Fungal keratitis caused by Chaetomium atrobrunneum.

Purpose: We report a case of mycotic keratitis caused by a rare fungus Chaetomium atrobrunneum.

Methods: Clinical examination, slit-lamp examination, and microbiological evaluation of corneal ulcer were done, and its treatment outcome was studied. The fungal etiology was established by conventional microbiological techniques: polymerase chain reaction and speciation by DNA sequencing.

Results: Based on morphological features of the isolate and DNA sequence analysis of the internal transcribed spacer region, the isolate was identified as C. atrobrunneum. The keratitis was resolved completely by topical natamycin and oral ketoconazole.

Conclusion: To best of our knowledge, this is the first reported case of keratitis caused by a rare fungus, C. atrobrunneum, which was successfully treated with dual therapy.