Diagnosis
As a rule, the diagnosis of a house dust allergy can be made or quickly suspected when the above symptoms are described or visible. Furthermore, the patient survey is intended to clarify details such as the duration of the reaction, whether it was the first time an allergic reaction occurred, whether the allergic reaction was indoors or outdoors, whether other allergic diseases are already known, such as neurodermatitis or bronchial asthma. The background is that patients suffering from one of these diseases also have a high risk of suffering from a house dust allergy.
One calls these patients also Atopiker. Which kind of allergy is however present, is in most cases first not clear. All this applies to inquire, in order to be able to classify the kind of the allergy accordingly.
If the examination and the questioning do not bring any further indications, an allergy test should be carried out. In this test the body should come into contact with numerous substances and be provoked to develop an allergic reaction. For this purpose, the most common allergenic substances found in nature and in the household are prepared on an adhesive strip and applied to an area of skin, e.g. the back, etc.
of the patient. Here the adhesive strips remain stuck for a few days or until the patient expresses unbearable symptoms, such as severe itching. Then the adhesive strips are removed and the reactions that have been triggered are examined.
If redness or pustules have occurred, the patient is allergic to the antigen at this point. Furthermore, it is also possible to carry out a blood test on the patient. In this case, a complex procedure is used to determine above all the amount of the immunoglobulin IgE formed, which is particularly strongly formed in allergic reactions.
An attempt can also be made to detect increased histamine formation, which is also greatly increased in the case of a house dust allergy.
- If patients complain of shortness of breath, an anaphylactic reaction must be assumed, which can occur only once, e.g. after eating Chinese food etc.
- Depending on the time of year when the symptoms are indicated, hay fever must also always be assumed if the redness, itching and runny nose have started when staying outside.
- If redness is visible on one or more areas of the skin, it may also be an allergic reaction to a skin soap or lotion or newly applied detergent.
In order to confirm the presence of a house dust allergy, the so-called prick test is particularly useful. This can be carried out by an outpatient allergologist.
Here the allergen is applied to the skin. The skin in this area is then pricked a little with a small needle so that the substance can penetrate under the skin. After a few minutes, a check is then made to see whether the tested area shows any redness or swelling of the skin.
This indicates the presence of an allergic reaction to the applied substance. In addition, there is a blood test to detect special antibodies that can indicate the presence of a house dust allergy. This involves bringing the patient’s blood into contact with the allergen (e.g. mites or mite faeces).
If there are antibodies against these allergens in the blood, they bind. This binding can then be detected. The presence of antibodies against the allergens in the blood is equivalent to the presence of a house dust allergy.The rash with the house dust allergy presents itself with a symptomatology, which could apply in addition, to other allergies.
A hives fever develops on the skin. The nettle fever presents itself with two-dimensional wheals. These wheals are raised above the skin level due to the swelling and are reddish in color.
These wheals can also develop in contact allergies. In addition to the swelling, severe itching of the affected skin areas occurs. The location of the rash depends on which areas of skin have had contact with the house dust mites and especially their excrement.