Short CommunicationMeasure of herpesvirus-specific ocular antibody production in patients with uveitis

BackgroundThe amount of specific antiviral IgG in aqueous humour (AH) provides a major contribution to the diagnosis of herpesvirus uveitis. Ocular antibody production is often evaluated by comparing levels of specific and total IgG in serum and AH. The small volume of AH is a major limit for diagnosis.ObjectivesTo simplify the measure of ocular antibody production, we tested the quotient of serum/AH ratios of specific and control antiviral IgG, using automated quantitative serology methods on minimal volumes of AH, in confirmed and suspected herpesvirus uveitis.Study designSerum and AH samples from herpesvirus PCR-positive uveitis patients, and from PCR-negative cases who were highly suspected to have viral uveitis were retrospectively analysed for ocular production of specific antiviral IgG using 40 μl of AH, and quantitative Enzygnost ELISA-based methods. Cataract and Fuchs cyclitis cases were used as controls.ResultsOcular production of specific antiviral IgG was demonstrated in 32 (51.6%) of 62 herpesvirus PCR-positive uveitis cases, in none of 42 controls, and in 21 (55.2%) of 38 PCR-negative cases clinically suspected to have herpesvirus uveitis. The test had absolute specificity, and its sensitivity depended on the virus, pathology and timing of sampling.ConclusionOcular antibody production can be measured by simple quantitative ELISA-based methods on serum and minimal volumes of AH. This specific and sensitive test, implemented in the routine virology laboratory should help the diagnosis and specific antiviral therapy management of herpesvirus uveitis.