Cross allergy – causes, symptoms & therapy

One speaks of a cross-allergy when a person reacts allergically to several substances at the same time. This is due to allergens that are contained in a wide variety of natural raw materials and cause cross-allergy.

The affected patients then suffer, for example, from a birch pollen allergy and are also allergic to apples because both substances contain the same molecules. The allergic reaction that the body shows can be more severe in a cross-allergy than in a normal individual allergy.

causes

The cause of the cross-allergy is the very similar protein structure of some allergens. The human body does not distinguish whether the allergen is originally contained in a pollen or a fruit. A cross-allergy is particularly common in patients who are allergic to birch, hazel or alder pollen .More than half of these people have a cross-allergy to nuts and certain fruits that belong to the rose family. These include almonds, cherries, apples, pears, plums and peaches. Mugwort pollen allergy sufferers are even worse affected by the cross-allergy. Most often they suffer from allergic reactions to celery plants. In many cases, they also have a cross-allergy to spices and vegetables such as parsley or carrots.

Certain herbs such as thyme or basil can also trigger a cross-allergy in them. In addition to pollen allergy sufferers, people with an allergy to house dust or fish are more likely to have a cross-allergy. People who are allergic to fish sometimes do not tolerate chicken eggs. In the case of mite sensitivity, the cross-allergy occasionally occurs when seafood is eaten.

symptoms and course

Typical symptoms of cross allergy:

• shortness of breath

• skin rash

• itching

• Diarrhea

In the case of a cross-allergy, the mucous membrane in the mouth reddens after eating food. If the reaction is more severe, the mucous membrane also swells. In severe cases, this can lead to those affected complaining of shortness of breath or being threatened with suffocation. Another typical symptom is a rash, which is accompanied by severe itching. In the case of a pollen allergy, the mucous membranes of the eyes and nose react.

The result is hay fever or conjunctivitis . Diarrhea accompanies the cross-allergy more rarely. The most extreme physical reaction to a cross-allergy is immune shock, which can be life-threatening.

Diagnose

To diagnose a cross-allergy, a dermatologist performs a conventional allergy test on the patient. If the patient decides to have a patch test, he wears a patch on his upper arm or on his back for three days. The doctor previously soaked the plaster with various allergens. If the doctor removes the patch and discovers reddened areas, the patient is allergic.

Based on the exact locations of the redness , the dermatologist can determine which substance is causing the allergy. In the so-called skin prick test, on the other hand, the dermatologist slightly scratches the patient ‘s skin . He puts a drop of an allergen on this open spot. In this case, too, the skin reddens if the person is allergic. The advantage of this method is that it gives a result within a few minutes. Regardless of the procedure used, the dermatologist will also test whether there is a cross-allergy.

complications

Various complications are possible as a result of a cross-allergy. In extreme cases, they can take on serious proportions. In principle, the allergic reaction in a cross-allergy proceeds in exactly the same way as in a conventional allergy. For this reason, similarly serious consequences are conceivable with this form of allergy as with the other forms. The nature and extent of the symptoms vary from person to person. For example, in the case of a cross allergy from food allergy and pollen allergy, symptoms can occur in the gastrointestinal region as well as in the mouth and throat. The foods in question have similar structures to the triggering original allergen.

One possible consequence of the cross allergy is shortness of breath. It is caused either by the original allergy itself or by the cross-allergy. The allergic reaction causes swelling of the mucous membranes in the bronchi, trachea and larynx. As these areas narrow, airflow is obstructed. This, in turn, causes breathing problems.

One of the most serious complications of cross-allergy is the dreaded anaphylactic shock , also known as allergic shock. In some people, this even assumes life-threatening proportions because the patient’s blood circulation is dramatically impaired. In some cases, there is even a risk of cardiac arrest with fatal consequences. Allergic shock is a medical emergency that requires immediate resuscitation of the patient or treatment by an ambulance.

treatment and therapy

A cross-allergy can be treated with medication and by a so-called hyposensitization. During hyposensitization, the doctor injects a minimal dose of the allergen under the patient’s skin. He takes into account the different variants of the substance that trigger the cross-allergy.

Treatment usually lasts three to five years. However, the doctor can only carry it out if the patient tolerates the low-dose allergen. If this is the case, he increases the amount of substance administered in each session. A significant improvement in the situation can be achieved after just one year. When treatment is complete, full recovery is possible in many patients.Medicines are given to people who cannot carry out this treatment method because of allergic reactions. If you have a rash, your doctor will prescribe ointments that contain cortisone . In the case of hay fever and other allergic reactions that affect the mucous membranes and conjunctiva, the family doctor uses antihistamines .

The active ingredients it contains block the body’s own substance histamine , which plays an important role in cross-allergy. Patients who show an extreme allergic reaction are given an emergency kit by the doctor, the medicines in which help with an immune shock caused by a cross-allergy.

prevention

A cross-allergy can only be prevented to a limited extent. Pollen allergy sufferers would have to stay at home during the pollen flight. That might not be a solution for most people. The best way to prevent it is to eat food.