Trust me when I tell you that a biopsy is not necessarily a definitive answer. I am soooooo upset right now, for I have suffered unnecessarily for 5 years now and nearly died because of this biopsies inaccuracy. I do have Celiac disease. It was the very first thing my Gastro suspected, had the endoscopy and the biopsy came back negative. He was stunned. Now some five years later, we know for sure I have it. I should have listened to my gut feelings (no pun intended all along) and maybe I wouldn't have had to suffer so needlessly all this time. It has been a living nightmare, not just with gastro problems, but excruciating pain throughout my body, rashes that never go away on my face, pain in my stomach that leaves me doubled over and my stomach distended, depression, fatigue, anxiety, it has been horrible! So I say yes, get the biopsy, but if it comes back negative and you still have all the classic symptoms, get a second opinion or procedure. It just may save your life, or at the very least the quality of your life.