Detection of Eosinophil in Patient with Allergic Conjunctivitis by Impression Cytology

ABSTRACT

Allergic conjunctivitis is commonly encountered in the office parctice of ophthalmology. However, diagnosis is not easy because allergic conjunctivitis shows nonspecific ocular symptoms and signs. And for accurate diagnosis, conjunctival scraping for eosinophils, tear levels of specific IgE, skin testing to aeroallergens, and ocular challenge with allergens are available but these methods are much time and cost consuming. So we evaluate the usefulness of the detection of eosinophils by conjunctival impression cytology. Conjunctival impression cytology was done on 44 eyes of 44 patients who were diagnosed as allergic conjunctivitis. 7 eyes of 7 normal subjects and 14 eyes of 14 patients with epidemic keratoconjunctivits were used as control. Scoring system was defined according to the past history, symptom, sign, and slit lamp finding ranged from +1 to +5. Eyes of score +1 or +2 were defined as allergy suspect group, and eyes of score +3 to +5 defined as allergy group. The sensitivities of the impression dytology were 59% in allergy suspect group, 86% in definite allergy group and 72%in total, The specificity was 95%. According this study, we conclude that impression cytology is a simple, non-invasive and cheap method with high sensitivity and specificity for the diagnosis of allergic conjunctivitis.