HPV Infection Sites: Skin, Anogenital, Oropharyngeal & Respiratory Tracts

Human Papillomavirus (HPV) Tropism

HPV infects stratified squamous epithelium. >200 genotypes; ~40 mucosal types. Tissue specificity varies by genotype.

Major Anatomic Sites & Clinical Sequelae

Site	HPV Types	Manifestations
Cutaneous Skin	1, 2, 4, 27, 57 (cutaneous)	Common warts (hands), plantar warts (feet), flat warts (face/legs)
Anogenital	6, 11 (low-risk); 16, 18, 31, 33, 45, 52, 58 (high-risk)	Genital warts (condyloma), cervical/vulvar/vaginal/penile/anal intraepithelial neoplasia & cancer
Cervix	16, 18 (70% cervical CA)	CIN 1/2/3 → invasive carcinoma. Screening: Pap + HPV co-test.
Oropharynx	16 (90% HPV+ OPSCC)	Tonsillar/base of tongue cancer. Rising incidence (males). No screening test.
Respiratory Tract	6, 11 (rare)	Recurrent respiratory papillomatosis (RRP) – laryngeal warts, airway obstruction. Juvenile/adult onset.
Conjunctiva	Rare	Conjunctival papilloma/carcinoma.

Key Points

• High-risk types integrate into host DNA → E6/E7 oncoproteins degrade p53/pRb → carcinogenesis.
• Most infections clear spontaneously (1–2 years). Persistence → neoplasia.
• 9-valent vaccine (Gardasil 9) covers 6, 11, 16, 18, 31, 33, 45, 52, 58. Best before sexual debut.
• No treatment for virus itself; treat lesions (ablation, excision, topicals).