Small Bowel Infectious and Inflammatory Disease 35

Patients with disease of the small bowel can be symptomatic or asymptomatic. Symptoms can be nonspecific and overlap with those arising from other organs, such as the colon, pancreas, and liver. The small bowel is also difficult to assess clinically, being relatively inaccessible to physical and endoscopic examination. Radiological evaluation of the small bowel is, therefore, of great utility. Historically, this area has mainly been examined by means of barium fluoroscopy. However, over the last 10–15 years, with the advent of multislice computed tomography (CT) and improvements in magnetic resonance imaging (MRI) technology, such as breath-hold sequences, new cross-sectional techniques have evolved to examine this area. The technical performances of MR and CT enteroclysis and enterography are discussed in separate chapters of this book, but a brief summary of the various radiologicalmeans of investigating the small bowel will be provided. In Europe and North America, the commonest clinical scenario requiring imaging of the small bowel is the confirmation, exclusion, or staging of Crohn’s disease, and infections are rare. In other parts of the world, infestations and infections of the small bowel are more common. This chapter will deal in some detail with Crohn’s disease. More unusual inflammations of the small bowel, infections and infestations, plus the differential diagnosis of terminal ileitis will be included. The specific clinical scenario of the immunocompromised patient will be covered. Patient Management