Dust mite allergy is a common allergy triggered by dust mites present in the home. The allergy can cause severe reactions in people of any age.
The symptoms observed in the case of a dust mite allergy include:
Allergic rhinitis or runny nose
Allergic conjunctivitis or watering, red, itchy eyes
Exacerbation of asthma causing wheezing, breathing difficulty and chest tightness
Skin irritation with itchy rashes forming blisters that may ooze fluids
The dust mite
House dust mites are tiny creatures invisible to the naked eye and requiring a microscope to view. The mites are present in almost all homes and feed on shed skin cells. Dust mites tend to be located in dark, damp and warm areas including mattresses, carpets, soft toys, clothes, pillows and cushions. They are harmless to most people but cause symptoms in those with an allergy to them.
Allergic reactions to the mites occur on inhalation of the allergens present in microscopic droppings from the mites which float in the air.
In susceptible individuals, prevention of contact with the dust mites is one of the best ways to minimize reactions. Although complete removal of the dust mites from homes may not be possible, their numbers may be significantly reduced and this can help to alleviate symptoms.
Steps to remove or reduce dust mites from homes include removing damp areas, improving ventilation (especially in bedrooms and living rooms), preventing the build up of dust through regular cleaning and airing of bed linen, mattresses, pillows and carpets. Ornaments, objects and surfaces can also be wiped with a damp rather than dry cloth to prevent dust gathering in the air. All clothes, soft toys and bed linen should be washed at temperatures over 60Â°C to kill the dust mites.
Diagnosis and treatment
Diagnosis of dust mite allergy is based on a detailed history of allergic symptoms and how they manifest on exposure to dust. A skin prick test may be performed to confirm the allergy in individuals who have more than one allergy.
When an allergic reaction occurs, it can be treated with long acting non-seditative antihistamines such as levocetirizine, loratadine and azelastine. People who develop asthma as a symptom may benefit from long-term use of montelukast, a leukotriene receptor antagonist.
Reviewed by Sally Robertson, BSc