Allergic rhinoconjunctivitis

The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee. Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema ISAAC. Lancet 1998 351 1225-1232. 

Cromolyn and nedocromil solutions are also useful in reducing symptoms of allergic rhinoconjunctivitis. Applying the solution by nasal spray or eye drops several times a day is effective in about 75% of patients, even during the peak pollen season. 

Vourdas D, Syrigou E, Potamianou P, Carat F, Batard T, Andre C, Papageorgiou PS Double-blind, placebo-controlled evaluation of sublingual immunotherapy with standardized olive pollen extract in pediatric patients with allergic rhinoconjunctivitis and mild asthma due to olive pollen sensitization. Allergy 1998 53 662-672. 

La Rosa M, Ranno C, Andri C, Carat F, Tosca MA, Canonica GW Double-blind placebo-controlled evaluation of sublingual-swallow immunotherapy with standardized Parietaria judaica extract in children with allergic rhinoconjunctivitis. J Allergy Clin Immunol 1999 104 ... 

Khinchi MS, Poulsen LK, Carat F, Andre C, Mailing HJ Clinical efficacy of sublingual-swallow and subcutaneous immunotherapy in patients with allergic rhinoconjunctivitis due to birch pollen. A double-blind, double-dummy placebo-controlled study. Allergy 2000 54(suppl 63) 24. 

Wessner DB, Wessner S, Mohrenschlager M, Rakoski J, Ring J Efficacy and safety of sublingual immunotherapy in adults with allergic rhinoconjunctivitis Results after 2 years of a controlled trial (abstract). Allergy 2001 56(suppl 68) 88. 

Atopy denotes a hereditary predisposition for IgE-mediated allergic reactions. Clinical pictures include allergic rhinoconjunctivitis ( hay fever ), bronchial asthma, atopic dermatitis (neurodermatitis, atopic eczema) and urticaria. Evidently, differentiation ofT-helper (TH) lymphocytes toward the TH2 phenotype is the common denominator. Therapeutic interventions are aimed at different levels to influence pathophysiological events (A). 

Oral antihistamines may be used to alleviate symptoms of allergic rhinoconjunctivitis. These include over-the-counter first-generation antihistamines such as chlorpheniramine maleate (Chlor-Trimeton) and diphenhydramine hydrochloride (Benadryl). Second-generation less sedating antihistamines include fexofenadine hydrochloride (Allegra), loratadine (Claritin), deslorata-dine (Clarinex), and cetirizine hydrochloride (Zyrtec). Dry eye symptoms may be an adverse reaction to oral antihistamines, including second generation. 

However, Pearce et al. [14(NC)] have written that the problem of information bias is of particular concern in asthma epidemiology issues because of the difficulties in defining and measuring asthma, allergic rhinoconjunctivitis and atopic eczema, and the difficulties in obtaining exposure information in the aetiologically relevant time period. However, provided that the information has been collected in a standardized manner, then misclassification will be non-differential, and any bias it produces will usually be towards the null value. 

Although, asthma, allergic rhinoconjunctivitis and eczema are related, ISAAC showed that most symptomatic children had symptoms of only one disorder in the previous year, rather than two or three. Observations like this indicate that factors required for the clinical expression of each of these disorders may differ in timing or effect [6(III)]. 

---