During my upper gi endoscopy they tested for h. phloryi but it came back negative. could my ppi have given a false negative? gerd symptoms worsening

Endoscopy & Hpylori: An upper endoscopy essentially takes a few samples of tissue from the stomach and tests them for H. pylori. This test shouldn't be affected by a PPI as it examines for the bacterium under the microscope. It doesn't always detect H. pylori even if it is there because you are just spot-testing areas of the stomach, and without bleeding, is about 70% reliable.