Clinically, it is often difficult to differentiate between fungal and bacterial infections. Fungal keratitis is an infrequent cause of microbial Smad phosphorylation keratitis among contact lens wearers and may occur in 4% to 27% of such cases, depending on the type of lenses.12 A recent outbreak of Fusarium

keratitis in the United States has caused a recall of contact lens fluid by the FDA.13–15 Fungi frequently contaminate contact lens paraphernalia or the lens itself. The most frequently noted predisposing factor for fungal keratitis was improper lens care, which led to contamination of the contact lens treatment fluids and cases.16 In our case, the use of once-daily contact lens, as well as the negative cultures taken from the same batch of lens, makes such a possibility highly unlikely. The diagnosis of Fusarium keratitis should be suspected in every case of “soilborne” keratitis unresponsive to antibacterials. However, the ultimate way to reach a definitive diagnosis is by Sabouraud’s agar cultures and direct visualization of the fungi from corneal scrapings. Microscopic examination may mistakenly identify Oligomycin A supplier the case as aspergillosis, as occurred in our case,

because histopathology reveals acute-branching septate hyphae similar to those found in aspergillosis.5 A close collaboration is therefore needed between ophthalmology–pathology–microbiology and the infectious diseases team. Recent reports have proposed a role for confocal microscopy in the early diagnosis of infectious keratitis.17 Although confocal microscopy cannot show bacteria, it is Nutlin-3 solubility dmso useful in the identification of Acanthamoeba and fungal filaments. While cultures and smears remain the standard diagnostic methods for evaluating bacterial and fungal keratitis, they are lengthy processes and may take days and even weeks to obtain growth. Confocal microscopy offers a rapid in vivo visualization of the fungal filaments, allowing immediate initiation of treatment. However, reports of the use of this method remain anecdotal and at this time evidence is lacking to support

it as the only diagnostic method of fungal keratitis.18 Treatment consists of removal of the contaminated lens in addition to topical and probably systemic antifungal agents.19,20 Topical natamycin is the treatment of choice, given its excellent antifusarial activity in vitro, its corneal penetration, and its safety profile.21 We present the beneficial use of topical (and systemic) voriconazole in the treatment of such severe cases. Furthermore , in severe or recurrent cases of ocular fungal infections, systemic antifungal agents such as posaconazole, itraconazole, or voriconazole may be used.19 If therapy is delayed, fusarial keratitis may progress to endophthalmitis. Hence, rapid and accurate diagnosis of keratitis is essential if vision is to be preserved.