Table 1.

Clinical terminology and glossary of clinical signs in gastrointestinal bleeding.

Clinical Terminology by Type of Gastrointestinal Bleeding
UGIB	Upper gastrointestinal haemorrhage—proximal to the Treitz ligament (oesophagus, stomach and duodenum).
LGIB	Lower GI haemorrhage—distal to the Treitz ligament (colon and rectum).
SBB/MGIB	Middle gastrointestinal haemorrhage—distal to the ampulla of Vater and proximal to the ileocaecal valve (small intestine).
Suspected SBB	Gastrointestinal haemorrhage in which no source of bleeding is identified after performing both upper and lower endoscopy.
Obscure GIB	Gastrointestinal haemorrhage in which no source of bleeding is identified after the entire gastrointestinal tract has been fully evaluated with both endoscopic and advanced imaging techniques. Obscure gastrointestinal bleeding can be overt or occult depending on whether evident gastrointestinal bleeding is clinically present.
Overt GIB	Visible gastrointestinal bleeding such as haematemesis, haematochezia or melaena. The definition of overt haemorrhage is preferable to that of acute haemorrhage because the latter only defines the onset of symptoms and not the visibility of the bleeding itself. In addition, patients with overt GIB may present acutely, but also intermittently or for a prolonged period.
Occult GIB	Gastrointestinal bleeding that is not clinically visible. Patients with occult gastrointestinal bleeding have a positive faecal occult blood test or iron deficiency anaemia with no apparent cause.
Massive GIB	Gastrointestinal bleeding associated with hemodynamic instability (e.g., hypotension with systolic blood pressure <90 mmHg, tachycardia, symptoms of pre-shock or shock) or bleeding that requires transfusion of more than 4 units of packed red blood cells in 24 h.
Haematemesis	This term refers to the vomiting of blood and is indicative of bleeding from the oesophagus, stomach or duodenum. Haematemesis includes the vomiting of bright red blood, which suggests recent or current blood loss, and vomiting of coffee-like material (coffee grounds vomiting) which suggests the bleeding stopped some time ago.
Melaena	It consists of black liquid stools resulting from the breakdown of blood into haematin or other haemoglobin components by intestinal bacteria. Melaena is the manifestation of bleeding that originates from the upper GI tract, the small intestine, or the proximal portion of the large intestine. It generally occurs when 50 to 100 mL or more of blood (usually from the upper GI tract) is present in the alimentary canal, with characteristic stool passed a few hours after the bleeding event.
Haematochezia	It consists of bright red blood evacuated from the rectum and suggests active bleeding from the proximal GI tract, small intestine, distal colon or anorectal area.
Rectorrhagia	It consists of severe bleeding from the distal GI tract.