Delayed-onset postoperative endophthalmitis secondary to Exophiala

Abstract

Exophiala is a genus of slow-growing, melanin-producing, saprophytic fungi most commonly found in soil, faeces and decaying plant matter. It is an unusual fungal pathogen capable of causing a variety of ophthalmic manifestations, including keratitis, scleritis and endophthalmitis. In this report, we present a rare case of delayed-onset postoperative endophthalmitis confined to the anterior segment, secondary to Exophiala species. Previous reported cases of delayed-onset postoperative endophthalmitis have been treated medically, with suboptimal outcomes. Our experience supports the use of anterior segment surgery to clear the nidus of disease combined with intravitreal voriconazole to prevent recurrence of the infection.

Figure 1

Preoperative slit lamp photograph of the patient's right eye. Pigmented fungal elements are visible on the corneal endothelium centrally. A yellow coagulum occupying the anterior chamber prohibits visualisation of the rest of the eye.

Figure 2

Preoperative ultrasonography of the patient's right eye. The anterior chamber is formed with moderately dense opacities surrounding the iris and intraocular lens. In the posterior segment, the retina is attached and there are no significant vitreous opacities or membranes.

Figure 3

Histopathological examination of the patient's corneal button. On periodic acid-Schiff (PAS) staining (×4), there is attenuation of the corneal endothelium and Descemet's membrane. Amorphous inflammatory debris is present in the anterior chamber containing lymphocytes, acellular debris and pigmented PAS-positive fungal elements. On Gomori methenamine silver (GMS) staining (inset, upper right, ×20), the presence of GMS-positive fungal hyphae and budding yeasts is confirmed. Gram and acid-fast staining were negative (not shown).

Figure 4

Slit lamp photograph at postoperative week 7. The penetrating keratoplasty graft is clear centrally with evidence of peripheral neovascularisation at the graft host junction. There are a few keratic precipitates consistent with early graft rejection, but no hypopyon or other signs of infection.