Int J Trichology. 2011 Jul-Dec; 3(2): 121–122. doi: 10.4103/0974-7753.90834 PMCID: PMC3250010 Hair Casts or Pseudonits Katlein França, Ricardo Tadeu Villa, Isabella Rezende Silva, Cristine Almeida de Carvalho, and Valcinir Bedin Department of Dermatology, Fundação Educacional Souza Marques, São Paulo, Brazil Address for correspondence: Dr. Katlein França, Rua São Domingos, No. 69- Bela Vista, São Paulo-SP, CEP: 01326-000, Brazil. E-mail: kf.dermatologia@gmail.com Copyright : © International Journal of Trichology This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Hair casts or pseudonits are thin, elongated, cylindrical concretions that encircle the hair shaft and can be easily dislodged. A case of pseudonits in a 9-year-old girl is reported. Though not unusual, false diagnoses are common. Keywords: Hair casts, hair diseases, pseudonits, scalp dermatitis INTRODUCTION Hair casts or pseudonits are 2-7 mm long, discrete, firm, shiny, white, freely movable tubular accretions that encircle the hair shafts of the scalp.[ 1 ] Even though they are not unusual, there is scarce literature on them and underdiagnosis is common. They often occur in great numbers and must be correctly differentiated from pediculosis capitis. Hair casts are indeed common in psoriasis, pityriasis amiantacea, pityriasis capitis and seborrheic dermatitis.[ 2] False diagnoses are common, which implies inadequate treatment and becomes a reason for both patient and physician anxiety.[ 3] The objective of this article is to present a case of hair casts in a child mistreated previously and to discuss this relatively rare condition of the scalp. CASE REPORT A 9-year-old girl presented to consultation with asymptomatic small whitish lesions resembling nits, attached to the hair shaft. Nit like formations on the scalp had been noticed since the girl was 2 years old. Other family members were not affected by similar disorder. She was referred from a pediatric clinic with a diagnosis of pediculus capitis and had been treated with ketoconazole and scabicide shampoo, without any improvement. The dermatological examination showed white cylinders, easily deployable, located distal, medial and proximal to the hairs, especially on the occipital and parietal regions, bilaterally [ Figure 1 ]. Mycological culture of hair casts and scalp were performed and both were negative. Capillaroscopy revealed a cylindrical and hyaline mass involving the hair shaft [ Figure 2]. DISCUSSION Despite the small number of cases reported in literature, hair casts do not seem to be rare. Apparently, they are more common in females, particularly in patients who subject their hair to excessive traction for a long period.[ 4] Hair Casts or Pseudonits http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3250010/?report=printable 1 of 6 2012-11-05 9:59 AM