Gastrointestinal bleeding

Gastrointestinal haemorrhage may be from the upper gastrointestinal (UGI) or the lower gastrointestinal (LGI) tract, the demarcation being at the ligament of Treitz (a fibromuscular band that suspends the distal duodenum at the duodenojejunal junction). UGI bleeding presents with haematemesis and melaena, whereas LGI bleeding presents with frank, red blood PR (per rectum).