From the Guidelines
The medical term for rectal bleeding, or blood in stool, is hematochezia. This refers specifically to the passage of fresh, red blood from the rectum, often mixed with or coating the stool. Hematochezia typically indicates bleeding from the lower gastrointestinal tract, such as the colon or rectum. Common causes include hemorrhoids, anal fissures, diverticular disease, inflammatory bowel disease, polyps, or colorectal cancer. The bright red appearance distinguishes it from melena, which refers to black, tarry stools resulting from upper gastrointestinal bleeding where blood has been partially digested.
Key Considerations
- Any instance of blood in stool should prompt medical evaluation, as it can range from benign conditions like hemorrhoids to more serious issues requiring immediate treatment.
- The color, amount, and accompanying symptoms help physicians determine the source of bleeding and appropriate treatment.
- Even small amounts of rectal bleeding should not be ignored, especially in individuals over 40 or those with a family history of colorectal cancer, as noted in recent guidelines 1.
- A precise patient history and a careful physical examination are essential for accurate diagnosis, as emphasized in the American Gastroenterological Association technical review 2.
Diagnostic Approach
- Current practice guidelines from both the American Society for Gastrointestinal Endoscopy and the Society for Surgery of the Alimentary Tract advocate a minimum of anoscopy and flexible sigmoidoscopy for bright-red rectal bleeding, as discussed in 2.
- Complete colonic evaluation by colonoscopy or air-contrast barium enema is indicated when the bleeding is atypical for hemorrhoids, when no source is evident on anorectal examination, or when the patient has significant risk factors for colonic neoplasia.
- The decision to pursue further evaluation also depends on the patient’s age and general medical condition, highlighting the importance of a tailored approach based on individual patient factors 3.
Recent Guidelines and Recommendations
- The most recent guidelines from 2021, such as those from the World Journal of Emergency Surgery 4 and the Journal of the American College of Radiology 1, emphasize the importance of prompt evaluation and appropriate management of lower gastrointestinal tract bleeding.
- These guidelines suggest the use of ano-proctoscopy or flexible sigmoidoscopy as the first-line diagnostic tool for suspected bleeding anorectal varices and recommend urgent colonoscopy within 24 hours of presentation for patients with high-risk features or evidence of ongoing bleeding 4.
From the Research
Definition of Rectal Bleeding
- The term for rectal bleeding, or blood in stool, is referred to as hematochezia 5, 6, 7, 8.
- Hematochezia is defined as the passage of blood or clots from the rectum 5.
Characteristics of Hematochezia
- Hematochezia can be quite alarming and is a common complaint in adult patients 5, 6.
- It is characterized by the passage of bright red blood per rectum 7.
- The bleeding can be associated with various underlying conditions, including anal causes, colorectal cancer, hemorrhoids, and other gastrointestinal pathologies 5, 9, 6, 7, 8.
Clinical Evaluation of Hematochezia
- The evaluation of hematochezia involves a detailed medical history, physical examination, and diagnostic tests such as colonoscopy and anoscopy 9, 6, 7.
- Clinical symptoms associated with hematochezia, such as the amount and frequency of bleeding, weight loss, and change in bowel habits, can provide valuable information for diagnosis 7.
- However, the physician's clinical assessment may not reliably predict the presence of substantial pathology, and further diagnostic testing is often necessary 7.