Review Question - QID 104270

This patient is suffering from herpes zoster (shingles). The first-line treatment for shingles is acyclovir (or other similar antivirals such as valacyclovir or famciclovir), which reduces the duration of the disease and the incidence of postherpetic neuralgia.

Shingles is due to reactivation of varicella zoster virus in the dorsal root ganglia that leads to eruption of a painful rash in a dermatomal distribution. Postherpetic neuralgia is the most common complication of the disease and is due to viral destruction/damage of nerves that leads to dermatomal pain and allodynia. It is more common in the elderly and women. Postherpetic neuralgia may last from 30 days to 6 months after resolution of the skin lesions. The varicella zoster vaccine is effective at preventing shingles outbreaks, and adults 60 years of age and older should receive the vaccine regardless of whether or not they have had a prior episode of shingles. An immunocompromising condition or history of severe reaction to a vaccine component are contraindications to administration.

Figure A shows the characteristic rash of shingles; note the dermatomal distribution that does not cross the mid-line.

Incorrect Answers:
Answer 1: Antivirals inhibit viral replication and shedding, therefore decreasing the likelihood of transmission of the disease to another host.
Answer 3: Antiviral agents such as acyclovir exert a direct antiviral effect on the varicella zoster virus that does not depend on the strength of the host's immune system. In fact, acyclovir is also indicated for treatment of shingles in immunocompromised patients.
Answer 4: Acyclovir can decrease the incidence of postherpetic neuralgia if administered early but would not increase the risk.
Answer 5: Antivirals should be initiated as soon as possible, as these medications have been shown to be most effective when started within 72 hours of rash eruption.