Question Of The Day #92

This elderly patient arrives to the Emergency Department with painless hematochezia.  His exam shows borderline hypotension, tachycardia, and a normal abdominal exam.  This patient most likely has a lower gastrointestinal bleed based on his signs and symptoms.  A brisk (fast) upper GI bleed is also possible but is less likely.  Please refer to the chart below for a list of causes of GI bleeding, GI bleeding signs and symptoms, and the initial Emergency Department treatment of GI bleeding. 

All choices listed above are potential causes of bright red bloody stools.  Peptic ulcer disease (Choice C) is the most common cause of upper GI bleeding worldwide, not lower GI bleeding.  However, a profusely bleeding peptic ulcer can cause rapid blood transit through the GI tract to form hematochezia rather than melena.  The patient lacks any risk factors or symptoms of peptic ulcer disease, such as upper abdominal pain, hematemesis, NSAID use, or prior H. pylori infection.  Ischemic colitis, or mesenteric ischemia (Choice A), is often associated with abdominal pain and cardiac risk factors (i.e., atrial fibrillation).  Colon cancer (Choice B) is also possible, but typically colon malignancy causes slow, chronic bleeding, rather than acute large volume bloody stools with signs of shock as in this patient.  The most common cause of lower GI bleeding worldwide is diverticulosis (Choice D).  This is the most likely diagnosis in this patient with painless hematochezia.