Dust mites surround us. Burrowing cheerfully into our pillowcases, rugs and furniture, the mites feast on our dead skin cells, breaking them down into small particles they can digest.
Now that your skin is crawling, relax. If you’re like most people, you will never know they are there.
An unlucky minority, however, is very aware of dust mites. Some of these unfortunate folks have a simple dust allergy. But others have an additional condition called atopic dermatitis, often referred to as eczema. They react to the presence of dust — or rather, dust mites — with itching and redness.
It wasn’t evident exactly what caused people with eczema and dermatitis to react so badly to dust mites. According to a new study in The Journal of Investigative Dermatology, the bodies and excrement of dust mites are embedded with allergens that can worsen a variety of skin conditions such as eczema, dermatitis, and psoriasis.
What is a dust mite allergy?
Dust mite allergy is a hypersensitive (IgE mediated) reaction to proteins in the excrement of dust mites. These proteins can cause an allergic reaction in the respiratory passages causing the symptoms of hay fever and asthma. It can often aggravate atopic dermatitis (eczema) in people who have this problem, including causing facial eczema that can be difficult to treat.
House dust mites are found in all homes. They are microscopic organisms that thrive in warm and humid houses with lots of food – human and animal skin and mould spores. The mites prefer to live in beds, which contain lots of moisture from our breath and bodies, plus the shed skin cells which they eat. As we spend about a third of the day in bed, we all inhale large quantities of dust mite allergens.
A dust mite allergy does not refer to an allergy to dust alone. It includes an allergic reaction to the dust mite particles and waste; it is the dust mite debris that causes the allergy to develop. While a dust mite is extremely small, so small that it can only be viewed under a microscope, it can produce nearly 200 times its own weight in faecal matter. It is the proteins in the waste that act as allergens.
Signs of symptoms of dust mites
People react to dust mites differently depending on their tolerance to bites and strength of their immune systems. Rashes caused can start out as small macular spots and later progress into larger, intensely itchy, dry patches that might “erupt” as they heal.
Symptoms of a dust mite allergy include:
- Hay fever like symptoms: runny nose, itching, sneezing.
- Watering itchy eyes.
- Eczema (inflammatory skin disease) may get worse.
- Swollen eyes and difficulty sleeping
If a dust mite allergy persists and triggers asthma, a person may also experience:
- Tightness or pain in the chest
- Trouble breathing
- Shortness of breath and coughing that interferes with sleep
If you believe you or your child is suffering from dust mite allergies, see a doctor to evaluate the situation. An allergist can determine the cause of your symptoms and come up with a plan to control your allergy symptoms. On your initial visit the allergist will likely ask you many questions to determine when your allergies seem to flare up. In addition to a physical exam and medical history, your allergist will probably perform a few diagnostic procedures, including:
A skin allergy test
A skin allergy test will be conducted to determine what you are allergic too. During this test, the allergist will take purified allergen proteins and needle them into your skin’s surface. After the droplets are left on for 15 minutes, the allergist will observe your skin for any allergic reactions. If you are allergic to any of the substances, your skin will likely be red, swollen or itchy in that area.
In cases where skin allergy tests cannot be conducted due to certain skin problems or medical conditions, a blood test will be done. With a blood test, your allergist will be able to determine how sensitive you are to any given allergen and to check for the presence of antibodies that would cause allergic reactions to any allergens.