Unusual Presentation of Pythium Keratitis as Peripheral Ulcerative Keratitis: Clinical Dilemma

To describe the clinical picture and outcome of a case of Pythium keratitis, presenting as peripheral ulcerative keratitis (PUK).

A 54- year- old male presented to the clinic with a PUK in the right eye. Systemic investigations were performed to rule out associated collagen vascular disorders. Microbiological examination of corneal scrapings was performed to rule out secondary infection which revealed gram positive cocci on Gram stain. There was no growth of any organism on culture. Topical vancomycin 5% and ciprofloxacin 0.3% were started initially. On regular follow-up, there was worsening of clinical signs. Topical and oral corticosteroids were further added. Due to progressive worsening of infiltrate size and corneal perforation, therapeutic penetrating keratoplasty was performed. Pythium insidiosum (confirmed by DNA sequencing and zoospore formation) was grown from excised corneal button and the histopathology revealed filaments suggestive of Pythium species.

This case describes the uncommon manifestation of Pythium insidiosum keratitis presenting as peripheral ulcerative keratitis.