Unilateral peripheral corneal thinning with negative workup: April consultation #1

Abstract

A 38-year-old Hispanic man with a 3-month history of presumed fungal keratitis in the right eye was referred to our facility for further management. Initially, the patient presented with a small corneal infiltrate in the peripheral aspect of the right cornea to an outside ophthalmologist who had obtained a bacterial culture and placed the patient on 2 fortified topical antibiotics. After 1 week of aggressive antibiotic treatment with negative culture results, the patient’s symptoms of redness and photophobia had deteriorated and the referring doctor noted 2 additional satellite lesions. The patient was placed on topical natamycin 5.0%. After 1 week of treatment with natamycin, the satellite lesions were reported to have resolved with some improvement in the patient’s subjective symptoms of redness and pain; however, the area of initial infiltrate had enlarged and the other symptoms had not improved. The patient was then referred to our facility. Although the patient works in an agricultural field and rides the tractor, he denies work-related trauma to the eye. His medical and ocular histories are unremarkable, and he was not taking systemic medication. However, the patient was using natamycin every 3 hours in the right eye. During the initial examination at our facility, he reported mild pain and discomfort with moderate photophobia and redness in the right eye without discharge. His uncorrected distance visual acuity was 20/40 in the right eye and 20/20 in the left eye with 2+ conjunctival injection in the right eye. A slitlamp examination showed peripheral thinning involving the nasal aspect of the right cornea by approximately 3 clock hours with overhanging edges with a few inferior satellite keratic precipitates. The