Melena: what does it involve?

It is an indicator that indicates bleeding inside the digestive tract, to be located and treated early.

The term melena indicates the presence of blood in the feces, which take on a dark color, a greasy (tarry) consistency and a bad smell. This aspect is conferred by the oxidation of hemoglobin by acidic juices and / or intestinal bacteria: melena suggests a relatively long stay (at least 8 hours) of blood in the intestine.

It is therefore not a disease but a sign, of which it is always advisable to look for the cause: in other words it is necessary to identify the site and the consequent extent of the bleeding, which could occur with a trickle or in more significant quantities.

There is another phenomenon that involves the presence of blood in the stool, hematochezia. Let’s see how the two disorders differ.

Appearance of feces What it indicates
Melena Dark
coloration Greasy texture
(tar)
Bad smell
A relatively long stay (at least 8 hours) of blood in the intestine
Hematochezia Bright red color It is an indication of a origin of the blood much closer to the anus, as for example in the case of hemorrhoids

Possible causes

The list of causes of melena is quite wide and heterogeneous: esophageal varices, gastritisgastric or duodenal ulcer, Crohn’s disease or ulcerative colitis, polyps, diverticula, gastrointestinal infections, pancreatitis, tumors are the most common factors, of which it is good to clarify some fundamental elements, such as the site (8 times out of 10 above the duodenum), the extension, the possible involvement of nearby structures, the course and so on.

Until a precise diagnosis is made, it is therefore not possible to establish the therapy or even to formulate a prognosis. It should also be considered that some conditions, such as ulcers and esophageal varices, can recur.

It is always good to check if it is really melena or not: an unusual and vaguely similar aspect of the feces can in fact be linked to the intake of iron, charcoal, licorice, beets or blueberries.

The clinical framework

Even before laboratory and instrumental tests, the general state of the individual is a very important indicator.

As mentioned and easily understood, slow bleeding is more likely to be discovered after some time, as most of the time it is accompanied by gradual anemization, while a massive, often sudden, loss can lead to rapid clinical decay, up to the risk of hemorrhagic shock, with the need for emergency surgery.

It should also be noted that melena, in at least half of the cases, is associated with haematemesis, i.e. vomiting with blood (in this case with an appearance mostly “coffee-bottom”, following gastric digestion).

Equally common is increased azotemia, due to intestinal absorption of hemoglobin and plasma proteins. A further element to consider is the pre-existence or presence of diseases, for example affecting the liver, kidney, digestive tract, coagulation system, or the practice of particular pharmacological, radio- or chemotherapy treatments.

Therapy

In the light of what has been explained so far, it is easy to understand why there is no univocal therapy. The priority objectives are, of course, the stabilization of general conditions (e.g. blood pressure), the prevention/correction of anaemia and the restoration of adequate coagulation. Therefore, depending on the case, pharmacological or surgical strategies will be chosen, in the presence of bleeding vessels, extensive ulcers or tumors.

Joycelyn Elders is the author and creator of EmpowerEssence, a health and wellness blog. Elders is a respected public health advocate and pediatrician dedicated to promoting general health and well-being.

The blog covers a wide range of topics related to health and wellness, with articles organized into several categories.

Leave a Reply

Your email address will not be published. Required fields are marked *