The causes of mite allergy lie in an excessive response of the immune system. In addition to the physical symptoms, allergies often also affect the psychological aspect of the child, which is why it is essential to learn how to manage it
Leonardo is 9 years old and has been fighting a cold that never seems to go away, red eyes and a constantly running nose. After various attempts and medical visits, allergy tests gave a name to his disorder: allergy to dust mites. Mom and dad, like many families in this situation, ask themselves: «What can we do now? What therapies are available? And above all: will it be possible to improve your quality of life?
Beyond the physical symptoms, dust mite allergy often also affects the psychological aspect: sleeping poorly due to nasal congestion, having constantly red eyes or not being able to concentrate at school due to itching and coughing can become frustrating and affect the child’s mood and social relationships. This is why it is important to understand this condition thoroughly and intervene with targeted management.
What is dust mite allergy
«Dust mites, what exactly are they? There is a difference between dust allergy and mite allergy.” Let’s clarify things a little. We often speak generically of “dust allergy”, when in reality the main problem is not the dust itself, but the mites that nest inside it. These are small organisms invisible to the naked eye, similar to tiny spiders, that live in domestic environments. Talking about the difference between dust allergy and mite allergy is therefore fundamental: while dust can contain various allergens (pollen, mould, animal hair), mites represent a very specific cause of allergic reactions.
Dust mites: characteristics and diffusion
In more detail, dust mites are microorganisms belonging to the arachnid family, which feed on fragments of human and animal skin. The main species of mites responsible for allergies are Dermatophagoides pteronyssinus And Dermatophagoides farinae. Both produce highly sensitizing allergenic proteins, but have some differences:
- Dermatophagoides pteronyssinus is more widespread in humid and coastal areas. It prefers environments with high relative humidity (60–80%) and is particularly present in mattresses and pillows.
- Dermatophagoides farinae, on the other hand, is more adaptable and is also found in drier and more continental areas. It is common in carpets and in the dust of floors and upholstered furniture.
The relative distribution of the two species therefore varies depending on the climate and housing conditions, but in many countries (including Italy) they coexist and contribute together to the onset of symptoms.
Habitats and environments favorable to mites are therefore warm and humid places, with the presence of fabrics, pillows, duvets, curtains and soft toys. It is no coincidence that the bedroom is the main “reservoir” of mites in homes.
Causes and mechanism of allergy
The causes of mite allergy lie in an excessive response of the immune system. In predisposed subjects, immune cells produce antibodies of the IgE class, which recognize harmless elements coming from mites as dangerous. The main allergens are the proteins contained in feces and fragments of the dead body of mites, which are easily inhaled because they mix with house dust. In particular, two major allergens (Der p 1 and Der p 2 for Dermatophagoides pteronyssinus and Der f 1 and Der f 2 for Dermatophagoides farinae) have a strong sensitizing power. The mechanism is this: upon first contact the immune system “trains” by producing specific IgE; on subsequent contacts, when the allergen is inhaled, IgE binds to mast cells and releases substances such as histamine, causing sneezing, congestion, itching or bronchospasm.
Dust mite allergies: symptoms
Symptoms can affect different areas and vary in intensity:
- Cough: persistent, dry, more intense at night or upon waking.
- Ocular symptoms: red, swollen eyes, with strong tearing and itching.
- Bronchospasm and asthma: Chronic exposure can worsen existing asthma or make it appear, with wheezing and shortness of breath.
- Dermatitis: the skin can react with eczema, especially in children predisposed to atopy.
- Diffuse itching: less frequent, but possible, especially in those with skin manifestations.
An important aspect is that the symptoms are more persistent than those caused by pollen (which follow seasonality), because exposure to mites is continuous throughout the year. This can have a significant psychological impact, especially in children: sleeping poorly, having red eyes and chronic breathing difficulties can generate irritability, difficulty concentrating and discomfort in social relationships.
Worst periods of mite allergy
Mite allergy does not have a clear seasonality, but some periods can be more critical. In autumn and winter, with windows closed and heating on, the concentration of allergens increases. Furthermore, the higher humidity of some homes in this season favors the survival of mites. In spring-summer, however, ventilation and exposure to the sun reduce their density. However, symptoms can still persist in more sensitive individuals.
Allergy diagnosis
«Are there any tests for dust allergy?». The diagnosis of mite allergy is based first and foremost on clinical evaluation: the accurate collection of the child’s history (symptoms, seasonality, environmental conditions) is the first fundamental step. Often it is the clinic itself that guides the specialist and distinguishes allergy from other forms of chronic rhinitis or recurrent infections.
Laboratory instruments then serve to confirm the hypothesis:
- Skin prick test. It is a minimally invasive test, which consists of penetrating very small quantities of allergen through the skin (usually on the forearm) with a light prick. If the child is sensitized, a small red wheal appears within a few minutes.
- Specific IgE measurement. It requires a blood sample and allows you to measure the presence of antibodies directed against mite allergens.
These tests, interpreted together with the clinical picture, allow the specialist to arrive at a correct diagnosis and to plan the most appropriate therapy.
Allergy to mites: the remedies
The treatment of mite allergy is not based on a single strategy, but on multiple levels that must be integrated. Let’s see them in detail.
Environmental prophylaxis: the first fundamental step
Reducing exposure to mites is the most important measure, because it acts directly on the cause. It is impossible to eliminate them completely, but some practical rules can significantly reduce their presence:
- wash sheets and blankets at temperatures ≥ 60 °C;
- use anti-mite covers and linens for mattresses and pillows;
- ventilate the rooms regularly, keeping the humidity below 50%;
- eliminate carpets, heavy curtains and soft toys, or at least wash them often;
- prefer washable floors and vacuum cleaners with HEPA filters.
These measures, although requiring consistency, are those that most impact the quality of life of allergic children.
Drug therapy: to control symptoms
When prophylaxis alone is not enough, the doctor can prescribe medications for mite allergy as support. That is to say:
- antihistamines for sneezing, itching and conjunctivitis;
- cortisone nasal sprays in case of persistent congestion;
- bronchodilators or inhaled cortisone in children with asthma.
Medicines do not cure the cause, but reduce the symptoms and should always be taken under medical supervision.
Immunotherapy (the so-called “vaccine”)
It is the only treatment capable of modifying the natural history of the disease, progressively reducing sensitization. It is offered when prophylaxis and medications are not sufficient or when symptoms are severe and persistent. It can be administered sublingually or subcutaneously and typically lasts 3–5 years.
Mite allergy: potentially dangerous foods
In some subjects, a phenomenon of cross allergy to mites occurs: proteins similar to those of mites are also found in crustaceans and molluscs. This means that some mite allergy sufferers may have reactions to eating shrimp, lobsters, mussels and snails. This does not mean that people with mite allergies must necessarily avoid these foods, but it is an aspect to keep in mind and discuss with the doctor, especially in children with asthma and severe allergies.
Mite allergy and vaccines
Specific immunotherapy, also known as “allergy vaccine”, represents the only intervention capable of modifying the natural evolution of mite allergy, gradually reducing the sensitization of the immune system.
It is indicated in children with persistent and significant symptoms, when environmental prophylactic measures and drugs are not sufficient to guarantee effective control of the disease. Immunotherapy can lead to lasting reduction in symptoms, decrease the risk of developing asthma, and limit the need for long-term medications.
However, there are some contraindications: it is not recommended in cases of immune pathologies, during pregnancy or in subjects taking beta blockers, as these conditions can increase the risk of adverse reactions. The decision to start treatment must always be made together with the specialist, carefully evaluating the benefits and risks based on the child’s clinical picture.
Practical advice
The management of mite allergy requires an integrated approach, with attention to environmental prophylaxis as a first step. Airing rooms, keeping humidity low, washing sheets and blankets at high temperatures and using anti-mite covers helps significantly reduce symptoms.
Clinical monitoring is also important: regular consultations with an allergist and dermatologist, when necessary at the discretion of the pediatrician, allow the drug therapy to be adapted and the need for immunotherapy to be assessed. Medicines and treatments must always be followed according to medical indications.
In summary, combining environmental prophylaxis, targeted therapy and pediatric monitoring is the most effective way to improve the quality of life of allergic children.
