The Diagnostic Approach to Monogenic Very Early Onset Inflammatory Bowel Disease

Patients with a diverse spectrum of rare genetic disorders can present with inflammatory bowel disease (monogenic IBD). Patients with these disorders often develop symptoms during infancy or early childhood, along with endoscopic or histological features of Crohn’s disease, ulcerative colitis, or IBD unclassified. Defects in interleukin-10 signaling have a Mendelian inheritance pattern with complete penetrance of intestinal inflammation. Several genetic defects that disturb intestinal epithelial barrier function or affect innate and adaptive immune function have incomplete penetrance of the IBD-like phenotype. Several of these monogenic conditions do not respond to conventional therapy and are associated with high morbidity and mortality. Due to the broad spectrum of these extremely rare diseases, a correct diagnosis is frequently a challenge and often delayed. In many cases, these diseases cannot be categorized based on standard histological and immunologic features of IBD. Genetic analysis is required to identify the cause of the disorder and offer the patient appropriate treatment options, which include medical therapy, surgery, or allogeneic hematopoietic stem cell transplantation. In addition, diagnosis based on genetic analysis can lead to genetic counseling for family members of patients. We describe key intestinal, extraintestinal, and laboratory features of 50 genetic variants associated with IBD-like intestinal inflammation. In addition, we provide approaches for identifying patients likely to have these disorders. We also discuss classic approaches to identify these variants in patients, starting with phenotypic and functional assessments that lead to analysis of candidate genes. As a complementary approach, we discuss parallel genetic screening using next-generation sequencing followed by functional confirmation of genetic defects

An integrated clinical program and crowdsourcing strategy for genomic sequencing and Mendelian disease gene discovery.

Despite major progress in defining the genetic basis of Mendelian disorders, the molecular etiology of many cases remains unknown. Patients with these undiagnosed disorders often have complex presentations and require treatment by multiple health care specialists. Here, we describe an integrated clinical diagnostic and research program using whole-exome and whole-genome sequencing (WES/WGS) for Mendelian disease gene discovery. This program employs specific case ascertainment parameters, a WES/WGS computational analysis pipeline that is optimized for Mendelian disease gene discovery with variant callers tuned to specific inheritance modes, an interdisciplinary crowdsourcing strategy for genomic sequence analysis, matchmaking for additional cases, and integration of the findings regarding gene causality with the clinical management plan. The interdisciplinary gene discovery team includes clinical, computational, and experimental biomedical specialists who interact to identify the genetic etiology of the disease, and when so warranted, to devise improved or novel treatments for affected patients. This program effectively integrates the clinical and research missions of an academic medical center and affords both diagnostic and therapeutic options for patients suffering from genetic disease. It may therefore be germane to other academic medical institutions engaged in implementing genomic medicine programs

Role of wireless capsule endoscopy in reclassifying inflammatory bowel disease in children

Objective: To evaluate the role of wireless capsule endoscopy in identifying small bowel lesions in pediatric patients with newly diagnosed colonic inflammatory bowel disease (IBD) type unclassified (IBDU), and to assess whether capsule endoscopy findings result in altered patient management. Methods: Ten pediatric patients recently diagnosed with IBDU through standard investigations were recruited from the pediatric gastroenterology clinic at McMaster Children's Hospital to undergo capsule endoscopy using the Pillcam SBTM (Given Imaging) capsule. Findings consistent with a diagnosis of Crohn's disease required the identification of at least three ulcerations. Results: Three out of ten patients had newly identified findings on capsule endoscopy that met criteria for Crohn's disease. Three more patients had findings suspicious for Crohn's disease, but failed to meet the diagnostic criteria. Three additional patients had findings most consistent with ulcerative colitis, and one had possible gastritis with a normal intestine. Findings from capsule endoscopy allowed for changes in the medical management of three patients. In all ten cases, capsule endoscopy allowed for a better characterization of the type and extent of disease. No adverse outcomes occurred in the present cohort. Conclusion: This prospective study reveals that wireless capsule endoscopy is feasible, valuable, and non-invasive, offering the ability to potentially better characterize newl

Papel da cápsula endoscópica na reclassificação da doença inflamatória intestinal em crianças Role of wireless capsule endoscopy in reclassifying inflammatory bowel disease in children

OBJETIVO: Avaliar o papel da cápsula endoscópica na identificação de lesões no intestino delgado em pacientes pediátricos com DII inespecífica (DIII) diagnosticada recentemente e avaliar se os achados da cápsula endoscópica resultam em alterações no tratamento dos pacientes. MÉTODOS: Dez pacientes pediátricos recém-diagnosticados com DIII por meio de investigações padrão foram recrutados da clínica de gastroenterologia pediátrica no McMaster Children's Hospital, para serem submetidos a exame com a cápsula endoscópica Pillcam SB TM (Given Imaging). Achados compatíveis com o diagnóstico da doença de Crohn exigiram a identificação de pelo menos três ulcerações. RESULTADOS: De 10 pacientes, três apresentaram achados novos com a cápsula endoscópica que satisfizeram o critério para a doença de Crohn. Outros três apresentaram achados com suspeita de doença de Crohn, porém não atenderam nossos critérios de diagnóstico. Apresentaram achados mais compatíveis com colite ulcerativa outros três pacientes, e um apresentava possível gastrite com intestino normal. Os achados da cápsula endoscópica possibilitaram mudanças no tratamento médico de três pacientes. Em todos os dez casos, a cápsula endoscópica permitiu uma melhor caracterização do tipo e da extensão da doença. Não houve resultado adverso em nossa coorte. CONCLUSÃO: Este estudo prospectivo revela que a cápsula endoscópica é viável, útil e não invasiva, que oferece a possibilidade de melhor caracterização de casos de DIII pediátricos recém-diagnosticados ao identificar lesões no intestino delgado e reclassificá-las como doença de Crohn.<br>OBJECTIVE: To evaluate the role of wireless capsule endoscopy in identifying small bowel lesions in pediatric patients with newly diagnosed colonic inflammatory bowel disease (IBD) type unclassified (IBDU), and to assess whether capsule endoscopy findings result in altered patient management. METHODS: Ten pediatric patients recently diagnosed with IBDU through standard investigations were recruited from the pediatric gastroenterology clinic at McMaster Children's Hospital to undergo capsule endoscopy using the Pillcam SB TM (Given Imaging) capsule. Findings consistent with a diagnosis of Crohn's disease required the identification of at least three ulcerations. RESULTS: Three out of ten patients had newly identified findings on capsule endoscopy that met criteria for Crohn's disease. Three more patients had findings suspicious for Crohn's disease, but failed to meet the diagnostic criteria. Three additional patients had findings most consistent with ulcerative colitis, and one had possible gastritis with a normal intestine. Findings from capsule endoscopy allowed for changes in the medical management of three patients. In all ten cases, capsule endoscopy allowed for a better characterization of the type and extent of disease. No adverse outcomes occurred in the present cohort. CONCLUSIONS: This prospective study reveals that wireless capsule endoscopy is feasible, valuable, and non-invasive, offering the ability to potentially better characterize newly diagnosed pediatric IBDU cases by identifying lesions in the small bowel and reclassifying these as Crohn's disease. Further investigation is warranted

Papel da cápsula endoscópica na reclassificação da doença inflamatória intestinal em crianças

OBJETIVO: Avaliar o papel da cápsula endoscópica na identificação de lesões no intestino delgado em pacientes pediátricos com DII inespecífica (DIII) diagnosticada recentemente e avaliar se os achados da cápsula endoscópica resultam em alterações no tratamento dos pacientes. MÉTODOS: Dez pacientes pediátricos recém-diagnosticados com DIII por meio de investigações padrão foram recrutados da clínica de gastroenterologia pediátrica no McMaster Children's Hospital, para serem submetidos a exame com a cápsula endoscópica Pillcam SB TM (Given Imaging). Achados compatíveis com o diagnóstico da doença de Crohn exigiram a identificação de pelo menos três ulcerações. RESULTADOS: De 10 pacientes, três apresentaram achados novos com a cápsula endoscópica que satisfizeram o critério para a doença de Crohn. Outros três apresentaram achados com suspeita de doença de Crohn, porém não atenderam nossos critérios de diagnóstico. Apresentaram achados mais compatíveis com colite ulcerativa outros três pacientes, e um apresentava possível gastrite com intestino normal. Os achados da cápsula endoscópica possibilitaram mudanças no tratamento médico de três pacientes. Em todos os dez casos, a cápsula endoscópica permitiu uma melhor caracterização do tipo e da extensão da doença. Não houve resultado adverso em nossa coorte. CONCLUSÃO: Este estudo prospectivo revela que a cápsula endoscópica é viável, útil e não invasiva, que oferece a possibilidade de melhor caracterização de casos de DIII pediátricos recém-diagnosticados ao identificar lesões no intestino delgado e reclassificá-las como doença de Crohn