Consider Low-potency Topical Steroids for Treatment of Stromal Keratitis in HZO

When recognized and treated early using topical steroids, HZO patients who developed stromal keratitis in the ZEDS trial experienced no significant decline in visual acuity by one year. Photo: Chris Sindt, OD. Click image to enlarge. The Zoster Eye Disease Study (ZEDS), which published its results in 2024, endorses the administration of a daily dose of 1000mg of valacyclovir over a period of 12 months to decrease the incidence of new, worsening or recurrent episodes of keratitis or iritis in patients with herpes zoster ophthalmicus (HZO). Given that stromal keratitis (SK) is the most common clinical manifestation of HZO, researchers recently performed a secondary analysis of ZEDS data to better understand the presentation, treatment and visual outcomes of this ocular complication. They concluded that timely intervention and the use of low-potency topical steroids can effectively manage SK, ultimately leading to favorable visual outcomes without the need for high-potency therapies.The ZEDS was a double-masked, placebo-controlled randomized clinical trial conducted from November 2017 to June 2024, involving 95 sites across the USA, Canada and New Zealand. A total of 527 participants diagnosed with HZO were enrolled, of which 105 (20%) experienced recurrent, new or worsening SK. Participants were randomly assigned to receive either 1g oral valacyclovir daily or a placebo for one year. Follow-up assessments occurred every three months, with key outcomes focusing on the recurrence and worsening of SK. Notably, the trial's methodology allowed investigators the discretion to use open-label valacyclovir and topical steroids to treat any complications that developed.Of the 105 participants diagnosed with SK, 50% were already using topical steroids when SK was identified. Among patients who had stopped using topical steroids, 38% had ceased their use in the three months leading up to the endpoint, which the researchers note indicates that topical steroids may serve as a protective measure against the recurrence of SK. Moreover, the researchers noted in their paper, which was recently published in American Journal of Ophthalmology, that “low-potency topical steroids [appeared] no less effective than high-potency topical steroids for treatment and ongoing suppression of recurrent, new or worsening SK in HZO with complications, and may be preferable, as a means of reducing steroid-associated side-effects.”When treated promptly with topical steroids and followed regularly, ZEDS patients with SK had good visual outcomes, generally without the addition of oral antiviral therapy. Baseline visual acuity scores showed a mean logMAR best-corrected vision of approximately 20/25, which demonstrated minimal decline over the 12-month follow-up. Important to note is that 75% of SK instances were detected at scheduled study visits, suggesting that the occurrence of SK requiring treatment is often asymptomatic.Reflecting on these findings, the researchers concluded, “Individuals with ocular complications of HZO who develop SK generally maintain very good vision without use of oral antiviral therapy when monitored closely and SK is recognized and treated.” Therefore, they argued, “Low-potency topical steroids should be considered for treatment and ongoing suppression of SK in HZO.”Click here for the journal source. Jacobs DS, Lee TF, Asbell P, et al. Stromal keratitis in the zoster eye disease study (ZEDS): lessons learned. Am J Ophthalmol. February 6, 2026. [Epub ahead of print]. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.