Pediculosis capitis; the importance of accurate differentiation of nits and hair casts

• Published in: International journal of tropical insect science 2022-02, Vol.42 (1), p.647-650
• Main Authors: Boukan, Afrooz, Mohebi, Leila, Rashti, Roya, Boukan, Akram, Oshaghi, Mohammad Ali
• Format: Article
• Language: English
• Subjects: Adults; Biomedical and Life Sciences; Diagnosis; Differentiation; Eggs; Entomology; Hair; Itching; Life Sciences; Original Research Article; Parasitic diseases; Pediculus humanus; Pruritus; Scalp
• ISSN: 1742-7592; 1742-7584; 1742-7592
• DOI: 10.1007/s42690-021-00586-5

Pediculosis capitis is an ectoparasitosis in which Pediculus humanus capitis (Phthiraptera: Anoplura) infest the human scalp. Infestation is confirmed by the presence of adults, nymphs, or viable eggs (nits). The unhatched eggs of head louse is occupied with an embryo, brownish, and has ovoid construction with a curved end. Nit can be misdiagnosed with hair cast, which are thin, amorphous, extended, whitish cylindrical structure, and freely moveable along the hair shaft. It is very important to correctly differentiate pediculosis from hair cast to avoid anxiety and unnecessary treatment. The purpose of this study is to describe three hair cast and seven pediculosis cases in Dezful health center, southwest Iran. This is a study of ten cases reported in our laboratory in 2017. For each case, microscopic and entomological examination of the hairs were performed. The patients were ten women including eight children and two adults. Clinical signs included itching and skin color changes in all the cases. Microscopic examination showed nits anchored to the hair in seven cases. In the other three cases, the initial diagnosis was confirmed to be hair cast. In all pediculosis cases, the diagnosis of cases was confirmed by entomological examination of hairs, which revealed the presence of nit forms of P. humanus capitis . Differentiation of pediculosis from hair cast can avoid apprehension and pointless treatment.