Purpose: To measure the genomic DNA from Epstein-Barr virus (EBV) in ocular fluids and to analyze the clinical relevance of EBV in uveitis.
Methods: Intraocular fluids (30 aqueous humor and 30 vitreous fluid samples) were taken from 55 patients with uveitis after informed consent was obtained. Samples were assayed for EBV DNA using qualitative multiplex polymerase chain reaction (PCR) and quantitative real-time PCR. Antibodies to EBV were examined using a complement fixation test.
Results: EBV DNA was detected in 17 of 60 samples (28%) and 16 of 55 patients (29%) using multiplex PCR. However, only three of the 17 samples showed significantly high copy numbers of EBV DNA with real-time PCR. EBV DNA was not detected in the serum of all patients. EBV-specific antibodies were positive in the serum of all patients, but not in the vitreous fluid. Vitreous anti-EBV antibodies were positive only in patients displaying genomic DNA of EBV in the vitreous samples.
Conclusions: EBV DNA was detected by qualitative PCR in ocular fluids of many uveitis patients, but only a small proportion of patients showed high viral loads on quantitative real-time PCR, indicating that replication of the virus takes place only in a few patients.