Findings In Detection Of Herpesviridae By Real-time Polymerase Chain Reaction And Intraocular Antibody Production In A Case-series Of Anterior Uveitis

Abstract

Purpose: : To determine the result of real-time polymerase chain reaction (rt PCR) and intraocular specific antibody secretion (Goldmann-Witmer coefficient) for Herpesviridae on samples from a series of anterior uveitis. To target the use of these two biologic tests in the diagnostic of Viral Herpesviridae anterior uveitis by the consideration of clinical behavior and delay of intraocular sampling. To address the important issue of the prevalence of CMV etiology among cohort of patients with severe anterior uveitis of unclear diagnosis.

Methods: : Aqueous humor samples were collected from patients suspected of having anterior uveitis of infectious origin at presentation (41 samples). The diagnosis of infectious uveitis was confirmed by quantification of antibodies with the Goldmann-Witmer coefficient (GWC) and/or for detection of Herpesviridae genomes with rt PCR.The data were compared with data of 20 control samples taken from patients with HLA B-27 positive anterior uveitis (n=8), Behçet disease (n=6), Fuchs' heterochromic cyclitis (FHC) (n=4), sarcoidosis anterior uveitis (n=1) and multiple sclerosis (MS) related uveitis (n=1). The control group was used to calculate the specificity of the tests.

Results: : In viral Herpesviridae anterior segment infection GWC results were positive from 24 hours, although PCR was not significant until 5 days after onset of signs.Fifteen out of 41 patients (36.5%) had a final diagnosis of anterior segment infectious uveitis of Viral origin (Herpesviridae) confirmed by PCR positive result (5/15 patients) and/ or Specific intraocular antibody synthesis (13/15 patients); or clinical behaviour and response to treatment suggested could not rule-out Herpes virus (19/41 patients, 46%). Among them five anterior uveitis were CMV-associated: Posner Schlossman syndrome (n=1), hypertensive anterior uveitis without iris atrophy (n=3) or non granulomatous normotensive anterior uveitis without iris atrophy (n=1), by intraocular biological testing. GWC testing for CMV was positive in all 5 patients diagnosed with CMV associated anterior uveitis

Conclusions: : For the diagnosis of presumed Herpesviridae associatedanterior uveitis, due to the lack of diagnostic gold standard, usefulness of laboratory diagnosis tools (rt PCR and GWC) depends from parameters other than the sensitivity of the tests. We determined though greatest use of viral PCR and GWC is its high specificity.While the GWC is progressively less often performed for economic and time consuming reasons, our findings suggest that it still has a role in anterior uveitis suspected of Herpesvirus etiology.

Keywords: uveitis-clinical/animal model • herpes simplex virus • cytomegalovirus