Definition
A house dust allergy is an allergic reaction of the body to the finest dust particles, which occur in the household and seasonally limited or all year round. A house dust allergy would correctly have to be called “house dust mite allergy“. The allergen, i.e. the substance causing the allergy, is namely the excrement of the house dust mite. House dust mites are primarily found in human dwellings, and survival outdoors is hardly possible.
Causes and forms
There are two different forms that lead to a house dust allergy:
- Dust particles: Dust particles are partly visible, partly they cannot be seen by the human eye. Thousands of them are in the air all the time, in closed, mainly living rooms. The air pollution of these particles is drastically increased when the apartment is cleaned and there is a whirling up of dust particles that have been lying on smooth surfaces or in upholstery.
These smallest dust particles are inhaled unconsciously with every breath and can either cause immediate discomfort or only lead to an allergic reaction after chronic inhalation.
- House dust mites: They are about 0.1 mm in size and are found mainly in upholstered furniture, beds or carpets. Their size makes them invisible to the human eye. Over time, the mites accumulate in the bed and in upholstered furniture.
Especially with old upholstery, the proportion of mites can be greatly increased. The mites’ excrement is light and can get into the ambient air. There it is swirled around and there is a danger of inhaling it. Similar to house dust, this can lead to corresponding allergic reactions and complaints.
Reactions of the body
There are numerous reactions of the body to penetrated particles and foreign bodies in house dust allergy. One of them is the formation of so-called immunoglobulins. These are called IgE in the allergic reaction caused by house dust.
When dust particles penetrate through the airways, the body produces numerous IgE. These bind to so-called mast cells. If house dust particles or mites penetrate again, a mast cell-IgE complex approaches and binds to this foreign body.
The aim of this maneuver is to bind the intruder and render it harmless. However, what happens additionally is the formation and emission of histamine. This is a substance that can trigger numerous reactions in the body, including the contraction of the bronchi.
This leads to the classic breathing difficulties described in allergic reactions. Furthermore, histamine causes blood vessels to dilate, which results in an increased flow of blood. This then leads to the classic redness in the area of the skin or in the conjunctiva of the eyes.
Furthermore, histamine also leads to a swelling of the mucous membranes and to an increased production of the body’s own mucus and secretion. As a result, allergy sufferers suffer from a runny nose, rhinitis and watery eyes in an allergic reaction. Initially, patients can be completely free of symptoms if they come into contact with mites or house dust.
However, as soon as the above-described immune defence has developed, the body can respond quickly to newly intruded allergens. In more harmless cases, these consist of watery eyes and a runny nose. Stronger immune reactions can also lead to reddening of the skin.
These can be localized and only occur in certain parts of the body or can be visible all over the body (in the case of particularly severe allergic reactions). A corresponding release of histamine leads to a narrowing of the airways. However, this reaction only occurs in the case of very strong allergic reactions.
Initially, only slight coughing and itching as well as scratching of the throat occur. In addition to a strong reddening of the eyes, swelling of the eyelids may also occur. The eyes themselves are usually sensitive and itchy in an allergic reaction.
Foreign bodies such as contact lenses are not tolerated. In the case of very strong reactions, the bronchial tubes can become narrow with accompanying shortness of breath. In this case, a quick reaction is required to avert this life-threatening condition.
The full picture of these symptoms is also called an anaphylactic reaction. A life-threatening condition resulting from this is also called anaphylactic shock.Furthermore, allergic reactions of this kind can also be accompanied by a deterioration of the general condition. The patients are often weakened, unable to cope with stress and tired.
Furthermore, longer-lasting allergic reactions, such as prolonged skin itching etc., can also have a negative effect on the psychological situation. The stronger the allergic reactions, the more restless the patients become. Patients often panic, especially when ventilation is restricted due to a narrowing of the bronchial tubes.
Find out more at:
- Cough in case of allergy
- You can recognize a mite allergy by these symptoms
A house dust allergy can manifest itself on the skin through redness, swelling and rashes. Itching can also occur. Itching, watery eyes, increased coughing and sneezing and a runny nose are also common.
