[Conjunctival provocation test: recommendations].
The diagnosis of ocular allergy, which has become a real public health problem occurring in 25% of the general population and continues to rise, requires allergic testing. Skin and blood tests combined with interviewing the patient demonstrate sensitivity to one or more antigens. However, while allergic testing and interviews generally reveal the cause of the symptoms, only the conjunctival provocation test (CPT) provides clear evidence of a functional relation between the conjunctival pathology and exposure to the antigen. Since there is still no validated consensus regarding the criteria for positivity of the CPT in routine practice, the working group attempted to establish the major guidelines for conducting the test, to standardize approaches and pinpoint areas of uncertainty. The group established a consensus regarding the conditions for using the test (patient selection, allergens to be tested, usable concentrations, the test protocol, the signs and symptoms to be assessed, interpretation of results, follow-up) and identified two distinct patient groups (outpatients and hospitalized patients) in whom test-taking conditions are different. The outpatient group includes patients suffering from benign forms of conjunctivitis (acute, seasonal, or chronic) and those sensitive to the usual allergens (mainly domestic and airborne). In these cases, the test is given in a medical setting with an allergologist or an ophthalmologist who instills the drops relatively rapidly. The criterion for positivity is the extent of the pruritus. On the other hand, in the hospital population, which is composed of patients suffering from vernal conjunctivitis, the attempt to establish the triggering factor requires a more elaborate protocol carried out in an ophthalmologic setting and based on the association of a range of clinical and biological factors. The deliberations of the working group should lead to the standardization of the CPT procedure for diagnostic purposes.