Observational case report.
RESULTS:
Penetrating keratoplasty was performed in the left eye with a history of
herpetic keratitis that resolved with periodic treatment with ACV
ointment and a topical
steroid. The left eye was painful and red with an
abscess and corneal erosion in the peripheral donor cornea. Examination of the scraped corneal epithelium by light microscopy and culturing identified Candida albicans; polymerase chain reaction (PCR) was negative for human herpes viruses. After antifungal treatment, the ocular
pain gradually decreased and the lesions slowly improved but recurred with a similar clinical appearance. A second light microscopy examination and cultures were negative for pathogens including C. albicans. PCR was positive for HSV-1
DNA; treatment with 3% topical ACV
ointment was unsuccessful. A third examination showed only HSV-1
DNA. Despite
antiviral ACV
ointment, no clinical improvement occurred based on the HSV
DNA copy numbers, which were the same before and
after treatment, indicating a possible ACV-resistant strain. When topical
trifluorothymidine was substituted for ACV, clinical improvement occurred and the HSV
DNA copy numbers decreased.
CONCLUSION: Necrotizing
keratitis induced by ACV-resistant HSV occurred independently after fungal
keratitis, with a similar clinical appearance in this case, making diagnosis and treatment difficult. Monitoring the HSV
DNA load by real-time PCR could be useful for refractory cases even with atypical clinical appearances.