Pollen allergy in children

Pollen (a fine powder from grasses, trees, weeds, and flowers) is an example of an allergen. Asthma is the most common chronic lung disease in childhood – most of these children are also suffering from co-existing hay fever, with pollen being the most important allergen.

By Dr Pieter J de Waal, Paediatrician and Allergologist, MediClinic, Bloemfontein

Compared to adults, children spend more time outside and on grass layered sport fields. It is therefore not surprising that they are more vulnerable to environmental pollen allergies. The current, devastating effect of global warming has noticeably increased atmospheric pollen counts worldwide and has a dramatic negative effect on allergy sufferers, with poor asthma and hay fever control direct consequences.

Windy days and thunderstorms are well known facilitators of pollen transmission and increase atmospheric pollen counts dramatically, making these conditions more favourable for pollen allergy symptom flares.

Causes and symptoms

Pollen gets into the body by either inhaling it into the lungs or direct deposition of pollen particles inside the nasal passages. In susceptible people, the immune system “sees” these particles as foreign (strange) and launches an attack against it by producing an antibody, called IgE. When this antibody binds to certain cells of the immune system, it causes the release of many allergy promoting chemicals, both locally in the nose and systemically in the bloodstream – the most important chemical is called histamine. Genetic susceptibility (having a first degree allergic relative, say mother and/or father) is still the biggest predictor of pollen allergy in a child.

Asthma and hay fever commonly starts in childhood. Asthma is a condition where the airways become chronically inflamed, causing it to become “twitchy”. This results in uncontrolled contraction and eventually thickening of the muscles around the smaller airpipes within the lungs.

The airway closes and fresh, oxygen rich air cannot be inhaled into the lungs, making it very difficult for the asthmatic to breath. Pollens are important triggers of this. Coughing, shortness of breath, activity (exercise) intolerance and chest wheezing, are common symptoms of asthma.

Symptoms of hay fever symptoms may vary from mild to severe and can affect a patient’s daily quality of life substantially. A chronically blocked nose may affect a child quality of sleep, leading to poor rest at night, waking up feeling tired, poor concentration at school and even poor academic performance.

When to see a doctor

If your child is suffering from any of the symptoms above, irrespective of severity, seek medical attention immediately. Asthma symptoms may vary from a mild, chronic cough to a life threatening, sudden, unpredictable closure of the airways, called an acute asthma attack. Uncontrolled hay fever may lead to uncontrolled asthma, so leaving it untreated, can be devastating.

Treatment

Identification of the specific pollen your child is allergic to, is of utmost importance. This can be done by skin prick testing. During this procedure, droplets of different allergens are placed on the skin, followed by a small prick.

Alternatively, when a skin prick test is not available, a blood test can be performed. This will identify the IgE antibody against a specific pollen. Once this has been done, specific pollen avoidance is easier. Strategies to avoid pollen exposure include: • avoid going out on windy days and thunderstorms • avoid freshly mown grass • consider planting a low allergen garden around the house • close all ventilation openings and windows of the car, especially when travelling – pollen entering the car from outside, may lead to high pollen exposure in a confined space for prolonged periods

Once your child is diagnosed with asthma and/or hay fever, the daily use of medicine is important. It is impossible to avoid pollen exposure completely, so pro-actively treating these conditions, and keeping symptoms under control, rather than waiting for a sudden asthma or hay fever attack cannot be emphasised enough.

Asthma is treated with daily, safe antiinflammatory inhaled therapy (also called asthma pumps). Hay fever is treated with a combination of an anti-inflammatory nasal spray and antihistamine medication.

It should be noted that pollen allergy is a chronic condition – your child should take the medication every day, in the right way. Ask your doctor to explain the correct technique of using an asthma pump and nasal spray, otherwise it will be ineffective.

Immunotherapy against pollen is currently the only potentially curative treatment for pollen allergy. After pollen avoidance strategies and medicines are proven to be ineffective, immunotherapy against pollen can be considered.

This includes monthly injections under the skin (in your doctor’s office), or daily medicine placed under the togue (at home), to gradually “train” your immune system to get use to pollen. Immunotherapy is typically performed for a minimum period of three years (sometimes longer).

Pollen calendars

After identifying the pollen to which your child reacts, you may visit the South African pollen count website (www.pollencount.co.za). Here you can track the atmospheric counts of different pollens in most major cities in South Africa. This will assist you to be extra vigilant during your child’s “problematic” weeks and pro-actively treat symptoms when they start occurring. 

For more information on this topic and other allergies, patients are encouraged to visit the Allergy Foundation of South Africa’s website at www.allergyfoundation.co.za