Though much is occurring in the diagnosis and treatment of viral eye infections, much of it may be under the radar for ophthalmologists. Variability in disease presentation and host immunity--relatively recent observations--are important factors, according to Todd P. Margolis, MD, PhD.
Ophthalmologists are perhaps not as aware of these diseases as they should be, and because of this, they can go unrecognized in the clinic, explained Dr. Margolis, the Alan A. and Edith L. Wolff Distinguished Professor and chairman, Department of Ophthalmology and Visual Science, Washington University, St. Louis.
Varicella zoster virus (VZV)
The incidence and prevalence of chronic and recurrent ocular VZV are unknown, and evaluating referral patients in practice makes it hard to ascertain the actual demographics, Dr. Margolis noted.
“Mucous plaque keratopathy--an infectious epithelial keratitis--is found in up to 13% of patients with ocular zoster and can occur years after the initial disease,” he said. “Recurrent iritis and uveitis have been documented in 7.4%, and recurrent keratitis is diagnosed in 6.9%.”
The percentage of ocular zoster patients with such complications may be higher, he noted.
“Physicians should keep in mind that more antiviral drugs and fewer corticosteroids are needed, in my experience,” Dr. Margolis said. “Patients are referred because of inflammation and are taking more steroids because physicians overlook the infectious component. When I decrease corticosteroids and increase antiviral drugs, patients tend to improve.”
Zoster sine herpete
The degree of skin eruption varies from easily missed lesions to extensive skin eruptions based on the affected structures.
When all the branches of the first division of the fifth cranial nerve are involved, very extensive involvement of the skin and eyes may develop. However, if only a single twig of the nasociliary branch of the first division of the trigeminal nerve is involved, there may be ocular involvement (cornea and/or iritis) in the absence of skin eruption (zoster sine herpete), Dr. Margolis noted.