Exophiala phaeomuriformis keratitis in a subarctic climate region: a case report

To report a case of Exophiala phaeomuriformis mycotic keratitis in a patient from a subarctic climate region. Dematiaceous fungi (black yeasts) have been gaining importance as corneal keratitis and ulcer causative agents in certain regions, but no cases have been described in Scandinavia.

Case report of a patient with a persistent corneal erosion that eventually presented a brown-pigmented infiltrate. The patient had a history of several months of topical therapy comprising medication for glaucoma, corticosteroids and antibiotics. A therapeutic contact lens was used, and amniotic membrane transplantation was performed before the development of the pigmented infiltrate.

Exophiala phaeomuriformis was identified on the microbiological cultures from the surgically obtained infiltrate scrapes. The patient responded to topical amphotericin and fluconazole, the erosion was cured and a stromal scar subsided. During follow-up, sequential slit-lamp images and anterior segment optical coherence tomography (OCT) scans were obtained.

This is the first described case of keratitis caused by E. phaeomuriformis in a subarctic region, the first in Europe and, to our knowledge, the second reported case in the literature. It is important to remember that superficial corneal brown-pigmented infiltrates should raise the suspicion of an unusual fungal infection even in this climate. This is particularly important in patients with ocular surface disease treated with steroids and antibiotics for a long time.