Hair Shaft Abnormalities – Clues to Diagnosis and Treatment

Abstract

Hair dysplasias are congenital or acquired alterations which often involve the hair shaft. Hair shaft abnormalities are characterized by changes in color, density, length and structure. Hair shaft alterations often result from structural changes within the hair fibers and cuticles which may lead to brittle and uncombable hair. The hair of patients with hair shaft diseases feels dry and looks lusterless. Hair shaft diseases may occur as localized or generalized disorders. Genetic predisposition or exogenous factors produce and maintain hair shaft abnormalities. Hair shaft diseases are separated into those with and those without increased hair fragility. In general, optic microscopy and polarized light microscopy of hair shafts provide important clues to the diagnosis of isolated hair shaft abnormalities or complex syndromes. To establish an exact diagnosis of dysplastic hair shafts, a structured history and physical examination of the whole patient are needed which emphasizes other skin appendages such as the nails, sweat and sebaceous glands. Profound knowledge on hair biology and embryology is necessary to understand the different symptom complexes. Therapy of hair shaft disorders should focus on the cause. In addition, minimizing traumatic influences to hair shafts, such as drying hair with an electric dryer or permanent waves and dyes, is important. A short hairstyle is more suitable for patients with hair shaft disorders.

Trichodaganomania: The compulsive habit of biting one's own hair

“…8 In addition, no hair cuticle or hair shaft abnormalities could be found, ruling out intrinsic shaft disorders that lead to increased fragility, such as monilethrix, trichorrhexis nodosa, pili torti, pili bifurcate, or trichorrhexis invaginata. 9 Another variant of self-inflicted hair loss is trichotemnomania, which is characterized by a compulsive cutting or shaving of the hair. This condition was excluded on the basis of obvious clinical history and examination.…”

Patogênese das lesões associadas à intoxicação por Ramaria flavo-brunnescens em bovinos

“…Na cutícula de cabelos tricotiodistróficos, as camadas A e a exocutícula podem estar ausentes ou descontínuas e glóbulos de material eletrodenso (inclusões cistina-positivas anormais) podem ser identificados na camada A e no interior da endocutícula (Gummer et al 1984, Khumalo et al 2005, como vistas na endocutícula do Bovino 16. A tricotiodistrofia (TTD) é uma doença genética rara que acomete humanos e leva a formação de cabelos frágeis, com diâmetro e contornos irregulares, sendo associada à síntese anormal de proteínas ricas em enxofre, especialmente de cistina (Price et al 1980, Itin & Fistarol 2005. Apesar de não terem sido observadas alterações na camada A da exocutícula no Bovino 16, as demais alterações são muito semelhantes às vistas na TTD, permitindo mais uma vez inferir que as alterações pilosas vistas na intoxicação pelo cogumelo estão relacionadas a um baixo conteúdo de cistina.…”

Hair Loss in Children, Etiologies, and Treatment

“…Hair shaft abnormalities are characterized by changes in color, density, length, and structure [10]. Hair shaft alterations often result from structural changes within the hair fibers and cuticles, which may lead to brittle and uncombable hair.…”