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Bamboo
hair
Bamboo hair, also known as trichorrhexis invaginata, is very distinctive.
The hair fibers have the shape of bamboo. Instead of being smooth
along their length, the fibers have focal nodules that make the
fiber look like bamboo. The nodules are focal defects in the fiber
where a cup and ball shape has developed. The hair closest to the
scalp forms a bulge with a cup shape form in which the hair fiber
further away from the scalp sits. These defects are weak spots in
the hair that are easily broken. The piece of hair that sits in
the cup shape gets pulled out leaving the exposed socket. This is
now called a golf tee hair because of its shape.
 Bamboo
hair is often seen along side other hair fibers the have focal twists
in them. These twists, called torsion nodes, create stress on the
chemical bonds in the hair and are also weak points where hair fiber
is liable to break if pulled.
These bamboo hairs and golf tee hairs can occasionally develop
in normal hair from over processing but more likely trichorrhexis
invaginata is a congenital defect often a symptom of another disease.
Netherton's syndrome is a disease that can involve bamboo hair as
well as ichthyosis and atopy. Netherton's syndrome is usually evident
from birth with flaking skin, red rashes and sparse hair growth
involving fragile bamboo hair.
Netherton's syndrome is probably the result of an autosomal recessive
gene expression. The gene seems to be involved in keratinization
of the hair cortex. Examination of hair fibers has shown that the
cuticle is normal but the internal cortex is not completely keratinized
at sporadic points along its length. These incompletely keratinized
areas are soft and weak and the hard, fully keratinized portions
of the fiber become impacted into the soft portion creating the
cup and socket structure. The improperly keratinized areas of the
hair fiber can also become twisted making torsion nodes.
Bamboo hair often improves spontaneously as the individual grows.
Most treatments involve preventative measures to avoid over processing
and physical manipulation. Several treatments are available to remedy
skin problems that develop in ichthyosis and Netherton's syndrome
and these may also help improve hair quality.
Bamboo
hair references
- Ito M,
Ito K, Hashimoto K. Pathogenesis in trichorrhexis invaginata (bamboo
hair). J Invest Dermatol. 1984 Jul;83(1):1-6.
- Haas OA,
Martins da Cunha A, Gadner H, Stingl G, Kornmuller R. [The Netherton
syndrome: clinical characteristics, differential diagnosis and
new ways of therapy]. Padiatr Padol. 1984;19(2):153-9.
- Smith DL,
Smith JG, Wong SW, deShazo RD. Netherton's syndrome: a syndrome
of elevated IgE and characteristic skin and hair findings. J Allergy
Clin Immunol. 1995 Jan;95(1 Pt 1):116-23.
- de Berker
DA, Paige DG, Ferguson DJ, Dawber RP. Golf tee hairs in Netherton
disease. Pediatr Dermatol. 1995 Mar;12(1):7-11.
- Powell
J, Dawber RP, Ferguson DJ, Griffiths WA. Netherton's syndrome:
increased likelihood of diagnosis by examining eyebrow hairs.
Br J Dermatol. 1999 Sep;141(3):544-6.
- Chavanas
S, Garner C, Bodemer C, Ali M, Teillac DH, Wilkinson J, Bonafe
JL, Paradisi M, Kelsell DP, Ansai Si, Mitsuhashi Y, Larregue M,
Leigh IM, Harper JI, Taieb A, Prost Yd, Cardon LR, Hovnanian A.
Localization of the Netherton syndrome gene to chromosome 5q32,
by linkage analysis and homozygosity mapping. Am J Hum Genet.
2000 Mar;66(3):914-21.
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