Rutgeerts score (1) is used as the standard evaluation of post-surgical recurrences at ileocolic anastomosis level, and should only be used for this purpose.
After curative resection for Crohn's disease, the cumulative rate of symptomatic recurrence at 3 years is approximately 50%.
Endoscopic examination has proven to be able to detect signs of endoscopic recurrence in up to 60-70% of patients at 6-12 months. It was also demonstrated that the severity of endoscopic recurrence is predictive of the following clinical outcome: if there is no recurrence or only mild endoscopic recurrence (less than five aphthous ulcers) within the first year after resection, the rate of symptomatic relapse in 7 years is 9%, while all patients with severe endoscopic recurrence had a symptomatic relapse
within 4 years (2).
Rutgeerts Score correlates with the risk of symptomatic recurrences: the risk of having symptoms of the disease within 5 years after a post-surgical control endoscopy changes from 6% of the patients classified as i0 and i1, to 27% of patients classified as i2, 63% for patients i3 and 100% for subjects i4.

Rutgeerts score decoding is as follows.

Rutgeerts grade Decoding
i0 post-surgery remission
i1 post-surgery remission
i2 substantial post-surgery recurrence
i3 advanced post-surgery recurrence
i4 advanced post-surgery recurrence

Below are summarized for each grade of the score, the endoscopic findings and the corresponding relative risk of symptomatic recurrence at 5 years. The probability of absence of symptoms is equal to 100 minus the % risk.

Endoscopic finding Risk of symptomatic
recurrence at 5 years
Probability of absence
of symptoms at 5 years
i0 No lesions in the distal ileum 6% 94%
i1 Not more than 5 anastomotic aphthous lesions in the distal ileum 6% 94%
i2 More than 5 aphthous lesions with normal mucosa between the lesions, or skip areas of larger lesions or ulcers up to 1 cm confined
to ileocolonic anastomosis
27% 73%
i3 Diffuse aphthous ileitis with diffusely inflamed mucosa
between the multiple aphthae
63% 37%
i4 Diffuse inflammation, with larger lesions: large ulcers
and/or nodules/cobble and/or narrowing/stenosis
100% 0%

There is currently no formal validation of the score, although it is widely used in almost all clinical trials on post-surgical recurrence and represents an example of how the endoscopic lesions, even in the absence of symptoms, can predict the evolution of the disease.

  • Rutgeerts P, Geboes K, Vantrappen G, Beyls J, Kerremans R, Hiele M. Predictability of the postoperative course of Crohn's disease. Gastroenterology 1990; 99 (4): 956-963.
  • Sostegni R, Daperno M, Scaglione N, et al. Review article: Crohn’s disease: monitoring disease activity. Aliment Pharmacol Ther 2003; 17: 11-17.