Allergic Conjunctivitis and Nasal Allergy

Abstract

Allergic conjunctivitis (AC) can be divided into the primary form (caused by an allergic reaction occurring primarily in the conjunctivae) and the secondary form (induced by allergic reaction originating primarily in the nasal mucosa, where the released mediators can reach conjunctiva through the lacrimal system, the blood, the lymphatic network, or the neurogenic network). Patients with primary AC develop an immediate, late, or delayed conjunctival response (CR) during conjunctival provocation tests. Patients with secondary AC develop an immediate, late, or delayed type of secondary CR, induced by the nasal allergic reaction, due to the nasal allergen challenge. Various hypersensitivity mechanisms may be involved in the particular CR types. The secondarily induced AC and CRs can only be confirmed by nasal provocations tests, performed by rhinomanometry combined with recording of conjunctival signs. The existence of the primary and secondarily induced AC has an impact on treatment of this disorder.

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

“…In these 61 patients, 94 NPTs with inhalant allergens (Supplementary Table 2S), with respect to the positive skin tests and/or suspect disease history, and 61 phosphate-buffered saline (PBS) control tests were performed by means of rhinomanometry [7][8][9][10]26,29,30 combined with the recording of ocular signs and symptoms. [7][8][9][10]26,27 The patients were investigated in a period without acute ocular and nasal complaints and outside the allergen-relevant season.…”

“…[7][8][9][10]26,27 The patients were investigated in a period without acute ocular and nasal complaints and outside the allergen-relevant season. Long-acting H1-receptor antagonists and topical glucocorticosteroids were withdrawn 6 weeks before, whereas other treatments 48 h before each of the NPTs.…”

“…These parameters were evaluated by means of the modified Pelikan's grading system (Supplementary Table 1S). [8][9][10]26,27 Collection and processing of tears…”

“…The secondary keratoconjunctivitis form is induced by the allergic reaction taking place in the nasal mucosa due to the exposure of nasal mucosa to an inhalant allergen. [7][8][9][10] Various hypersensitivity mechanisms, such as immediate (IgE-mediated) type, late type (type III), or delayed type (cell-mediated), can underlie the primary as well as the secondary form of keratoconjunctivitis, which may then result in the development of three basic keratoconjunctival response types, an immediate, a late, or a delayed type. There is a dearth of data demonstrating the role of a nasal allergy in the conjunctiva, cornea and in the possible induction of the secondary keratoconjunctival response (SKCR).…”

“…[7][8][9][10]16,23,26 Moreover, little data are available to illustrate the cytologic changes in tears during the particular types of SKCR. [7][8][9][10] The purpose of this study, which is a continuation of our earlier work, [7][8][9][10]27 was (1) to investigate the cytologic profiles and changes in the counts of individual cell lineages in tears during the particular types of SKCR, (2) to evaluate the significance of cytologic changes in tears for the possible role of various immunologic mechanism(s) underlying the particular types of SKCR.…”