Severe and persistent allergic rhino-conjunctivitis is usually triggered by exposure to common environmental tree and grass pollens (pollinosis).
The World Health Organization divides allergic rhinitis (AR) into intermittent (less than four days per week or less than four weeks duration) and persistent (more than four days per week and over four weeks in duration). Intermittent and persistent AR are further sub-divided into mild (minimal symptoms) or moderate/ severe (troublesome symptoms, sleep disturbance and impairment of daily activities).
Hay fever symptoms
Symptoms such as intense itching of the nose, eyes, palate, ears and throat with repetitive bouts of sneezing, profuse watery nose and tearing occur when pollen levels exceed 30 grains per cubic metre of air (grains/m3). Pollen levels may rise above 500 grains/m3 at the peak of the grass pollen season. Occasionally, pollen triggered wheezing may occur in the form of allergic asthma or ‘hay asthma’. The trigger allergens start with tree pollen (Cypress, Oak, Plane, Acacia and Olive) in early spring (August), followed by a long-grass pollen ‘surge’ (Bermuda, Lolium, Rye and Eragrostis) persisting from September to the end of February.
Weed pollens (English plantain and Cosmos) rise for a short period in late summer and fungal or mould spores (Alternaria, Cladosporium and Epicoccum) predominate in damp spring and autumn but tend to be less problematic than pollen grains, unless spore counts exceed 3000 per cubic metre.
In South Africa, we rarely see the Silver Birch tree pollen oral allergy cross-reactions which occurs when eating certain fresh stone-fruits such as apples, pears, cherries and hazelnuts (oral allergy syndrome), as is so often seen in Western Europe.
Treatment for severe symptoms
‘Steroidophobia’, the fear of using cortisone sprays, is a major stumbling block to treatment with nasal steroids and patients need a careful explanation as to how important continued low dose nasal application is to continued symptom control. Steroid side effects such as growth retardation, cataracts and osteopaenia do not occur at the recommended dosages, but concomitant inhaled steroid use for asthma should be borne in mind when assessing the overall ‘steroid load’.
A short course of oral steroids, perhaps 20mg prednisone daily for five days will usually unblock even the most resistant nose and give good symptom relief whilst the antihistamines and regular inhaled steroids get to work. This is particularly useful at exam time or for special events such as weddings. However, repeat long-lasting steroid injections, although very effective, should be discouraged for fear of causing unpredictable side effects (osteoporosis, high blood pressure, diabetes) and local muscle thinning and atrophy. Commencing regular antihistamine medication up to four weeks before the pollen season has been shown to significantly improve symptom control in severe hay fever.
Source: Dr Adrian Morris Allergy Clinic. www.allergyclinic.co.za/hay-fever
