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In medicine, Melena(medicine)
In Citys, Melena del Sur, Cuba

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+{{Disambiguation}}
-{{DiseaseDisorder infobox |
-  Name        = Melena |
-  ICD10       = {{ICD10|K|92|1|k|90}} |
-  ICD9        = {{ICD9|578.1}} |
-}}
+In [[medicine]], [[Melena(medicine)]]<br />
-In [[medicine]], '''melena''' or '''melaena''' refers to the black, "tarry" [[feces]] that are associated with gastrointestinal [[hemorrhage]]. The black color is caused by oxidation of the [[iron]] in [[hemoglobin]] during its passage through the [[ileum]] and [[colon (anatomy)|colon]].
+In Citys, [[Melena del Sur, Cuba]]
-==Melena vs. hematochezia==
-Bleeding originating from the lower GI tract (such as the [[sigmoid colon]] and [[rectum]]) is generally associated with the passage of bright red blood, or [[hematochezia]], particularly when brisk.  Blood acts as a [[cathartic (medicine)|cathartic]] agent in the intestine, promoting its prompt passage.  Only blood that originates from a high source (such as the [[small intestine]]), or bleeding from a lower source that occurs slowly enough to allow for oxidation, is associated with melena.  For this reason, melena is often associated with [[blood]] in the [[stomach]] or [[duodenum]] ([[upper gastrointestinal tract]]), for example by a [[peptic ulcer]].  A rough estimate is that it takes about 14 hours for blood to be broken down within the intestinal lumen; therefore if transit time is less than 14 hours the patient will have hematochezia, and if greater than 14 hours the patient will exhibit melena.  One often-stated rule of thumb is that melena only occurs if the source of bleeding is above the [[suspensory muscle of the duodenum|ligament of Treitz]].
-==Diagnosis==
-Patients present with signs of [[anemia]].  The presence of blood must be confirmed with either a positive hemoccult slide on rectal exam, frank blood on the examining finger, or a positive stool guaiac from the lab.  If a source in the upper GI tract is suspected, an [[upper endoscopy]] can be performed to diagnose the cause.  Lower GI bleeding sources usually present with hematochezia or frank blood.  A test with poor sensitivity/specificity that may detect the source of bleeding is the [[tagged red blood cell scan]], whereas [[mesenteric angiogram]] is the gold standard.
-==Causes==
-The most common cause of melena is [[peptic ulcer]] disease. Any other cause of bleeding from the upper gastro-intestinal tract, or even the ascending colon, can also cause melena.  Melena may also be a sign of drug overdose if a patient is taking anti-coagulants, such as warfarin. It is also caused by tumours especially malignant tumors affecting the esophagous,more commonly the stomach & less commonly the small intestine due to the bleeding surface of them. However,the most prominent and helpful sign in these cases of malignant tumours is [[haematemesis]]. It may also accompany hemorrhagic blood diseases (e.g. [[purpura]] & [[hemophilia]]).
-Melena is usually not a [[medical emergency]] because the bleeding is slow.  Urgent care however is required.
-A less serious, self-limiting case of melena can occur in newborns two to three days after delivery, due to swallowed maternal blood.
-==See also==
-* [[Blood in stool]]
-* [[Hematemesis]]
-* [[Dieulafoy's lesion]]
-{{Gastroenterology}}
-{{Unreferenced|date=December 2006}}
-[[Digestive disease symptoms]]
-[[Category:Symptoms]]
-[[Category:Feces]]
-{{symptom-stub}}
-[[de:Teerstuhl]]
-[[es:Melena (medicina)]]
-[[fr:Melæna]]
-[[hr:Melena]]
-[[it:Melena]]
-[[nl:Melena]]
-[[ja:メレナ]]
-[[pl:Stolec smolisty]]
-[[pt:Melena]]
-[[ru:Мелена]]
-[[sk:Meléna]]