A rare case of mixed infectious keratitis caused by Pseudomonas koreensis and Aspergillus fumigatus

We report the clinical and microbiological features of contact lens-related mixed infectious keratitis caused by a spore-forming filamentous fungus and a rare gram-negative bacterial infection. A 66-year-old Caucasian female presented with right eye (OD) pain after sleeping in her 2-weekly contact lenses for 3 days. On presentation, corrected distance visual acuity was 0.46 LogMAR OD and 0.20 in the left eye. Slit lamp biomicroscopy revealed a 1.9 mm by 1.9 mm area of dense stromal infiltrate with epithelial defect. Corneal scrapes grew Aspergillus fumigatus and Pseudomonas koreensis, and culture-directed microbial therapy with oral and topical voriconazole and topical fortified gentamicin along with regular debridement resulted in slow resolution of the infection, leaving a dense stromal scar in the visual axis requiring penetrating keratoplasty. Mixed infectious keratitis caused by filamentous fungi and gram-negative bacteria is rare. Pseudomonas koreensis infection has not been previously reported as a cause of infectious keratitis in humans. In our experience, these mixed infections require prolonged systemic and topical therapy and the secondary scarring may require surgical intervention for vision rehabilitation.