Explainer: All You Need to Know about Allergic Rhinitis

By: Dr Magdy Badran , Consultant Ped Immunology

CAIRO, Nov. 17 (SEE)- Rhinitis is defined as inflammation of the nasal mucus membrane, it can be pided broadly into two major categories : allergic and nonallergic .

Allergic rhinitis ( AR ) is a very common chronic disorder, its prevalence is 20%. It is often ignored, misdiagnosed and its importance as a cause of morbidity is underestimated.

The prevalence in the industrialized world is increasing, particularly in urban areas. Exposure to high levels of pollutants including oxides of nitrogen, sulfur dioxide, black smoke, large particulate matter, small particulates, carbon monoxide, and volatile organic compounds have been considered as important contributing factors in both exacerbation and etiology of allergic airway diseases . Global climate change is evidenced by elevated pollen levels and increase of air pollutants as carbon dioxide, ozone, and nitrous oxide. Worsened air quality enhances the allergic responses and increases prevalence of AR.

AR causes symptoms such as stuffy nose , sneezing, runny nose, watery eyes and itching of the nose, eyes or the roof of the mouth. Other symptoms can also occur, such as coughing, wheezing, and headache .

Generally, AR develops before the age of 20 years in 80% of cases. Children in families with a bilateral family history of allergy generally develop symptoms before puberty and those with a unilateral family history tend to develop their symptoms later in life or not at all. Studies in children in the first years of life have shown that the risk of AR was higher in those with early introduction of foods or formula, heavy maternal cigarette smoking in the first year of life, exposure to indoor allergens such as house dust mite and parental allergic disorders.

The allergy can be seasonal or perennial. Symptoms of seasonal AR occur in spring, summer and/or early fall. They are usually caused by allergic sensitivity to pollen from trees, grasses or weeds, or to airborne mold spores.

Perennial AR appears year-round , it is most common in people with allergies to allergens that are present all year.It is generally caused by sensitivity to house dust mites, animal dander, cockroaches and/or mold spores. Sensitization to outdoor allergens e.g. pollen occurs when the child is 3-5 years and to indoor allergens e.g. house dust mites at an earlier age.

Both AR and sinusitis are linked to each other, because AR causes the nose to become blocked and in turn blocks the sinuses. Some prefer the term "rhinosinusitis" to the separate terms "rhinitis" and "sinusitis." This is because the nose and sinus mucosa are contiguous, rhinitis and sinusitis frequently occur together and rhinitis commonly leads to sinusitis.

If uncontrolled or inappropriately treated, AR can severely impair quality of life for children and their families. It has a serious impact on the children's health, well being , concentration ,learning, school performance and quality of life .It can result in significant sleep disturbance and fatigue .

Untreated AR can impair driving ability and put patients at risk. Drug therapy reduces this impairment, and AR patients should therefore be advised to always treat their condition.

Common complications include sinusitis, bronchial asthma, otitis media, nasal polyps and obstructive sleep apnea. AR is present in 75% of children with bronchial asthma .

The best way to prevent AR is to avoid the allergen. This may mean changing your habits, or even giving away a pet or moving to another house if the symptoms are unbearable and don't respond to medications.

Other prevention methods include: removing furniture that collects dust (e.g., carpets, draperies, and stuffed chairs), washing floors frequently with a wet mop and staying indoors during dust storms and high pollen times.

Once diagnosed, AR treatment options are: avoidance, eliminating or decreasing your exposure to the irritants or allergens that trigger your symptoms, medication and allergen immunotherapy . Allergen immunotherapy in children and young adults can reduce the likelihood of the development of asthma in patients with only AR.