Genetic testing in Crohn disease: utility in individualizing patient management.

摘要: Inflammatory bowel disease (IBD), with its two subforms of Crohn and ulcerative colitis, is a polygenic that manifests due to environmental trigger factors on the background complex genetic predisposition. The first risk gene underlying susceptibility has been identified as CARD15 (located chromosome 16q12, encoding NOD2). Three single nucleotide polymorphisms in leucine rich region (LRR) this are strongly independently associated explain up 20% total predisposition for disease. These variants have consistently replicated particular sub-phenotype characterized by small (ileum) involvement early age at onset. Presently, testing only modest relevance clinical practice. most attractive use prediction response therapy. Most therapies show efficacy subgroups patients no parameters available distinguish, prior therapy, whether will be responders or non-responders, if experience adverse effects. pharmacogenetic basis toxicity well known azathioprine: several thiopurine methyltransferase (TPMT) reduced activity drug metabolizing enzyme result cytotoxic immunosuppressive effects azathioprine. Genetic screening, which found way into routine diagnostics, allows identification who not tolerate standard dose drug. extensive search predictors anti-tumor necrosis factor treatment infliximab, results remission rate 30-40%, has, however, failed identify variation differential response.