Table of Contents
WHAT IS CROSS REACTIVITY?
Cross-reactivity occurs when your body’s immune system mistakenly determines that the proteins of one substance and the proteins of another are similar.
The direct response of the immune system to an allergen – a specific type of protein
Hello,
The life of people with allergies is not easy. Instead of walking to see the beautiful spring flowers, they could not breathe, instead of enjoying the culinary pleasure, they were afraid and did not dare to taste the strange foods. There are a lot of animals that they love so much, but unfortunately they cannot be with them.
Their allergic reactions like this have been clarified by me in my previous conversations about different types of allergies, such as wheat allergy, general food allergy, pollen allergy, and latex allergy.
All of these allergies, regardless of the cause of any food, pollen or latex, all have the same principle that the body’s immune system has wrongly determined that the substance is food allergens, pollen or latex which are harmful and react to excessively.
The most common of these allergies is that the immune system produces an antibody called IgE, which is specific to contacting or ingesting the proteins, pollen or latex of a food at the first moment of its life. Then the next time they are exposed or ingested to food, pollen, or pus, the specific IgE antibody-forming reactions mentioned above, along with a host of other toxic chemicals, disrupt a wide range of functions of the organ systems of the body, which are accompanied by the typical symptoms of food allergies or latex allergy.
Again, food allergies can be caused by the most common foods which are milk, eggs, wheat, soybeans, peanuts, tree nuts, fish, and shellfish.
Pollen allergies, also known as allergic rhinitis, or also very special names – hay fever, can be caused by pollen plants usually in spring, grass pollen usually in spring and summer, the Weed pollen is common in the fall, fungal spores and mold are common in the warmer months, and can be caused by dogs, cats, rabbits, etc. in all seasons of the year.
And latex allergy, directly caused by latex from trees containing latex, most of course, from rubber trees and white latex trees like figs, banyan, banyan, plantain, cactus, oleander, etc. indirectly through household products, toys or tools, medical or health care supplies that contain or contain natural latex ingredients.
The cross-reactivity of the immune system to a protein similar in structure to that of the protein has been “recalled”.
But in practice, allergy phenomena occur even more complicated because not only because allergies occur to specific proteins, identified as just above, but also some other proteins are structurally similar to these proteins, in another food. As a result, the immune system is so sensitive that it is similar and produces allergic reactions known as “cross reactivity”. This is especially the case when a new protein received by the body is structurally at least 70% homologous to a protein pre-reacted by the immune system. Well, if the similarity is less than 70%, then cross-reactivity is unlikely.
In fact, cross-reactivity can occur from one food to another; between pollen and food; and, between latex and food, etc.
So now, as you can imagine that this cross-reactivity is the second wrong reaction of the immune system to a homologous protein (for example, a protein from a fruit) after making the first mistake for the protein to which it is allergic (for example, latex protein from a rubber tree)
Due to cross-reactivity, testing and diagnosing food allergies can be difficult. Because the immune system recognizes proteins that are structurally similar to a type. While a blood test (i.e. a serum IgE test) or a subcutaneous injection may be positive for a food or pollen, the person may actually be cross-allergic to another substance. Therefore, these test results may not correctly identify the true food allergen, in fact leading to many cases where, even though they test positive for a food, they still eat without experiencing anything, and vice versa, there is. also foods that can cause crossbreeding. reactivity, the tests mentioned above may not detect it.
CROSS-REACTIVITY RATE IN THE POPULATION
- About 70% of people with food allergies also suffer from other allergies, including pollen allergies.
- About 20% of the population has a pollen allergy, about half of them also suffer from oral allergy, also known as oral allergy syndrome, or hypersensitivity to foods; and a few of them also had intestinal allergies.
- There is no less than 30% of all cases of latex allergy, or latex allergy to a food allergy. And most non-food allergies can be accompanied by oral or gastrointestinal reactions.
- There are at least 30% of children with atopic dermatitis – eczema also has food allergies, mainly to cow’s milk, eggs, peanuts, etc.
- And cross-reactivity between crustaceans and mites is also quite common etc …
SOME SPECIFIC TYPES OF CROSS-REACTIVITY
Here are some more specific types of cross-reactivity to consider:
– Cross-reactivity between cow’s milk and that of other mammals such as goats and sheep
For a person allergic to cow’s milk, their risk of allergy to goat’s or sheep’s milk can be up to 90%.
However, if a person is allergic to mare’s milk or donkey’s milk, the risk of a cross-reaction with cow’s milk is only about 5%.
– Cross-reactivity between foods in the same group of animals
Fortunately, this type of cross allergy is rare. For example, most people with allergies to cow’s milk can still eat beef, and most people with allergies to eggs will continue to eat chicken as usual.
– Cross reaction between peanuts and other beans such as soybeans, lentils, etc.
Can people with peanut allergies eat soy or other beans? This is a frequently asked question, but it is not easy to answer briefly with “yes" or “no” as in fact more than 50% of patients are allergic to peanuts, although the results are also positive for soy or another bean, but up to 95% of them are still able to eat those beans. So, although according to the statistical results of many cases, there are many people who are allergic to peanuts but can still eat another type of bean, but for each individual and if you are also allergic to peanuts. Peanuts, you should only eat certain types of beans that you are sure will not cause you problems.
– Cross reaction between peanuts with nuts or seeds.
It is very clear that peanuts are legumes and are definitely different from nuts such as almonds, walnuts or cashews etc.
However, up to 35% of toddlers in North America with a peanut allergy are also allergic to tree nuts. In addition, it is not easy for children to distinguish peanuts from other nuts. Therefore, doctors recommend that young children with peanut allergies avoid tree nuts.
– The same goes for peanut allergies and allergies to nuts like sesame seeds.
There are cases of allergies to peanuts and sesame seeds, which is more likely due to their allergies to both than to a cross allergy.
– The most common cross reaction of a fruit allergy is between peaches and watermelon.
And, for tree nuts, the possibility of cross-reactivity between cashews and pistachios or between walnuts and pecans is very likely.
Please note that a person with a single nut allergy does not necessarily mean an allergy to all nuts. In other words, even though they may be allergic to this nut, they can still eat other nuts as normal.
– Cross reactivity between fish species.
In fact, there are so many cross-reactions between different species of fish, both freshwater and saltwater, that it’s hard to list them all. Once a person has an allergy to one fish, the risk of allergy to another fish can be as high as 50%. And, as a tip, if you have a fish allergy, it’s best to avoid all types of fish if there is cross-reactivity.
– Cross-reactivity between shellfish.
Shellfish, fish, peanuts and tree nuts are often associated with serious, potentially fatal reactions.
In addition, there is an additional threat is the high risk of cross-reactivity between crustaceans (crustaceans like shrimp species like lobster, tiger shrimp, crab etc …), with a risk ratio of up to 75%.
For cross reactivity between crustaceans and non-crustaceans (such as mollusks such as clams, clams, snails, mussels, squid, octopus, etc.) the risk ratio is present; may be lower at the above rate.
Notably, there have also been cases of cross-reactivity between chitinous crustaceans (such as grasshoppers) and crustaceans. This is also the reason why “false positive” test results for shellfish show no clinical symptoms.
– Cross reaction between pollen and food
(Also known as pollen-food syndrome or oral allergic syndrome – OSA)
Some people who are allergic to pollen (i.e., allergic rhinitis or hay fever) may develop symptoms around the mouth, in the mouth and in the throat immediately after eating foods such as certain vegetables, fresh fruits or certain types of seeds, containing a protein that cross-reacts with pollen.
In fact, many people experience pollen cross-reactivity with the following foods:
• Birch pollen: with raw apples, peaches, plums, apricots, mangoes, carrots, peanuts and hazelnuts, etc.
• Houndstooth pollen: with bananas, melons, peaches;
• Grass pollen: watermelon, cucumber, banana, sunflower;
• Absinthe pollen: with carrot, celery, peach;
• Yes, timothy grass pollen: with apple, lychee, tomato, celery, corn, pepper, paprika.
• etc.
Most people with a pollen allergy, or hay fever, cross-react with two or more foods. The most common symptoms are itching, swelling and itching in the mouth or on the lips and about 10% have gastrointestinal symptoms.
The symptoms of cross-reactivity are also varied here. A slight tingling may also be on the lips, tongue, palate and throat. More serious may include hives around the mouth or swelling of the lips, a feeling of tightness in the tongue and throat. And the most dangerous, in about 3% of cases, is that in addition to the swelling and itching in the mouth or throat as above, it can occur all over the body and about 10% have intestinal symptoms. And the worst is always the situations that lead to anaphylaxis.
Note, for some foods with pollen cross-reactivity, their cooked form can be tolerated without causing allergy. The reason is that these cross reactive proteins are broken down at high temperatures, for example raw apples can cause allergies, but apple pie is safe.
On the contrary, there are many varieties, whether ripe or raw, unlikely to cause allergies, such as peanuts and tree nuts.
On the other hand, the cross-reactivity of food allergy to pollen may only increase during the pollination season but decrease thereafter. Therefore, some foods cause allergies during the pollination season but are then eaten again.
And not all people with pollen allergies suffer from mouth allergy syndrome (OAS) like this. In contrast, people with mouth allergy syndrome may experience symptoms of pollen cross-reactivity with just a few foods, but not all.
– Cross-reaction between latex and food
Latex is a natural product derived from latex. Popular natural latex products include rubber gloves and balloons. Latex can cause some sort of allergic reaction or at least the irritant contact dermatitis that I talked about in a previous talk.
In addition, in addition to the allergic reactions that occur directly due to such a latex protein agent, there are also about 30-50% cases of cross-reactivity when encountering other fruits, the most common of which are are banana, avocado, chestnut, apple, kiwi, potato, tomato, watermelon, papaya. The reason is that in the human body with latex allergy, there are specific IgE antibodies against the latex proteins, when the body comes into contact with and absorbs other proteins in the food eaten but has a similar structure with latex proteins, an immediate allergic reaction occurs. Although the symptoms of greatest concern are hives, swelling, wheezing, and especially anaphylaxis, fortunately, the overall incidence of IgE-mediated reactions to latex is relatively rare. And most of the reactions reported are sensitive to exposure.
PREVENT AND TREAT CROSS-REACTIVITY:
Avoid allergens
The prevention and treatment of cross-reactivity as well as for allergies in general should follow the basic principle: avoid allergens, which means avoiding contact and absorption of products or foods containing allergens.
However, in order to do that, you need to get tested to find out what you are allergic to and then remove them from the menu or avoid exposure.
Using anti-allergic drugs
Especially for cases of pollen allergy, this is really difficult as the pollen can overwhelm the habitat of the flowering season and it is difficult to avoid breathing and exposure to pollen if it is not possible not to go out. In this case, you may need to use antiallergic drugs. Examples include cromoglycate, ketotifen, and a combination of antihistamines and probiotics, etc.
Fortunately, the latest generations of antihistamines are available today which work very well in suppressing the symptoms of allergies with little harm to the body.
In the event of a severe allergic reaction, you can use an emergency treatment needle (eg Epipen ™) if you are well informed about its use.
In many approaches and research into the treatment of allergies, immunological research has also made great strides. Immunotherapy can be carried out for the patient by applying a minimal dose of the allergen to cause mild allergies to the body and then gradually increasing the tolerance and adaptation of the body to the allergen, which causes and then reduces the real allergy for the patient.
I wish you good health, goodbye and see you soon!
