food allergy doctor

Many people think that the job of a food allergy doctor is to prescribe allergen tests and make a fasting list. In fact, this is not the case - our core job is to help people with food allergies reestablish a safe relationship with food, rather than pushing them into a cage of "they can't eat this or touch that."

Last week, we met a 3-year-old patient in the outpatient clinic. Her grandma came in with her mouth still red. She said that she swollen like this after eating a mouthful of mango in the morning. The first thing she said when she came in was, "Doctor, we will never touch mangoes to my baby again. Please list all the things he can't eat. We will never touch them." I did a prick test on the child, asked about his previous dietary history, and told grandma that it was just contact dermatitis irritated by mango acid, not an allergy. The next time he ate it, cut it into small pieces and put it directly into his mouth. Just don’t rub it around the mouth. Grandma was stunned for a long time. She said that she had heard from parents with little differences that a swollen mouth was an allergy, and she thought her child would suffer from poor oral health for a lifetime.

To be honest, we sit down in the clinic one day and spend half the time being a "rumor crusher." After all, there are so many different opinions about food allergies now, and even the intervention ideas in the industry do not yet have completely unified standards. Most colleagues from the old school will recommend "strictly avoid it if you find it positive, and don't touch it at all." The advantage of this idea is that it is absolutely safe and will not trigger severe allergic reactions at all. It is suitable for high-risk patients with a history of anaphylactic shock and laryngeal edema. ； But the disadvantages are also obvious. After many people have strictly avoided it for a long time, their allergy thresholds have become lower and lower. It used to be that they would get a rash only after taking a big mouthful. Later, they would go to the emergency room if they got some dregs. Their quality of life was extremely poor, and children's growth and development were easily affected by lack of nutrition.

The idea of ​​oral immunotherapy that has emerged in recent years is different. Under the full supervision of doctors, exposure to allergens starts from low doses of a few milligrams or even micrograms, and the tolerance threshold is gradually raised. Many people persist for one or two years and can reach the level where they can eat normally without being allergic. I once had a 10-year-old patient who was severely allergic to wheat. He would gasp even after eating biscuits with wheat flour. He underwent immune induction for 18 months. During the follow-up visit last month, he held a meat bun and chewed it so deliciously that his mother stood beside him and almost shed tears. However, this plan is quite controversial. The risks are high. When we perform induction, we always have a full set of rescue equipment in the clinic, for fear of triggering severe allergies midway. ； Secondly, the scope of application is narrow, and patients with poorly controlled asthma or severe autoimmune diseases cannot do it. The academic community is still arguing about the specific indication boundaries, and no one dares to guarantee that it is suitable for everyone.

Another controversial point that has been quarreling for almost ten years is the "food intolerance test" sold by many medical examination institutions, which checks dozens or hundreds of food-specific IgG. If it is positive, people will avoid it. Some colleagues think that IgG is not an allergy indicator at all, but is just a sign that the body has been exposed to such food. Avoiding it will easily lead to nutritional imbalance. I once met a girl in her 20s who reported that she was positive for eggs, milk, wheat, and soybeans. After drinking white porridge for three months, she lost more than ten pounds and even had irregular menstruation. Finally, she did a food challenge test. Except for a slight rash after drinking milk, everything else was fine. However, some colleagues believe that for patients with long-term chronic diarrhea and unexplained rashes, temporarily avoiding high-IgG foods can indeed relieve symptoms and can be used as a reference for dietary adjustment. They cannot be killed with a stick. When we encounter patients with this kind of report, we usually ask about the specific symptoms first, and then make a comprehensive judgment based on the results of the IgE test and provocation test. We will never directly check the report and make a fasting list.

Don't tell me, in our line of work, we always carry a simulation of an epinephrine pen in the pocket of our white coat. When we meet a patient diagnosed with severe allergies for the first time, we have to teach him how to inject on the spot: prick the outside of the thigh, wait for 3 seconds before pulling out, rub for 10 seconds, and go to the hospital immediately after injecting. This is repeated several times, just to avoid being in a hurry when something really happens. When I meet parents who want to "test a small amount of food to train their children's immunity" at home, I have to repeatedly advise: Don't try it blindly. When we do induction, there are all rescue equipment around. If you trigger laryngeal edema at home, you can suppress it in a few minutes. It's really no joke.

In fact, after working in this field for almost ten years, the happiest thing is not that patients say "I can eat anything now", but that they no longer have to talk about "I am allergic" as a burden: children dare to attend their classmates' birthday parties, young people dare to go out for dinner with friends, and they don't have to look through the ingredient list for half an hour when ordering takeout. Of course, I have seen people who don't listen to advice. There was a college student who was allergic to peanuts. He thought he just had a rash and secretly ate peanut butter bread. As a result, he went into shock and was admitted to the ICU. After he was rescued, he never dared to touch it again. In the final analysis, we do not treat food as a scourge, we just want to help everyone find a safe distance from food.