Bleeding from the GIT can be of the following types:
In addition, when describing these, the terms ‘upper gastrointestinal bleeding’ and ‘lower gastrointestinal bleeding’ are often encountered. If the cause of bleeding is located above the ligament of Treitz (this is where the duodenum ends and the jejunum starts, the ligament of Treitz extending from the upper end of the ascending part or fourth part of the duodenum to the connective tissue around the celiac artery). The exact manifestation depends on two factors: the location and the extent of the bleed. Acute, severe bleeding from the upper gastrointestinal tract or slow bleeding from anal haemorrhoids can both present as bright red blood in the stools. Therefore saying that upper GI bleeds present with melaena is not a useful generalization, the basics need to be kept in mind when diagnosing the cause of a GI bleed.
Points to remember:
Upper GI bleeds commonly present with haematemesis. Another uncommon but serious presentation is with hematochezia (exit of fresh red blood through the anus) when the patient is bleeding too much and the blood is quickly passing through the GIT to escape through the anus.
Lower GI bleeds usually present with hematochezia.
- Overview of GI bleeding (merckmanuals.com)
- Diagnostic yield of colonoscopy for melena after nondiagnostic upper endoscopy is lower than previously reported (eurekalert.org)
- Alarm Symptoms of the Gastrointestinal Tract (theclinicaljournal.wordpress.com)