Pubic Lice (Pediculosis Pubis)
🪒 Shaving the pubic area is not necessary. Interestingly, the incidence of pubic lice has been declining in the general population due to widespread pubic hair removal, which destroys the parasite’s natural habitat.
📌 About
- Infestation with pubic lice (Phthirus pubis) is an STI-associated ectoparasite and may coexist with other sexually transmitted infections (STIs). 🧪 Always screen for additional infections.
🦟 Aetiology
- Caused by Phthirus pubis, transmitted mainly via intimate skin-to-skin contact (sexual contact most common).
- Partner tracing should include a look-back period of 3 months 🔍.
👀 Clinical Features
- Maculae ceruleae: Blue-grey spots at bite sites — characteristic sign. 🔵
- Persistent itching and irritation in pubic, perianal, or axillary regions.
- Nits (lice eggs) stuck to hair shafts; live lice may be visible with close inspection.
🧪 Investigations
- Clinical diagnosis is usually sufficient — direct visualization of lice or nits. 🔬
💊 Management
- Topical therapy: Apply to all potentially affected sites (genitals, thighs, trunk, axillae, beard/moustache). Reapply after 7–10 days.
- Nit removal: Fine-toothed comb or tweezers to clear visible eggs. ✂️
- Decontamination: Wash bedding, clothes, towels at ≥50°C or dry-clean. Alternatively, seal items in a plastic bag for 3 days. 🧺
- Follow-up: Review at 1 week. If no live lice → considered eradicated ✅.
⭐ First Line Therapy
- Permethrin 1% cream: Apply for 10 min, rinse. Repeat after 7–10 days.
- Pyrethrins + Piperonyl Butoxide: Apply 10 min, rinse. Repeat in 7–10 days.
💡 Second Line Therapy
- Phenothrin 0.2% lotion: Apply for 2 hours, rinse.
- Malathion 0.5% lotion: Apply for 12 hours, rinse.
- Ivermectin (oral): 200 mcg/kg PO, repeat after 7 days (400 mcg/kg in severe cases).
📚 References
