Melena is a form of digestive bleeding. In most cases, it is a hemorrhage (loss of blood) from the right angle of the colon.
Definition of melena
Melena is a form of hemorrhage from the digestive system. This is the evacuation of black blood through the anus.
This type of digestive hemorrhage results in the expulsion of blood from the digestive system: the digestive tract, bile ducts, or the pancreas.
However, melena is not to be confused with other digestive hemorrhages and other intestinal complications: coughing up blood, nasal bleeding, gynecological bleeding such as menstruation, etc.
In addition, high hemorrhages (whose origin is upstream of the duodenojejunal angle) are to be distinguished from low hemorrhages (whose origin is downstream of this angle). Melena is then a low hemorrhage. and comes, in a majority of cases, from hemorrhage of the right angle of the colon.
The causes of melena
Different causes can be at the origin of melena:
- the presence of a polyp (growth of intestinal mucosa) or cancer
- diverticular bleeding (caused by small hernias formed in the intestinal wall)
- ischemic, infectious, inflammatory, or radiation colitis
- rectal ulcer (especially in the elderly)
- hemorrhoidal bleeding from hemorrhoids
In rare cases, melena can find its origin as a result of angiodysplasia, tumors, and ulcerations by nonsteroidal anti-inflammatory drugs (NSAIDs).
Who is affected by melena?
People with damage to the digestive system are more at risk of melena (gastric or intestinal ulcer, ischemic colitis, etc.).
Older people are also at higher risk of melena.
Symptoms of melena
The clinical signs of melena are:
- the emission of black blood, accompanied by a foul odor, in the stool
- intestinal pain
Risk factors for melena
The main risk factors for melena correspond to the different possible causes. Either the presence of hemorrhages in the intestinal system, the presence of ulcers, colitis, etc.
How to treat melena?
The diagnosis of the disease is confirmed or ruled out as a result of endoscopy.
The management of treatment of lower bleeding depends on the origin of the bleeding. It can be a simple therapeutic treatment, endoscopic ablation, or a special diet to follow.
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