Alternative Name for Hematochezia
Hematochezia is also called "bright red blood per rectum" or simply "rectal bleeding." 1
Clinical Definition
Hematochezia specifically signifies the passage of bright red blood or blood clots from the rectum, distinguishing it from melena (darkened, digested blood). 1, 2
Key Terminology Points
- The term "hematochezia" is defined as the passage of blood or clots from the rectum in clinical practice 2
- This is distinct from melena, which refers to black, tarry stools indicating digested blood from an upper gastrointestinal source 1
- The bright red appearance indicates that blood has not been exposed to gastric acid long enough for digestion, suggesting a lower GI source (distal to the ligament of Treitz) 1
Important Clinical Caveat
Approximately 10-15% of patients presenting with acute severe hematochezia actually have an upper gastrointestinal source of bleeding identified on upper endoscopy, particularly when bleeding is massive and transit time is rapid. 1 This occurs because rapid transit through the GI tract prevents blood from being digested into melena, even from proximal sources like duodenal ulcers. 3