Clinical scenarios in IBD: Optimizing the use of conventional and biologic agents

Crohn's disease (CD) and ulcerative colitis (UC)—known collectively as inflammatory bowel disease (IBD)—are chronic, inflammatory disorders that can become disabling over time. CD, in particular, is a generally progressive and luminally destructive disorder: most patients with CD eventually develop enteric structural complications that require (multiple) hospitalizations and surgeries.1, 2 Prospective longitudinal data indicate that although most patients with CD present initially with inflammatory disease, ≈80% of patients develop stricturing or penetrating complications within 20 years.1 Further, approximately half of patients require surgical resection within 10 years of diagnosis, with a similar number of patients experiencing postoperative recurrence after 10 years.2 Despite the progressive course of the disease, however, the clinical course of IBD and the rate at which patients develop complications vary markedly, with about half of patients with either CD or UC in remission at any given time.3, 4 Given the variability in clinical course, the ability to predict which patients are likely to develop complicated disease—and how they might respond to conventional or biologic agents—would be invaluable in guiding therapeutic decisions. To that end, an increasing number of clinical, serologic, and biologic factors that affect patient outcome have been identified (Table 1).