What is the reason for bloody stool

Many people will have bloody stools and diarrhea, so they will have symptoms of bloody stools. Too much or too little bloody stool will have different manifestations. The first common one is that the patient has anorectal diseases, because the rupture of hemorrhoids, local friction and ulcers will lead to symptoms of bloody stools. It is also not ruled out that there may be small intestine diseases, colon diseases, etc.

What are the causes of blood in the stool?

According to anorectal experts, blood in the stool is clinically divided into overt blood in the stool and covert blood in the stool based on the amount of bleeding. Overt blood in the stool means blood in the stool that can be seen with the naked eye; hidden blood in the stool means blood in the stool that cannot be seen with the naked eye but can be detected by experimental methods.

In addition, blood in stool can be divided into upper gastrointestinal bleeding and lower gastrointestinal bleeding according to the different bleeding sites. There are many causes of lower gastrointestinal bleeding, which can be divided into two categories: lower gastrointestinal diseases and systemic diseases according to the different primary diseases causing the bleeding.

1. Anal canal diseases

(1) Hemorrhoids: As the intra-abdominal pressure increases during defecation, the blood pressure in the internal hemorrhoidal venous plexus increases accordingly. In addition, the direct friction of hard feces causes the hemorrhoidal mucosa to rupture and bleed.

(2) Anal fissure: The anal mucosa and skin are torn by friction from hard feces during defecation, causing a small amount of bleeding.

2. Small Intestinal Disease

(1) Jejunal diverticulitis or ulcer: Bleeding due to inflammation of the diverticulum, erosion of the jejunal wall, or ulceration. Recommended reading: What is the disease of bleeding in stool? What are the inexpensive tests?

(2) Acute hemorrhagic necrotizing enteritis: The basic pathological changes are manifested as intestinal mucosal congestion, edema, bleeding and necrosis. The blood in the stool is often dark red or bright red paste-like blood with a special fishy smell.

3. Colon disease

(1) Acute bacillary dysentery: Bleeding due to extensive colon mucosal congestion, edema and even ulcers.

(2) Amebic dysentery: The intestinal wall is invaded by amoeba trophozoites, causing ulcers and bleeding.