A RARE CASE OF PERSISTENT EPITHELIAL DEFECT AND DECREASED CORNEAL SENSATION CAUSED BY CORYNEBACTERIUM PROPINQUUM KERATITIS

To report the case of a patient with a central persistent epithelial defect (PED) and decreased corneal sensation due to Corynebacterium Propinquum Keratitis.

Department of Ophthalmology, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal.

A 51-year-old woman presented at the ophthalmology outpatient clinic with complaints of blurred vision and hyperemia in her left eye (LE) for one week. She had no complaints of discomfort or pain. The patient was a contact lens wearer and had a history of left acoustic neuroma removal, thyroid eye disease, and concomitant lagophthalmos.

Biomicroscopy of the LE revealed a 3 × 3 mm central epithelial defect with mild signs of ulceration. A cotton-tipped swab was used to collect the ulcer base exudate for bacterial culture. Pseudomonas aeruginosa Keratitis was presumed, and the patient initiated topical moxifloxacine and tobramycin. At 2-weeks of follow-up, the patient maintained a central epithelial defect and minimal improvement, despite the optimized medical therapy, and the bacterial culture was uneventful. Due to the lack of corneal sensation, a possible neurotrophic component was suspected and the patient initiated plasma rich in growth factors. A therapeutic contact lens and prophylactic topical fluoroquinolone were also applied. After three days, the patient presented with an increase of the PED and corneal exsudate. The Bacterial culture was repeated and a Corynebacterium Propinquum, which was only susceptible to Gentamicin, was isolated. Fortified topical Gentamicin was readily initiated and the PED resolved in 7 days. 

Pseudomonas Aeruginosa Keratitis is often the presumed diagnosis of contact lens users’ corneal infections. In cases of atypical presentation, less common bacterial agents must be considered alongside other pathogens. Corynebacterium spp. Keratitis may present with decreased corneal sensation and fluoroquinolone resistance, leading to misdiagnosis with Neurotrophic Keratitis.