Article

Clinical and molecular characteristics of isolated colonic Crohn's disease.

Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK.
Inflammatory Bowel Diseases (Impact Factor: 5.48). 01/2008; 14(12):1667-77. DOI: 10.1002/ibd.20517
Source: PubMed

ABSTRACT Clinical, serological, and molecular data support the existence of discrete subsets of Crohn's disease (CD) defined by location of disease. Little is known about the epidemiology and natural history of isolated CD of the colon (Montreal Classification L2) because most studies have not accurately distinguished it from ileocolonic disease. Our objectives were to describe the clinical features and natural history of isolated colonic CD in a rigorously characterized patient cohort and to investigate the association of polymorphisms in a number of genes with colonic location of disease and disease behavior.
Patients with L2 disease were identified from a database of 675 CD patients. Only patients with a normal small bowel enema (70%), ileoscopy alone (30%), or both (20%) were included. Genotyping was performed using PCR-SSP or the iPLEX platform.
In all, 135 patients were classified with L2 disease. L2 disease was more common in women (74.0% versus 58.0%; P = 0.0004; odds ratio [OR] = 2.11, 95% confidence interval [CI] 1.36-3.26) and in never smokers (48.9% versus 36.9%; P = 0.008; OR = 1.64, 95% CI 1.09-2.45); 20.7% underwent colonic resection for severe disease. We confirmed that carriage of the HLA-DRB1*0103 allele is strongly associated with isolated colonic CD (14.9% versus 4.0%; P = 0.000016; OR 4.6, 95% CI 2.25-9.47) and report the novel association of this allele with time to first surgical event (log rank P = 0.001). There was no association with any of the known CD susceptibility loci (NOD2, IBD5, NOD1, IL23R, ATG16L1) and isolated colonic CD. A nonsynonymous polymorphism in MEKK1 (rs832582) was associated with CD susceptibility overall (15% versus 19%; P = 0.0083; OR = 1.28, 95% CI 1.07-1.54). The association was strongest in those patients not carrying a NOD2 mutation and had no effect on disease location.
This study describes the clinical features of isolated colonic CD and demonstrates the importance of the HLA region in determining the molecular basis of colonic inflammation.

Download full-text

Full-text

Available from: J R Fraser Cummings, Sep 29, 2014
0 Followers
 · 
160 Views
  • Source
    Journal of Crohn s and Colitis 03/2008; 2(1):63-92. DOI:10.1016/j.crohns.2007.12.001 · 3.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: One decade after the emergence of biologic therapy for Crohn's disease (CD), our treatment algorithms are beginning to change. Once reserved for patients with refractory disease, disease unresponsive to conventional therapies, or those requiring multiple courses of corticosteroids, there is increasing evidence that early, aggressive interventions with immunosuppressants or biologic therapies targeting tumor necrosis factor-alpha or alpha-4 integrins can alter the natural history of CD by reducing the transmural complications of structuring and fistulization and the nearly inevitable requisite for surgical resections. More recent trials are beginning to suggest that intervention with combination therapy for selected patients with a poor prognosis may modify the long-term course of CD. Selection of patients with features predicting a complex or progressive course and early, combined intervention is now possible. Future studies are still needed to best identify predictors of response to individual agents with differing mechanisms of action, as well as to optimize the risk-benefit of long-term maintenance therapy.
    Inflammatory Bowel Diseases 01/2009; 15(10):1570-82. DOI:10.1002/ibd.20918 · 5.48 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Twin studies and large-scale population studies have confirmed an increased sibling risk for both Crohn's disease (CD) and ulcerative colitis (UC). Unlike single gene disorders, CD and UC are thought to result from a complex interplay of multiple genes and environmental factors. The confirmation of CARD15/NOD2 as a CD susceptibility gene in the late 1990s caused much excitement in the field of complex diseases in general and since then, the rapid rate of progress in molecular genetics, with the advent of large-scale affordable genotyping techniques, has resulted in large collaborations and the identification of over 30 inflammatory bowel disease (IBD)-associated genes. In particular, the importance of the innate immune system has been reaffirmed with the identification of IRGM and ATG16L1 genes in the autophagy pathway as CD susceptibility genes. Disturbance in the adaptive immune system, in particular the IL-23/Th17 axis, has also shown to be of importance for IBD overall. In this era of genome-wide association studies it may be possible to, at last, identify the multiple genes involved in IBD and thus improve our understanding of the genotype-phenotype correlation and improve treatment.
    Digestive Diseases 01/2009; 27(4):428-42. DOI:10.1159/000234909 · 1.83 Impact Factor
Show more