Inflammatory bowel disease - i.e. ulcerative colitis and Crohn's disease - not only creates significant patient morbidity but also imposes a diagnostic and therapeutic challenge to the physician in charge of these patients. Since the development of sulphasalazine by Dr Nanna Svartz in Sweden half a century ago, important improvements in the prognosis of ulcerative colitis and Crohn's disease have been achieved. This book makes an attempt to present and discuss some of the most recent advances in diagnostic procedures and therapeutic approaches to inflammatory bowel disease with special respect to Crohn's disease. Although the fmal diagnosis of ulcerative colitis and Crohn's disease is generally based on endoscopic, histological or X-ray examinations, nuclear medicine and its imaging procedures have established their place in certain aspects of inflammatory bowel disease. One chapter of this book is dedicated accordingly to the indications of nuclear diagnostic procedures in the clinical setting. Sulphasalazine has been the mainstay of medical therapy in ulcerative colitis and Crohn's disease of the colon. Recently 5-aminosalicylic acid has been discovered to be its active compound and sulphapyridine was found to be the component responsible for most of the adverse effects of sulpha­ salazine. It is not surprising that many studies have investigated 5-amino­ salicylic acid as a single therapeutic agent in inflammatory bowel disease.