A 28-year-old woman presents with multiple painful lesions on her vulva and perianal region for 3 weeks. She reports severe pain during micturition and defecation. On examination, she has grouped vesicles on an erythematous base, along with several flesh-coloured, dome-shaped papules with a rough surface on the labia majora and perianal skin. She is sexually active with a new partner 2 months ago. What is the most likely diagnosis of the dome-shaped papules?

Explanation

## Clinical Presentation Analysis The patient presents with two distinct lesions: 1. **Grouped vesicles on erythematous base** → consistent with HSV-2 (primary genital herpes) 2. **Flesh-coloured, dome-shaped papules with rough surface** → consistent with **condyloma acuminatum (genital warts)** ### HPV-Associated Genital Warts **Key Point:** Condyloma acuminatum is caused by low-risk HPV types, predominantly HPV-6 and HPV-11 (responsible for ~90% of genital warts). These are non-oncogenic types. **High-Yield:** The morphology of genital warts is pathognomonic: - Flesh-coloured or slightly pigmented - Dome-shaped or papillomatous - Rough, keratotic surface ("cauliflower-like" when large) - May be solitary or clustered - Typically painless (unless traumatized or secondarily infected) ### Differential Features | Feature | Condyloma Acuminatum | Molluscum Contagiosum | Lichen Planus | HSV | |---------|----------------------|----------------------|---------------|-----| | **Shape** | Dome-shaped, papillomatous | Umbilicated dome | Flat-topped polygonal | Vesicular | | **Surface** | Rough, keratotic | Smooth with central dimple | Shiny, polygonal | Vesicles → erosions | | **Colour** | Flesh-coloured | Flesh-coloured/pearly | Violaceous | Erythematous | | **Pain** | Usually painless | Painless | Pruritic/painful | Painful | | **Causative agent** | HPV-6, HPV-11 (low-risk) | Poxvirus | Autoimmune (T-cell) | HSV-1/2 | ### Clinical Pearl **Coinfection with HSV-2 and HPV is common in sexually active individuals.** The presence of both vesicular lesions (HSV) and papillomatous lesions (HPV warts) in the same anatomical region is not uncommon and requires recognition of both entities for appropriate management. ### HPV Typing and Oncogenic Risk **Mnemonic: "Low-risk HPV = 6, 11 (genital warts); High-risk HPV = 16, 18 (cervical cancer)"** - **Low-risk types (6, 11):** Cause genital warts; <1% malignant potential - **High-risk types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68):** Associated with cervical, anal, oropharyngeal, and other anogenital cancers **High-Yield:** HPV-16 and HPV-18 account for ~70% of cervical cancers. HPV-16 alone is responsible for ~50% of cervical cancers. ### Management Approach 1. **Confirm diagnosis:** Clinical (morphology) or dermoscopy; HPV typing not routinely done for genital warts 2. **Treat HSV infection:** Acyclovir 400 mg TDS for 7–10 days (primary infection) or valacyclovir 3. **Manage genital warts:** - Topical: Podophyllotoxin 0.5% (patient-applied), imiquimod 5% cream, sinecatechins - Destructive: Cryotherapy, electrocautery, laser ablation - Surgical: Excision for large lesions 4. **Cervical screening:** Recommend Pap smear or HPV testing for all women with genital warts (even though HPV-6/11 are low-risk, concurrent high-risk HPV may be present) 5. **Vaccination:** HPV vaccine (9-valent preferred) can be offered if not previously vaccinated [cite:Fitzpatrick's Dermatology 9e Ch 28]