Topical 0.1% Prednisolone Lowers Nerve Growth Factor Expression in Keratoconjunctivitis Sicca Patients

Purpose: To compare nerve growth factor (NGF) levels in tears and on the ocular surface of normal controls with those of non-Sjogren type keratoconjunctivitis sicca (KCS) subjects, and investigate the effect of 0.1% prednisolone eye drops on NGF levels in KCS patients. Methods: Baseline tear NGF levels were measured in 41 KCS patients and 23 healthy control subjects using enzyme-linked immunosorbent assays (ELISA). KCS patients received 0.1% prednisolone drops in one eye, and 0.1% hyaluronic acid drops in the other eye, three times daily for 28 days. Impression cytology (IC) and immunostaining for NGF on conjunctival epithelium was performed for both groups. Results: KCS patients were found to have higher baseline tear NGF concentrations compared to age-and sex-matched healthy control subjects (65.9±14.5 vs. 122.1±45.3, p<0.0001). In KCS patients, prednisolone treatment for 28 days resulted in a decrease in tear NGF levels, symptom scores and IC scores, whereas hyaluronic acid treatment had no such effect (68.2±25.0 pg/μg vs. 108.0±43.4 pg/μg, p