xCORRECT ANSWER: B
This patient's clinical syndrome strongly suggests genitalherpes. Genital herpes is caused by either herpessimplex virus type 1 (HSV-1) or herpes simplex virustype (HSV-2). The former is less common (20% of clinicalcases of genital herpes) and is transmitted by oralgenitalcontact; the latter is more common and is transmittedby genital contact with an infected partner who isshedding virus.1The clinical features seen here suggest initial infection,which begins with macules and papules that developinto vesicles,pustules, and ulcers--and thenheal (Figure).The constitutionalsymptoms oflow-grade fever,headache, andmalaise aremore commonlyseen in women.The entire clinicalsyndromepeaks afterabout 1 weekand resolves byweek 2.2 The naturalhistory of genitalherpes is recurrentinfection,which canbe asymptomaticor symptomatic.The 1-year recurrencerate is90%; 20% of infected patients have more than 10 recurrencesin a year.3 Viral shedding occurs during these recurrences,and patients can transmit disease whether ornot the recurrences are symptomatic.Thus, the goals of therapy are to:
Of the therapies offered here, valacyclovir (choice
) is indicated for this patient. Acyclovir and famciclovirare also effective but vary in their dosing, convenience,and cost.Once material from the lesions has been sent forculture for HSV, begin treatment without waiting for theresults. Most authorities recommend that long-termsuppressive therapy be started after the initial infectionrather than in response to each recurrence. Such longtermsuppressive therapy (eg, valacyclovir, 500 mg/d)has been shown to be safe and to reduce the number ofrecurrences, the viral shedding, and the risk of transmissionto partners.
Benzathine penicillin G, 2.4 million U IM (choiceA), is the classic regimen for syphilis, which is clearly inthe differential of labial lesions. However, the chancre ofprimary syphilis--a painless, usually solitary, induratedlesion--does not correspond to the physical findings inthis woman. Because patients with sexually transmitted