Multidrug-resistant Fusarium keratitis: diagnosis and treatment considerations

Abstract

Mycotic keratitis is an ocular infective process derived from any fungal species capable of corneal invasion. Despite its rarity in developed countries, its challenging and elusive diagnosis may result in keratoplasty or enucleation following failed medical management. Filamentous fungi such as Fusarium are often implicated in mycotic keratitis. Bearing greater morbidity than its bacterial counterpart, mycotic keratitis requires early clinical suspicion and initiation of antifungal therapy to prevent devastating consequences. We describe a case of multidrug-resistant mycotic keratitis in a 46-year-old man who continued to decline despite maximal therapy and therapeutic keratoplasty. Finally, enucleation was performed as a means of source control preventing dissemination of a likely untreatable fungal infection into the orbit. Multidrug-resistant Fusarium is rare, and may progress to endophthalmitis. We discuss potential management options which may enhance diagnosis and outcome in this condition.

Figure 1

Slit-lamp photographs. Notes: (A) a large stellate-shaped epithelial defect with multiple stromal satellite infiltrates overlying the inferior visual axis on presentation. The grey–white stromal infiltrates had feathery margins and raised sloughy borders with associated conjunctival injection, dilated iris vessels and a mild anterior chamber reaction. (B) Clinical deterioration: enlarging central epithelial defect and coalescing stromal infiltrates with pronounced conjunctival injection, corneal oedema and hypopyon. Poor treatment response required revision of medical management to include broadening antimicrobial cover and treatment consideration of atypical agents including viral, fungal and Acanthamoeba. (C) Therapeutic penetrating keratoplasty performed on day 26. Fungal invasion seen on the iris intraoperatively.

Figure 2

Newly devised protocol. Notes: adapted from fungal keratitis management guidelines (Sandwell and West Birmingham Hospitals, UK). DM, diabetes mellitus.