By Dr. Paul Ehrlich
A letter by several eminent allergists* in the Journal of Allergy and Clinical Immunology (JACI) highlights the use of the oral food challenge (OFC), measured by response to questionnaires. This is a fascinating little piece, giving insight into holes in allergy training (only 45% reported having personally performed challenges during their fellowships) and the role that money plays in deciding whether to do this time-consuming procedure.
“The top 3 perceived barriers to performing OFCs were time, inadequate reimbursement, and risk of an adverse event. Indeed, the survey disclosed that the duration of the procedure is most often 3 to 4 hours, with significant use of the allergist and additional office staff for preparation and supervision.”
Yet, as the letter states, food challenges are “crucial in identifying children who were otherwise following unnecessary dietary restrictions based on the results of in vitro testing.” As I have written before, parents (and patients) are frequently so wary of the sensitivities indicated by blood tests that they will limit diets to the point of malnutrition. If I have any criticism of the letter, it doesn’t give a clear accounting of when OFC might reasonably be used in treatment. An OFC is not a screening tool. It is there to confirm an allergist’s clinical judgment based on a thorough history, other test results, and years of training. Of course, a professional journal can assume its readers know this.
That said, the situation on the ground often looks very different than from 30,000 feet. These are the factors that play a part in my office:
Fear born of experience: Having experienced or witnessed one or more episodes of anaphylaxis, patients or patients’ parents are extremely reluctant to risk it happening again.
Nothing but the best: As a specialty we have done such a good job of selling Double Blind Placebo Controlled Food Challenges (DBPCFC) as the “gold standard” parents are reluctant to settle for second best—the non-blinded tests that allergists do in the office. The DBPCFC is just too labor intensive and time consuming for an office practice and must generally be done in a specially equipped academic setting.
Won’t take yes for an answer: After 35 years of practice, my own judgment about when the danger is past for a child is pretty good, if I do say so myself. I will give clearance to reintroduce foods at various points, which often happens when there has been accidental exposure without incident. Yet, Mom is often reluctant without the safety of an office challenge; I would guess that they follow through at home maybe 5 percent of the time. Even after an office challenge, it’s often not enough, particularly with peanuts. After years of abstinence and anxiety, I can recall only one patient who started eating peanuts, and that was a very special case, which you can read about here.
* Jacqueline A. Pongracic, MD, S. Allan Bock, MD, Scott H. Sicherer, MD
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