Can Herpes Simplex Virus 1 (HSV1) present with vulvar ulcerations in a sexually active 18-year-old female?

Can HSV-1 Present with Vulvar Ulcerations in a Sexually Active 18-Year-Old Female?

Yes, HSV-1 absolutely can present with vulvar ulcerations in a sexually active 18-year-old female, and this presentation is increasingly common, accounting for up to 50% of primary genital herpes cases in recent years. 1, 2

Clinical Presentation of Genital HSV-1

The classic presentation involves vesicles that burst to form shallow ulcers or erosions on the genitals, buttocks, or thighs. 3 The clinical features include:

• Vesicular and/or ulcerative lesions specifically on the vulva, labia, and surrounding genital area 3
• Vesicles contain clear fluid with high concentrations of infectious viral particles 3
• Lesions progress from papules to vesicles, then burst forming shallow ulcers that eventually crust and heal without scarring 3
• Episodes typically last less than 10 days, though may be prolonged with secondary bacterial infection 3
• Incubation period ranges from 2-10 days (up to 4 weeks) 3

Why HSV-1 Genital Infections Are Increasingly Common

A rising proportion of genital herpes is now attributable to primary HSV-1 infection, transmitted through oral-genital sexual contact. 2 This shift reflects:

• Increased sexual promiscuity and more advanced sexual techniques contributing to genital HSV-1 transmission 2
• Up to 50% of incident genital herpes episodes are now caused by HSV-1 rather than HSV-2 1
• Genital HSV-1 infections are usually less severe clinically and less prone to recurrence compared to HSV-2 2

Critical Diagnostic Approach

Laboratory confirmation should always be sought because clinical diagnosis alone is often inaccurate. 3 The recommended diagnostic workup includes:

• HSV culture or antigen test from the ulcer base or vesicular fluid 3
• PCR testing from lesions (gold standard) 4
• Serologic test for syphilis (to exclude co-infection) 3
• Testing for other STIs including Chlamydia trachomatis and Neisseria gonorrhoeae 3

Collection technique matters: Open vesicles with a sterile needle, collect vesicular fluid with a swab for viral culture or nucleic acid amplification tests 3

Important Clinical Pitfalls

Do not rely on clinical appearance alone—HSV is the most common cause of sexually acquired genital ulceration, but other etiologies must be excluded. 3 Key considerations:

• Co-infections occur: Up to 10% of patients with genital ulcers may have HSV co-infected with Treponema pallidum 3
• Non-infectious causes can mimic HSV, including Behçet syndrome, Crohn disease, and fixed drug eruption 3
• Atypical presentations can include nonhealing ulcers, fissures, or localized erythema 4
• Even after complete diagnostic evaluation, 25% of genital ulcers have no laboratory-confirmed diagnosis 3

Serious Complications to Monitor

While rare, primary genital HSV-1 can lead to life-threatening complications, particularly in this age group. 1 Be vigilant for:

• Sepsis secondary to bacterial superinfection (documented with Streptococcus pyogenes bacteremia in an 18-year-old) 1
• Urinary retention requiring catheterization 4
• Rapid progression to necrosis (documented within 48 hours in severe cases) 4
• Systemic complications including aseptic meningitis, hepatitis, and sacral radiculitis 1

If fever develops or lesions progress rapidly, consider secondary bacterial infection and initiate systemic antibiotics in addition to antiviral therapy. 4

Management Implications

Antiviral therapy should be initiated within 72 hours of symptom onset and continued for 7-10 days. 4 For this sexually active 18-year-old:

• Acyclovir is the standard treatment 5
• Symptomatic relief with topical lidocaine gel may be necessary 5, 4
• Urinary catheterization may be required if dysuria is severe 4
• Debridement is only necessary if necrotic tissue develops and lesions are not healing 4

Differential Diagnosis Considerations

In a sexually active 18-year-old with vulvar ulcerations, also consider:

• Syphilis (Treponema pallidum) - requires darkfield examination or serology 3
• Chancroid (Haemophilus ducreyi) - though less common in most U.S. areas 3
• Non-sexually transmitted causes in rare cases, including ulcus vulvae acutum associated with influenza infection 5, 6

The key distinguishing feature is that HSV testing (culture or PCR) will be positive, whereas these other conditions will have negative HSV results. 5, 4