The Quantitative Detection of Herpes Simplex Virus, Varicella Zoster Virus, and Cytomegalovirus DNAs in Recipient Corneal Buttons

Abstract
Purpose: We detected herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), varicella zoster virus (VZV), and cytomegalovirus (CMV) DNAs in recipient corneal buttons taken at the time of penetrating keratoplasty. Methods: Twenty-seven corneal buttons were obtained from 27 patients (10 men and 17 women), 7 of whom had a history of HSV keratitis. Excised corneal buttons were immediately frozen in liquid nitrogen in the operating theater and then stored at −80°C until DNA extraction. The detection of HSV-1, HSV-2, VZV, and CMV DNAs was carried out by a nested polymerase chain reaction (PCR) method. The genome copy numbers for the nested PCR-positive samples were subsequently quantified by real-time PCR. Results: HSV-1, HSV-2, VZV, and CMV DNAs were detected in 10, 1, 9, and 2 of the 27 recipient corneal buttons, respectively. HSV-1 or HSV-2 DNAs were also detected in 5 of 7 patients with a history of HSV keratitis. Both CMV-positive patients (patients 2 and 3) had ocular pemphigoid. Among the nested PCR-positive samples, 2 HSV-1, 1 HSV-2, 1 VZV, and 1 CMV sample could be quantified by real-time PCR. Copy numbers ranged from 19 to 928 copies. Conclusions: All 4 herpesviruses, including CMV, were detected in the corneal buttons. The relationship between CMV in the cornea and ocular diseases of the anterior segment should be further evaluated.