Bloody stools

Blood in stool looks different depending on how early it enters the digestive tract—and thus how much digestive action it has been exposed to—and how much there is. The term can refer either to melena, with a black appearance, typically originating from upper gastrointestinal bleeding; or to hematochezia, with a red color, typically originating from lower gastrointestinal bleeding. Evaluation of the blood found in stool depends on its characteristics, in terms of color, quantity and other features, which can point to its source, however, more serious conditions can present with a mixed picture, or with the form of bleeding that is found in another section of the tract. The term 'blood in stool' is usually only used to describe visible blood, and not fecal occult blood, which is found only after physical examination and chemical laboratory testing. Blood in stool looks different depending on how early it enters the digestive tract—and thus how much digestive action it has been exposed to—and how much there is. The term can refer either to melena, with a black appearance, typically originating from upper gastrointestinal bleeding; or to hematochezia, with a red color, typically originating from lower gastrointestinal bleeding. Evaluation of the blood found in stool depends on its characteristics, in terms of color, quantity and other features, which can point to its source, however, more serious conditions can present with a mixed picture, or with the form of bleeding that is found in another section of the tract. The term 'blood in stool' is usually only used to describe visible blood, and not fecal occult blood, which is found only after physical examination and chemical laboratory testing. In infants, the Apt test can be used to distinguish fetal hemoglobin from maternal blood based on the differences in composition of fetal hemoglobin as compared to the hemoglobin found in adults. Blood in the stool can come from many sources. The causes range from not harmful to very serious conditions. A common way to divide causes of bleeding is based on the source of bleeding. The GI tract can be divided into upper and lower, with some causes of bleeding affecting the entire tract (upper and lower). Blood in the stool often appears different depending on its source. These difference can help when diagnosing these conditions. The rate of bleeding can also make blood in the stool look different from typical cases. The upper GI tract is defined as the organs involved in digestion above the ligament of Treitz and comprises the esophagus, stomach, and duodenum. Upper gastrointestinal bleeding is typically characterized by melena (black stool). Bright red blood may be seen with active, rapid bleeding. Bleeding of the lower GI tract will typically appear as hematochezia and can vary in degree of seriousness. Slow bleeding from the ascending portion of the colon can result in partial digestion of the blood and the appearance of melena in the stool. The development of blood in a person's stool results from a variety of conditions, which can be divided into major categories of disease. These broad categories include cancerous processes or abnormal structure of bowel wall, inflammatory disease, colitis caused by infection or medications and vascular compromise. The gut wall is important for the movement of waste products through the GI tract. Repetitive attempts to have a bowel movement can lead to tearing around the exit of the rectum (anal fissure) This list of diagnoses include diseases in which the wall of the bowel is compromised by disease. Diseases causing inflammation in the GI tract can lead to blood in the stool. Inflammation can occur anywhere along the GI tract in Crohn's disease, or in the colon if a person has ulcerative colitis.