You can have celiac disease and have a negative antibody test. And you can have gluten sensitivity, which doesn't show up on an antibody test. In addition, the genius gastros have decided that the Reticulin Antibody doesn't need to be done anymore, even though it's sensitive and specific for CD and it tests a different protein/antigen reaction. My Reticulin was positive. If you have concerns about it, you can see a gastroenterologist for more info.

Oh, also if you have a low IgG level, it can affect the test and make it look like a false negative. Same with MG and a low IgA level.