When cases of Crohn's disease are described as "fistulizing," distinctions are often not drawn between perianal and intestinal fistulization.
The question, therefore, remains open as to whether or not there is truly an association between perianal fistulization and intraabdominal intestinal fistulization in Crohn's disease.
Dr David Sachar and colleagues have sought to determine the association between perianal and intestinal fistulization.
|The relative risk of fistulization in Crohn's was 3|
|American Journal of Gastroenterology|
The researchers analyzed the cases of Crohn's disease recorded in databases from 6 international centers.
The team searched 6 databases, which provided information on 5491 cases of Crohn's disease in the United States, France, Italy, and The Netherlands.
Of these cases, 1686 had isolated ileal disease and 1655 had Crohn's colitis.
The researchers sought an association between perianal disease and internal fistulae by calculating relative risks for the chance of internal fistulae.
The researchers compared data on patients with perianal fistulae relative to those without.
Statistical significance was calculated by the Mantel-Haenszel procedure, stratifying on the separate centers.
The research team implemented all statistical tests and estimates using SAS.
Among the 1686 cases with isolated ileal disease, the evidence of an association between perianal disease and internal fistulization was not consistent across centers.
The researchers observed that the relative risks ranged from 0.8 to 2.
For the 1655 patients with Crohn's colitis, the association was much stronger and more consistent, with an estimated common relative risk of 3.
Dr Sachar's team concludes, “We have found a statistically significant association between perianal Crohns's disease and intestinal fistulization, much stronger and more consistent in cases of Crohn's colitis than in cases limited to the small bowel.”