Detection of herpes simplex virus type 1, 2 and varicella tester virus DNAin recipient corneal buttons

Aim-To study the value of polymerase chain reaction (PCR) analysis, to dete ct viral DNA in recipient corneal buttons taken at the time of penetrating keratoplasty (PKP) in patients with an initial diagnosis of herpetic stroma l keratitis (HSK). Since HSK has a tendency to recur, an accurate diagnosis of previous HSK could be the reason to start antiviral treatment immediate ly, thereby possibly decreasing the number of graft failures due to recurre nt herpetic keratitis. Methods-Recipient corneal buttons and aqueous humour (AH) samples were obta ined at the time of PKP from HSK patients (n=31) and from other patients (n =78). Eye bank corneas were also used (n=23). Herpes simplex virus type 1 ( HSV-1), type 2 (HSV-2), and varicella tester virus (VZV) infection were ass essed by PCR and antibody detection. Results-The clinical diagnosis HSK could be confirmed by PCR for HSV-1 in 1 0/31 (32%). In these corneal buttons HSV-2 DNA was detected in 1/31 (3%) an d VZV DNA in 6/31 (19%). Intraocular anti-HSV antibody production was detec ted in 9/28 AH samples tested (32%). In the other patient derived corneas H SV-1 DNA was detected in 13/78 (17%), including eight failed corneal grafts without clinically obvious herpetic keratitis in the medical history. In c lear eye bank corneas HSV-1 was detected in 1/23 (4%). Conclusions-PCR of HSV-1 on corneal buttons can be a useful diagnostic tool in addition to detection of intraocular anti-HSV antibody production. Furt hermore, the results were suggestive for the involvement of corneal HSV inf ection during allograft failure of corneas without previous clinical charac teristic signs of herpetic keratitis.