Detection of varicella-zoster virus DNA in keratectomy specimens by use of the polymerase chain reaction
H. Mietz, A. M. Eis-Hubinger, R. Sundmacher and R. L. Font
Department of Ophthalmology, Baylor College of Medicine, Houston, Tex, USA. h.mietz@uni-koeln.de
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.
