what test to ask for to diagnose?

Thanks, KO

Wheat allergy:  Anti-Wheat IgE and IgG  (be sure they look at both...IgE is immediate hyersensitivity, IgG is delayed hypersensitivity), and/or skin scratch test for wheat.

Gluten sensitivity:  Anti-Gliadin IgG.

Celiac:  Anti-Gliadin IgA, Anti-Gliadin IgG, total IgA, Anti-Tissue Transglutaminase antibodies, and sometimes Endomysium antibodies.

Special stool studies and/or genetic tests can also help confirm a diagnosis of Gluten Sensitivity - see http://www.enterolab.com/

Also, for the "Gold Standard" Celiac diagnosis, one must show villous atrophy on biopsy of the small intestine (this requires an endoscopy procedure done by a Gastroenterologist).

Dietary gluten avoidance (minimum 3-6 months - because it can take that long for the gut to heal after gluten has been removed from one's diet), followed by a gluten challenge (eat 1 thing containing gluten, such as a cookie or piece of bread), can sometimes reveal a gluten problem that is unable to be detected via blood test, stool test, or small bowel biopsy.  This method can also be used to confirm a diagnosis if tests are inconclusive.

The best info I know of on all this stuff can be found at The Gluten File - see http://sites.google.com/site/jccglutenfree/

Also, it is known that Lyme disease can trigger a form of gluten sensitivity that may or may not go away with treatment.  And some doctors theorize that Celiac disease can be triggered by an infectious agent...

I hope this helps...take care,

Yes, it is possible to feel relief pretty quickly upon going on a gluten-free diet.  This can be the case whether one has a wheat allergy, gluten sensitivity or Celiac.

Yes, congestion is a possible symptom of some kind of immune response to wheat (be it allergy, sensitivity or Celiac).  More recent research shows that the gut is not the only organ affected by people with Celiac - sometimes, the damage shows up in the nervous system in addition to or instead of the gut (e.g., gluten ataxia, seizure disorders, etc.).  As for allergy (whether it is immediate or delayed), sinus congestion is a common symptom.  

Gluten/Wheat sensitivity is somewhere in-between an allergy and Celiac (autoimmune) in that it involves the immune system, but not the classic IgE antibodies...and some with Gluten Sensitivity may even be considered to be "early Celiac" because they have only mild gut damage and not enough anti-tissue transglutaminase or anti-gliadin IgA antibodies in the blood to qualify them for the full-blown Celiac diagnosis, but clearly the gut is being damaged...these people often show up as positive on the stool studies due to the increased sensitivity of the stool tests vs. the blood tests for anti-gliadin and anti-tissue transglutaminase antibodies.  The symptom picture of Gluten Sensitivity can be much broader than Celiac, and sinus congestion can certainly occur as part of this.

I hope this helps...take care,