Black stool or medically known as “melena”, is the passage of black tarry feces. It is often confused with hematochezia which is fresh blood in the stool.
The difference between black stool and bloody stool is that the bleeding or the bright red blood coming from the lower gastrointestinal tract is called hematochezia while on the other hand, the blood or black stool that comes from a high source such as the small intestine can be considered to be melena.
Black stool is oftentimes associated with gastrointestinal hemorrhage. There are some cases however that hemorrhage from the upper gastrointestinal tract is not visible, thus it is termed as occult blood and the blood can only be detected through the feces or stool.
The bleeding from Melena is slow, that is why it is often not considered as a medical emergency. It is diagnosed with a blood test of the fecal occult that measures the amount of blood present in the stool.
Black Stool Causes
Black stool or melena can have a variety of causes and they are as follows:
- Bleeding Ulcers- Ulcers can cause bleeding on the inner lining of our stomach. Peptic Ulcer is the most common cause of Melena.
- Esophageal Varices- the veins of the lower esophagus are enlarged and swollen due to portal hypertension that can rupture. When the veins ruptured, the blood can be seen either in the feces or vomitus.
- Gastritis- Inflammation of the lining of the stomach caused by spicy food, smoking, acholol use and infections caused by bacteria.
- Long term use of NSAIDS- pain medications that causes ulcer in the stomach that can eventually lead to black stool.
- Upper GI trauma
- Foreign body either in the stomach or the intestines
- Cancer of the colon (COLORECTAL CANCER)
Black Stool in Children
Most often, parents are alarmed when they notice the presence of blood and or their child’s stool is black. Black stool is not always a sign of a serious illness or diseases.
The most common cause of black stool in children is Anal Fissure. It is a painful ulceration or laceration on the lining at the margin of the anus. If the black stool is not associated with diarrhea, most children with blood stool may have anal fissures. Anal fissure occurs as a result of passing stools that are hard and large.
Black Stool Diarrhea
Diarrhea or Loose Bowel Movement (LBM) is the passage of a loose watery stool that often occurs 3-4 times in a day. It is a common problem for most of us. Often times, it does not require any treatment but for those that does not resolve after 2 days, immediate intervention is needed.
The cause of black diarrhea can be an infection, food intolerance, side effects of medication such as drug medication and iron pills, and bleeding from the stomach. The condition may be accompanied by fever, dehydration, severe pain and sometimes accompanied by black stool.
The diarrhea itself would require consulting a physician most especially if with black stool.
References
http://en.wikipedia.org/wiki/Melena
http://www.nlm.nih.gov/medlineplus/ency/article/003130.htm
http://www.kidsgrowth.com/resources/articledetail.cfm?id=1948
