Pathogenesis and management of herpes simplex virus keratitis.

Herpes simplex keratitis (HSK) remains a common cause of unilateral corneal disease. Despite intense research over three decades, the mainstay of therapy continues to be topical and, more recently, systemic acyclovir plus topical corticosteroid in some cases. There is increasing recognition that HSK after keratoplasty can occur not only as a result of recurrence in patients with HSK, but also in patients with other primary diagnoses as a result of activation of HSV in the host, or by transmission of virus in the donor tissue.