Which symptom listed indicates GI bleeding, such as dark, tarry stool?

• A. Bright red blood in stool
• B. Pulsating abdominal mass
• C. Shortness of breath
• D. Dark, tarry stool

Answer: (D)

GI bleeding often shows up as changes in stool color. Dark, tarry stool, known as melena, occurs when blood from an upper GI bleed (stomach or duodenum) is digested as it passes through the digestive tract. The iron and enzymes darken the blood, giving stool a black, sticky appearance similar to tar. This makes it a strong sign of GI bleeding that has been present long enough for digestion to alter the blood. In contrast, bright red blood in stool suggests a bleed lower in the GI tract (or from hemorrhoids) where the blood hasn’t been digested. A pulsating abdominal mass points to an abdominal aortic aneurysm and isn’t a marker of GI bleeding, while shortness of breath is nonspecific and not diagnostic of GI bleeding by itself.