Stool Colors and What They Can Tell You Your stool color can carry important clues about digestion, diet, or even disease. Most shades are harmless, but some changes signal the need for Melena Stool Definition, Causes and More: Understand melena stool, dark and tarry stool often indicating upper gastrointestinal bleeding. Learn about potential causes and implications.: Arpilor, Mr. Leonardimer: 9798859376544: Amazon.com: Books What is the cause of recurrent melena stool with multiple telangiectasia and prominent veins in the proximal ascending colon in a 14 year old boy? Melaena Causes Diagnoses Management TeachMeSurgery