A 31-year-old woman presents for evaluation of hair thinning. An incidental finding during examination is an erythematous patch with vesiculation under her lip. This appeared 2 days earlier and is somewhat painful. She had one similar eruption as a child. Her medical history is significant for Hashimoto thyroiditis.
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Herpes simplex virus (HSV) infection involves a double-stranded DNA virus that resides within nerve ganglia. Two types of these viruses infect humans: HSV1 and HSV2, both of which are spread by direct contact.
HSV1 is usually first acquired in infancy or early childhood, whereas HSV2 is spread by sexual contact during adolescence or adulthood.1 Common areas of HSV involvement are the oral mucosa and genitalia. Oral disease is most commonly caused by HSV1, and genital disease is most often caused by HSV2. A significant percentage of the population have been exposed to HSV1.2
Oral HSV, commonly referred to as a fever blister or cold sore, is often preceded by localized tingling or pain. Shortly thereafter, tiny vesicles arise that crust over and then resolve. Recurrences are usually infrequent, although some individuals may experience multiple episodes each year.3 Drugs approved to both treat HSV infection and prevent recurrence are acyclovir, valacyclovir, and famciclovir.4
Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. He practices dermatology in Hazleton, Pennsylvania.
- Johnston C, Morrow RA, Stanberry LR. Human herpesviruses: herpes simplex virus types 1 and 2. In: Kaslow RA, Stanberry LR, Le Duc JW, eds. Viral Infections of Humans: Epidemiology and Control. New York, NY: Springer US; 2014:829-854.
- Bernstein DI, Bellamy AR, Hook EW 3rd, et al. Epidemiology, clinical presentation, and antibody response to primary infection with herpes simplex virus type 1 and type 2 in young women. Clin Infect Dis. 2013;56:344-351.
- Spruance SL, Overall JC Jr, Kern ER, Krueger GG, Pliam V, Miller W. The natural history of recurrent herpes simplex labialis: implications for antiviral therapy. N Engl J Med. 1977;297:69-75.
- Antiviral drugs. Treatment Guidelines from the Medical Letter. 2013;11:19-30.