Eosinophil cationic protein in tears of normal subjects and patients affected by vernal keratoconjunctivitis

Abstract

The objectives of this study were to determine: 1) levels of tear eosinophil cationic protein (ECP) in patients with vernal keratoconjunctivitis (VKC); 2) the effect of pharmacologic therapy on ECP release; and 3) the correlation of this mediator with the severity of the disease. Tears were collected from 10 controls and 20 VKC patients before and after therapy for cytologic analysis and ECP measurement by radioimmunoassay. Ocular signs and symptoms were evaluated before tear collection. Mean ECP levels in controls were 7.5 ± 0.4 μg/l, and in VKC patients, 988.3 ± 128 μg/l before therapy (PPPP<0.001), and the number of eosinophils in tears (P<0.005). The results of this study suggest that tear ECP levels accurately reflect the clinical status of VKC patients. The measurement of ECP may prove useful not only in the diagnosis and monitoring of allergic disease, but also as an objective parameter for the evaluation of new antiallergic therapies.