Patterns of postoperative recurrence in Crohn's disease

The most difficult problem in the management of Crohn's disease is that the condition is permanent and incurable. Even though most patients ultimately have resection surgery and are thereby greatly improved, in most cases the disease recurs within several years after the operation. This phenomenon of postoperative recurrence has been recognized for decades, yet there has been little agreement concerning such important issues as the frequency, rate, and risk factors of recurrent disease. The reasons for disagreement are primarily methodologic and fall into three major categories: 1) different definitions of recurrence; 2) different operative procedures; and 3) different statistical methods. Two factors in particular seem to exert the strongest influence on the rates of postoperative recurrence. One is the surgical procedure itself, with recurrences appearing faster and more frequently after anastomoses than after ileostomies. The second and perhaps more important factor is the behavior of the underlying disease. Data suggest that an aggressive fistulizing form of Crohn's disease brings patients to surgery sooner and is followed by a faster rate of postoperative recurrence and reoperation; the disease also tends to recur with fistulous complications similar to the original ones. By contrast, a more indolent obstructing form of Crohn's disease brings patients to surgery later and is followed by a slower rate of recurrence and reoperation; this form of disease tends to recur with obstructive complications. The recognition of these two different clinical forms of Crohn's disease may have important prognostic and even pathophysiologic implications.