Causes
Pubic lice is an infestation by the pubic louse Phthirus pubis.
Clinical presentation
People usually seek medical attention for pubic lice because of pruritus or because they notice lice or nits on their pubic hair.
Pubic lice are typically found attached to hairs in the pubic area. Pubic lice are sometimes are found on coarse hair elsewhere on the body. For example:
- Facial hair - eyebrows, eyelashes, beard, moustache
- Chest
- Armpits
There may be either no symptoms or there may be itch due to hypersensitivity to feeding lice.
Visible eggs (nits) are laid and adhere to the hairs in affected areas.
Blue macules (Maculae caeruleae) may be visible at feeding sites.
Diagnosis
The identification of adult lice or nits is diagnostic.
Nits are often easier to find than lice and resemble poppy-seeds attached to the base of the hair.
A helpful technique is to fasten a piece of transparent adhesive tape to the infested areas. Lice stick to the tape, which then becomes a convenient coverslip for a microscopic slide.
The presence of bruise-like bites or blue macules (Maculae caeruleae). Maculae caeruleae are asymptomatic, macular, blue discolourations on the trunk and thighs.
The presence of dark specks of louse faeces suggest the diagnosis of louse infestation.
Management
Index patient
| Condition | Recommended | Comments |
|---|---|---|
| Pubic lice |
Pyrenel Foam™ (pyrethrins 0.35% + piperonyl butoxide 1.75%) |
Antihistamines can assist with itch, which can last for a few days after treatment. Clothing and bed linen need to be washed (that is, machine-washed, machine-dried using the heat cycle, or dry cleaned) or removed from body contact for at least 72 hours, as lice can only survive for a short time outside the human host. Fumigation of bedding and living areas is not necessary. |
| Pubic lice with eyelash involvement | Petroleum jelly application to eyelashes, twice daily for 10 days | Other facial hair can be treated as per pubic hair |
| Pubic lice resistant to above treatments | Malathion 0.5% lotion (Maldison), applied for 8-12 hours then washed off |
Avoid in pregnancy (B2). Oral ivermectin has been successfully used to treat pubic lice but has only been evaluated in small studies. Currently it isn't licensed for use in pubic lice in Australia. Gamma benzene hexachloride (Lindane®) is not recommended as first-line therapy because of toxicity. |
Contact tracing & partner management
Where sexual contact has occurred within the past month, the sexual partners of patients with pubic lice should be treated.
Sexual contact should be avoided until patients and partners have been treated.
Disclaimer
We recognise that gender identity is fluid. In our treatment guidelines, the words and language we use to describe genitals and gender are based on the sex assigned at birth.
The content of these treatment guidelines is for information purposes only. The treatment guidelines are generic in character and should be applied to individuals only as deemed appropriate by the treating practitioner on a case by case basis. Alfred Health, through MSHC, does not accept liability to any person for the information or advice (or the use of such information or advice) which is provided through these treatment guidelines.
The information contained within these treatment guidelines is provided on the basis that all persons accessing the treatment guidelines undertake responsibility for assessing the relevance and accuracy of the content and its suitability for a particular patient. Responsible use of these guidelines requires that the prescriber is familiar with contraindications and precautions relevant to the various pharmaceutical agents recommended herein.