Treatment of HSV-1 stromal keratitis with topical cyclosporin A: a pilot study

Background: In stromal keratitis induced by herpes simplex virus (HSV) the host's immune response contributes to corneal scarring and neovascularizati on. The purpose of this study was to analyze the efficacy of topically appl ied cyclosporin A (CsA) in patients with HSV keratitis. Methods: The author s performed a prospective pilot study in patients with HSV stromal keratiti s (n=18). Eyes were treated with CsA eyedrops and acyclovir ointment. The d rugs were tapered off gradually. Visual acuity, slit-lamp appearance, intra ocular pressure and corneal sensitivity were evaluated monthly (follow-up 5 .2+/-0.28 months, mean+/-SEM. Results: Keratitis resolved with CsA treatmen t in 10 of 14 patients with non-necrotizing keratitis and in 2 of 4 with ne crotizing keratitis. As CsA was used topically, the corticosteroids could b e withdrawn in all patients with non-necrotizing keratitis and in 1 of 3 wi th necrotizing keratitis. Under CsA therapy, persistent or progressive infl ammation was noted in 6 of the 18 patients. These 6 patients with keratitis improved only with combined CsA/corticosteroids. Corneal ulcers healed in 4 patients with topical CsA, and corneal neovascularization improved in a f urther 8. Except for toxic epitheliopathy, no further CsA complications wer e noted. Conclusions: The findings in this pilot study suggest that HSV str omal keratitis can be treated successfully with CsA eyedrops, especially in non-necrotizing disease. CsA may be particularly helpful in the presence o f steroid glaucoma, herpetic corneal ulcers, and to taper off topical corti costeroids. Additional use of acyclovir may aid in suppressing the recurren ce of epithelial HSV keratitis. A randomized study should be performed to e valuate the role of topical CsA in more detail.