Fungal Keratitis Secondary to Trametes betulina: A Case Report and Review of Literature.
OBJECTIVE
We report the first case of human infection and keratitis secondary to Trametes betulina, a rare filamentous fungus.


METHODS
Clinical examination including external and slit-lamp examination and corneal scrapings with microbiologic evaluation were performed on a patient with chronic allergic conjunctivitis, entropion and a long-standing corneal ulcer resistant to treatment.


RESULTS
The culture from the corneal scraping revealed a basidiomycetous fungus which was submitted for identification. DNA extraction with sequencing and analysis of the ITS and D1/D2 regions were performed on the isolate and demonstrated 100% similarity to Lenzites betulina/Trametes betulina. Susceptibility testing demonstrated potent in vitro activity of voriconazole (MIC < 0.03 μg/ml). The patient was treated with voriconazole, and the corneal ulcer and infiltrate resolved. The infection resulted in corneal thinning and a dense central corneal scar. Penetrating keratoplasty was performed 5 months after diagnosis and treatment and revealed stromal scarring without fungal elements.


CONCLUSIONS
This is the first reported case of keratitis caused by Trametes betulina. This organism should be considered in the differential diagnosis for rare filamentous fungal keratitis and its treatment with voriconazole also noted.
Jones Eye Institute, University of Arkansas for Medical Sciences (UAMS), 4301 W. Markham St., Little Rock, AR, 72207, USA. jshardin@uams.edu.
Joshua S
JS
Hardin
Department of Pathology, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
Deanna A
DA
Sutton
Department of Pathology, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
Nathan P
NP
Wiederhold
Department of Pathology, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
James
J
Mele
Jones Eye Institute, University of Arkansas for Medical Sciences (UAMS), 4301 W. Markham St., Little Rock, AR, 72207, USA.
Sunali
S
Goyal
D000368:Aged; D000935:Antifungal Agents / Q000494:pharmacology; D003315:Cornea / Q000382:microbiology*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D006801:Humans; D007634:Keratitis / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology* / Q000601:surgery; D015948:Keratoplasty, Penetrating; D008297:Male; D008826:Microbial Sensitivity Tests; D008828:Microbiological Techniques; D017422:Sequence Analysis, DNA; D055454:Trametes / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D065819:Voriconazole / Q000494:pharmacology
D000935:Antifungal Agents; D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D065819:Voriconazole
Basidiomycete; Cornea; Fungus; Keratitis; Lenzites betulina; Trametes betulina