Enteritis and colitis are heterogeneous diseases with a multitude of potential causes, including inflammatory, infectious, and ischaemic processes. Consequently, the differential diagnosis of these conditions is inherently broad. Enteritis and colitis are classified into two main categories: infectious and inflammatory. These are, in turn, subdivided into primary (inflammatory bowel disease, vasculitis) and secondary forms (i.e. drug-induced disorders, radiation therapy enterocolitis, graft versus host disease). The management strategy for each case is substantially different, which makes appropriate radiological identification crucial, particularly in the acute setting. However, CT findings are rather non-specific; only an evaluation of the distribution of alterations with an overall assessment of all the signs present can lead to a hypothesis about the cause/etiology of the disease. Integration with clinical, laboratory, and microbiological data is always necessary to reach a diagnosis.