The aim of this study was to evaluate the accuracy of enteroclysis in the diagnosis of Crohn's disease of the small bowel in a group of consecutive patients. From January 1992 to December 1995, 165 patients with suspected Crohn's disease of the small bowel presented to our institution for enteroclysis. In 14 patients up to three enteroclysis exams were performed. Most patients (78%) underwent colonoscopy and retrograde ileoscopy. In the remaining patients clinical follow-up was used as gold standard. In 79 patients no radiographic abnormalities were found. Sixty-one patients (40 men and 21 women; mean age 34.2 years) had a radiological diagnosis of Crohn's disease. This involved the terminal ileum in 39 patients (64%) either alone (n = 25) or in association with the pelvic ileum (n = 14). In 12 of these patients retrograde ileoscopy was not feasible. Twenty-one patients underwent surgery. In 4 patients pathology revealed diseases other than Crohn's. These patients had all ileocecal diseases (tuberculosis = 2; non-Hodgkin's lymphoma = 1; adenocarcinoma = 1). One false-negative result was observed. Overall, enteroclysis showed a sensitivity of 98.2% and a positive predictive value of 93.4%. Enteroclysis is a sensitive technique in evaluating both the extent and the severity of small bowel involvement in Crohn's disease, although the overlap of radiographic findings may hamper its accuracy when the disease is confined to the ileocecal area.