L’utilisation des corticostéroïdes et le retard de croissance linéaire chez les enfants atteints de la maladie de Crohn

La maladie de Crohn (MC) est une maladie chronique et récidivante du tractus gastro-intestinal. Dans la population pédiatrique, elle est très souvent accompagnée d'un retard de croissance (jusqu'à 88%). La MC se manifeste souvent autour de la puberté d’où l’importance du retard de croissance linéaire à ce stade crucial du développement de l’enfant. Une des questions essentielles est de savoir si le retard de croissance peut persister à l'âge adulte. La littérature est inconsistante sur ce point. En ce qui concerne les facteurs de risque potentiels, les corticostéroïdes (CS) qui sont la première ligne de traitement pour la majorité des patients, ont été largement impliqués. Bien qu'il existe des explications démontrant le mécanisme d’action des corticostéroïdes sur la croissance linéaire, les études cliniques impliquant l'utilisation CS soit à un retard de croissance temporaire ou permanent restent controverser et limiter. Nous avons examiné cette relation importante dans notre étude présente. Les principaux objectifs de l'étude sont les suivants: 1. D’évaluer la fréquence du retard de croissance chez le jeune atteint de la maladie de Crohn et qui a reçu des corticostéroïdes (CS) au cours de son traitement et 2. D’évaluer les facteurs de risque associés au retard de croissance temporaire ou permanent dans cette population. Méthodes : Afin d’atteindre nos objectifs, on a mené une étude de cohorte rétrospective. Cette cohorte comprend des patients qui ont été diagnostiqués de la MC (avant l’âge de 18 ans) à la clinique de gastroentérologie du Centre Hospitalier-Universitaire Sainte-Justine (CHUSJ) à Montréal. Ces patients ont tous reçus des CS en traitement initial(en excluant les rechutes). Les dossiers médicaux des patients ont été examinés de façon prospective afin de d’acquérir des informations sur : 1. La taille à chaque visite médicale; 2. La durée du traitement des CS; 3. L’administration de médication concomitante; 4. D’autres variables cliniques telles que l’âge au diagnostic, le sexe, la localisation et le comportement de la maladie. Pour ceux qui avaient atteints l’âge de 18 ans et qui ne fréquentaient plus la clinique, leur taille finale a été obtenue en les contactant par téléphone. Leurs parents ont aussi été contactés afin d’obtenir leur taille. On a converti nos résultats en scores de Z ou scores-Z ajustée pour l’âge et le sexe en utilisant la classification 2007 de l’Organisation Mondiale de la Santé(OMS). On a aussi calculé les tailles adultes cibles avec les données que nous avons récoltées. La raison de tout cela était de rendre nos résultats comparables aux études antérieures et renforcer ainsi la validité de nos trouvailles. Les enfants avec un score de Z<-1.64 (qui correspond au 5ème percentile) ont été considérés comme ayant un retard de croissance temporaire. Les scores-Z pour les tailles adultes finales ont été calculés en utilisant les mêmes normes de référence selon le sexe pour les personnes âgées de 17,9 ans. Un z-score <-1,64 a aussi été utilisé pour classer les individus avec un retard permanent. Ajouter à cela, ceux ayant une taille adulte finale <8,5cm de leur taille adulte cible (estimée à partir des hauteurs parentales) étaient considérés comme ayant un retard de croissance permanent. Des analyses de régression logistiques ont été faites pour examiner les facteurs associés à un retard de croissance temporaire et/ou permanent. Résultats : 221 patients ont été retenus. L’âge moyen de diagnostic était de 12.4 années et l’âge moyen de prise de CS était de 12.7 années. La répartition par sexe avait une légère prédominance masculine 54.3% contre 45.7% pour le sexe féminin. La majorité des patients étaient d’âge pubère (62.9%). On a surtout des patients avec une prédominance de maladie de type inflammatoire (89.1%) et localisé au niveau de l’iléo-colon (60.2%). Presque tous avaient pris une médication concomitante (88.7%) et n’avaient subi aucune chirurgie (95.9%). 19% des patients avaient un retard de croissance temporaire. L'analyse univariée a suggéré que le plus jeune âge au moment du diagnostic de la maladie et l'âge précoce à l'administration de stéroïdes étaient associés à un risque accru de retard de croissance temporaire. L’administration de CS à un jeune âge a été la seule variable (dans l’analyse multivariée) associée à un risque élevé de retard de croissance temporaire. En comparant à ceux ayant reçu des CS après l’âge de 14 ans (tertile 3), l’administration de CS à un âge précoce est fortement associé à un risque de retard de croissance (<11.6ans, OR: 6.9, 95% CI: 2.2-21.6, p-value: 0.001; 11.8ans-14ans, OR: 5.4, 95% CI: 1.7-17.1, p-value: 0.004). 8 (5.8%) sur 137 des sujets avaient une taille adulte finale <8,5cm de leur taille adulte cible. Dans l’analyse de régression linéaire multivariée, seul la variable de la taille adulte cible était associé à un changement de la taille adulte finale. Conclusion : Nos résultats suggèrent que la fréquence du retard de croissance permanent chez les enfants atteint de la MC est très faible. Un retard temporaire ou permanent de la croissance n’ont pas été associés à une augmentation de la quantité de CS administrée bien que l'administration de CS à un âge précoce soit associée à un retard de croissance temporaire.

Étude sur le rôle de SIGIRR chez les cas pédiatriques dans la maladie de Crohn.

Il est admis que la maladie de Crohn (MC) résulte de facteurs immunologiques, environnementaux et génétiques. SIGIRR, un récepteur anti-inflammatoire, n’a jamais été étudié dans le contexte de la MC, et de nombreuses découvertes à son sujet ont mené plusieurs à s’intéresser quant à son utilité dans l’atténuation de maladies inflammatoires. Récemment, l’IL-37 a été identifié comme ligand d’un complexe formé de SIGIRR-IL-18Rα. SIGIRR et l’IL-37 pourraient alors être des acteurs de la dérégulation de l’inflammation retrouvée chez la MC. Nous les avons étudiés dans le contexte de la MC pédiatrique, afin d’y caractériser leurs effets. Nous avons identifié une diminution de l’expression de SIGIRR sur certains types de cellules immunitaires. De plus, les personnes atteintes de la MC ont des concentrations de protéines altérées, soit SIGIRR soluble, l’IL-37, l’IL-18BP, et l’IL-18, et tendent à revenir à la normale lorsque l’inflammation est contrôlée par médication. De plus, la concentration de l’IL-18 libre suit le même patron. Par analyse de régression linéaire de SIGIRR soluble et l’IL-37, de l’IL-18BP et l’IL-18, ainsi que l’IL-37 et l’IL-18, des tendances divergentes ont été identifiées entre les patients non traités aux contrôles et patients traités. Nos résultats suggèrent que le système IL-37-SIGIRR est compromis chez les patients de la MC. Étant donné que ce système est un facteur crucial dans la régulation négative de l’inflammation, il sera intéressant de déterminer si SIGIRR et l’IL-37 peuvent constituer des cibles thérapeutiques importantes dans l’atténuation et la résolution de l’inflammation chez les patients atteints de la MC.

Aspectos psicopatológicos en la enfermedad de Crohn y en la colitis ulcerosa

Las enfermedades inflamatorias del intestino (EII) son trastornos crónicos que inflaman y destruyen el tejido intestinal de forma periódica y recurrente. Las EII se clasifican en dos tipos: enfermedad de Crohn (EC) y colitis ulcerosa (CU). La etiología tanto de la EC como de la CU es poco conocida y el curso está influido por múltiples factores de tipo biopsicosocial. Al respecto, diversas investigaciones están aportando evidencia de la implicación de factores psicológicos en el curso de las EII, tales como el estrés psicosocial, las estrategias de afrontamiento, las características de personalidad, los síntomas psicopatológicos y el apoyo social.

Intestinal microbiology in Crohn's disease: a study of Escherichia coli as a potential etiologic agent

La malaltia de Crohn és una malaltia inflamatòria intestinal crònica d'etiologia encara desconeguda. Actualment es pensa que hi participen factors genètics i immunològics que confereixen una susceptibilitat a l'hoste, i factors externs o ambientals, com serien els microorganismes i/o l'estil de vida. L'objectiu principal d'aquest treball ha estat descriure les poblacions bacterianes associades especialment als malalts de Crohn, amb la intenció d'identificar possibles agents etiològics. Els resultats d'aquest treball coincideixen amb investigacions prèvies que descriuen l'alteració bacteriana present en els malalts de Crohn (disbiosi) i recolzen la hipòtesi que implica el recentment descrit patovar "Adherent- Invasive Escherichia coli" (AIEC) en l'etiologia d'aquesta malaltia inflamatòria intestinal. A més, contribuïm a la descripció de les poblacions d'E. coli associades a la mucosa intestinal aportant dades sobre aspectes ecològics i patogènics. Finalment, descrivim nous aspectes fenotípics d'AIEC que podrien estar relacionats amb la seva patogènia, com seria la capacitat de formar biofilms.

Molecular inventory of faecal microflora in patients with Crohn's disease

Intestinal microbial community is involved in the pathogenesis of Crohn's disease, but knowledge of its potential abnormalities has been limited by the impossibility to grow many dominant intestinal bacteria. Using sequence analysis of randomly cloned bacterial 16S ribosomal DNA, the dominant faecal species from four Crolin's disease patients and four controls were compared. Whereas marked inter-individual differences were observed in the faecal microflora of patients, three remained distantly related to controls on the basis of their operational taxonomic unit composition. Bacteroides vidgatus and closely related organisms represented the only molecular species shared by all patients and exhibited an unusually high rate of occurrence. Escherichia coli clones were isolated only in two patients with ileocolonic Crohn's disease. Moreover, numerous clones belonged to phylogenetic groups or species that are commonly not dominant in the faecal microflora of healthy subjects: Pectinatus, Sutterella, Verritcomicrobium, Fusobacterium, Clostridium disporicum, clostridium glycolicum, Clostridium ramosum, Clostridium innocuum and Clostridium perfringens. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

Rifaximin modulates the colonic microbiota of patients with Crohn's disease: an in vitro approach using a continuous culture colonic model system.

Rifaximin, a rifamycin derivative, has been reported to induce clinical remission of active Crohn's disease (CD), a chronic inflammatory bowel disorder. In order to understand how rifaximin affects the colonic microbiota and its metabolism, an in vitro human colonic model system was used in this study. We investigated the impact of the administration of 1800 mg/day of rifaximin on the faecal microbiota of four patients affected by colonic active CD [Crohn's disease activity index (CDAI > 200)] using a continuous culture colonic model system. We studied the effect of rifaximin on the human gut microbiota using fluorescence in situ hybridization, quantitative PCR and PCR–denaturing gradient gel electrophoresis. Furthermore, we investigated the effect of the antibiotic on microbial metabolic profiles, using 1H-NMR and solid phase microextraction coupled with gas chromatography/mass spectrometry, and its potential genotoxicity and cytotoxicity, using Comet and growth curve assays. Rifaximin did not affect the overall composition of the gut microbiota, whereas it caused an increase in concentration of Bifidobacterium, Atopobium and Faecalibacterium prausnitzii. A shift in microbial metabolism was observed, as shown by increases in short-chain fatty acids, propanol, decanol, nonanone and aromatic organic compounds, and decreases in ethanol, methanol and glutamate. No genotoxicity or cytotoxicity was attributed to rifaximin, and conversely rifaximin was shown to have a chemopreventive role by protecting against hydrogen peroxide-induced DNA damage. We demonstrated that rifaximin, while not altering the overall structure of the human colonic microbiota, increased bifidobacteria and led to variation of metabolic profiles associated with potential beneficial effects on the host.

Infliximab-induced psoriasis during therapy for Crohn's disease

Although therapy with tumor necrosis factor-alpha inhibitors (anti-TNF) provides beneficial effects in different immune inflammatory disorders, paradoxical cases of anti-THE-induced psoriasis have increasingly been reported, mostly in the setting of rheumatologic diseases. To date, less than 50 cases of infliximab-induced psoriasis in inflammatory bowel disease patients have been described. The present report was aimed at describing two new cases of infliximab-induced psoriasis during therapy for Crohn's disease and at carrying out a review on this intriguing phenomenon. (C) 2011 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.

Mucosa-associated but not luminal Escherichia coli is augmented in Crohn's disease and ulcerative colitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adalimumab for maintenance therapy for one year in Crohn's disease: results of a Latin American single-center observational study

Adalimumab is a fully-human antibody that inhibits TNF alpha, with a significant efficacy for long-term maintenance of remission. Studies with this agent in Latin American Crohn's disease patients are scarce. The objective of this study was to outline clinical remission rates after 12 months of adalimumab therapy for Crohn's disease patients. Retrospective, single-center, observational study of a Brazilian case series of Crohn's disease patients under adalimumab therapy. Variables analyzed: demographic data, Montreal classification, concomitant medication, remission rates after 1, 4, 6 and 12 months. Remission was defined as Harvey-Bradshaw Index ≤ 4, and non-responder-imputation and last-observation-carried-forward analysis were used. The influence of infliximab on remission rates was analyzed by Fischer and Chi-square tests (P<0.05). Fifty patients, with median age of 35 years at therapy initiation, were included. Remission rates after 12 months of therapy were 54% under non-responder-imputation and 88% under last-observation-carried-forward analysis. After 12 months, remission on patients with previous infliximab occurred in 69.23% as compared to 94.59% in infliximab-naïve patients (P = 0.033). Adalimumab was effective in maintaining clinical remission after 12 months of therapy, with an adequate safety profile, and was also more effective in infliximab naïve patients.

Direct retrospective comparison of adalimumab and infliximab in preventing early postoperative endoscopic recurrence after ileocaecal resection for crohn's disease: results from the MULTIPER database

Both adalimumab [ADA] and infliximab [IFX] seem to be effective in the prevention of early postoperative endoscopic recurrence [EPER] after ileocaecal resection in Crohn's disease [CD] patients. There is lack of data with direct comparison between the two agents in the postoperative scenario. The aim of this study was to compare the rates of EPER in patients treated with ADA and IFX after ileocaecal resection for CD. This was a multicentre retrospective analysis of EPER rates in CD patients after ileocaecal resections, from seven referral centres in three countries. Endoscopic recurrence was defined as Rutgeerts' score ≥ i2. The patients were allocated according to treatment to two groups: ADA or IFX. The EPER rates were compared between the two treatment groups. Among the 168 patients included in the database, 96 received anti-tumour necrosis factor [TNF] agents after resection [37 in the ADA and 59 in the IFX groups] and were included in this comparative study. The groups were comparable in all baseline characteristics, mainly age, gender, previous resections, perianal CD, and mono or combination therapy. EPER was identified in 9/37 [24.32%] in the ADA group vs 16/59 [27.12%] in the IFX group [p = 0.815]. In this retrospective direct comparison between ADA and IFX therapy after ileocaecal resection, there was no significant difference between the two anti-TNF agents in terms of EPER rates. However, prospective randomised studies are needed to confirm these data and better define the role of each agent in the prevention of EPER.

Conventional versus biological therapy for prevention of postoperative endoscopic recurrence in patients with Crohn's disease: an international, multicenter, and observational study

Postoperative endoscopic recurrence (PER) occurs in nearly 80% of patients 1 year after ileocecal resection in patients with Crohn's disease (CD). Biological agents were more effective in reducing the rates of PER in comparison with conventional therapy, in prospective trials. The aim of this study was to compare the PER rates of biological versus conventional therapy after ileocecal resections in patients with CD in real-world practice. The MULTIPER (Multicenter International Postoperative Endoscopic Recurrence) database is a retrospective analysis of PER rates in CD patients after ileocecal resection, from 7 referral centers in 3 different countries. All consecutive patients who underwent ileocecal resections between 2008 and 2012 and in whom colonoscopies had been performed up to 12 months after surgery, were included. Recurrence was defined as Rutgeerts' score ≥i2. The patients were allocated to either biological or conventional therapy after surgery, and PER rates were compared between the groups. Initially, 231 patients were evaluated, and 63 were excluded. Of the 168 patients in the database, 96 received anti-tumor necrosis factor agents and 72 were treated with conventional therapy after resection. The groups were comparable regarding age, gender, and perianal disease. There was longer disease duration, more previous resections, and more open surgical procedures in patients on biologicals postoperatively. PER was identified in 25/96 (26%) patients on biological therapy and in 24/72 (33.3%) patients on conventional therapy (P=0.310). In this retrospective observational analysis from an international database, no difference was observed between biological and conventional therapy in preventing PER after ileocecal resections in CD patients.

Biological therapy for the prevention and treatment of postoperative endoscopic recurrence in Crohn's disease: time for acceptance?

In most patients, postoperative endoscopic recurrence (PER) occurs 1 year after abdominal resection for Crohn’s disease (CD). Preventing PER is essential for disease control, as most patients develop further clinical and surgical recurrences. Conventional therapy with nitroimidazoles, aminosalicylates, and immunomodulators have limited efficacy for preventing PER. Initial trials with biological therapy (infliximab and adalimumab) showed promising results in preventing PER, and the efficacy of these drugs seems higher than that with conventional therapy. The aim of this review is to outline the results of studies that used infliximab or adalimumab for preventing and treating PER in CD patients. Data with both agents are available, and a few, small prospective trials have shown the efficacy of these drugs in patients with a high risk for recurrence. We believe that, in 2013, biological agents will be better accepted for the prevention PER in CD patients, in addition to the already existing data. Larger trials are still underway, and their results will certainly determine the role of these agents in PER, which develops after bowel resection for CD.

Risk factors for postoperative endoscopic recurrence in Crohn's disease: a Brazilian observational study

Introduction: Postoperative endoscopic recurrence (PER) is the initial event after intestinal resection in Crohn’s disease (CD), and after a few years most patients present with progressive symptoms and complications related to the disease. The identification of risk factors for PER can help in the optimization of postoperative therapy and contribute to its prevention. Methods: Retrospective, longitudinal, multicenter, observational study involving patients with CD who underwent ileocolic resections. The patients were allocated into two groups according to the presence of PER and the variables of interest were analyzed to identify the associated factors for recurrence. Results: Eighty-five patients were included in the study. The mean period of the first postoperative colonoscopy was 12.8 (3–120) months and PER was observed in 28 patients (32.9%). There was no statistical difference in relation to gender, mean age, duration of CD, family history, previous intestinal resections, smoking, Montreal classification, blood transfusion, residual CD, surgical technique, postoperative complications, presence of granulomas at histology, specimen extension and use of postoperative biological therapy. The preoperative use of corticosteroids was the only variable that showed a significant difference between the groups in univariate analysis, being more common in patients with PER (42.8% vs. 21%; p = 0.044). Conclusions: PER was observed in 32.9% of the patients. The preoperative use of corticosteroids was the only risk factor associated with PER in this observational analysis.