The relationship of graft survival and herpes simplex virus latency in recipient corneal buttons

Abstract

Purpose: To demonstrate relationship between herpes simplex virus (HSV) corneal latency and graft survival. Methods: Prospective case control study. 28 recipient corneal buttons and donor cornea-scleral remnants were examined for HSV DNA with polymerase chain reaction (PCR). None of the recipient had a history of HSV infection. Serum samples of graft recipients were analyzed for the presence of anti-HSV IgG and IgM with enzyme-linked immunosorbent assay technique. All corneas were free of stromal scarring or epithelial defect before sampling and had an endothelial cell density of >2000 cells/mm 2 . Results: In twenty three patients (82%) anti-HSV IgG was detected in serum. In none of the recipients anti-HSV IgM was positive. HSV DNA was positive in six out of twenty eight (21%) of the recipient corneal buttons and none of the donor cornea-scleral remnants. In eighteenmonths follow-up period three out of six (50%) HSV DNA positive and one out of twenty-two (4.5%) HSV DNA negative patients experienced late endothelial failure that was statistically signifi cantly different (p = 0.022). Conclusion: Even without a history of HSV keratitis, presence of latent HSV virus in recipient cornea is an important risk factor for subsequent graft survival.

PCR testing for herpesviruses in aqueous humor samples from patients with and without clinical corneal endothelial graft rejection

“…7 Therefore, the true prevalence of herpetic keratitis masked as AGR is likely to be even higher than estimated in this study. On the other hand, antibodies in AH cannot reliably detect a herpetic infection in the early phase, and the DNA in corneal tissue persist long after active infection has resolved, 25,26,30 limiting the usefulness of PCR test in corneal buttons. 18,35 An accurate estimation of prevalence would, therefore, likely require simultaneous testing with PCR and antibodies in AH, as well as PCR in corneal buttons, as these would complement each other and together provide a better understanding of the evolution of the disease over time.…”

“…The prevalence of HSV in corneal buttons from patients who have undergone PKP depends on the clinical history of HSV infection and ranges from 1.5% to 4% in patients with a negative HSV history 8,18 and 36%–82% in patients with a positive HSV history 8,18,24 . However, a positive polymerase chain reaction (PCR) test for HSV in a corneal button is not necessarily indicative of active viral infection 25,26 . In addition, a corneal button can be obtained only in cases of permanent graft failure requiring PKP, and thus does not provide evidence for the treatment of acute graft failure.…”

“…8,18,24 However, a positive polymerase chain reaction (PCR) test for HSV in a corneal button is not necessarily indicative of active viral infection. 25,26 In addition, a corneal button can be obtained only in cases of permanent graft failure requiring PKP, and thus does not provide evidence for the treatment of acute graft failure. In contrast, aqueous humor (AH), can be rapidly obtained and used to differentiate between allograft rejection (AGR) and viral endothelial keratitis, providing a viable diagnostic option in such cases.…”