Patient's question:
Main symptoms: Blood in stool, abdominal pain, diarrheaOnset time: 5 a.m. today
Laboratory test results:
Doctor's answer:
Hematochezia (hidden blood in stool) is mostly associated with digestive system diseases. Hematochezia, which is gastrointestinal bleeding excreted through the intestines, results in blood-streaked or completely bloody stools, with colors ranging from bright red to dark red and black tar-like. The color of bloody stools depends on the location of bleeding, the amount of bleeding, and the time the blood stays in the digestive tract. Lower gastrointestinal bleeding (small intestine, colon, rectum, anus) often results in bright red or dark red stools. Upper gastrointestinal bleeding (esophagus, stomach, duodenum) often results in black tar-like stools.### (I) Etiology
Hematochezia is generally classified into fresh blood stools, black tar-like stools, and hidden blood stools. The common causes are described as follows:
1. Fresh blood stools: Usually originate from the distal ileum, colon, rectum, or anus, with bright red or dark red stool, which may contain mucus and purulent blood. Common diseases include:
- Hemorrhoids
- Anal fissure bleeding
- Hemorrhoidal bleeding may spray out during defecation or drip after defecation.
- Anal fissure bleeding is usually minimal but accompanied by severe anal pain.
- Rectal polyps bleeding, with small amounts of blood attached to the stool surface, sometimes causing the stool to narrow into strips or leave pressure marks.
- Dysentery, presenting as purulent bloody stools, frequent bowel movements, and left lower abdominal pain.
2. Black tar-like stools (melena): Occurs when upper gastrointestinal bleeding is not vomited, and the blood stays in the intestines for a long time. Hemoglobin in the blood combines with sulfur compounds in the intestines to form ferrous sulfide, which makes the stool black and shiny, resembling tar. The appearance of black tar-like stools indicates bleeding of more than 60 milliliters. However, certain foods or medications can also turn the stool black, so a fecal occult blood test can help differentiate.
3. Hidden blood stools: Occur when small amounts of gastrointestinal bleeding do not change the stool color but result in a positive fecal occult blood test. All diseases that cause gastrointestinal bleeding can lead to hidden blood stools. Common causes include:
- Gastric ulcers
- Gastric cancer
### (II) First Aid Measures
First aid measures are similar to those for hematemesis. Rest quietly in bed, reduce activity, monitor the amount of bleeding, use appropriate hemostatic drugs, and seek emergency medical attention promptly if fainting or shock occurs.
### How to Register for an Appointment
1. Colorectal Surgery: Patients with fresh red blood after defecation or bright red bloody stools without severe abdominal pain should register under Colorectal Surgery.
2. General Surgery: Patients with fresh bloody stools accompanied by severe abdominal pain or shock should register under General Surgery.
3. Gastrointestinal Outpatient Clinic: Patients with acute onset and purulent bloody stools should register under the Gastrointestinal Outpatient Clinic.
4. Gastroenterology: Patients with black stools, dark red bloody stools, or a history of chronic colitis with frequent bright red bloody stools should register under Gastroenterology.
5. Hematology: Patients with hematochezia and a tendency to bleed throughout the body should register under Hematology for further examination.
6. Nephrology: Patients with a history of nephritis who also develop blood in their stools should register under Nephrology.
7. Infectious Diseases: Patients with hematochezia after fever and a history of living in an epidemic area should register under Infectious Diseases.
Hematochezia refers to blood discharged from the anus, including dripping blood during defecation, spraying blood, or blood-streaked stools. Generally, visible hematochezia suggests lower gastrointestinal bleeding (especially from the colon and rectum). The closer the bleeding site is to the anus, the brighter the blood color.
It is a common misconception that hematochezia is always caused by hemorrhoids. Hemorrhoids, especially first- and second-degree internal hemorrhoids, often present with hematochezia as the primary symptom. Hematochezia usually occurs during defecation, with dripping or spraying blood that does not mix with the stool. The amount of bleeding varies, ranging from several milliliters to tens of milliliters. Repeated bleeding can lead to severe anemia.
The diagnosis of hemorrhoids is relatively straightforward, but it is important to note that conditions like rectal adenomas or rectal cancer with hematochezia are often misdiagnosed as internal hemorrhoids. Therefore, when diagnosing hemorrhoids, other diseases must be ruled out. Digital examination of patients with hematochezia is necessary. Routine examination using a disposable sigmoid colon scope is a convenient, cost-effective, safe, and accurate method.