Which of the following is the causative organism of vulval warts?

Correct Answer: C. Human papilloma virus

Vulval warts are benign epithelial proliferations caused by Human Papillomavirus (HPV), specifically non-oncogenic types (HPV-6, HPV-11) that produce visible condylomata acuminata. HPV is a DNA virus transmitted sexually and causes productive infection in the basal epithelium, leading to hyperkeratosis and acanthosis. The virus replicates in the upper epithelial layers, producing the characteristic "cauliflower-like" appearance. In India, HPV-related vulval warts are increasingly common in sexually active women; they are benign but cosmetically distressing and require treatment (topical imiquimod, podophyllin, cryotherapy, or surgical excision). Importantly, while HPV-16 and HPV-18 (oncogenic types) carry malignant potential and are targets of vaccination (Gardasil, Cervarix), the visible warts themselves are usually caused by low-risk types. The diagnosis is clinical; histology shows koilocytosis (perinuclear halos) and hyperkeratosis. HPV testing and cervical screening remain essential in women with vulval warts because of the increased risk of cervical dysplasia.

Why the other options are wrong

A. Herpes simplex virus — HSV causes painful vesicles and ulcers on the vulva (herpes genitalis), not warts. HSV lesions are acute, recurrent, and painful with clear fluid; they heal with crusting. NBE may trap students who confuse 'vulval lesions' broadly—but HSV never produces the chronic, hyperkeratotic, pedunculated warts characteristic of HPV infection. B. Cytomegalovirus — CMV causes systemic infection primarily in immunocompromised hosts (CD4 <50 in AIDS) and presents with retinitis, colitis, or esophagitis—not vulval warts. CMV is not sexually transmitted in the way HPV is, and vulval CMV disease is exceptionally rare. This is a distractor for students unfamiliar with CMV's true clinical spectrum. D. Human immunodeficiency virus — HIV is the causative agent of AIDS and does not directly cause vulval warts; however, HIV-positive women have increased incidence and severity of HPV-related warts due to immunosuppression. NBE may trap students who conflate 'HIV increases wart risk' with 'HIV causes warts'—a common misconception in Indian medical education.

High-Yield Facts

Mnemonics

HPV Warts vs. HSV Ulcers Warts = Warts (HPV, warty, chronic); Ulcers = Ulcers (HSV, ulcerated, acute painful). Use this when a question mentions 'vulval lesions'—warts = HPV, ulcers/vesicles = HSV. HPV Types: 6, 11 (Low-Risk) vs. 16, 18 (High-Risk) 6, 11 = Benign Warts; 16, 18 = Cancer Risk. Low numbers = low risk (visible warts); high numbers = high risk (dysplasia/cancer). Vaccine covers all four.

NBE Trap

NBE pairs HIV with vulval warts to trap students who conflate 'increased HPV disease in HIV-positive women' with 'HIV causes warts.' The correct answer is HPV; HIV is a risk factor, not the causative organism.

Clinical Pearl

In Indian clinical practice, HPV-related vulval warts are increasingly seen in young sexually active women; always screen for cervical dysplasia (Pap smear or HPV testing) because vulval warts signal HPV exposure and increased cervical cancer risk. Vaccination of adolescent girls (IAP guideline) is the most cost-effective prevention strategy in India.

_Reference: DC Dutta's Textbook of Gynaecology (7th ed.), Ch. 12 (Benign Lesions of Vulva); Harrison's Principles of Internal Medicine, Ch. 226 (Papillomavirus Infections)_