Wednesday July 11, 2012
Early detection of allergy
An expert guide on allergy detection.
ALLERGY is best nipped in the bud because if it is not detected early and managed well, it will progress from one form, say, eczema to another, such as asthma, later on in the child’s life. This is called the Allergy March.
About 60% of all allergies appear during the first year of life. And children from allergy-free families still harbour a 15% risk of developing allergy.
Here, Dr Amir H.A. Latiff, a consultant paediatrician and clinical immunologist and allergist, and the president of the Malaysian Society of Allergy and Immunology, guides parents on allergy detection:
Why is early allergy detection important for a child?
It enables the child to be given the correct and optimal treatment. This includes determining and then avoiding the allergens or substances that are causing the allergy, rather than guessing the wrong ones. Hence, the allergy becomes better controlled, resulting in improved quality of life for the child and family.
How can we know if a child is allergic? Does an allergic child possess certain “giveaway” features?
Allergy presents itself in many ways. It particularly affects the skin, airways (nose and lungs), eyes, gastrointestinal system and the cardiovascular system (causing low blood pressure and shock in life-threatening allergic reactions known as anaphylaxis).
A family history of allergy (e.g. parents or siblings) would strongly suggest that a child is at risk. Typically, allergy symptoms are persistent and occur almost daily for at least an hour.
Examples of nasal allergy symptoms include runny nose (both nostrils), violent repetitive sneezing, blocked or itchy nose, which may be accompanied by red, itchy, and watery eyes. When the nose, or both the nose and eyes are involved, the allergy is known as allergic rhinitis or rhino-conjunctivitis, respectively.
Allergic asthma may appear as a chronic cough (especially at night), with wheezing and shortness of breath. Other typical allergy symptoms are hives, eczema and swelling (angioedema). When swelling occurs internally and involves the throat, it may lead to choking.
Allergic diseases have a peculiarity whereby at different ages, the child suffers different forms of allergy. This is the Allergy March, where the child “grows out” of one allergic disease (e.g. eczema), only to start another form (e.g. allergic asthma).
When should a child be taken to see an allergist? And what information would the allergist need from the parents to help him in his diagnosis?
Various types of information can help in early identification of children at risk of allergy. For example, sensitisation to hen’s egg and dust mites during the first year of life, long-lasting sensitisation to certain offending foods during the first two years of life and atopic dermatitis in early infancy are predictors of allergic sensitisations and/or allergic airway diseases later on in childhood.
Once allergy is suspected, an allergist/immunologist should be consulted. Generally, the allergist would want to know the symptoms and then establish a consistent and significant relationship between the symptoms and exposure of the child to possible allergens.
What are the methods commonly used in allergy detection for children?
The allergist needs to study the child’s allergy history to find out whether it really points to allergy. If yes, further tests are done to pinpoint the allergens, either through blood or skin prick tests, which detect the presence of specific IgE antibodies. Both tests require expert interpretation by a clinician specialising in allergy or immunology.
What are the possible consequences if an allergy goes undetected in a child?
Undetected allergic diseases in a child would result in:
> A delay in investigation leading to a correct diagnosis.
> A delay in giving the child optimal treatment.
> A delay in preventing the progression of allergic diseases (Allergy March).
> Increased sensitisation towards the allergens.
The above will then worsen the allergic diseases and increase the risk of fatality. It is important to recognise as distinctly as possible, the features which distinguish a fatality-prone child, for example, a food-allergic child.
Early detection of allergy improves the quality of life for the child besides reducing unnecessary stress for the whole family.
Article courtesy of the Malaysian Society of Allergy and Immunology (MSAI). For more details or information on allergy, visit allergymsai.org or xyzofallergy.org. MSAI was officially launched in 1998 to provide better patient care and quality of life to the sufferers of allergic diseases and their families. Since then, the society has been actively involved in disseminating information on immune-mediated diseases, particularly allergy and primary immunodeficiency diseases to healthcare professionals and the public. It also keeps abreast of new knowledge and findings in all aspects of basic sciences and treatment of these diseases at regional and international levels.