Accurate Allergy Testing Through the MAST Test

Hello.

This is Mutuel Plastic Surgery Clinic.

When allergy testing comes up, one of the questions patients ask most often is, “Can a single blood test tell us everything?”

In reality, it is less of a “complete answer” and more of a “screening test that can provide many clues at once.”

MAST (Multiple Allergen Simultaneous Test) is an abbreviation for Multiple Allergen Simultaneous Test. It is a test designed to measure allergen-related antibodies in the blood, called specific IgE (sIgE), for multiple antigens at the same time.

Because one blood draw can reveal the possible responses to dozens of antigens, including respiratory, food, animal, and insect allergens, it is very useful as a way to quickly narrow down the possibilities when it is hard to determine exactly what someone has been exposed to.

Today, for those who are hearing about the MAST test for the first time or are still unfamiliar with it, Mutuel will explain in detail from the basic principles to key points in interpreting the results, as well as how it differs from single tests.

How does the test work?

The basic principle is to check whether there is IgE in the blood that binds to specific antigens.

There are several laboratory methods, but representative forms include immunoblot methods and automated tests based on chemiluminescence.

Each method differs slightly in sensitivity, specificity, and measurement range, but they all provide the common information that if sIgE is detected, the person may have been sensitized to that antigen.

The important point is that “sensitization” and “clinical hypersensitivity (actual allergy symptoms)” are different, and a positive test result does not necessarily mean that allergy symptoms will occur.

Therefore, test results must be interpreted together with the medical history (symptoms and exposure situation) in order to make a more accurate diagnosis.

In what situations is it performed?

MAST is used for allergy testing in a variety of situations.

The most common case is when symptoms are present but it is difficult to identify the antigen, such as with itching, hives, or rhinitis.

It is also used for patients with skin conditions or those taking antihistamines, or when a skin test cannot be done right away.

In addition, it is useful as a screening tool when you want to narrow down the candidates more quickly among many antigens, and especially in children or in situations where a patient's consent for testing is difficult, the ability to check multiple antigens with one blood test is a very major advantage.

What is the difference from a single test?

In direct comparisons, skin prick testing (SPT) generally shows better predictive value (sensitivity/specificity), and some studies have reported that the concordance between MAST and SPT results is limited.

In other words, the two are not completely interchangeable.

MAST is an allergy test that has the advantage of being relatively convenient because it can check many antigens simultaneously with just a blood draw, but it provides different information from SPT, which captures the physiological sensitivity of skin reactions.

If necessary, a quantitative test for a single antigen, such as ImmunoCAP, can be used to check the specific antigen (sIgE concentration) more precisely, and clinical decisions must be made by combining test results with the patient's symptoms, exposure history, and sometimes additional tests. Because this is necessary for accurate diagnosis, clear evaluation by a dermatologist is important in this process.

How is it performed?

No special additional preparation is needed, and it is performed the same way as a standard blood draw.

In particular, antihistamines can affect skin testing, but blood tests such as MAST are convenient because there is no need to stop medication.

However, there may be exceptions depending on the medications being taken or the immune status, so we recommend discussing this with the doctor in charge.

The time required varies by laboratory, but results are usually available within a few days to one week.

When you receive the test report, you can see the positive antigens and the strength of the reaction.

A stronger reaction does not always mean more severe clinical symptoms, so how the result is interpreted is very important.

Before a skin procedure, how should allergy checks be done?

At Mutuel, we sometimes receive requests for allergy testing before skin procedures such as fillers or lasers.

In these cases, MAST is useful for quickly screening many antigens, and when it is difficult to identify a clear allergy through history alone, it can definitely help confirm an overall allergic tendency.

However, allergies to specific procedure materials (such as filler or anesthetic ingredients) may not be included by default in the MAST panel,

so for patients with a history of a specific allergy to a drug or material related to the procedure, separate serum tests or skin tests for that substance should be considered.

Establishing a safe plan based on these test results is the best way to ensure the best outcome.

In closing...

The MAST test, which is widely used in clinical practice, is a very useful tool because it allows screening of many antigens at once.

However, test results should always be interpreted comprehensively by considering the patient's clinical symptoms and exposure history, and if necessary, confirmation through additional tests such as skin tests, quantitative single-antigen tests, or challenge tests is the most accurate approach.

Even before various procedures or dermatology treatment, these tests can be very helpful for accurate and safe care, so it is good to keep them in mind.

We also recommend that you always ask the medical staff which antigens are included in the panel and how the test results should be interpreted before testing.

At Mutuel, we always keep in mind that tests are only a tool, and that customized interpretation centered on symptoms is the starting point for accurate treatment.

If you have any additional questions, please visit our clinic for a consultation. We will always do our best to provide kind, personalized care tailored to each person's concerns.

This has been Mutuel Plastic Surgery Clinic.

Thank you.