Herpes simplex keratitis (HSK) is a common yet potentially blinding condition caused by a primary or reactivated herpetic infection of the cornea.1 The Herpetic Eye Disease Study established the standard of care in HSK management.2 Treatments range from oral antivirals and artificial tears to topical antibiotics, amniotic membranes, and corneal transplantation.3 Patients with immune stromal keratitis (ISK) may experience low-grade chronic keratitis for years.4 ISK is classified by a cellular and neovascularization infiltration of the cornea.5 We present a case of a patient with recurrent ISK and review its presentation, diagnosis, and management.
Case Presentation
A 52-year-old man presented to the eye clinic with a watery and itchy right eye with mildly blurred vision. His ocular history was unremarkable. His medical history was notable for hepatitis C, hypertension, alcohol and drug dependence, homelessness, and a COVID-19–induced coma. His medications included trazodone, nifedipine, clonidine HCl, and buprenorphine/naloxone.
On clinical examination, the patient’s best-corrected visual acuity was 20/40 in the right eye and 20/20 in the left. Corneal sensitivity was absent in the right eye and intact in the left. Anterior segment findings in the right eye included 360-degree superficial corneal neovascularization, deep neovascularization temporally, scattered patches of corneal haze, epithelial irregularity, and 2+ diffuse bulbar conjunctival injection (Figure 1). The anterior segment of the left eye and the posterior segments of both eyes were unremarkable. The differential diagnosis included HSK, syphilis, Cogan syndrome, varicella-zoster virus keratitis, Epstein-Barr virus keratitis, and Lyme disease. With consultation from a corneal specialist, the patient was given the presumptive diagnosis of ISK in the right eye based on unilateral corneal presentation and lack of corneal sensitivity. He was treated with 1-g oral valacyclovir HCl 3 times daily and 1 drop of prednisolone acetate 1% suspension 3 times daily in the right eye.
The patient returned a week later having only used the prednisolone drops for 2 days before discontinuing. Examination showed no change in his corneal appearance from the previous week. The patient was counseled on the importance of adherence to the regimen of topical prednisolone and oral valacyclovir.
The patient followed up 2 weeks later. He reported good adherence to the ISK medication regimen. His symptoms had resolved, and his visual acuity returned to 20/20 in the right eye. Slit-lamp examination showed improvement in injection, and the superficial corneal neovascularization had cleared. A trace ghost vessel was seen temporally at a site of deep neovascularization (Figure 2). He was instructed to continue valacyclovir once daily and prednisolone drops once daily in the right eye and to follow up in 1 month.
At the 1-month follow-up, the patient’s signs and symptoms had reverted to his original presentation. The patient reported poor adherence to the medication regimen, having missed multiple doses of prednisolone drops as well as valacyclovir. The patient was counseled again on the ISK regimen, and the prednisolone drops and 1-g oral valacyclovir were refilled. A follow-up visit was scheduled for 2 weeks. Additional follow-up revealed a resolved corneal appearance and bimonthly follow-ups were scheduled thereafter.