Blood after urination is not like menstruation

Blood is discharged from the anus, and the stool is bright red, dark red, or tarmac-like (melena), which is called blood in the stool. Blood in the stool is just a symptom, not a disease. Blood in the stool is common in lower gastrointestinal bleeding, especially bleeding from sigmoid colon and duodenal diseases, but it can also be common in upper gastrointestinal bleeding. The color of blood in the stool depends on the location of the bleeding in the digestive tract, the length of time the bleeding and blood stay in the digestive tract. Blood in the stool accompanied by bleeding of the skin, mucous membranes or other organs of the human body is common in blood diseases and other systemic diseases, such as sepsis, disseminated intravascular coagulation, etc.

1. Diseases of the digestive system itself, such as esophageal/gastric varicose veins with bleeding, stomach and intestinal ulcers and inflammation, sparganosis infection, tumors (including polyps and cancer), hemorrhoids, intussusception, anal fissures, constipation abrasions, etc.

2. Diseases of other systems besides the digestive system, such as blood diseases, acute infectious diseases, vitamin deficiency, poisoning or drug side effects, etc.

3. Blood in the stool in children and adolescents is mostly caused by intestinal polyps. The blood is bright red, painless, and does not mix with stool. It can also be seen in bacterial dysentery, intussusception, blood diseases, etc. Bloody stools in adults are mostly caused by hemorrhoids, anal fistulas, anal fissures, intestinal polyps, rectal cancer, inflammatory bowel disease, etc.

What are the clinical symptoms of blood in stool?

1. Fresh blood in the stool is mostly subacute (immediate) bleeding. The blood is discharged from the blood vessels and then discharged through the anus with excrement in a very short time, or immediately after defecation. The discharged blood looks similar to wound bleeding, with a bright red, purple or dark red color, and can coagulate into blood clots after a while. Common in the following diseases:

(1) Hemorrhoids of all ages, both internal and external hemorrhoids and mixed hemorrhoids can cause bleeding in the stool, usually with blood in the stool or blood dripping after defecation. External hemorrhoids generally do not cause bleeding in the stool.

(2) Intestinal polyps cause painless stool bleeding. Bleeding occurs during bowel movements and stops after bowel movements. The amount of blood varies. Generally, the blood does not mix with the feces, but if the polyps are located high and the number is large, they may also mix with the feces.

(3) Long-term rectal mucosal prolapse may cause bleeding during bowel movements. (4) Anal fissure with bleeding in stool. The bleeding method is that there is blood stain on one side of the surface of the feces, which does not mix with the feces. Some patients bleed after defecation.

2. Thick blood/mucus bloody stool means that the excrement contains pus (mucus) and blood. Purulent (mucous) and bloody stools are commonly seen in tumors and inflammation in the duodenum or sigmoid colon. The following symptoms are common:

(1) The blood of rectal cancer is fresh or dark red, and there will be mucus in the excrement. Usually, the blood, mucus and excrement are mixed together.

(2) As the history of colon cancer increases, bleeding in the stool will gradually occur, often with pus or blood in the stool containing thick fluid or mucus, and the blood is dark in color.

(3) Ulcerative colitis with mucus in the stool or mucus in the stool, accompanied by left lower abdominal pain or bloating. (4) Gastrointestinal infections such as bacterial dysentery, amoebiasis, etc.

3. Black stool is also called tarry stool, which is black or dark brown in color. It is one of the most common symptoms of upper gastrointestinal bleeding. If the bleeding is less and the bleeding rate is slower, the blood stays in the intestine for a longer time and the discharged feces is gray-black; if the bleeding is more and the waiting time in the intestine is shorter, the discharged blood is dark red; if the bleeding is very heavy and is discharged quickly, it may also be red.

4. Occult blood in urine and stool A small amount (small amount) of gastrointestinal bleeding is not likely to cause a change in stool color. It is only positive in the fecal occult blood test, which is called occult blood in urine and stool. All diseases that cause gastrointestinal bleeding can cause occult blood in the urine, common ulcers, inflammation and tumors. The fecal occult blood test detects small amounts of blood in the stool. The early stage of intestinal polyps (cancer) may show positive urine occult blood in feces. Regular urine occult blood test is an effective way to screen (primary screening) for colorectal tumors.