Pediculus capitis (head louse)
Jump to navigation
Jump to search
Epidemiology
- transmitted directly from person to person & by shared hats & combs or brushes
- prevalence is greatest in school-aged girls with long hair
- black children are less frequently affected than other children
- females firmly cement their eggs to hair
- nits or eggs generally hatch in 8-9 days
- see ref[2] for pictures
Clinical manifestations
- excoriations of pruritic lesions on the scalp, neck & shoulders leading to:
- oozing
- crusting
- matting of hair
- bacterial infections
- regional lymphadenopathy
- examination:
- combing through wet, conditioned hair with a fine-toothed comb (scalp inspection is insufficient)[3]
Management
- do not treat a child unless live lice or eggs (not just empty nit cases) are present
- topical permethrin 1% or malathion 0.5%
- kills lice & most eggs, but will not kill newly laid eggs that have not yet developed a nervous system[7]
- apply & leave on overnight, rinse in morning
- combine with nit combing[12]
- up to 2 additional treatments spaced 9 days apart may be needed[7]
- at least 1 additional treatment 9 days later recommended[11]
- piperonyl butoxide/pyrethrin (4%/0.3%) shampoo[12]
- 1% lindane or 5% benzyl alcohol lotion
- spinosad (Natroba) FDA-approved Jan 2011
- ivermectin
- diethylcarbamazine, albendazole probably ineffective[4]
- comb hair after treatment with fine-toothed nit comb to remove nits
- combs & brushes should be disinfected in hot water at 65 degrees C for 5 minutes or soaked in insecticide for 1 hour
- in areas with proven resistance, parents may consider manual methods such as wet-combing or using petroleum jelly to suffocate the lice[11]
- children should miss school because of head lice; odds of transmission are low[11]
More general terms
Additional terms
- lindane (Kwell, Scabene)
- pediculosis; phthiriasis (lice infestation, vagabond disease)
- permethrin (Elimite, Nix)
References
- ↑ Harrison's Principles of Internal Medicine, 13th ed. Isselbacher et al (eds), McGraw-Hill Inc. NY, 1994, pg 935-36
- ↑ 2.0 2.1 Roberts RJ. Clinical practice. Head lice. N Engl J Med. 2002 May 23;346(21):1645-50. Review. Picture of louse & of unhatched nit. No abstract available. PMID: https://www.ncbi.nlm.nih.gov/pubmed/12023998
- ↑ 3.0 3.1 Jahnke C et al Accuracy of Diagnosis of Pediculosis Capitis: Visual Inspection vs Wet Combing Arch Dermatol 2009 145(3) March 2009 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/19289764 <Internet> http://archderm.ama-assn.org/cgi/content/short/145/3/309
- ↑ 4.0 4.1 4.2 Munirathinam A et al. Impact of ivermectin drug combinations on Pediculus humanus capitis infestation in primary schoolchildren of south Indian rural villages. Int J Dermatol 2009 Nov; 48:1201. PMID: https://www.ncbi.nlm.nih.gov/pubmed/20064176
- ↑ 5.0 5.1 Chosidow O et al. Oral ivermectin versus malathion lotion for difficult-to- treat head lice. N Engl J Med 2010 Mar 11; 362:896 PMID: https://www.ncbi.nlm.nih.gov/pubmed/20220184
- ↑ Prescriber's Letter 17(5): 2010 COMMENTARY: Ivermectin (Stromectol) for Head Lice GUIDELINES: Diagnosis and Treatment of Head Lice (NGC Summary, 2008) PATIENT HANDOUT: Treating Head Lice PATIENT HANDOUT SPANISH VERSION: El Tratamiento de Piojos de la Cabeza Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=260523&pb=PRL (subscription needed) http://www.prescribersletter.com
- ↑ 7.0 7.1 7.2 7.3 Prescriber's Letter 17(9): 2010 COMMENTARY: Treatment of Head Lice - An Update PATIENT HANDOUT: Treating Head Lice PATIENT HANDOUT SPANISH VERSION: El Tratamiento de Piojos de la Cabeza GUIDELINES: Head Lice Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=260911&pb=PRL (subscription needed) http://www.prescribersletter.com
- ↑ Prescriber's Letter 18(9): 2011 Commentary: Natroba (Spinosad) for the Treatment of Head Lice Patient Handout: Treating Head Lice Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=270904&pb=PRL (subscription needed) http://www.prescribersletter.com
- ↑ Frankowski BL et al, Council on School Health and Committee on Infectious Diseases American Academy of Pediatrics Head Lice Pediatrics 2010 126:392-403 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/20660553 <Internet> http://pediatrics.aappublications.org/content/126/2/392.full.html
- ↑ 10.0 10.1 Pariser DM et al Topical 0.5% Ivermectin Lotion for Treatment of Head Lice N Engl J Med 2012; 367:1687-1693 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/23113480 <Internet> http://www.nejm.org/doi/full/10.1056/NEJMoa1200107
Chosidow O and Giraudeau B Topical Ivermectin - A Step toward Making Head Lice Dead Lice? N Engl J Med 2012; 367:1750-1752 PMID: https://www.ncbi.nlm.nih.gov/pubmed/23113487 - ↑ 11.0 11.1 11.2 11.3 Devore CD, Schutze GE. COUNCIL ON SCHOOL HEALTH AND COMMITTEE ON INFECTIOUS DISEASES. Head Lice Pediatrics. April 27, 2015 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25917986 <Internet> http://pediatrics.aappublications.org/content/early/2015/04/21/peds.2015-0746
- ↑ 12.0 12.1 12.2 12.3 12.4 12.5 Medical Knowledge Self Assessment Program (MKSAP) 17, American College of Physicians, Philadelphia 2015