue was predictive of resistance to three successive regimens (likelihood ratio+=4.33; area under the receiver-operating characteristic curve=0.85). Eight UC patients with CMV DNA in inflamed tissue and therapeutic failure received ganciclovir; a clinical remission was observed in seven cases, with a sustained response in five of them.

CONCLUSIONS

The CMV DNA load determined in inflamed intestinal tissue predicts resistance to steroid treatment and to three drug regimens in UC. Initiation of an early antiviral treatment in these patients might delay the occurrence of resistance to current treatments.

Impact of azathioprine and tumour necrosis factor antagonists on the need for surgery in newly diagnosed Crohn's disease

OBJECTIVE

The aim of the study was to assess whether azathioprine and antitumour necrosis factor (TNF) treatment decrease the long-term need for surgery in patients with Crohn's disease.

METHODS

This was an observational study of a referral centre cohort. The cumulative incidence of the first Crohn's disease-related major abdominal surgery was estimated using the Kaplan-Meier method, and independent predictors of surgery were identified using Cox proportional hazards regression with propensity scores adjustment. Receiver operating characteristic (ROC) analysis was used to identify optimal cut-offs for duration of maintenance treatments. The electronic charts of 296 incident cases of Crohn's disease from Nancy University Hospital, France, diagnosed between 2000 and 2008, were reviewed through January 2010.

RESULTS

The median follow-up time per patient was 57 months. Seventy-six patients (26%) underwent at least one major abdominal surgical procedure. The cumulative probabilities of the first Crohn's disease-related major abdominal surgery were 6.5, 25.9 and 44.3 at 1, 5 and 9 years, respectively. In the ROC analysis, the duration of anti-TNF and azathioprine treatment had significant cut-off values (≤ 475 days ~16 months and ≤ 45 days ~1.5 months, respectively) with positive likelihood ratios (PLRs) of 1.52 (p < 0.0001) and 1.51 (p = 0.003) for the first Crohn's disease-related major abdominal surgery. Using multivariate Cox proportional hazards regression analysis (after propensity score adjustment), independent positive predictors of major abdominal surgery were stricturing (HR = 12.01; 95% CI 5.97 to 24.17) or penetrating (HR = 10.77; 95% CI 4.87 to 23.80) disease behaviour at diagnosis, duration of anti-TNF treatment of < 16 months (HR = 3.86; 95% CI 1.77 to 8.45) and duration of azathioprine treatment of < 1.5 months (HR = 2.00; 95% CI 1.20 to 3.34).

CONCLUSIONS

Non-complicated inflammatory disease behaviour and long-term anti-TNF treatment are associated with a lower risk for surgery whereas azathioprine only modestly lowers this risk.

The use of azathioprine in Crohn's disease during pregnancy and in the post-operative setting: a worldwide survey of experts

BACKGROUND

Although thiopurines are considered safe in humans, they are still pregnancy FDA category D drugs. Prevention of post-operative recurrence is a challenge in clinical practice in Crohn's disease. The European Crohn's and Colitis Organisation consensus states that thiopurines should be considered in high-risk patients.

AIM

To perform a worldwide survey for evaluating the extent to which gastroenterologists who are experts in the field of IBD are utilising thiopurines during pregnancy and in the post-operative setting in Crohn's disease.

METHODS

This was a Web-based cross-sectional, statement-based survey, which was conducted among experts who have published at least once in the field of thiopurines in IBD.

RESULTS

Between 20 December 2009 and 9 April 2010, 175 questionnaires were received. The median number of IBD patients per physician per year was 400 (IQR 25-75th, 188-600) and the total number of IBD patients followed by all responders was 82,379. In a pregnant woman with a history of severe Crohn's disease in clinical remission after 1 year on azathioprine, 89% of experts usually continue azathioprine until delivery and 9% of physicians never administer azathioprine during pregnancy. After ileocecal resection for Crohn's disease, 39% of physicians initiate azathioprine only in high-risk patients, 28% of practitioners prescribe azathioprine according to endoscopic evaluation, 20% of gastroenterologists systematically initiate azathioprine and 13% have a different attitude.

CONCLUSIONS

Almost 9 of 10 physicians continue azathioprine throughout pregnancy. About 7 of 10 physicians prescribe azathioprine in the post-operative setting according to the European Crohn's and Colitis Organisation recommendations, whereas one-fifth of practitioners systematically initiate azathioprine after surgery.

Adherence to adalimumab therapy in Crohn's disease: a French multicenter experience

BACKGROUND

We evaluated adherence to adalimumab therapy in Crohn's disease (CD).

METHODS

This was an observational multicenter study conducted in four French university hospitals between April 4, 2008 and January 1, 2010. Patients were systematically asked, at each clinical visit, whether or not they delayed or missed an injection of adalimumab over the past 3 months. Patients were also asked about the reasons for their nonadherence.

RESULTS

Of the 108 patients analyzed, 33 (30.6%) delayed the administration of at least one injection and 16 (14.8%) missed at least one injection over the past 3 months. The main reasons for overall nonadherence were: forgetfulness (24.6%), infection (24.6%), and travel (20%). Other reasons for nonadherence were intentional nonadherence (10.8%), pharmaceutical supply issues (9.2%), side effects (7.7%), pregnancy (1.5%), and CD-related hospitalization (1.5%). Adalimumab regimen of 40 mg every other week was a positive predictor for injection delays (P = 0.02, odds ratio [OR] = 3.76, 95% confidence interval [CI], 1.28-11.05), whereas having at least one relapse in the past 12 months was associated with fewer delays (P = 0.02, OR = 0.37, 95% CI, 0.15-0.87). [correction made here after initial online publication]. Disease duration over 90 months negatively predicted failure to inject adalimumab (P = 0.009, OR = 0.17, 95% CI, 0.05-0.64).

CONCLUSIONS

The overall nonadherence rate for adalimumab use was 45.4%. Most of the reasons for nonadherent behaviors could be avoided. An adalimumab regimen of 40 mg every other week was negatively related to adalimumab adherence; both the occurrence of at least one relapse in the past 12 months and disease duration over 90 months were positively related to adherence.

A multicenter experience with infliximab for ulcerative colitis: outcomes and predictors of response, optimization, colectomy, and hospitalization

OBJECTIVES

The objective of this study was to evaluate short- and long-term outcomes of infliximab in ulcerative colitis (UC), including infliximab optimization, colectomy, and hospitalization.

METHODS

This was a retrospective multicenter study. All adult patients who received at least one infliximab infusion for UC were included. Cumulative probabilities of event-free survival were estimated by the Kaplan-Meier method. Independent predictors were identified using binary logistic regression or Cox proportional-hazards regression, and results were expressed as odds ratios or hazard ratios (HRs), respectively.

RESULTS

Between January 2000 and August 2009, 191 UC patients received infliximab therapy. Median follow-up per patient was 18 months (interquartile range=25-75th, 8-32 months). Primary non-response was noted in 42 patients (22.0%). "Hemoglobin at infliximab initiation ≤ 9.4 g/dl" (odds ratio=4.35; 95% confidence interval (CI)=1.81-10.42) was a positive predictor of non-response to infliximab. Infliximab optimization was required in 36 (45.0%) of 80 patients on scheduled infliximab therapy. The only predictor of infliximab optimization was "infliximab indication for acute severe colitis" (HR=2.75; 95% CI=1.23-6.12). Thirty-six patients (18.8%) underwent colectomy. Predictors of colectomy were: "no clinical response after infliximab induction" (HR=7.06; 95% CI=3.36-14.83), "C-reactive protein at infliximab initiation > 10 mg/l" (HR=5.11; 95% CI=1.77-14.76), "infliximab indication for acute severe colitis" (HR=3.40; 95% CI=1.48-7.81), and "previous treatment with cyclosporine" (HR=2.53; 95% CI=1.22-5.28). Sixty-nine patients (36.1%) were hospitalized at least one time and UC-related hospitalizations rate was 29 per 100 patient-years (95% CI=24-35 per 100 patient-years). Predictors of first hospitalization were: "no clinical response after infliximab induction" (HR=3.87; 95% CI=2.29-6.53), "infliximab indication for acute severe colitis" (HR=3.13, 95% CI=1.65-5.94), "disease duration at infliximab initiation ≤50 months" (HR=2.14, 95% CI=1.25-3.66), "hemoglobin at infliximab initiation ≤11.8 g/dl" (HR=1.77; 95% CI=1.03-3.04), and "previous treatment with methotrexate" (HR=0.30; 95% CI=0.09-0.97).

CONCLUSIONS

Primary non-response to infliximab was noted in one fifth of patients and increased by seven and four the risks of colectomy and hospitalization, respectively. Infliximab optimization, colectomy, and hospitalization were required in half, one fifth, and one third of patients, respectively. Infliximab indication for acute severe colitis increased by three the risks of infliximab optimization, colectomy, and UC-related hospitalization.

Additional benefit of procalcitonin to C-reactive protein to assess disease activity and severity in Crohn's disease

BACKGROUND

Serum procalcitonin level may reflect non-infectious inflammation.

AIM

To assess the correlation of serum procalcitonin level with clinical, biological, endoscopic and radiological markers of disease activity in inflammatory bowel diseases (IBD), and to evaluate the additional diagnostic benefit of measuring serum procalcitonin level to that of C-reactive protein (CRP) for disease activity appraisal.

METHODS

We performed a prospective observational study. Spearman's rank correlation and receiver operating characteristic analysis were used to evaluate correlation and diagnostic accuracy respectively.

RESULTS

In Crohn's disease (CD) (n = 30), serum procalcitonin level was strongly correlated with clinical, biological, endoscopic and radiological disease activity markers. In CD, the serum procalcitonin level >0.14 μg/L demonstrated a high accuracy for detecting severe disease (Sensitivity = 100%; Specificity = 96%; AUROC = 0.963; P = 0.0001). The diagnostic accuracy of the 'serum procalcitonin level-CRP strategy' (CRP >5 mg/L and serum procalcitonin level >0.05 μg/L) was significantly superior to that of CRP alone for diagnosing severe CD (AUROC = 0.783 vs. 0.674; P = 0.01). In ulcerative colitis (UC) (n = 27), serum procalcitonin level was correlated with CRP and with endoscopic and radiological disease activity markers.

CONCLUSIONS

In CD, the serum procalcitonin level was correlated with all disease activity markers and a cut-off of 0.14 μg/L could distinguish severe forms of the disease. The 'serum procalcitonin level-CRP strategy' was superior to CRP alone for diagnosing active or severe CD.

Diffusion-weighted magnetic resonance without bowel preparation for detecting colonic inflammation in inflammatory bowel disease

OBJECTIVE

Magnetic resonance imaging (MRI) enables accurate assessment of inflammatory bowel diseases (IBD), but its main limitation is the need for bowel preparation. Diffusion-weighted imaging is feasible in Crohn's disease. We evaluated the accuracy of MRI in combination with diffusion-weighted imaging (DWI-MRI) without oral or rectal preparation in assessing colonic inflammation in both ulcerative colitis and Crohn's disease.

DESIGN

This was an observational study of a single-centre cohort.

PATIENTS

All patients who underwent DWI-MRI-colonography without bowel preparation between January 2008 and February 2010 in our centre were analysed.

RESULTS

Among the 96 patients (ulcerative colitis=35; Crohn's disease=61) who had DWI-MRI-colonography, 68 had concomitant endoscopy. In ulcerative colitis a segmental magnetic resonance score (MR-score-S) >1 detected endoscopic inflammation with a sensitivity and specificity of 89.47% and 86.67%, respectively (AUROC=0.920, p=0.0001). In the Crohn's disease group, a MR-score-S >2 detected endoscopic inflammation in the colon with a sensitivity and specificity of 58.33% and 84.48%, respectively (AUROC=0.779, p=0.0001). The MR-score-S demonstrated better accuracy for the detection of endoscopic inflammation in the ulcerative colitis group than in the Crohn's disease group (p=0.003). In ulcerative colitis, the proposed total magnetic resonance score (MR-score-T) correlated with the total modified Baron score (r=0.813, p=0.0001) and the Walmsley index (r=0.678, p<0.0001). In Crohn's disease, the MR-score-T correlated with the simplified endoscopic activity score for Crohn's disease (r=0.539, p=0.001) and the Crohn's disease activity index (r=0.367, p=0.004). The DWI hyperintensity was a predictor of colonic endoscopic inflammation in ulcerative colitis (OR=13.26, 95% CI 3.6 to 48.93; AUROC=0.854, p=0.0001) and Crohn's disease (OR=2.67, 95% CI 1.25 to 5.72; AUROC=0.702, p=0.0001). The accuracy of the DWI hyperintensity for detecting colonic inflammation was greater in ulcerative colitis than in Crohn's disease (p=0.004).

CONCLUSIONS

DWI-MRI-colonography without bowel preparation is a reliable tool for detecting colonic inflammation in ulcerative colitis.

Efficacy of TNF antagonists beyond one year in adult and pediatric inflammatory bowel diseases: a systematic review

The introduction in the mid-1990s of tumor necrosis factor (TNF) antagonists changed the treatment of inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis (UC) refractory to conventional medications (corticosteroids, immunomodulators). This review summarizes current data on the long-term efficacy and safety of anti-TNF therapy in IBD beyond 1 year. We searched Medline, the Cochrane Library, Embase, and Ovid Medliner for relevant studies. Infliximab, adalimumab and certolizumab are effective in maintaining clinical remission in luminal Crohn's disease. Infliximab and adalimumab are also effective in maintaining long-term fistula closure in Crohn's disease. Only infliximab has been evaluated in UC in the long term, with similar data on its effectiveness than in CD. In addition to the maintenance of clinical remission, TNF antagonists have the ability to maintain long-term mucosal healing, resulting in a reduced risk of surgery. With 2010 on the horizon, we have no good reasons to stop anti-TNF therapy in IBD patients because of its efficacy in maintaining remission and a risk-benefit ratio that remains in its favor. It is now clear that patients in deep remission, comprising clinical, biological, and endoscopic remission, are at lower risk of relapse after withdrawal of anti-TNF therapy.

Prevalence of hepatitis B and C and risk factors for nonvaccination in inflammatory bowel disease patients in Northeast France

BACKGROUND

Data regarding the prevalence of hepatitis C (HCV) and hepatitis B (HBV) in inflammatory bowel disease (IBD) patients are conflicting.

METHODS

In all, 315 IBD (252 Crohn's disease [CD] and 63 ulcerative colitis [UC]) patients were consecutively recruited between June 2005 and May 2009.

RESULTS

The median age was 33 years (interquartile range [IQR]: 24-43) and median disease duration was 5 years (IQR: 2-11). Present and/or past HBV and HCV infection was found in 2.86% of 315 patients (CD: HBsAg 0.79%, anti-HBc 2.78%, anti-HCV 0.79%; UC: HBsAg 1.59%, anti-HBc 1.59%, anti-HCV 1.59%). Effective vaccination (anti-HBs without anti-HBc) was present in 48.9% of 315 patients. In multivariate analysis, age at diagnosis over 31 years (odds ratio [OR] 0.29; 95% confidence interval [CI] 0.15-0.58; P = 0.005), disease duration over 7 years (OR 0.43; 95% CI 0.23-0.83; P = 0.005), age at inclusion over 33 years (OR 0.44; 95% CI 0.20-0.94; P = 0.005), and CD (OR 0.29; 95% CI 0.15-0.58; P = 0.005) were associated with the lack of effective vaccination. Two HBsAg-positive patients, including 1 under curative nucleoside/nucleotide analog treatment, had received 6 and 7 infliximab infusions, and 1 HCV RNA-positive subject had been receiving corticosteroid and azathioprine therapies for 12 and 33 months, respectively. No viral reactivation occurred in these patients.

CONCLUSIONS

The prevalence of HBV and HCV infection in French IBD patients is similar to that of the general population. While the ECCO recommends an effective HBV vaccination in IBD, half of the patients were not vaccinated. The nonvaccination risk factors identified in our study may allow targeted vaccination coverage.

Inflammatory bowel disease and hepatitis B and C

The risk of viral B and C hepatitis has long been considered to be increased in patients with inflammatory bowel disease (IBD). Blood transfusion and surgery have been identified as the two main risk factors, suggesting nosocomial transmission could be involved. However, recent epidemiologic surveys have found that prevalence in IBD patients is similar to or even lower than that in the general population. Part of the explanation of these recent data may lie in the application of protective measures against viral infection (hepatitis B virus [HBV] vaccination and hepatitis C virus [HCV]-free blood transfusions). Sometimes fatal viral reactivations have been reported in patients on immunosuppressive therapy. Two periods can be distinguished: a) during therapy, a rise in viremia associated with a decrease of immune-mediated hepatic lesions; b) after cessation of therapy, an immune rebound with a destruction of virus-infected hepatocytes. For HBV, preemptive strategy consisting of an antiviral analog is efficient in chronic HBs antigen carriers. For HCV, the impact of immunosuppressive drugs on the natural history is unclear. Most studies report improved comfort although no biopsies were performed before and after immunosuppressive treatment. Physicians managing IBD patients should be aware of the need for screening and institute preventive measures against B and C hepatitis.

Tumour necrosis factor antagonists and inflammatory bowel diseases: a national practice survey

BACKGROUND

Although the use of tumour necrosis factor (TNF) antagonists is increasingly codified, several unresolved issues remain.

AIM

To conduct a French national survey on TNF antagonists use in inflammatory bowel disease (IBD).

METHODS

A postal questionnaire was sent to all French gastroenterologists among whom 450 prescribe TNF antagonists for IBD. Only anti-TNF prescribers were invited to respond.

RESULTS

A total of 333 questionnaires could be analysed, which represented a rate of survey completeness of 74%. Scheduled maintenance infliximab treatment was prescribed by 92% of gastroenterologists. In Crohn's disease in remission after 1 year of TNF antagonists, 77.4% of physicians continued treatment. In luminal Crohn's disease, 97% of hospital practitioners introduced infliximab as first-line anti-TNF therapy vs. 78% of physicians with nonhospital activity (P = 0.002); only 22.5% of gastroenterologists opted for adalimumab as first-line therapy. In Crohn's disease in remission after 6 months of azathioprine in combination with infliximab, 63.8% of practitioners discontinued azathioprine. In case of pregnancy during anti-TNF treatment, 35.1% of physicians discontinued therapy at the time of conception and did not administer anti-TNF therapy during pregnancy.

CONCLUSIONS

The attitudes of French gastroenterologists generally reflect the recommendations regarding the use of anti-TNF and concomitant immunosuppressive therapy in IBD.

Long-term outcome of non-fistulizing (ulcers, stricture) perianal Crohn's disease in patients treated with infliximab

BACKGROUND

In Crohn's disease, anal ulcers and stricture can be disabling.

AIM

To evaluate long-term outcome of non-fistulizing perianal Crohn's disease under infliximab.

METHODS

The medical records of 99 patients with non-fistulizing perianal Crohn's disease at first infliximab infusion were reviewed. Complete responses (ulcer healing or stricture regression) after induction infliximab therapy and at the maximal follow-up were assessed.

RESULTS

Ninety-four patients (94.9%) had ulcers, 22 (22.2%) had stricture and 31 (31.3%) had draining perianal fistulas at first infliximab infusion. After infliximab induction therapy, 40/94 (42.5%) patients with ulcers, 4/22 (18.2%) with stricture and 10/31 (32.2%) with fistulas had a complete response. Eight patients were lost to follow-up. After a median follow-up of 175 weeks (range, 13-459), complete response rates for ulcers, stricture and fistulas were 72.3% (68/94), 54.5% (12/22) and 54.8% (20/31) respectively. Long-term response for cavitating ulcer was positively associated with concomitant immunosuppressant use (P = 0.017) and older age (P = 0.049). Among the 12 patients with complete regression of stricture, 6 patients also had anal dilatation. Complete response was associated with perianal pain relief and disappearance of soiling. Three patients with ulcers developed an anal abscess.

CONCLUSIONS

Infliximab therapy may be effective in inducing and maintaining response for ulcers.

Adalimumab for Crohn's disease with intolerance or lost response to infliximab: a 3-year single-centre experience

BACKGROUND

Adalimumab is effective in inducing clinical remission in patients with Crohn's disease who lost response or became intolerant to infliximab.

AIM

To evaluate long-term efficacy and safety of adalimumab as a second line therapy in luminal and fistulizing Crohn's disease.

METHODS

We report our single-centre experience in 53 patients. We evaluated maintenance of clinical response defined as the absence of adverse events leading to drug withdrawal, no major abdominal surgery and no loss of clinical response in initial responders. Major abdominal surgery, steroid sparing, complete fistula closure and safety were also assessed.

RESULTS

The probability of maintaining clinical response was 77.2%, 67.8% and 50.8% at 26, 52 and 130 weeks respectively. The probability of remaining major abdominal surgery-free was 82.3% at 26, 52 and 130 weeks. Complete fistula closure occurred in six of 10 patients, and eight of 10 patients were able to taper steroid therapy. Adverse events occurred in 31 patients (58.5%) leading to adalimumab withdrawal in nine patients (17%).

CONCLUSION

Adalimumab therapy may be effective in the long term in both luminal and fistulizing Crohn's disease in infliximab-failure patients, half of patients maintaining clinical response and potentially avoiding major abdominal surgery in 80% of cases.

TNF antagonists in the treatment of inflammatory bowel disease: results of a survey of gastroenterologists in the French region of Lorraine

BACKGROUND AND OBJECTIVE

We conducted a survey of nonacademic gastroenterologists to evaluate the use of tumor necrosis factor (TNF) antagonists in inflammatory bowel disease (IBD).

METHODS

A total of 100 questionnaires were sent by mail to a representative sample of gastroenterologists practicing in the French region of Lorraine.

RESULTS

Forty-six practitioners responded to the survey, of whom 95.5% prescribed scheduled infliximab treatment. After 6 months of infliximab in combination with azathioprine, 55% then prescribed infliximab as monotherapy. A complete pretherapeutic assessment was performed by only one fourth of the gastroenterologists. When the PPD skin test measured 7 mm, nearly half of the physicians introduced anti-TNF therapy without chemoprophylaxis (versus only 2.4% when the diameter was 11 mm). In the event of quiescent Crohn's disease (CD) after 1 year of anti-TNF treatment, 35.7% stopped the drug. In refractory CD, 72.7% prescribed infliximab as the first-line therapy (versus 27.3% who used adalimumab). In patients with urinary tract infection, 44.2% initiated antibiotics and delayed anti-TNF treatment, while 46.5% initiated anti-TNF therapy along with antibiotic therapy.

CONCLUSION

This study is the first survey upon the use of TNF antagonists by nonacademic gastroenterologists, and the findings suggest that physicians using these drugs may require more information about the pretherapeutic assessment and management of the infectious risk.

Long-term outcome of adalimumab therapy for ulcerative colitis with intolerance or lost response to infliximab: a single-centre experience

BACKGROUND

Adalimumab may be effective in inducing remission in patients with mild-to-moderate ulcerative colitis who had secondary failure to infliximab.

AIM

To evaluate long-term efficacy and safety of adalimumab in patients with ulcerative colitis who previously responded to infliximab, and then lost response or became intolerant.

METHODS

We report our single-centre experience in 13 patients. The patients received a loading dose of 160 mg of adalimumab subcutaneously in week 0, followed by 80 mg at week 2 and then 40 mg every other week starting at week 4. The primary efficacy measure was the proportion of patients on adalimumab therapy during the study.

RESULTS

Median duration of follow-up was 42 weeks (range, 10-100). The mean number of adalimumab infusions was 21 (range, 5-50). The probability of maintaining adalimumab was 92.3%, 84.6%, 60.6% and 32.5% at 1, 3, 6 and 23 months respectively. Six of 13 patients (46.2%) underwent colectomy during the study. No serious toxicities occurred in the study.

CONCLUSION

Adalimumab is well-tolerated and may be effective in maintaining clinical remission in a subgroup of patients with ulcerative colitis and lost response or intolerance to infliximab, potentially avoiding colectomy in about half of the patients.

Interaction of ribavirin with azathioprine metabolism potentially induces myelosuppression

BACKGROUND

The interaction of ribavirin, an inosine monophosphate dehydrogenase inhibitor, with azathioprine metabolism, potentially leading to myelotoxicity, remains unexplored.

AIM

To underline the interaction of ribavirin, an inosine monophosphate dehydrogenase inhibitor, with azathioprine metabolism, potentially leading to myelotoxicity.

METHODS

The medical records of eight patients who developed severe pancytopenia following concomitant use of azathioprine and ribavirin were retrospectively reviewed.

RESULTS

Bone marrow suppression reached nadir after a mean interval of 4.6 +/- 1.6 weeks following HCV therapy initiation in seven patients. At the time of pancytopenia, the mean platelet count was 69.75 +/- 82.8 x 10(-3)/mm(3), mean haemoglobin level 7.75 +/- 1.3 g/dL and mean neutrophil count 0.45 +/- 0.26 x 10(-3)/mm(3). All patients had normal thiopurine methyltransferase genotype. In two patients, a prospective monitoring of azathioprine metabolites was available. Myelotoxicity was accompanied by elevated total methylated metabolite levels (16,500 and 15,000 pmol/8 x 10(8) erythrocytes) with a concomitant decrease in 6-tioguanine nucleotide levels; 1 month after azathioprine, pegylated interferon alfa and ribavirin were discontinued and full blood count returned to normal in both patients. No haematological toxicity occurred after the reintroduction of peginterferon plus ribarivin or azathioprine alone in eight patients.

CONCLUSION

Collectively, the benefit/risk ratio favours avoidance of inosine monophosphate dehydrogenase inhibitors in purine analogue-treated patients with normal thiopurine methyltransferase activity, a situation frequently encountered in clinical practice.

[Digestive obstruction: an unusual complication of hereditary multiple exostoses]

Hereditary multiple exostoses is an autosomal dominant bone disorder characterized by multiple cartilaginous tumors growing outward from metaphyses of long bones. These tumors are usually located in long bones of the limbs. Exostosis also called osteochondroma can cause many complications, the most serious being malignant transformation as chondrosarcoma. We report a rare phenotype of this disease in a young male patient who presents digestive symptoms caused by a voluminous degenerated lumbar exostosis with anterior abdominal development.