Objective: To study the correlation of clinical findings, histopathologic features, and detection of varicella-zoster virus (VZV) DNA in keratectomy specimens.
Materials and methods: Fourteen corneal buttons from patients with a confirmed history of herpes zoster ophthalmicus were examined by use of light microscopy and the polymerase chain reaction. The polymerase chain reaction techniques included gel electrophoresis and hybridization for the detection of VZV DNA.
Results: Seven (50%) of the 14 specimens were positive for VZV DNA. The positive findings in the specimens correlated with the clinical findings of uveitis (3/3) and the histopathologic features of chronic stromal keratitis (4/4). Patients with stromal scarring, granulomatous keratitis, and neurotrophic ulcers had negative findings. The largest interval between the initial appearance and detection of viral DNA was 51 years.
Conclusions: The results suggest that VZV DNA is not detectable in the cornea in every patient and at every stage of zoster keratitis. This may be due to the low number of VZV particles present in the cornea or the lack of viral DNA in the keratocytes. It remains unclear whether the VZV-related keratopathy is caused by an immunologic response to a viral antigen, the viable virus itself, or both.