food allergy clinic

The core role of food allergy clinics is never to prescribe long lists of taboos to patients, but to help patients distinguish between “true allergies” and “false intolerances” through accurate testing and clinical assessment, and to maximize dietary freedom while avoiding the risk of allergies.

I had a consultation last Wednesday, and the first person who came in was a mother holding a 3-year-old boy. She had nearly twenty allergen report sheets from different institutions stuffed in her bag. Her eyes turned red as soon as she sat down: "Doctor, my baby can only eat cabbage, pork, and rice every day. I dare not give him eggs, milk, or wheat. He has not grown at all in the past six months. What else can he eat?" ”

This is also the stereotype that most people have about food allergy clinics: they come here just to check “what they can’t eat” and end up going home with a half-page list of taboos, thus being cut off from many of their favorite foods. But to be honest, the work we do most in the outpatient clinic is called "lifting the ban" - for this mother's baby, all the more than a dozen allergens tested in different institutions were weakly positive, and he was required to avoid all categories. We combined the medical history to do skin pricks and serum-specific IgE tests, and finally did an oral food challenge test. It was confirmed that he only had an immediate allergy to milk, and other eggs, wheat, seafood, etc. were all false positives and did not need to be avoided at all. Half a month later, my mother came for a follow-up consultation. The baby carried half a steamed egg and chewed it all over his face. He gained two pounds in half a month.

Speaking of this, I have to mention the food-specific IgG test that is currently making a lot of noise on the Internet. Some people say it is a pure IQ tax, while some people rely on its results to cure constipation and acne all year round. There is a lot of quarrel between the two sides. Objectively speaking, the current mainstream consensus among allergy departments in China is that IgG test results cannot be used as a basis for diagnosing food allergy. In essence, it can only reflect that your immune system has been exposed to this food, and does not mean that it will induce allergic reactions. ； However, many doctors in the nutrition department and gastroenterology department will use it as a reference indicator for chronic food intolerance to adjust the diet structure. The current routine practice in our outpatient clinic is that we will never tell patients to avoid eating just by looking at an IgG report. All conclusions must be combined with the disease history and other test results, and finally rely on the "gold standard" oral food challenge test.

There was a young man who was a sophomore in college. He had been eating mangoes for more than ten years and was fine. Last time he and his roommate went to the orchard and picked half a bag of green mangoes. After eating, his mouth became swollen. He went to a private institution for an IgG test, and the mangoes showed 3 plus signs. He was told by the doctor that he "cannot touch mangoes in this life." He cried. He came to our clinic with a sad face, and after the provocation test was completed, he found that eating a whole ripe Tainong was fine. The so-called "allergy" last time was actually due to the aldehyde acid in the green mango irritating the oral mucosa. In addition, he stayed up late to review and his immunity was low, so it had nothing to do with allergies. When the young man got the result, he went to the fruit shop at the door and bought two large mangoes, and gnawed half of one while standing in the corridor.

There is currently a controversial direction in the academic community, which is the oral immunotherapy of food allergy: simply put, allergy patients are allowed to ingest allergens from a small dose, and gradually increase the amount to help the body build tolerance. Many children with severe milk allergies and egg allergies can finally eat normally through this method, but many experts are opposed to it. They believe that this method has a high risk of inducing severe allergic reactions. Patients whose allergic symptoms do not affect their normal life do not need to take this risk. The current principles of our outpatient clinic are also very flexible. If the patient is so severe that he goes into shock when exposed to a little allergen, or even affects his growth and development, we will try to provide tolerance treatment under full supervision. ； If you just have a rash after eating it and it does not affect your normal life, it is generally recommended to avoid it on a daily basis. There is no need to take risks just for one bite.

Not long ago, I treated a 26-year-old girl. Because of recurring acne on her face, she spent half a year doing popular science on the Internet. She also stopped eating sugar, milk, and gluten for three years. She didn’t even touch cakes, milk tea, bread, or noodles. When she came for a checkup, her face was a little gray. In the end, after making the whole set, she was only mildly sensitive to the gluten of incompletely fermented raw wheat. As long as she did not eat freshly baked bread or freshly rolled raw noodles, fermented steamed buns, bread that had been stored for more than 24 hours, and ordinary noodles were all fine. She walked out of the outpatient clinic that day and went straight to the nearby shopping district to buy a cup of full-sugar pearl milk tea. She sent me a message in the evening and said that she almost cried when she took the first sip, "It turns out that I was hungry for three years."

I have been in the food allergy clinic for almost five years, and I have seen too many patients who frightened themselves: either they blacklisted half of the food after reading two pieces of popular science, or they still had blood after drinking milk, and they were sent to the emergency room for anaphylactic shock. In fact, food allergies are both serious and simple. When you are not sure, coming to the clinic and chatting for half an hour is much more effective than watching three days of short video popularization. After all, we are not here to put you in a shackles of diet. We are here to help you figure out what you should avoid and what you can eat with confidence. Being able to eat what you like in a down-to-earth manner is the most practical thing in life.