The differential diagnosis of Crohn's disease by conventional radiological examination.

The difficulties in the differential diagnosis of Crohn's disease are discussed on the basis of 35 patients observed at the Kantonsspital of Lucerne. The value of various radiographic signs as indicators of the stage and duration and the activity of the disease is critically analysed. Functional radiological signs, such as spasm, hypertonia and edema of the intestinal folds cannot be interpreted as early signs of Crohn's disease. On the other hand, advanced radiological lesions may be found although the disease is clinically acute and of recent onset. Sometimes, the radiological differential diagnosis against advanced ulcerative colitis or acute ileitis is made only on the basis of follow-up studies and the evolution of the lesions.