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In the era of a pandemic, you postpone your visit to an allergist until tomorrow. This “tomorrow” has been running for 9 months and your health is at stake! Fortunately, the innovative solution, which is molecular diagnostics, allows us to reduce the number of visits to the office and laboratory …
A breakthrough in the diagnosis of allergies
The coronavirus has made other illnesses secondary, but they haven’t gone away. In the case of allergies, delay in diagnosis and delay in treatment may have serious consequences for our health, ranging from severe allergy to anaphylactic shock or attacks of bronchial asthma.
Unfortunately, the statistics are alarming – since March 2020 the number of specialist services has decreased by around 30%! What prevents us from visiting an allergist, on the one hand, is the fear of potential infection, and on the other hand, the difficult access to specialists.
Fortunately, the use of the latest allergy diagnostic strategy – inextricably linked with molecular diagnostics, significantly shortens the diagnostic path, accelerates the diagnosis of allergies and the initiation of treatment.
Molecular diagnosis of allergies
So far, in laboratory tests, checking the patient’s allergy to birch, we have determined the concentration of IgE antibodies in the blood serum to the mixture of proteins present in the birch tree. Such a mixture is called an allergen extract. On the other hand, molecular diagnostics of allergies is a test that allows to determine the concentration of antibodies to individual proteins that build, for example, birch allergen. These proteins are called allergen molecules and are responsible for causing specific allergic reactions.
Among the available tests using molecular diagnostics, we can distinguish tests that allow the determination of IgE antibodies against the extract and the most important molecules of one or two allergens, e.g. quantitative Polycheck tests and multiplex tests, e.g. Faber or ALEX2, allowing the determination of IgE antibodies against up to 295 extracts and allergen molecules.
Diagnosing allergies yesterday and today
In the traditional diagnostic model used so far, the physician, after conducting an interview, made a decision on the scope of additional tests to be performed and directed the patient, inter alia, to the lab. The skin and blood tests used, examining the reaction to whole allergen extracts, and not to individual allergen molecules, did not always allow to detect the cause of the allergy. In many cases, they did not provide complete information about the patient’s allergies. They caused a significant extension of the time from the first visit to a specialist to the development of recommendations and implementation of effective treatment.
It is not without reason that the new approach in diagnosing allergies, called the Bottom-up model among allergists, is “turning the diagnostic pyramid upside down”. In this case, we start the diagnostic path with a broad test, the result of which reflects the patient’s individual allergy profile.
The new strategy brings with it a number of benefits. Firstly, it allows to limit the number of patient-doctor-laboratory contacts, which in the face of the epidemic threat is of great importance. Secondly, multiplex molecular tests allow to characterize the entire repertoire of allergen-specific IgE antibodies for many potential allergens to which the patient is allergic, which significantly accelerates the correct diagnosis and optimization of therapy, including the decision to use allergen-specific immunotherapy, explains Professor Krzysztof Bułoczko.
Molecular tests have one more advantage – they allow to determine whether the patient must categorically avoid contact with a specific allergen source due to the high risk of a severe systemic reaction, or whether exposure to a given allergen will be associated only with the occurrence of mild symptoms.
For example, consider someone who is allergic to an apple with sudden swelling of their lips and throat. Molecular diagnostics will reveal whether it was a local, mild form of allergy to the main component of this fruit, i.e. Mal d 1, or the onset of life-threatening anaphylaxis, when in the ALEX test we obtain a positive result for Mal d 3 (or a thermostable lipid transport protein, similar to peach and nuts). Another example is milk allergy diagnosed by an IgE test with a mixture of many milk proteins. When it proves to be dependent on a component of Bos d 6 (bovine serum albumin) present only in raw milk, you can safely give your baby boiled milk and cheese. However, when ALEX shows allergy to Bos d 8 casein resistant to cooking temperature or digestive enzymes, it is necessary to use milk substitutes under the risk of shock – emphasizes prof. Krzysztof Buczyko.
Safety and precision in the diagnosis of allergies
Currently, there are two innovative multiplex tests available for molecular diagnosis of allergy: the FABER test and the ALEX 2 test. These are the latest generation tests based on nanotechnology. They enable testing of molecules and extracts at the same time, thanks to which they incomparably increase the diagnostic accuracy. Importantly, the patient does not have to stop taking medications (including antiallergic medications). To reach a milestone in the diagnosis of allergies, a prickle is all you need to do.
The FABER test introduced in 2016 allows the determination of IgE antibodies against 122 molecules and 122 allergen extracts from 123 different allergen sources (e.g. food, animals, plants). The FABER test was the first in one study to combine the advantages of traditional blood allergy tests (determination of IgE antibodies against allergen extracts) with the advantages of molecular diagnostics (determination of IgE antibodies against allergen molecules). What distinguishes the Faber test is the online platform to which both the doctor and the patient have access. It contains information about all the molecules and extracts that were positive in our study. In addition, this platform contains a description of protein groups that are important for a given patient and the routes of exposure to them. The patient also receives information about other allergens, in which there may be molecules that are potential sources of allergy as a result of cross-reactions.
In turn, the ALEX 2 study introduced in 2017. is the first test for the diagnosis of allergies with such a wide scope. It enables the simultaneous and quantitative measurement of the concentration of IgE antibodies against 295 parameters – 178 molecules and 117 allergen extracts, and total IgE. From one blood sample, we can determine whether a given patient is allergic to multiple or one allergen. It also allows you to obtain information on which group of proteins the molecules to which the patient is allergic belong. Thanks to this, the doctor can determine the risk of anaphylactic shock or introduce dietary recommendations that affect the patient’s quality of life. In case of positive results for molecules, the test result is automatically enriched with a short description of the groups of these proteins.