CHALLENGES IN THE MANAGEMENT OF FUNGAL KERATITIS – CASE REPORT

Corneal infections are an important cause of blindness worldwide. Fungal keratitis (FK) represents one of the most severe forms of corneal infections due to its difficult diagnosis and treatment. The use of contact lens without proper hygiene conditions has become an important risk factor for FK in developed countries. Other factors are ocular trauma, previous ocular diseases, the use of topical corticosteroids and systemic immunosuppression. An early and accurate diagnosis is crucial to implement an appropriate treatment in a timely manner and to avoid potential complications and irreversible visual loss.

Coimbra University Hospital Centre (CHUC), Coimbra, Portugal

A healthy 52-year-old contact lens wearer, presented on the emergency room (ER) with a 7-day history of foreign body sensation, redness and itching on the right eye. She mentioned an episode of ocular trauma with organic matter after sweeping a balcony. Slit-lamp examination showed a 2mm corneal epithelial defect and stromal infiltrative. No abnormalities were detected in left eye. Microbial specimens were collected, and the patient started on topical ciprofloxacin ointment and tobramycin and ceftazidime eye drops. Due to the lack of clinical improvement, with deterioration of best visual acuity (1/10) and worsening of the stromal infiltrate, the patient was admitted and, suspecting a diagnosis of keratomycosis, antifungal treatment was started with oral - posaconazole (300mg/day) and voriconazole 10mg/ml eye drops every hour. The microbiological analysis revealed the fungus Fusarium spp. With the diagnosis of Fusarium keratitis, intrastromal and intracameral voriconazole were performed 3 times and intravenous voriconazole added to the treatment. Despite the topical and systemic antifungal therapy, there was no clinical improvement and, due to the risk of perforation, a tectonic penetrating keratoplasty (PK) was performed. Tectonic PKs were performed again twice over the next 3 months, first because of a new fungal infiltrate in the first corneal graft and second because of corneal graft melt and perforation. The patient was continued on oral Posaconazole and topical voriconazole and amphotericin eyedrops. After her 3^rd PK, chlorhexidine and povidone iodine diluted eyedrops twice a day were added to the treatment regimen. With this new regimen, the corneal graft remained clear, with no signs of fungal recurrence or inflammation.

Fungal keratitis is an important cause of ocular morbidity and blindness. It represents a clinical challenge due to its difficult differential diagnosis from other microbial keratitis. Fungus identification using microbiological techniques is essential for an early diagnosis, which allows the timely treatment and avoids irreversible complications. We report a case that documents the effectiveness of topical iodine povidone as an adjunctive treatment for refractory Fusarium keratitis, resistant to other triazoles and conventional antifungals.