@pwgrimes- the word celiac itself is referring to something abdominal.
Celiac disease is an abdominal disease. The celiac artery supplies blood to intestines and abdominal organs.
If the celiac artery is compressed, there is not enough blood for intestines to do work needed for digestion- therefore pain that is similar to pain when coronary artery is blocked- angina.
Celiac disease is difficult to diagnose at times and is difficult to live with. My two daughters have celiac disease. I agree that there is not much information about it- many doctors are not aware of how common it is.