Colorectal bleeding, what diseases to consider?

Lower gastrointestinal bleeding (LGIB) accounts for 20%~30% of all gastrointestinal bleeding, which is defined as intestinal bleeding distal from the ligament of Curl, including small intestinal bleeding and colorectal bleeding
.

Among them, colorectal bleeding is one of the
common clinical critical diseases in gastroenterology.

So, what diseases should be considered in patients experiencing colorectal bleeding?

The typical clinical manifestations of patients with colorectal bleeding are: sudden onset of blood in the stool, that is, dark red or bright red blood is excreted through the rectum, and large bleeding can be accompanied by signs of peripheral circulatory failure such as dizziness, dark cloud, pallor, increased heart rate, and decreased blood pressure
.

However, in rare cases, patients with bleeding from the right colon may present with melena.

In addition, hematochezia may also be found in patients with acute upper GI bleeding, and approximately 15% of patients with hypothetical acute lower GI bleeding eventually find that the bleeding originates from the upper GI
tract.

Bleeding from diseases such as hemorrhoids and fissures is also very common clinically, and bleeding caused by
diseases should be excluded when diagnosing acute lower gastrointestinal bleeding (colorectal).

Patients with colon malignant tumors often have fatigue, weight loss, and changes in stool habits, drug-related colorectal bleeding patients often have a clear drug history, and patients with ischemic colitis often have sudden spastic abdominal pain
before blood in the stool.

Common diagnostic methods for colorectal bleeding are:

Imaging examination: imaging examination is an important means
for diagnosis and localization of colorectal bleeding.
Commonly used imaging methods include abdominal contrast CT, abdominal CT angioreconstruction, X-ray barium angiography, radionuclide scanning, selective arteriography and so on
.

Endoscopy: Colonoscopy is the most important means of determining the cause and location of colorectal bleeding, and can be treated with direct endoscopic hemostasis
.

References:

1.
ZHU Yueyong,ZHUANG Zehao,DONG Jing.
Gastroenterologist Ward Rounds Manual (2nd Edition)[M].
Beijing:Chemical Industry Press,2017.

2.
Colorectal Group, Digestive Endoscopy Branch of Chinese Medical Association, Colorectal Group of Gastroenterologist Branch of Chinese Medical Doctor Association, National Clinical Research Center for Digestive Diseases.
Guidelines for the diagnosis and treatment of lower gastrointestinal bleeding(2020)[J].
Chinese Journal of Digestive Endoscopy,2020,37(10):685-695.
)