Sometimes conclusive diagnoses can be very difficult to reach. A few months ago I went the emergency room complaining of a shortness of breath. Four hours latter after a battery of tests including blood work, chest x-ray, cat scans, Covid test, etc., the doctor could find nothing wrong and told me the tests showed the body of a teenager. I am 84. Upon discharge I felt relieved that the tests did eliminate some of my fears of something terrible. My shortness of breath went away. I told my PCP in a followup visit that I think my GERD might have something to do with it. He didn't disagree.