Case Report: Managing Antiviral Resistant Herpes Simplex Keratitis

Eye Test
Clinicians recommend ​​famciclovir in cases of antiviral resistant herpes simplex keratitis.

This article is part of Optometry Advisor’s conference coverage from the 2021 meeting of the American Academy of Optometry, held in Boston from November 3 to 6, 2021. The team at Optometry Advisor will be reporting on a variety of the research presented by the primary eye care experts at the AAO. Check back for more from the AAO Optometry 2021 Meeting..

Patients with an antiviral resistant herpes simplex keratitis ocular infection should receive prompt treatment with famciclovir, according to a case report presented at the American Academy of Optometry 2021 meeting held in Boston, November 3-6, 2021.

Ocular infection with herpes simplex may lead to visual morbidity dependent on the rate of recurrence. Patients should be treated promptly to minimize risk for immune-mediated cellular damage and other ocular complications including stromal scarring and decreased vision.

Studies have shown that both topical and oral therapies are effective at treating herpes simplex ocular infections; however, there remains a paucity of data about antiviral resistance among ocular infections. Here, a case report of an ocular infection with a resistant strain was discussed.

An 89-year-old patient presented with new onset blurred vision and mild ocular irritation. During an ocular examination, the patient was found to have a large (6 mm) herpes simplex dendrite in the right eye.

The patient was given ganciclovir (5/day). At day 10, the corneal dendrite remained, and the patient was given acyclovir.

After 2 weeks of acyclovir therapy, the corneal dendrite began to worsen. At this point, the clinicians suspected the patient had an antiviral resistant infection and the patient was switched from acyclovir to famciclovir.

After 1 week of famciclovir therapy, the herpetic infection was cleared.

An epithelial herpes simplex infection can be treated with oral, topical, or combined therapies, however, in cases of resistant infections, resistance to acyclovir is most common. Patients with a resistant infection should be treated with famciclovir and not valacyclovir, as valacyclovir is a prodrug of acyclovir and is therefore more prone to cross resistance.

Clinicians who are treating patients who are immunocompromised should be aware of antiviral resistant treatment strategies, as antiviral resistance is more common among patients who are immunocompromised (3% to 10%) compared with the general population (0.1% to 0.7%).

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Minnick J, Acharya R. Antiviral resistance in the treatment of herpes simplex keratitis. Poster presented at American Academy of Optometry 2021; November 3-6-; Boston. Board #50