food allergy complaints

There is no need to make a conclusion in advance that "I am allergic to a certain food" based on the time interval between suspicious food intake and the onset of the attack, the specific symptoms at the time of the attack, the history of similar symptoms in the past, and whether you have been exposed to other factors that may induce allergies in the same period.

Last week, when I was doing my internship at the allergy clinic, I met a 16-year-old girl who came in with her face covered. The first thing she said when she entered the door was, "Doctor, I'm allergic to milk tea. Please give me some allergy medicine." Her face was so swollen that there was only a slit left for her eyes. It was really uncomfortable to look at. The teacher was not in a hurry to prescribe medicine, but asked a few questions first: When did you drink the milk tea? Did you eat anything else between the time you drank it and when you had the attack? The little girl hesitated and said that she drank the milk tea after school in the afternoon the day before. In the evening, she went to a seafood buffet with her friends and ate half a plate of arctic clams. She felt her face was itchy after eating just before going to bed.

Later, the serum specific IgE was checked, and it turned out that she was allergic to Arctic Berry's tropomyosin, and it had nothing to do with the milk tea. If she bites her to death, it is the milk tea, and the real cause will most likely be missed, and she will have to step into the trap next time she eats seafood. Many people assume that allergies cause rashes and shortness of breath within a few minutes to half an hour after eating. In fact, clinically, delayed allergies account for more than 30%. Last month, I met a brother in his 40s who developed purpura on both lower limbs for a week. I went to several departments but couldn't find the cause. Then I came to our department. After questioning for a long time, I remembered that my colleague gave him half a pack of salt-baked cashews three days before the onset of the disease. He had never eaten cashews before. After checking the IgG, it turned out that it was a delayed-type hypersensitivity reaction mediated by cashews.

At this point, I would also like to mention the current controversy in the academic community: the traditional mainstream view of allergology is that only IgE-mediated immediate reactions belong to the category of classic food allergy. Only IgE test results need to be provided in the chief complaint, and IgG has little reference value.； However, many scholars in the clinical immunology department have suggested that many recurrent chronic urticaria and allergic purpura are related to IgG-mediated delayed allergy. If patients have relevant test reports, they can also bring them with them for reference to the doctor. There is no need to rule them out completely.

Our department teachers often tell patients who come to see us that if they really can’t remember what they ate, they should list everything they consumed in the 72 hours before the onset of the disease, including the granules they drank, the gum they chewed, and even the crushed nut condiments sprinkled in takeaways. Many people are allergic to invisible ingredients. A college student once said that he was allergic to salad, but after a lot of searches, it turned out that it was chopped peanuts added to the salad dressing. He himself was severely allergic to peanuts, and when he ordered, he didn't notice that the merchant added it by default.

There is also the kind of cross-allergy that is so deeply hidden that many people never even think of mentioning it when they complain. For example, people who are allergic to Artemisia pollen may experience perioral itching when eating peaches, apples, and cherries in autumn. The scientific name is pollen-food allergy syndrome. I once had an aunt who suffered from allergic rhinitis every autumn, and her mouth would swell when she ate peaches. She always thought she was allergic to peaches. Later, after getting pricked, she found out that it was a cross-reaction of Artemisia pollen. Eating peaches in spring will not cause any problems. Only eating during the autumn pollen season will cause reactions.

In fact, to put it bluntly, the chief complaint is the first piece of the puzzle you hand to the doctor. You don’t have to put it together in advance to make up for it in your mind. Just hand over all the pieces in your hand intact. Don’t pick and choose only what you think is right. Instead, you may easily spell the wrong answer. After all, allergies are a complicated matter. If you give more clues, you can always find the root cause.