Let’s go back on the clinical side of the fence this month. There I was, getting ready to present a lecture on herpetic disease at a state society meeting. One association officer leaned over to another and said, “Who’s speaking?” The other guy said, “Oh, Bill’s got herpes.” Everybody within earshot laughed. Yes, I guess I do, as I had chickenpox as a kid, and something like 95% of us humans carries herpes simplex. But, that’s not what any of this is about.
Is there an infectious disease diagnosis that strikes more fear than the consideration of ocular herpetic disease?
Even after 36 years of practice, I still cringe at the spectrum of signs and symptoms that present in simplex or zoster. I’ve seen more pain and vision loss with these two compadres than with any other type of infection. That includes microbial keratitis and EKC.
Our antiviral agents are far from instantly effective, though much improved over those of three decades ago. Let’s talk about the best use of these agents, for both simplex and zoster. Yes, there are other herpes viruses that cause ocular manifestation, including Kaposi’s sarcoma and chronic fatigue syndrome. We’ll exclude those for the purposes of this article.
Oral meds have come to the forefront for zoster as well as simplex.
You’ve got to get your “orals” on board for the effective treatment of herpetic disease. It’s that simple. The HEDS study of two decades ago indicated the importance of oral antiviral dosing in the prevention of complications and future episodes of herpes simplex keratitis. (Footnote 1) Further back, studies showed that oral antivirals attained therapeutic levels of acyclovir in the TEAR FILM with standard dosage. (Footnote 2)
Currently, university centers like New York University are working on the Zoster Eye Disease Study (ZEDS) study in order to determine the effectiveness of acyclovir in limiting the ocular complications and post-herpetic neuralgia in “shingles” patients. It turns out that our cornea specialist has been dosing post-ZOSTER patients with low dose Valtrex for his entire 35-year career. He believes, as do founders of the ZEDS study, that Herpes Zoster infections are far from eliminated by the PDR’s indication of “1000 mg Valtrex t.i.d. for one week.” I’d say that he’s spot-on, as the keratitis, uveitis, and post-herpetic neuralgia have been horrible consequences in our practice. He has the post-herpes zoster ophthalmicus patient on this oral “suppression” dosing for at least one month, and usually longer.
Let’s draw a parallel between long term simplex treatment, versus zoster.
If you believe that viral suppression is important, per the HEDS study, why would zoster be any different? The two viruses are really close cousins. Classic teaching indicates that post-zoster problems are INFLAMMATORY and not infectious, but the chronic INFECTION aspect of zoster is creeping into the literature. Some authors have suggested that we treat herpes zoster keratitis with topical Zirgan as well as oral meds. (Footnote 3) Does the zoster pseudodendrite have an infectious aspect? It may be worth treating topically as well as systemically.
Your work isn’t done when the shingles vesicles have resolved.
Aside from vesicular eruptions that go on and on, the ensuing weeks often produce post-herpetic neuralgia. Horrible pain is usually the result, limiting the patient’s productivity and enjoyment of life. How about direct ocular effects after a bout of shingles? I can’t tell you how many times I have had a patient return “a month or two later” for a routine exam, and found low-grade anterior chamber cells, granulomatous keratic precipitates, elevated intraocular pressure, and an unhappy patient. Will our oral antiviral prophylaxis help? We think so, but we need the ZEDS study to elaborate. Otherwise, it’s unsubstantiated. In the meantime, consider the relatively safe administration of Valtrex, 500 mg by mouth on a daily basis for at least a month or more after shingles have “resolved.”
Let’s have just a word on vaccinations. We do a wonderful public health service for our patients when we advocate for herpes zoster immunization. The new two-step Shingrix vaccine for zoster is more effective than its predecessor Zostavax, and can save our patients from the chronic pain that this infection can bring. (Footnote 4)
All told, we need to keep a sharp edge of knowledge and treatment of our patients suffering from the herpes viruses. Follow the results of the ZEDS study in the coming years!!