case study
CASE STUDY: Recurrent Central Corneal Ulcer
This O.D. used a synergistic approach to treat and resolve the problem.
DOUGLAS K. DEVRIES, O.D.

Delayed or ineffective treatment of corneal infections may lead to devastating consequences including permanent visual impairment, making prompt, effective treatment essential. Treatment typically consists of systemic and topical broad-spectrum antibiotics until culture results identify the causative organism.

This image, captured with 35mm camera, was taken after removing the large, raised, white area of tissue in the center of the ulcer by corneal culture scraping. While blurred, the ulcer was surrounded by a dense 2mm ring of infiltrates.

Presentation and history

A 19-year-old, white male presented on a Friday morning with a two-day history of a red, irritated right eye. His ocular history revealed he wore soft contact lenses on a monthly basis. During the past week, he had some feelings of dryness and was removing the lenses often. This dryness caused increased symptoms of irritation. The patient was rewetting and cleaning the contacts with ReNu with MoistureLoc (Bausch & Lomb) contact lens solution.

His vision was 20/40 with pinhole in the affected eye with 1 to 2+ injection. The cornea had a paracentral, raised ulcer, approximately 0.8mm in size with a surrounding ring of sub-epithelial infiltrates. While the edges were not feathery, the ulcer was considerably elevated. Typically patients with an ulcer of this size, elevation and location would be considerably uncomfortable. Remarkably, this patient was not, nor was the eye as injected as we suspected. Given this patient's solution choice, we explored the possibility that the cause was fungal, even though its appearance was not typical. The patient's presentation suggests other possibilities, including a sterile or infectious cause.

Diagnostic testing

We elected to perform a corneal scraping to obtain a fungal culture. The picture on page 57 depicts the ulcer after removal of the raised lesion during scraping. We elected to treat this case as an infectious ulcer until proven otherwise. We then started the patient on antibiotic, non-steroidal antibiotic and non-steroidal anti-inflammatory (NSAID) therapy. We prescribed the anti-infective, Zymar ophthalmic solution (gatifloxacin 0.3%, Allergan), at an initial loading dose of instillation every 15 minutes for the first hour and q2h thereafter. We also prescribed the NSAID Acular LS (ketorolac tromethamine 0.4%, Allergan) q.i.d. to ease the discomfort and instructed the patient to return to our clinic the next day.

Follow-up

When the patient returned for follow-up the next day, the epithelial defect remained approximately the same size. However, the surrounding sub-epithelial infiltrates had increased two fold. Even with the increase in infiltrates, the patient reported less discomfort than the previous day. This was no doubt due to Acular's analgesic effect. Since the defect itself did not grow, we elected to proceed with steroid therapy � PredForte (prednisolone acetate 1%, Allergan) four times a day. We also instructed the patient to call the clinic if discomfort increased during the night or on Sunday and made arrangements for him to see an O.D. in his hometown on Monday.

On Monday, the patient presented with the epithelial defect healed and substantially reduced sub-epithelial infiltrates. We considered the etiology to be infectious rather than fungal and the lab culture eventually substantiated this diagnosis.

Discussion

While we waited for culture results to rule out the possibility of a fungal ulcer, we started the patient on an anti-infective, analgesic therapy. Because the defect did not enlarge the next day, we added an additional anti-inflammatory component. We controlled the patient's relative discomfort, attacked the potential bacterial and eventually calmed the eye with a steroidal suspension. Fortunately, the ulcer proved not to be fungal and the patient healed well with no decrease in visual acuity.

While we did not know the cause of this patient's ulcer upon presentation, prompt treatment of corneal infection cases is key to preventing or at least limiting potential corneal damage and visual impairment.

This synergistic treatment met all of our primary goals: identification of the ulcer's underlying cause and relief for the patient from all complications, discomfort and pain.