There is a hemorrhoid patient in his 50s who has always been physically robust, but in the past two years he has often found some dark red blood on the surface of his stool, he always thought it was bleeding hemorrhoids, so he didn’t pay much attention to it, until once in a while he had a physical examination, and the colonoscopy found a surface erosion of a mass in the upper rectum that almost filled the intestinal cavity, and the biopsy pathology showed that it was adenocarcinoma of the rectum. When the doctor told him that he should have come for colonoscopy earlier, he looked very regretful and sighed “I didn’t know ……” Blood in stool: visible and invisible blood in stool, as the name implies, is blood in stool, medically the blood in stool that can be seen by naked eyes is called visible blood in stool. The blood in the stool that can be seen with the naked eye is called visible blood in the stool, while the one that cannot be seen with the naked eye is called occult blood in the stool. Blood in stool may be a sign of GI cancer, and sometimes it is the only sign of early stage cancer. Visible: black stool The most common form of blood in stool is black stool, except for blood that drips on the surface of the stool. After bleeding from the digestive tract, the outflowing blood decomposes iron in the esophagus, stomach to intestine, and combines with sulfide produced by bacteria to form iron sulfide and becomes black. When the amount of bleeding is more than 50 to 70 ml (a small teacup), black stool can appear; and when the stool is black and shiny like the kind of tar used for paving, it means that the amount of bleeding is about 100 to 500 ml (a bowl to a bottle), if 3 to 4 days in a row to solve the tar-like stool, it means that the amount of bleeding may reach more than 1000 ml, that is, about 1/4 of the total amount of blood, the patient may start to appear shock, need to The patient may be in shock and needs to be taken to the hospital immediately for emergency treatment. The invisible: occult blood Occult blood is the blood loss is too small or the blood has been decomposed and can not be identified by the naked eye, must be detected through the “fecal occult blood test”, but occult blood does not mean that the amount of bleeding is small, some patients with upper gastrointestinal tract (such as the stomach, biliary tract) bleeding, although the amount of bleeding, but the blood in the long journey from the esophagus to the anus has been broken down by digestive juices into a variety of The blood has been broken down into various fragments by the digestive juices during the long journey from the esophagus to the anus, and only through the occult blood test can we find traces of it. Generally speaking, if the amount of digestive bleeding in a day is more than 5 ml (one test tube), the occult blood will be positive, while the color of the stool can be unchanged. It should be reminded that a weakly positive occult blood test (a “+” on the test sheet) is not necessarily blood in the stool, but also in the diet of animal meat (mainly red meat), blood (the iron in meat and blood can also form black iron sulfide in the human intestine) or taking iron-containing drugs, which can also cause the illusion of occult blood. In addition, when these foods or drugs are taken in excess, they may also cause “false black stools”, which are mostly dull gray or dark black, and are not accompanied by any other uncomfortable symptoms. The “real culprit” of a disease is also hidden behind the blood in the stool, and in our lower GI tract, these “real culprits” are usually found in three segments. 1, anal segment The first to be included is the anal disease “gang”, because they are the most common repeat offenders of blood in the stool. Among them, the number of hemorrhoids “crime” the highest frequency. Hemorrhoids are a disease with a very high incidence, as the saying goes, “ten men and ten hemorrhoids, ten women and nine hemorrhoids”, hemorrhoids often cause a small amount of bright red blood on the surface of the stool and toilet paper, this bleeding is generally due to hard stool forced through the anus, damage to the small veins filled with hemorrhoids, bleeding is not much, often only a few drops, to not painful mostly. Anal fissures and fistulas are two other more common diseases of the perianal area that can present with small drops of blood after stool and are usually accompanied by more intense pain during or after stool. Anal fistulas are also seen with recurrent flowing pus openings around the anus with redness, swelling, and heat pain. It is important to emphasize that anal diseases do not exclude other causes of blood in the stool, but still need to do some tests to check. Colorectal segment Colorectum is what people usually call “large intestine”, which is a part with high incidence of cancer. Colorectal cancer is a common cause of blood in stool, accounting for about 30% to 50% of the cases of blood in stool in foreign countries, especially for the elderly. In addition to blood in stool, symptoms of colorectal cancer may include lower abdominal pain, diarrhea, constipation, thinning of stool, snot-like mucus in stool, urgency and heaviness, etc. In the advanced stage, patients may also show anemia such as emaciation or pallor, dizziness, etc. Intestinal polyp disease is also a common cause of blood in the stool, especially for children and adolescents. Bleeding from intestinal polyps is usually small, often a small amount of blood attached to the surface of the stool, with no other symptoms. Most intestinal polyps can be electrically removed endoscopically without hospitalization or surgery. Colonic vascular dysplasia, also known as colonic vasodilatation, is a common cause of acute or chronic blood in the stool in people over 60 years of age, and only occasional small amounts of blood in the stool generally do not require special treatment, while large amounts of bleeding require endoscopic hemostatic treatment. Acute and chronic enteritis is also a common cause of blood in the stool. Patients with chronic colitis also often have diarrhea, stomach pain, and other discomforts, and are generally in poor health, lethargic, with prolonged low-grade fever, etc. Some may also have depression and other psychiatric symptoms. Acute enteritis, such as dysentery and amebiasis, is usually caused by an unclean diet and can also present with blood in the stool and also with significant diarrhea. In the elderly, ischemic enteritis can be a cause of bloody diarrhea, and the disease is also seen in young women who often take birth control pills. 3, small intestine segment The small intestine is arguably the longest organ in the body, about 4 or 5 meters long. Many blood in the stool comes from the small intestine, the most common is small intestinal tumors, malignant slightly less than benign, accounting for about 2.5% of the entire intestinal tumors. Bleeding is often the first and only symptom of small intestinal tumors. Elderly people with small intestinal tumors combined with bleeding should be alerted to the possibility of malignancy. To identify the “three axes” of blood in stool, doctors generally have the most important “three axes” to check the list of “suspects” above blood in stool and find out the real culprit. 1, anal finger examination “the first axe”, the most simple and most important to be the anal finger examination. Do not underestimate the “one finger”, it can be said that the rectum within 8-10 cm from the anus is its “jurisdiction”, relying on it, 80% of rectal cancer can be diagnosed; various common diseases, such as hemorrhoids The second board of the anal speculum is the second board of the rectum. 2, anal peep “second axe” – anal peep, also known as anoscope, is also the anorectal department necessary “detection weapon”. Inspection of the doctor will be coated with lubricant mirror, slowly from the anus into the rectum after the insertion of the inner core, the outer casing gradually outward exit, in the spotlight irradiation of the rectum, the anal canal mucosa of the situation directly. It is an important tool to check internal hemorrhoids, anal fissures, rectal polyps, cancer, etc. The “one finger miracle” relies on the sense of touch, while it relies on vision, and the two just complement each other. 3, digestive endoscopy If the first two axes are not able to find the “real culprit”, then we need to use the most powerful “third axe” – digestive endoscopy, mainly gastroscopy, enteroscopy. The gastroscope looks a bit like the common weapon “whip” in martial arts novels. During the examination, the gastroscope is operated by the doctor like a whip with eyes, snaking into the gastrointestinal tract like a snake, and the high-definition images seen are displayed on the monitor in real time for the doctor’s observation. Gastroscopy is valuable for diagnosing patients with small to moderate amounts of blood in the stool. The power of gastroenteroscopy also lies in its ability to “scout” for disease, but also has the ability to “work on the spot”, and can endoscopically stop bleeding directly by electrocoagulation, hemostatic drug spray, sclerosing dose injection, and small vessel titanium clips. In the case of intestinal polyps, they can also be removed “in situ”. Blood in the stool is a very common symptom, when found should not be nervous panic, nor should you let down your guard, you should promptly go to the hospital, through the doctor’s “three axes” examination, to find the “real culprit”, to get targeted treatment, to get good The treatment effect.