EM:RAP Emergency Medicine: Reviews and Perspectives

2012  ›  November Episode

Dirty Nasty Bits: Zoster

EMRAP and infectious disease. Two peas in a pod? Not lately. We embark on a series of segments to change that. Zoster is up first.

 

Contributors

  • Sukhjit "Sarge" Takhar, MD
  • Mel Herbert, MD MBBS FAAEM

Comments on Dirty Nasty Bits: Zoster

Abdullah Al-Somali

Amazing segment :) Thank you.... took a lot of confusion away really.

Paul B., M.D.

Great tidbits!

Mel H.

Question from Val Norton, do you use steroids in ZOSTER?

Answer from SARGE:
There is some evidence that shows corticosteroids may help with acute pain -- but not with post herpetic neuralgia. The two biggest, and most cited, studies were done in the mid 90’s. They both showed that corticosteroids are not helpful in preventing post herpetic neuralgia.
Wood, Martin J., et al. "A randomized trial of acyclovir for 7 days or 21 days with and without prednisolone for treatment of acute herpes zoster." New England Journal of Medicine 330.13 (1994): 896-900.
Whitley, Richard J., et al. "Acyclovir with and without prednisone for the treatment of herpes zoster. A randomized, placebo-controlled trial. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group."Annals of internal medicine 125.5 (1996): 376.
In the Wood paper, they excluded patients with hypertension, PUD, insulin-dependent diabetes, and patients with renal failure. In the Whitley paper, they exluded patients who required immunosuppressive therapy, hypertensive patients, osteoporosis, and a couple of other things. Generally, it is thought that steroids can probably decrease the amount of acute pain. But the side effect profile isn’t great and steroids do not decrease the rate of post herpetic neuralgia. Risk factors for PHN are the following: Older age, greater severity of rash, greater acute pain intensity.
Clinical infectious disease put together evidence based recommendations for Herpes Zoster in 2007
Dworkin, Robert H., et al. "Recommendations for the management of herpes zoster." Clinical Infectious Diseases 44.Supplement 1 (2007): S1-S26.

I’ve found that really smart people confuse steroids in Bell’s palsy – where it is probably helpful and in Zoster – where it probably doesn’t help.
Hope this answers those questions. Let me know if there were other areas in my presentation that also weren’t clear.
Thanks,
Sarge

Ricky G

Is the 72 hour window for antiviral treatment of uncomplicated truncal zoster in immunocompetent patients from the onset of symptoms (pain) or the onset of the rash?

Sarge

Interesting question... Certainly pain can start before the rash. Sometimes there might not even be a rash.

Technical details:
Patients who had a rash for more than 72 hours were excluded from some of the bigger studies on zoster and antiviral therapy.

Fine points:
However, those with severe disease who have new lesions that have cropped up may benefit from therapy.

Deniz T., M.D.

Thank you for the fine segment.

Question for Mel or Sarge: If Zoster is a reactivation of varicella virus which stays in dorsal root ganglia for life, why is a vaccine effective? What does the vaccine do, other than present the immune system with antigenic material .. which is already in there, by definition?

Thanks and best regards
Deniz Tek

Sarge

Hi Deniz,
Thanks for the question. Yes -- Herpes Zoster does lay dormant in the dorsal root ganglia. The cell mediated arm of the immune system is our primary defense against reactivation. But over the years, the immune system may have forgot about the latent virus -- there probably isn’t enough of VZV antigen circulating for the body to “remember.” The cell mediated immune system is affected by multiple medications, such as steroids, and natural processes, such as aging. The vaccine simply presents the immune system with boost, helping keep that dirty little virus confined to the dorsal root ganglia, where it belongs.
Hope that helps and thanks for listening,
Sarge

You must login or subscribe to comment on this segment.