Quand pratiquer un bilan allergologique en pathologie oculaire ?

Abstract

Ocular allergy can take several different clinical forms, including those in which IgE-mediated reactions are predominant or in others where they are an aggregating factor. The need for an allergy workup varies depending on the clinical manifestations. Pollen-induced conjunctivitis, so-called seasonal pollinosis, is in general easily diagnosed and the allergy workup is used only to confirm the identity of the responsible allergen(s). Conjunctivitis associated with perennial allergens is sometimes more difficult to diagnose, in which case the allergy workup is a essential diagnostic element. However, allergic sensitisation is not always synonymous with allergic conjunctivitis, and other local examinations, such as a conjunctival provocation test, are sometimes necessary to establish the diagnosis. Atopic vernal keratoconjunctivitis and atopic keratoconjunctivitis are two special forms of keratoconjunctivitis, the first involving pre-pubertal males and the second involving young adults with a history of atopic dermatitis. In these two conditions, conjunctival sensitisation is not the principal mechanism, but it can aggravate the disease. Results of an allergy workup can provide evidence for recommending avoidance of the allergen(s) or specific immunotherapy, which may ameliorate the evolution of the disease. Contact eczema may require a dermatological workup when the allergen has not been identified in the allergy workup. Finally, certain cases of chronic conjunctivitis occurring in association with dry eye syndrome or with blepharitis, such as ocular rosacea, can look like allergic conjunctivitis and vice versa. An allergy workup is then an important diagnostic element. Thus, an allergy workup has a variable but often important place in the care of patients with conjunctivitis.