Provocation tests with allergens

Nasal Provocation Test in the Diagnosis of Allergic Rhinitis

“…Indeed, the specific NPT is the method of choice for the reproducibility of the allergic reaction, and it is indicated when discrepancies arise in the assessment of a patient's medical history and the results of skin and/or serological tests, as reviewed by several authors (Litvyakova LI & Baraniuk JN. 2001;Loureiro, 2001;Dordal et al, 2011;Mellilo, 1997;Naclerio & Norman, 1998 …”

“…The first allergen challenge was performed in 1873, by Blackley, who elicited a nasal response after an application of fresh pollen to the membrane of his own nostrils (Blackley, 1873). After this first NPT, several consensus and guidelines have been published trying to achieve a better diagnostic approach of allergic disease and its knowledge (Dordal et al, 2011;Druce & Schumacher, 1990;Gosepath et al, 2005;Litvyakova & Baraniuk, 2001Lund et al, 1994;Malm et al, 2000;Mellilo et al, 1997;Schumacher, 1992).…”

“…Supported by the concept of the bidirectional "unified airway" respiratory inflammation, a local provocation test is useful in the diagnosis of allergic respiratory disease. Concerning these aspects, the NPT is the method of choice for the reproducibility of the allergic reaction (Litvyakova & Baraniuk, 2001;Loureiro, 2001;Mellilo, 1997;Naclerio & Norman, 1998). Thus the NPT may be considered a model of respiratory provocation test, easy to perform, in the demonstration of the immediate and late phase of type I hypersensitivity reaction.…”

Cellular changes in tears associated with keratoconjunctival responses induced by nasal allergy

“…These tests, performed on a certain organ, may definitely (1) confirm the existence of an allergic component in the particular and/or related organ(s); (2) demonstrate that a certain allergen causes indeed a certain response type in the particular organ, which can be measured quantitatively in its dynamic course; (3) to confirm the causal role of an allergic reaction occurring initially in one organ, in the secondarily induced response of another organ 7,9,10,26,[38][39][40][41] The conjunctival provocation tests with allergens are a suitable technique to demonstrate the primary conjunctival/keratoconjunctival responses resulting from direct exposure of the ocular tissue to an external allergen. 4,11,16,17,20,25,33,35,36,38,[42][43][44] However, they are unable to detect conjunctival/keratoconjunctival responses induced secondarily by an allergic reaction occurring initially in the nasal mucosa. These responses can only be detected by the NPT with allergens, in combination with registration of ocular features.…”

“…[7][8][9][10]16,23,26 However, the involvement of the individual cell types in the allergic reaction can only be evaluated by comparing their counts and their conditions before and repeatedly after a well-defined intervention, which is an allergen challenge. [7][8][9][10]12,14,16,26,27,34,35,38 Keratoconjunctival response-cytologic changes in tears Z Pelikan…”