HSV keratitis treatment recommendations take trial evidence, clinical experience into account

Evidence-based medicine has provided some guidance on the management of herpes simplex virus (HSV) keratitis, but there are still many questions left unanswered, said Thomas J. Liesegang, MD, at the World Congress of Ophthalmology.

Based on the findings from The Herpetic Eye Disease Study (HEDS) project and his own experience, Dr. Liesegang offered some suggestions to the audience at a session highlighting a potpourri of clinical pearls from American Academy of Ophthalmology board members.

For epithelial HSV keratitis, topical antiviral treatment is appropriate whereas oral acyclovir (Zovirax) started during acute dendritic or geographic keratitis does not prevent stromal disease. Once there is disciform or necrotizing stromal HSV keratitis, topical steroids should be used as they have been shown to hasten resolution without causing recurrent herpetic keratitis.

"In one HEDS trial, oral acyclovir was found ineffective for treating non-necrotizing stromal keratitis. However, there is a strong rationale for its use in necrotizing keratitis," said Dr. Liesegang, professor of ophthalmology, Mayo Clinic, Jacksonville, FL.

For eyes with iridocyclitis, limited data from a prematurely terminated HEDS study showed oral acyclovir may be effective, and Dr. Liesegang noted he prescribes a topical steroid in that situation. In another HEDS trial, oral acyclovir 400 mg BID given for 1 year after the onset of active HSV was demonstrated to decrease the recurrence of epithelial and stromal HSV keratitis.

Dr. Liesegang noted that antiviral treatment in the HEDS studies was limited to oral acyclovir and topical trifluridine (Viroptic).

"Now, other antiviral agents with better bioavailability are available and they may be effective. However, we still have no agents that are effective against latent HSV and there is no indication that a vaccine will be immediately available," he said.