Itchy mouth after apples?

A patient recently complained that they bit into a red apple and within a few minutes started to have intense itching of their tongue, throat and roof of their mouth.  They were also having some horrendous seasonal nasal allergy symptoms, which didn’t surprise me as this has been a very bad spring pollen season.  It turns out that many patients with seasonal allergic rhinitis experience itching of the oral cavity after eating certain foods that share common proteins with pollens.  This has been found to be most common with birch tree pollen (spring pollen), grass (summer pollen), and ragweed (fall pollen).  Patients with birch allergy often have oral itching after eating apples, pears, peaches, kiwi, celery, and parsley.  Patients allergic to grass may react to peach, celery, and tomato.  Finally, ragweed-sensitive patients may have these same oral symptoms after eating bananas, melon, and tomato.  Importantly, heating any of these foods at high temperature eliminates the allergenic proteins, so my patient would probably tolerate apple pie.  If you’ve noticed these symptoms in response to any of these foods, refrain from eating it and check with your doctor about the safety of eating it in the future.

How bad is gluten?

Over the past decade, gluten has gotten a bad name.   Gluten is a protein that occurs naturally in wheat, rye and barley.  Approximately one percent of Americans develop a condition called celiac disease, which is due to an allergic-like reaction to gluten and is characterized  by symptoms of bloating, pain and diarrhea.  The majority of patients who have suspected that they have problems with gluten have negative blood tests for celiac disease, leaving doctors to scratch their heads.  Our thinking about this may be about to change.  Based upon recent research from the University of Maryland’s Celiac Research Center,  up to 7% of people living in the United States have a condition called “gluten sensitivity”, in which they have abdominal symptoms after eating wheat and other gluten-containing foods but do not have a positive blood test for celiac disease.  As of yet, there is no diagnostic test for gluten sensitivity, and the diagnosis is based primarily upon a careful clinical history, physical examination, general blood tests, and possibly upon a period of gluten avoidance followed by re-introduction