Tests of allergy to the consulting room of the doctor

Tests of allergy to the consulting room of the doctor
These methods profit from a real passion since about fifteen years. Their harmlessness, the speed of the answers which they bring, the possibility of multiplying them, make an invaluable auxiliary of the diagnosis of it allergologic.

For what are used they?
The tests have as an interest to simulate in a visible way, on the skin, the conflict generated by allergic sensitizing inside the organization.

The tests come following the clinical survey carried out by the expert. So sometimes the diagnostic orientation is evoked by the simple private clinic: typical hay cold, asthma with the hairs of animals or the acarina, urticaria food or medicamentous, in many cases several factors intriquent and complicate the step. More and more often, the doctors are in front of this type of situation and must refine their diagnosis.

Technique of the tests
The tests most usually applied to the cabinet of the expert are the épidermiques stamps (patch-tests) and tests (prick-tests).

Stamps

They are used for the research of the allergies of contact like for that of certain food allergies. They consist of the application of a series of stamps coated with the substance which one suspects being responsible for the allergy to different concentrations, or of several substances tested at the same time. These stamps are stuck on the skin of the patient and are left in place a few hours or a few days. The goal is to obtain a local effect similar to the symptom dominating of the patient.

A very great number of professional eczemas find their explanation thus. Potassium bichromate of cements (masons), solvents and dyes chemical (various industries), materials as various as of the shampoos or lacquers (hairdressers) paintings (body), etc the allergy to latex, rare but very handicapping, is thus easily highlighted.

The child can profit from this technique as of more the young age, for eczemas of contact: products of toilet, detergents and softeners, soaps but also in the event of food eczema of origin. A certain number of aggressive agents are thus uncovered: milk, certainly, but also the egg white, certain vegetables, of the food dyes. The increasing complexity of certain food like the exotic mixtures of fruits, the introduction of dyes, fixers, gelling and others makes often delicate this type of diagnosis. Can one think that the introduction into the genetically modified protein organization will contribute to thicken even certain mysteries?

Épidermiques tests

The épidermiques tests consist in introducing the allergens by a tiny puncture of less than one millimetre of depth. The reaction awaited in the minutes which follow is a more or less broad papule resembling a puncture of nettle.

It is there too the field of the food allergies at the origin of crises of urticaria and especially that of the respiratory problems like asthma and the seasonal rhinitis due to pollens. The studied agents are very numerous, to start with ten families of acarina. Then come dust from house, bakery, of wood or cereals, the many atmospheric moulds, pollens and the hairs of animals, the chemical food and derivatives.

The diagnosis of allergy was largely facilitated by the development of the batteries of test cutaneous. All these tests can be refined by a blood control. Certain allergens should be required besides only by one blood test and of the reactions observed in laboratory. It is the case of drugs: antibiotics, aspirine for the principal ones. It is also the case of venoms of hyménoptères.