Ins & Outs of Zoster

Ins & Outs of Zoster

Description & Etiology:

Millions of children (and adults) in the United States suffer from the chickenpox each year, which is caused by the Herpes virus, varicella. Little do they know that that this virus may come back to haunt them in the way of varicella zoster virus (VZV); the infection also commonly known as Shingles. Herpes zoster or shingles is a reactivation of varicella virus that otherwise stays dormant in a nerve root ganglia. This can happen in either a dorsal-nerve root or cranial-nerve root and gets reactivated by some trigger. The precise triggers for reactivation remain unknown but they are thought to be associated with genetics, increased age, stress, immunosuppression, and potentially environmental changes.

So who gets it? According to the CDC, nearly one in about three people will develop Shingles in their lifetime within the United States, with about one million people being affected annually. Anyone who underwent getting a chickenpox vaccine or suffered from chickenpox may develop Shingles. People in the age range of 50-70 get it more often than the others. In regards to transmission, it cannot be transmitted by sneezing/coughing, however Shingles can be transmitted by direct contact during the time that the rash reveals blisters.

Signs/Symptoms:

The majority of patients initially complain of skin sensation changes in the way of paresthesias that progress to pain. This pain is localized along one dermatome and is typically described as sharp/stabbing, non-radiating, non-exertional, waxing and waning in severity, and without significant alleviating/aggravating factors despite patients commonly attempting OTC analgesia. A lot of the time, this occurs on the trunk though we see it about the face as well. After a few days, a lot of patients will feel generally ill, may even have a fever, and will develop a rash. This rash usually sets up around day three or four and consists of very painful vesicles upon a broad erythematous base. These vesicles can open and (though uncommon in an otherwise healthy patient), potentially lead to cellulitis. After about day five or six this rash will tend to crust over though there may still be considerable pain.

Occasionally the eruption will occur about a facial nerve distribution. There are a few things that have to be carefully addressed or ruled out when a patient has Shingles about his/her face. First, we must establish the presence of ocular herpes. We do this by placing fluorescein dye in the eye and performing an examination using a Wood’s or slit lamp to look for dendritic lesions. Another thing to look for is Hutchinson’s sign, which is when the tip of the nose is painful or rash laden 2 to a Zoster infection of the nasociliary branch of CN V1. This may indicate ocular involvement.

Diagnostics & Treatment:

The bulk of Shingles cases can be diagnosed clinically based on an accurate H & P without any sort of formal testing. That said, in cases where the evidence is not as clear there are several other tests that can paint a better picture or help confirm diagnosis. There is serologic testing that can identify IgM/IgG associated with varicella. Tzanck smear is a cost effective way to identify Shingles. Other tests include PCR and direct fluorescent antibody staining. Again, these are nearly always unnecessary as this disease process presents itself quite well.

As far as treatment is concerned, first line therapy involves antivirals - Acyclovir 800 mg PO 5x daily for 7 days is fairly common practice. Additionally, analgesics (often in the form of narcotics) are normally prescribed as well. In my practice, I commonly will prescribe oxycodone IR 5 mg PO q 4-6 hrs PRN. I do this instead of percocet, as the patient may unknowingly take acetaminophen on their own, and I do not want to run the risk of hepatic injury. The use of corticosteroids for acute Shingles flare is controversial.

The last treatment is actually “pre-treatment” – vaccination. CDC recommends that people over the age of 60 years of age receive the Shingles vaccination unless the patient is immunocompromised, pregnant, has ever had a life-threatening or severe allergic reaction to gelatin, the antibiotic neomycin, or any other component of shingles vaccine.

Complications:

Postherpetic neuralgia (PHN) is the most common complication of herpes Zoster. It is a situation by which there is still significant pain even after the rash has resolved. This can be persistent for several years in some patients. Another complication as above is cellulitis. Since there is an opening in the skin, there is a greater risk of suffering an infection in this area. This might lead to an interesting situation during which a patient is on an antiviral and an antibiotic at the same time. Other complications associated with Shingles’ are encephalitis, pneumonia, blindness, and death, though these are quite uncommon.

Author:

Nathan Cameron, MPAS, PA-C served as a medic in the United States Air Force before attending undergrad at Metropolitan State University of Denver in Biology. While getting his undergrad, he was a paramedic for the Denver Paramedic Division. He left the paramedic life to return to school full time. He has since graduated from the PA Program at Red Rocks Community College in Colorado, and has received his Masters of Medical Science from St. Francis University, Pennsylvania. After graduation he immediately went into orthopedic surgery and emergency medicine, though now he is practicing emergency medicine full time. When not working in the ER, he enjoys spending time with his wife and four children, as well as playing golf…or trying to at least.


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