Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

L'objectif de cette thèse était de développer de nouveaux « donneurs de NO » stables en liant du S-nitrosoglutathion (GSNO) à une structure polymérique. Dans une première étape, les polymères ont été liés au glutathion (GSH) : le chitosan-GSH et l'alginate-GSH ont ainsi été préparés par la « méthode des carbodiimides » et dans une deuxième étape, les polymères finaux [SNOC (S-nitrosoglutathione-oligosaccharide-chitosan) et SNA (S-nitrosoglutathione-alginate)] ont été préparés par nitrosation des deux conjugués précédent. La quantité de NO fixée a été déterminée par les méthodes Griess et Saville. L’aptitude des polymères à libérer du NO et à passer la barrière intestinale [SNOC et SNA] a été évaluée dans une chambre d’Ussing. Nous avons obtenu des polymères avec des quantités variables de NO en fonction de la méthode utilisée (159 µmol de NO/g à 525 µmol de NO/g pour le SNOC ; 174 µmol de NO/g à 468 µmol de NO/g pour le SNA). Le SNOC était stable pendant au moins 6h et le SNA pendant au moins 10h. Enfin, nous avons essayé de mettre au point des microparticules de GSH et GSNO par spray drying avec de l’Eudragit ® FS 30D gastro-résistant. La caractérisation des microparticules a été réalisée par microscopie électronique à balayage (SEM), par diffraction X (PXRD) et par spectroscopie infrarouge (FTIR). Les essais de libération in vitro ont été réalisés dans un tampon (pH 1,2, 3, 6, 6,8 et 7,4). Les microparticules étaient chargées négativement avec une taille moyenne allant de 5 à 7 µm. La formulation était stable à pH acide mais a montré une libération rapide à pH basique ; elle pourrait donc servir de système de délivrance du NO au niveau intestinal. / The aim of the thesis was to develop novel and stable NO-donors by linking S-nitrosoglutathione (GSNO) to a polymer backbone. In the first step, chitosan-GSH and alginate-GSH conjugates were prepared by a carbodiimide reaction and in the second step SNOC (S-nitrosoglutathione-oligosaccharide-chitosan) and SNA (S-nitrosoglutathione-alginate) were prepared by the nitrosation of both conjugates respectively. The amount of NO was determined by Griess and Saville methods. Stability and ex vivo experiments of SNOC and SNA were performed in an Ussing chamber through rat intestine. We obtained polymers with different amount of NO (i.e. 159 µmol of NO/g to 525 µmol of NO/g for SNOC; 174 µmol of NO/g to 468 µmol of NO/g for SNA) depending upon the procedure of nitrosation. SNOC was stable for at least 6h and SNA for at least 10h. Also, we aimed to develop spray dried microparticles of GSH and GSNO based on Eudragit® FS 30D polymer. The microparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (PXRD), infrared spectroscopy (FTIR) and in vitro release studies were performed in different pH conditions (pH 1.2, 3, 6, 6.8 and 7.4). The microparticles were negatively charged with mean particle size ranging from 5 to 7 µm. The formulation was stable and was resistant to acidic pH but showed rapid release in basic pH; hence, they can be used as colon specific drug delivery systems for the treatment of Crohn’s disease. We think that these formulations could be used in animal models in the treatment of Crohn’s disease.

Introdução: Pacientes com Doença de Crohn (DC) apresentam alto risco de eventos tromboembólicos (TE), muitas vezes, associados a alta morbimortalidade. É conhecido o papel da inflamação na fisiopatologia da trombose na doença Inflamatória Intestinal (DII), entretanto, o significado da inflamação subclínica ainda se mantém obscuro na literatura. Este estudo avaliou o efeito da atividade endoscópica no perfil de coagulação dos pacientes com DC em remissão clínica. Métodos: entre os dias 22 de maio de 2015 e 26 de abril de 2017, foram triados 261 pacientes com DC em possível remissão clínica, sendo realizadas ao todo 229 colonoscopias. Das 229 colonoscopias realizadas, 164 pacientes estavam realmente em remissão clínica (confirmados com CDAI <= 150) e foram alocados em dois grupos: 75 no grupo de atividade endoscópica (AE) (SES-CD >= 7), 89 no grupo de remissão endoscópica (RE) (SES-CD <= 2). Cinquenta controles saudáveis pareados por sexo e idade foram eleitos. Medimos, nos 3 grupos, além da geração de trombina - pelo método Calibrated Automated Thrombogram (CAT), com e sem trombomodulina, - a atividade do fator tecidual (FT), fibrinogênio, D-dímero, Fator VIII, ADAMTS-13, Fator de von Willebrand - antígeno e cofator de ristocetina (cWF). Coletamos dados sobre a duração da doença, extensão, comportamento, localização, tratamento farmacológico, história prévia de cirurgias, calprotectina fecal, qualidade de vida (por meio do IBDQ), além dos fatores de risco para TE, como hospitalização recente, uso de corticoide atual, status do tabagismo, assim como marcadores de trombofilia hereditária ou adquirida. Seguimos os pacientes por 1 ano de observação, avaliando a variação no CDAI e IBDQ no período. Resultados: A maioria dos pacientes apresentou comprometimento ileocolônico (43%), com comportamento inflamatório (40%), seguido de estenosante (30%) e fistulizante (30%). 67% estavam em uso de imunossupressores e 52% em uso de biológicos. Os fatores de risco para TE e todos os outros marcadores de trombofilia, incluindo deficiência de proteína C e S, anticardiolipina, resistência à proteína C, antitrombina, mutações da protrombina e do Fator V, foram semelhantes em ambos os grupos, exceto pelo anticoagulante lúpico, maior no grupo de AE (8,1% vs. 1,3%, p=0,047). Como esperado, o grupo de AE apresentou níveis significativamente maiores de PCR, calprotectina fecal e plaquetas. Além disso, este grupo apresentou uma maior atividade do fator tecidual vs. o grupo de RE vs. controles (127 vs. 103 vs. 84, p = 0,001). Embora o grupo DC tivesse maiores níveis de FVW:Ag e FVW:RCo, FVW/ADAMTS-13, Fator VIII e trombomodulina vs. controles, não houve diferença estatística entre os grupos de AE e RE. Os níveis de geração de trombina foram semelhantes entre os 3 grupos, com ou sem trombomodulina. Conclusão: Esses dados evidenciam que existe uma disfunção endotelial inerente à DC, e, que, em pacientes com AE, essa disfunção pode ser ainda maior pela maior exposição do FT. Embora, a presença de inflamação e dano endotelial contribuam para esse estado procoagulante, em pacientes com doença subclínica, há um estado de compensação permanente, uma vez que a quantidade de trombina gerada foi a mesma entre os grupos. Este equilíbrio pode estar comprometido diante de outros fatores tromboembólicos, aumentando, assim, o risco de trombose / Background: Crohn\'s disease patients (CD) have a high risk of thromboembolic events (TE), often associated with high morbidity and mortality. Involvement of inflammation in TE is well known, but significance of the sub-clinical inflammation in this process is not the rule. Thus, the aim of this study is to evaluate the effect of the endoscopic activity in the coagulation profile in CD in clinical remission. Methods: Between May/2015 and April/2017, 261 CD patients in supposed clinical remission, were screened, and 229 had a colonoscopy done, resulting in the inclusion of 164 CD patients in clinical remission confirmed by a CDAI <= 150. They were allocated in two groups: 75 in the endoscopic activity (EA) group (SES-CD >= 7), and 89 in the endoscopic remission (ER) group (SES-CD <= 2). 50 healthy controls matched for sex and age were chosen. We measured in the 3 groups, in addition to the generation of thrombin - through the Calibrated Automated Thrombogram (CAT), with and without thrombomodulin, - the activity of tissue factor (TF), fibrinogen, D-dimer, Factor VIII, ADAMTS-13 and von Willebrand Factor - antigen (VWF) and ristocetin cofactor (VWF:RCo). We collected data regarding the duration of the disease, extension, behavior, location, pharmacological treatment, previous history of surgeries, fecal calprotectin, quality of life (through IBDQ), as well as risk factors for TE such as recent hospitalization, current corticoid use, smoking status, as well as markers of hereditary or acquired thrombophilia. We followed the patients for 1 year of observation, evaluating the variation in CDAI and IBDQ. Results: Most of the patients had ileocolonic involvement (43%), with inflammatory behavior (40%), followed by stenosing (30%) and fistulizing (30%). 67% were in use of immunosuppressors and 52% in use of biological drugs. Risk factors for TE besides other markers of thrombophilia, including protein C and S deficiency, anticardiolipin, protein C resistance, antithrombin, prothrombin and Factor V mutations, were similar in both groups except for the lupus anticoagulant, higher in the EA group (8.1% vs. 1.3%, p = 0.047). As expected, the EA group had significantly higher levels of CRP, fecal calprotectin and platelets. In addition, this group had a higher activity of TF vs. ER group vs. controls (127 vs. 103 vs. 84, p = 0.001). Although the DC group had had higher levels of VWF and VWF:RCo, VWF/ADAMTS-13, Factor VIII and thrombomodulin vs. controls, there was no statistical difference between the EA and ER groups. Thrombin generation levels were similar between the 3 groups, with or without thrombomodulin. Conclusion: These data show that there is an inherent endothelial dysfunction in CD, moreover in patients with EA, this dysfunction may be even greater, due to the exposure of TF. Although the presence of inflammation and endothelial damage contribute to this procoagulant condition, in patients with subclinical disease, there is a permanent compensatory state, since the amount of thrombin generated was the same between the groups. This balance may be compromised by other thromboembolic factors, thus increasing the risk of thrombosis

Made available in DSpace on 2015-04-14T13:32:49Z (GMT). No. of bitstreams: 1 432333.pdf: 676720 bytes, checksum: 8a62c2e5d19c905c08550681888a157a (MD5) Previous issue date: 2011-03-21 / Objetivo: Avaliar o volume de fluxo na art?ria mesent?rica superior (VFAMS) atrav?s da ultrassonografia com Doppler puls?til em crian?as e adolescentes sadios na faixa et?ria de maior incid?ncia de doen?a de Crohn. Avaliar a concord?ncia interobservador do m?todo. Materiais e m?todos: O estudo foi aprovado pelo comit? de ?tica m?dica e foi colhido o termo de consentimento informado. Estudou-se prospectivamente o volume de fluxo da art?ria mesent?rica superior em 60 volunt?rios sadios, dividido em 2 grupos de acordo com a faixa et?ria: crian?as (5-9 anos) e adolescentes (10-17 anos). Todos foram classificados segundo o estado nutricional e press?rico. Todos os volunt?rios foram examinados por 2 radiologistas independentes com longa experi?ncia e foram realizadas tr?s medidas. Resultados: Os 60 indiv?duos tinham idade m?dia de 12,2 anos, sendo 21 entre 5 e 9 anos (35%) e 39 entre 10 e 17 anos (65%). O VAMS foi significativamente menor nas crian?as (m?dia=556 ml/min; DP=122ml/min) do que nos adolescentes (m?dia=775ml/min, DP=311 ml/min), com p<0,001. Os eutr?ficos tamb?m apresentaram o VFAMS menor do que os obesos. Os indiv?duos com sobrepeso n?o apresentaram diferen?a significativa, tanto em rela??o aos eutr?ficos quanto aos obesos. Apenas a superf?cie corporal ficou associada significativamente com o VFAMS. Dessa forma, quanto maior a superf?cie corporal, maior ser? o VFAMS. Conclus?es: O VFAMS determinado pela US com Doppler a cores ? diretamente proporcional ? superf?cie corporal

Made available in DSpace on 2015-04-14T13:34:38Z (GMT). No. of bitstreams: 1 411953.pdf: 824714 bytes, checksum: 21d2b6f6306634a68a2fd17bd7dbe9b5 (MD5) Previous issue date: 2009-03-30 / Justificativa: A doen?a inflamat?ria intestinal (DII) representada pela retocolite ulcerativa (RCU) e pela Doen?a de Crohn (DC) caracteriza-se por ser uma doen?a imunol?gica sist?mica que apresenta as principais manifesta??es ao n?vel do trato gastrointestinal. ? uma doen?a multifatorial onde fatores gen?ticos interferem na predisposi??o ao desenvolvimento dos diferentes sintomas presentes nessas patologias. Alguns genes relacionados ao sistema imune j? foram indicados como alvos potenciais no desenvolvimento da DII. A mol?cula de HLA-G ? uma delas. Apesar de apresentar distribui??o tecido espec?fica e polimorfismo limitado comparado ?s mol?culas de HLA cl?ssicas, pode ser expressa diferencialmente nos processos inflamat?rios cr?nicos, vindo a favorecer respostas do tipo Th2. Objetivo: Analisar o polimorfismo inser??o/dele??o de 14 bp no ?xon 8 da regi?o 3 UTR do gene do HLA-G com a finalidade de verificar se existe associa??o entre as variantes com a DII. Material e m?todos: Foram avaliados 96 pacientes portadores de DII pertencentes ao ambulat?rio de DII do HSL-PUCRS. Foi extra?do DNA gen?mico desses indiv?duos, analisando-se a regi?o 3 UTR referente ao polimorfismo inser??o/dele??o de 14pb no ?xon 8 do HLA-G. Delineamento: Estudo transversal. Resultados: Os 96 pacientes com DII foram subdivididos em dois grupos, aqueles com DC (n = 56) e aqueles com RCU (n = 40). Realizou-se a an?lise da freq??ncia genot?pica em tr?s grupos: os homozigotos para dele??o (- 14bp/- 14bp) chamados Hd, os homozigotos para inser??o (+ 14bp/+ 14bp) denominados Hi e os heterozigotos (- 14bp/+ 14bp) chamados Ht. O padr?o de distribui??o do gen?tipo dos tr?s subgrupos (Hd, Ht, Hi) quando comparado entre os grupos de pacientes com DC, grupo de pacientes com RCU e grupo controle foi diferente (p = 0,013). A freq??ncia de Hi foi significativamente menor nos pacientes com DC (1,8%) quando comparado ao grupo de pacientes com RCU (20,0%) e ao grupo controle (15,2%) (p = 0,014). Na compara??o isolada dos grupos para a situa??o DC vs RCU observou-se um OR = 13,8 (IC95%: 1,6 a 306,6; P < 0,01) e na situa??o DC vs Controle um OR = 9,87 (IC95%: 1,44 a 195,11; P< 0,01). J? a freq??ncia Hd, foi maior nos pacientes com DC (50,0%) quando comparado ao grupo de pacientes com RCU (30,0%) e ao grupo controle (36,0%) (p = 0,08). Conclus?o: Podemos sugerir que a ocorr?ncia do gen?tipo da inser??o (+14bp) do HLA-G que direciona o padr?o de resposta imune para um padr?o do tipo Th2 ? menor nos pacientes com DC, que apresentam um padr?o de resposta imune do tipo Th1. Portanto, O gen?tipo +14pb/+14pb de HLA-G parece estar contribuindo no processo de inflama??o DII. No entanto ? essencial o aumento do n?mero amostral para confirma??o deste achado.

Depuis les cinquante dernières années, l'incidence de la maladie de Crohn,maladie chronique inflammatoire de l'intestin (MICI) a plus que doublée. C'est une pathologie multifactorielle et idiopathique utilisant des traitements comme des anti-inflammatoires, des corticoïdes, des immunosuppresseurs et plus récemment les anti-TNF.Ils présentent des limites avec une intolérance aux principes actifs et une résistance au traitement conduisant à un échec thérapeutique. L’objectif de ce travail sera de développer une forme orale tout en minimisant le risque d’effets secondaires en améliorant la biodisponibilité. Des techniques d'encapsulation protégeant les principes actifs extraits de plantes comme le Resvératrol, le Bêta-carotène, et la Curcumine seront réalisées. Quatre types de synthèse seront respectivement utilisés : la micro-encapsulation , la nanoémulsion, et la synthèse de nanoparticules solides lipidiques (SLN), ainsi que la squalénisation.Une comparaison des effets anti-inflammatoires des traitements conventionnels versus les vecteurs synthétisés au cours de cette étude pourra permettre de conclure sur la contribution originale de ce projet. / For the last fifty years, the incidence of Crohn's disease, a chronic inflammatory bowel disease (IBD) has more than doubled. It is a multifactorial and idiopathic pathology using treatments such as anti-inflammatories, corticosteroids, immunosuppressants and more recently anti-TNFα.They have limits with intolerance to active principles and resistance to treatment leading to therapeutic failure . The goal of this work will be to develop an oral form while minimizing the risk of side effects by improving bioavailability. Encapsulation techniques protecting the active ingredients extracted from plants such as Resveratrol, Beta-carotene, and Curcumin will be performed. Four types of synthesis will be used respectively: micro-encapsulation, nanoemulsion, and the synthesis of lipid solid nanoparticles (SLN), as well as squalenization. A comparison of the anti-inflammatory effects of conventional treatments versus the vectors synthesized during this study. The study may conclude on the original contribution of this project.

INTRODUÇÃO: O comprometimento pancreático em pacientes com Doença de Crohn (DC) é objeto de poucos estudos, porém as poucas séries sobre o assunto indicam um acometimento de uma parcela significativa dos pacientes, variando de 1,2% a 58%. O ultra-som endoscópico (EUS) apresenta a vantagem de apresentar uma sensibilidade muito maior que o ultra-som abdominal e a tomografia computadorizada. Quando comparado à colangiopancreatografia retrógrada endoscópica, este possui, além de uma maior sensibilidade, um índice de complicações significativamente menor. OBJETIVOS: Avaliar a incidência de alterações pancreáticas ao ultra-som endoscópico em pacientes com Doença de Crohn, correlacionando com fatores clínicos, bioquímicos e endoscópicos. MÉTODOS: Cinqüenta e um pacientes com DC, com idade entre 18 e 60 anos (média de 38 anos), sem história prévia de doença pancreática, diabetes mellitus ou alcoolismo, foram submetidos ao exame de EUS. O grupo controle foi formado por 20 pacientes submetidos ao EUS e que não apresentavam história de doença pancreato-biliar ou de Crohn. Dados clínicos, endoscópicos e laboratoriais foram coletados para posterior correlação. Onze variáveis ecoendoscópicas foram analisadas, tanto ductais quanto parenquimatosas. Os pacientes com três ou mais alterações foram submetidos à colangiorressonância magnética (CRNM). Para análise da função pancreática, foi realizado dosagens de elastase fecal em 39 pacientes. RESULTADOS: Dos pacientes analisados, 56% pertenciam ao sexo feminino, com tempo médio de diagnóstico da enfermidade de 7 anos e índice de atividade da doença (CDAI) médio de 102. Dois pacientes, (3,9%) apresentaram quatro alterações ecoendoscópicas, três pacientes, (5,9%) possuíram três alterações, 11 pacientes, (21,5%) tiveram duas alterações e 13 pacientes, (25,5%) apresentaram apenas uma alteração ao EUS. As alterações parenquimatosas totalizaram 39 achados, contra 11 alterações ductais. Apenas três pacientes (16%) do grupo controle apresentaram uma alteração ecoendoscópica (p<0,001). Os pacientes com três ou mais alterações ao EUS realizaram a CRNM, que não mostrou alterações em nenhum dos casos. Quatro pacientes, (10%) apresentaram dosagens de elastase fecal compatíveis com insuficiência pancreática exócrina, sem apresentar correlação com a ecoendoscopia. O único fator preditivo correlacionado com o número de alterações ao EUS foi doença ileal exclusiva. CONCLUSÕES: Os pacientes com DC possuíram uma alta incidência de anormalidades na morfologia pancreática (aproximadamente 10% com três ou mais alterações no EUS). Estas alterações foram localizadas predominantemente em parênquima, o que pode justificar a falta de correlação com a CRNM / BACKGROUND: Pancreas injury usually is not mentioned as an extra-intestinal manifestation of Crohns disease, but the few available series suggest pancreatic injury in a significant proportion of these patients, ranging from 1.2% to 58% in this series. Endoscopic ultrasound (EUS) presents the advantage of having a much higher sensitivity than the abdominal ultrasound or computadorized tomography in evaluating pancreas abnormalities. Compared to the endoscopic retrograde cholangiopancreatography, EUS has at least an equal sensitivity, with a lower complication rate. AIMS: To evaluate the incidence of pancreatic alterations by means of the EUS in Crohns disease, correlating them with clinical, endoscopic and biochemical data. METHODS: Fifty one patients with Crohns disease, age between 18 and 60 years-old (mean = 38), without previous history of pancreatic disease, diabetes mellitus or alcoholism, were submitted to EUS. The control-group was formed by 20 patients submitted to EUS with no previous history of pancreatic or Crohns disease. Clinical, endoscopic and biochemical data were collected in order to determine possible predictive factors. Eleven variables were analyzed, both in pancreatic parenchyma and ducts. The patients with 3 or more alterations were submitted to magnetic resonance. Pancreatic function was determined using fecal elastase assay in 39 patients. RESULTS: Of the 51 analyzed patients, 56% were female, with mean diagnosis time of seven years (1-25) and Crohns disease Activity Index (CDAI) of 102 (20-419). Two patients (3.9%) presented 4 alterations in the EUS exam, 3 (5.9%) presented 3 alterations, 11 (21.5%) had 2 alterations and 13 (25.5%) had 1 alteration in the EUS, which were statistically significant when compared to the control-group, in whom only 16% presented 1 exam alteration (p<0.001). The parenchymal abnormalities were more common, totalizing 39 findings when compared to 11 ductal abnormalities. The patients with 3 or more alterations in the exam were submitted to magnetic resonance; however, pancreatic lesions were not detected. Four patients (10%) had low fecal elastase measurement, suggestive of exocrine pancreatic insufficiency. None of these patients had significant pancreatic alterations in EUS. The only predictive factor that correlated with the number of alterations in EUS was isolated ileal disease. CONCLUSIONS: Patients with Crohns disease had a higher incidence of pancreatic abnormalities (10% with 3 or more alterations in endoscopic ultrasound) in comparison to the control-group. These alterations were found most frequently in the pancreatic parenchyma, which might explain the lack of correlation with the magnetic resonance, which is more prone to detect duct abnormalities. The only predictive factor to these alterations on EUS was ileal disease

Background: Adherent-invasive Escherichia coli (AIEC) is a pathogen isolated from the ileum of patients with CD. IFNγ is a key mediator of immunity, which regulates inflammatory responses to microbial infections. Previously, we showed enterohemorrhagic E. coli prevents STAT1 activation. Aims: To determine; 1) whether activation of STAT1 by IFNγ was prevented following AIEC infection, and 2) define the mechanisms used. Methods: Human epithelial cells were infected with AIEC strains or other pathogenic and commensal E. coli strains. Following infection, cells were stimulated with IFNγ. Activation of STAT1, was monitored by immunoblotting. Results: AIEC strains prevented STAT1 phosphorylation in response to IFNγ. Effect required live bacteria with active protein synthesis. A bacterial product was responsible for blocking STAT1 signalling and interfered with downstream signalling cascades. Conclusion: Suppression of epithelial cell STAT1 signal transduction by AIEC strains represents a novel mechanism by which the pathogen evades host immune responses to the infection.

Background: Adherent-invasive Escherichia coli (AIEC) is a pathogen isolated from the ileum of patients with CD. IFNγ is a key mediator of immunity, which regulates inflammatory responses to microbial infections. Previously, we showed enterohemorrhagic E. coli prevents STAT1 activation. Aims: To determine; 1) whether activation of STAT1 by IFNγ was prevented following AIEC infection, and 2) define the mechanisms used. Methods: Human epithelial cells were infected with AIEC strains or other pathogenic and commensal E. coli strains. Following infection, cells were stimulated with IFNγ. Activation of STAT1, was monitored by immunoblotting. Results: AIEC strains prevented STAT1 phosphorylation in response to IFNγ. Effect required live bacteria with active protein synthesis. A bacterial product was responsible for blocking STAT1 signalling and interfered with downstream signalling cascades. Conclusion: Suppression of epithelial cell STAT1 signal transduction by AIEC strains represents a novel mechanism by which the pathogen evades host immune responses to the infection.

Les manifestations orales de la maladie de Crohn sont bien établies chez les adultes. Toutefois, aucune étude ne s’est concentrée sur les manifestations orales pathologiques chez la population infantile. En ce qui concerne la santé dentaire, très peu d’études ont évalué la prévalence de carie chez les patients atteints de la maladie de Crohn. Les objectifs de cette étude sont de décrire les manifestations orales des enfants et des adolescents atteints de la maladie de Crohn et tout lien possible avec le stade de la maladie (active ou rémission) ainsi que de déterminer s’il existe un lien entre la prévalence de carie et le score de potentiel cariogène de la diète des patients. Hypothèses • Les manifestations buccodentaires décrites chez les adultes sont présentes chez les enfants et adolescents du groupe de Ste-Justine. • Il existe différentes manifestations propres à la population infantile. • L’indice carieux des enfants atteints de la maladie de Crohn est supérieur à celui des enfants en bonne santé. • L’indice de potentiel cariogène est élevé chez les patients atteints de la maladie de Crohn • Le stade de la maladie influence la prévalence des manifestations. Méthodologie Un certificat d’éthique à la recherche fut obtenu de l’hôpital Ste-Justine. Sur 40 patients recrutés, 21 sujets (9 filles, 12 garçons) âgés de 5,1 à 17,3 ans ont participé à l’étude de type transversale. Un questionnaire médical, un examen buccal complet, l’analyse des journaux alimentaires ainsi qu’une revue des dossiers médicaux a permis d’établir la prévalence des lésions pathologiques, la prévalence de carie (indice CAO) et le score de potentiel cariogène (SPC) selon la méthode du Dre Monique Julien. Résultats Les analyses statistiques démontrent: • Aucune différence significative entre le CAO des patients atteints de la maladie et celui du groupe contrôle. • Aucune manifestation orale autre que celles présentées dans la littérature. • 57% des patients ont rapporté avoir eu des ulcères buccaux au cours de la maladie. • Les patients en phase active ne sont pas différents de ceux en rémission en ce qui concerne les manifestations orales, le CAO et le SPC. • Les enfants qui prennent du méthotrexate ont un CAO plus élevé. • Les patients qui ont plus de caries n’ont pas nécessairement une diète plus cariogène. Conclusion Selon les résultats de notre étude, nous n’avons pas observé de manifestations orales propre à la population infantile. De plus, les enfants atteints de la maladie ne semblent pas être un groupe à risque de carie dentaire. Davantage d’études sont nécessaires sur les manifestations orales de la maladie de Crohn chez la population pédiatrique. / Oral manifestations of Crohn’s disease are well documented in adults. However, no studies have investigated the oral manifestations of this condition in children and adolescents. Regarding oral health, only a few studies have evaluated the prevalence of dental caries in these patients. The objectives of this study are to describe the oral manifestations of Crohn’s disease in children and establish a link between the state of the disease (active and in remission) with the prevalence of dental caries and the cariogenicity of the diet of these children. Hypotheses • The oral manifestations described in adults are present in children and adolescents of the Ste-Justine group. • There are different oral manifestations in children. • Children with Crohn’s disease have more dental caries than children in good health. • The cariogenicity index of the diet is high in patients with Crohn’s disease • The state of the disease has an effect on the prevalence of the oral manifestations. Methodology An ethic’s certification was obtained from Ste-Justine Hospital. Of 40 recruited patients, 21 patients (9 girls, 12 boys) ranging in age from 5.1 to 17.3 years of age participated in our transversal study. A medical history, a complete oral exam, a diet analysis and a review of the medical chart gave us the opportunity to record the presence of oral manifestations, the prevalence of dental caries (DMFT) and the cariogenicity score (SPC). The DMFT of Crohn’s disease patients was compared with the DMFT of Quebec children establish in the Dr. Brodeur epidemiological study conducted in 1996. The patients were also divided into two groups according to the state of the disease (active or remission) to evaluate if it affected the prevalence of oral lesions, the DMFT and the SPC. Results The statistics show : • No significant difference between the DMFT of Crohn’s disease patients and the control group. • No oral manifestations other than those published in the adult literature. • 57% of patients reported to have ulcers at some time during the disease • The patient in the active phase is not different then those in remission ones regarding oral manifestations, DMFT and SPC. • Children taking methotrexate have a higher DMFT • Patients with a higher DMFT do not necesserarily have a higher SPC Conclusion The results of our study do not demonstrate any new oral manifestations in Crohn’s disease in children that have not already been described in adults. In addition, children with Crohn’s disease do not seem to be at high risk for dental caries. Further studies are necessary on the oral manifestations of Crohn’s disease in the pediatric population.