The detection of herpesviral DNA in aqueous fluid samples from patients with Fuchs' heterochromic cyclitis

Members of the herpesvirus family have been found in association with a variety of intraocular inflammatory conditions. The aetiology and pathogenic mechanisms underlying the specific uveitis entity Fuchs' heterochromic cyclitis (FHC) have yet to be determined. This study investigates the presence of specific herpesviral DNA in samples of aqueous fluid from patients with FHC. Aqueous humour was obtained from 40 patients undergoing cataract surgery, 20 patients with a clinical diagnosis of FHC and to patients with senile cataract who acted as controls. Each sample was tested for the presence of Epstein-Barr virus (EBV), cytomegalovirus (CMV), herpes simplex virus (HSV) and varicella-zoster virus (VZV) DNA after initial amplification with virus specific primers using the polymerase chain reaction (PCR). Herpesviral DNA could not be detected in any of the aqueous samples from the FHC patients. Although a viral aetiology is unlikely, this study cannot exclude the possibility that a virus may be the initiating factor in the development of FHC or that virus may be sequestered in different ocular tissues. Control patients also showed no significant carriage of herpesvirus in their aqueous humour implying that detection of any herpesviral DNA in aqueous samples may be clinically relevant.