Infectious disorders of the upper gastrointestinal tract (excluding Helicobacter pylori )

The upper gastrointestinal (GI) tract, including the oesophagus, stomach and small intestine, harbours a wide variety of pathogens. Some infections are part of disseminated disease, whereas others produce clinicopathological scenarios that are specific to the upper GI tract. This review focuses on infectious disorders of the upper GI tract that may be encountered by the general surgical pathologist, including viral, bacterial, fungal and parasitic organisms. Diagnostic histological features are discussed, as well as useful ancillary diagnostic techniques and clinical presentation.