Use of the tumor necrosis factor-blockers for Crohn's disease

Table 26 Natural history of Crohn’s disease and ulcerative colitis %

Natural history
UC		CD1
Remission at any point in time	50	Relapse	10-30
Overall intermittent course	90	Low activity	15-20
Remission: 3-7 yr after diagnosis	25	Remission	55-65
Yearly relapse	18	Chronic active	13-20
Intermittent relapse	51	Chronic intermittent	67-73
		Remission for 10 yr	13
10 yr colectomy rate	10	Surgery by 20 yr	> 75
Change in site of UC over 25 yr		Change in behavior
LC→ C	50	NSNF → S	27
C → LC	75	NSNF → F	29

¹Course 1 year after diagnosis. C: Entire colon; LC: Left colon; S: Structuring; F: Fistulising; NSNF: Non-stricturing, non-fistulizing; UC: Ulcerative colitis; CD: Crohn's disease.