Abstract
Abstract: :
Purpose: To detect herpes simplex virus (HSV) genome in the cornea, we sampled eye–bank corneal buttons and recipient's corneas and quantitated HSV genome in them by a real– time PCR. Methods: Forty–four recipient corneas: 7 corneas with history of herpetic keratitis, 37 corneas without it: 70 eye–bank donor corneas and 35 eye–bank donor scleras. Primers for a real–time PCR were selected in a HSV–1 and 2 common region of viral DNA polymerase. A conventional PCR was designed to detect HSV–1,–2 and varicella zoster virus (VZV). When the cornea was positive for HSV–1 by both PCR methods, we considered it as the HSV–1 positive. Results: A real–time PCR was more sensitive than a conventional PCR. A real–time PCR had a wide linear range from 1 to 107 copies. The values of coefficient of variation intra– and inter–assay were 3.0% and 10.1%, respectively. HSV–1–DNA was detected in 71.4% of the corneas with history of herpetic keratitis: (1.9±1.8)×104 copies/mg (mean±S.E.M.), and in 10.8% of the corneas without it: (8.7±7.9) copies/mg. The detection rate and the amount of HSV–DNA in the corneas with history of herpetic kesratitis were significantly higher than those in the corneas without it (P<0.01: Fisher’s exact test, P<0.01: Mann–Whitney U test, respectively). There was a patient who suffered from herpetic keratitis after PKP, although he had no history of herpetic keratitis. His cornel smear had HSV–1 genome (although his cornea was quiescent when it was sampled) at the time of his corneal tranplantation. HSV–1–DNA was detected in 5.7% of the eye–bank donor corneas: (4.9±3.4)×102 copies/mg, and in 8.6% of the donor scleras: (8.1±6.3) copies/mg. HSV–1–DNA was also positive in 66.7% of the corneas when they had been sampled from the scleras containing HSV–1 genome. HSV–2 and VZV–DNA were not detected in these samples. Conclusions: A real–time PCR can quantitate HSV–1 genome in the cornea even at the quiescent phase of the infection. HSV–1 genome was detected in the corneas without past history of herpetic keratitis by this methoid. CR:None
Keywords: herpes simplex virus • keratitis • varicella zoster virus