Delayed herpes zoster pseudodendrites. Polymerase chain reaction detection of viral DNA and a role for antiviral therapy
D. Pavan-Langston, S. Yamamoto and E. C. Dunkel
Department of Ophthalmology, Harvard Medical School, Boston, Mass, USA.
BACKGROUND: The late-onset pseudodendrites, delayed corneal mucous plaques,
of herpes zoster ophthalmicus are reported to be of mechanical or immune
origin and to be worsened by antiviral therapy. OBJECTIVE: To study
pseudodendrites to ascertain a viral presence in the lesions and their
response to antiviral therapy. DESIGN: Prospective clinical study. SETTING:
Outpatient and inpatient hospital-based corneal specialty referral
practice; molecular virology laboratory. PATIENTS: Six patients, aged 33 to
89 years, four with delayed herpes zoster ophthalmicus pseudodendrites and
two with herpes zoster ophthalmicus neurotrophic ulceration. One patient
was immunosuppressed. MAIN OUTCOME MEASURES: Findings from clinical
evaluation; polymerase chain reaction assays of lesions and tear film of
six patients; polymerase chain reaction and light and electron microscopy
of the corneal button from one patient; and the clinical response of four
patients to various antiviral drugs. RESULTS: In contrast to reports in the
current literature, delayed pseudodendrites may also be infectious, as they
are positive for zoster DNA by polymerase chain reaction and appear
responsive to certain antiviral therapy. The corneal button from an
immunosuppressed patient had mature and immature viral particles in the
basal cells within 2 weeks of transplantation. CONCLUSIONS: To our
knowledge, this is the first report of viral DNA in delayed zoster
pseudodendrites. Recurrent viral infection may play a role in this form of
zoster keratopathy and warrant antiviral therapy.
