AUTHOR AND EDITOR INFORMATION

Section 1 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

INTRODUCTION

Section 2 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

Background

The essential abnormality of trichorrhexis nodosa is the formation of nodes along the hair shaft through which breakage readily occurs. In 1852, Samuel Wilks of Guy's Hospital first described the condition, although the term trichorrhexis nodosa was not proposed until 1876 by M. Kaposi. Trichorrhexis nodosa is ultimately a response to physical or chemical trauma. It may be acquired in patients with normal hair through exposure to a sufficient level of trauma. Trichorrhexis nodosa may also be congenital, occurring in defective, abnormally fragile hair following trivial injury. It is the most common congenital defect of the hair shaft.

Pathophysiology

Macroscopically, hair shafts affected by trichorrhexis nodosa contain small white nodes at irregular intervals throughout the length of the shaft. The number of nodes may vary from one to several, depending on the length of the hair. These nodes represent areas of cuticular cell disruption, which allows the underlying cortical fibers to separate and fray. The cortical fibers splay outwards and fracture, giving the node the microscopic appearance of 2 brooms or paintbrushes thrust together end to end by their bristles. Complete breakage often occurs at these nodes. The fractured hairs are found mainly on the scalp, but they also may involve body or pubic hair.

Physical traumas that may cause sufficient damage to the hair shaft include excessive brushing, back combing, stressed hairstyles, the application of heat, and prolonged exposure to ultraviolet light. Head rolling and banging; habit tics; trichotillomania; and the scratching and pulling associated with pruritic dermatoses, such as seborrheic dermatitis and pediculosis capitis, can also result in sufficient damage. Chemical traumas include excessive exposure to salt water, shampooing, setting, perming, bleaching, and dyeing of hair.

Seasonal recurrence of trichorrhexis nodosa has been reported as the result of the cumulative effect of diverse insults to the hair.¹ The manifestations appear each summer when repeated soaking in salt water and exposure to ultraviolet light were superimposed on the traumas of shampooing and hair brushing. Trichorrhexis nodosa has also resulted from the use of chemical hair straighteners and selenium shampoo and from trauma induced by infestation with trichomycosis axillaris. Numerous studies have reproduced trichorrhexis nodosa in both normal and affected hairs by exposing them to simulated physical and chemical trauma.

Although trichorrhexis nodosa primarily occurs in normal hairs exposed to a sufficient degree of trauma, it has also been observed in patients who have an underlying weakness of the hair shaft due to a structural abnormality. Structural abnormalities associated with increased fragility include trichorrhexis invaginata (bamboo hair), pili torti, monilethrix, and pseudomonilethrix. The hairs formed in these disorders demonstrate distinctive patterns of defects that result in brittle hairs. These disorders are hereditary in nature and follow autosomal dominant or recessive patterns of inheritance. See Trichorrhexis Invaginata (Netherton Syndrome or Bamboo Hair) and Monilethrix.

Trichorrhexis invaginata is an autosomal recessive disorder characterized by nodular ball-and-socket deformities resulting from intussusception of the hair shaft at the zone of keratinization. The hairs in cases of pili torti are flattened and twisted 180° around their long axis at irregular intervals along the shaft. Inheritance is autosomal dominant, although sporadic cases have been reported. Hairs affected by monilethrix show elliptical nodes separated by narrower internodes where the medulla is lacking. Hairs of pseudomonilethrix show irregular nodes, which are the protruding edges of depressions in the shaft. Both disorders are autosomal dominant in inheritance. These structural defects result in brittle hairs that are more susceptible to the effects of trauma; therefore, they are likely to demonstrate the nodes of trichorrhexis nodosa.

The underlying structural weakness of the hair shaft may result from impaired keratin formation. Hairs weakened by impaired keratin formation are seen in argininosuccinic aciduria, trichothiodystrophy, and Menkes disease.

Argininosuccinic aciduria is the autosomal recessive deficiency of argininosuccinase, the enzyme that cleaves argininosuccinic acid into arginine and fumaric acid in the urea cycle. Hair normally contains 10.5% arginine by weight. The deficiency in arginine resulting from this disorder produces weak hair with a tendency to fracture.² The rare inborn deficiency of argininosuccinic acid synthetase results in low arginine levels and brittle hair. Sulfur and the sulfur-containing amino acid cystine are also important components of the hair shaft. They allow for the formation of disulfide bonds, which account in part for the strength of keratin. In cases of trichothiodystrophy, low sulfur and cystine content result in defective keratin formation and weakened hairs. The characteristic hair-shaft defect in trichothiodystrophy is a transverse fracture called trichoschisis, but trichorrhexis nodosa can also be seen.

Menkes disease is a sex-linked recessive disorder characterized by a defect in the metabolism of copper, resulting in low serum copper levels. The enzymes involved in keratin formation are copper dependent. Therefore, patients with this disorder have an inherent defect in keratinization, resulting in a twisting of hairs (pili torti) as well as weakened hairs and trichorrhexis nodosa. The hairs resulting from these metabolic and genetic defects are more susceptible to the effects of trauma; therefore, they are likely to demonstrate the nodes of trichorrhexis nodosa (see Menkes Kinky Hair Disease).

A primary congenital form of trichorrhexis nodosa is inherited as an autosomal dominant trait in some families. This form may occur as an isolated defect or with other minor ectodermal abnormalities.

Trichorrhexis nodosa has also been described in a case of hypothyroidism.³ The accumulation of mucin in the outer root sheath is postulated to press on the inner root sheath, causing the hair-shaft defect. This accumulation may cause a defect in the differentiation and maturation of matrix cells, causing a growth defect in the hair shaft.

Frequency

United States

• Trichorrhexis nodosa is an uncommon disease.

Race

• Acquired proximal trichorrhexis nodosa is common in blacks, and it appears to occur in individuals who are genetically predisposed.
• Acquired distal trichorrhexis nodosa primarily occurs in Asian or white persons.

Sex

• Acquired proximal trichorrhexis nodosa is more common in females than in males.

Age

• Congential trichorrhexis nodosa may be present at birth, or it may appear within the first couple months of life. It can present in patients with the late form of argininosuccinic aciduria at age 2 years or older.
• Acquired trichorrhexis nodosa usually presents in early to middle life.

CLINICAL

Section 3 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

History

Patients with trichorrhexis nodosa present with a history of white flecking and abnormal fragility of the hair and failure to attain normal hair length.

• Congenital trichorrhexis nodosa becomes apparent at a young age. It may occur alone or in conjunction with the characteristic defects of the underlying disorder.
• • Possible congenital underlying disorders include Menkes disease, argininosuccinic aciduria, and trichothiodystrophy.
  • Common concurrent symptoms are mental retardation,⁴ motor defects, growth failure, and seizures.
  • Other associated symptoms may include nail and skin changes (ichthyosis), photosensitivity, ocular dystrophy, and infertility.
  • A family history of similar hair problems or of convulsive disorder, mental deficiency, or other inheritable syndrome may indicate a congenital cause for trichorrhexis nodosa.
• Acquired trichorrhexis nodosa falls into 3 basic categories: proximal, distal, and localized.
• • Proximal trichorrhexis nodosa is common in blacks that use caustic chemicals (relaxers) when styling their hair. The involved hairs develop the characteristic nodes and break a few centimeters from the skin surface in areas subject to friction from combing or sleeping. This breakage results in areas of alopecia. Some people appear to be more susceptible than others, perhaps on a genetic basis.
  • Distal trichorrhexis nodosa primarily occurs in white or Asian individuals. Nodes and breakage occur several inches from the scalp, producing hair that appears dull and uneven. Breakage is usually the result of excessive hair styling and is commonly associated with trichoptilosis, or longitudinal splitting, also referred to as split ends.
  • Localized trichorrhexis nodosa occurs in a patch, usually a few centimeters across. It is usually accompanied by a pruritic dermatosis, such as circumscribed neurodermatitis, contact dermatitis, or atopic dermatitis. Scratching and rubbing are most likely the ultimate cause.
• All patients should be questioned about their routine hair care habits and environmental or chemical exposures to determine the source of physical or chemical trauma.
• Trichorrhexis nodosa is seen with Menkes disease. Epilepsy is one of its main features: early focal status, then infantile spasms, and then myoclonic and multifocal epilepsy after age 2 years.⁵

Physical

• On clinical inspection, 1 or more nodes are found as whitish specks on the affected hair shaft.
• The number of nodes varies, depending on the length of the shaft.
• Affected hairs of the scalp can be patchy or diffuse in distribution.
• Body and pubic hairs may be involved.
• Examination of the underlying skin may reveal lichenification or a pruritic dermatosis, especially in cases of acquired localized trichorrhexis nodosa.

Causes

• Trichorrhexis nodosa is the result of physical or chemical trauma to the hair shaft.
• A primary congenital form of trichorrhexis nodosa is inherited as an autosomal dominant trait in some families.
• See Pathophysiology.

DIFFERENTIALS

Section 4 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

Other Problems to be Considered

Pediculosis
Peripilar casts
Dermatophytosis
Trichothiodystrophy
Argininosuccinic aciduria
Deposits of extraneous material
Hypothyroidism

Patients with syndromic diarrhea, also known as phenotypic diarrhea or tricho-hepato-enteric syndrome, have a congenital enteropathy with a distinct hair abnormality characterized by woolly hair that is easily removed and poorly pigmented. Hair-shaft microscopic analysis may show twisted hair (pili torti), anisotrichosis and poilkilotrichosis, trichorrhexis nodosa and longitudinal breaks, and trichothiodystrophy.⁶

A feature of normal healthy black African hair is an apparent increased fragility, with certain similarities to that reported for trichorrhexis nodosa (weathering secondary to physical damage).⁷ This excessive structural damage is probably due to physical trauma (resulting from grooming) rather than an inherent weakness due to any structural abnormality.

WORKUP

Section 5 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

Lab Studies

• Light and electron microscopy of the affected areas reveal a decreased or absent cuticular cell layer and the characteristic paintbrush bristle appearance of trichorrhexis nodosa. In patients with underlying trichothiodystrophy, polarized light shows the typical appearance of alternating light and dark bands on the shaft, the so-called tiger-tail pattern.⁸ Fungal microscopy and culture may be performed if necessary.
• Patients suspected of having an underlying congenital disorder because of a young age at onset and because of the presence of associated symptoms warrant further investigation.
• • Analysis of the hair shaft may reveal a chemical deficiency caused by a metabolic disorder (eg, low sulfur level in trichothiodystrophy).
  • Serum and urine amino acid levels should be investigated.
  • Other blood tests may include copper level tests, iron studies, blood cell counts, and liver and thyroid function tests.

Imaging Studies

• A CT of the brain and an EEG may aid in diagnosis if mental retardation is present.

TREATMENT

Section 6 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

Medical Care

Regardless of the presence or the absence of an underlying defect of the hair shaft, trichorrhexis nodosa is ultimately the result of trauma. Therefore, treatment is aimed at minimizing physical or chemical trauma.

• Excessive brushing, hot combing, permanent waving, and other harsh hair treatments should be avoided.
• In acquired localized trichorrhexis nodosa, the underlying pruritic dermatosis should be treated to prevent trauma from scratching or rubbing.
• Underlying metabolic disorders are treated accordingly, usually through the implementation of a specifically tailored diet.

FOLLOW-UP

Section 7 of 8  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

Deterrence/Prevention

• Patients should avoid physical and chemical trauma to the hair shaft. See Pathophysiology.

Prognosis

• Acquired trichorrhexis nodosa is reversible with the avoidance of physical and chemical trauma. Complete resolution may take 2-4 years, depending on the growth of new anagen hairs.

REFERENCES

Section 8 of 8

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• References

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2. Fichtel JC, Richards JA, Davis LS. Trichorrhexis nodosa secondary to argininosuccinicaciduria. Pediatr Dermatol. Jan-Feb 2007;24(1):25-7. [Medline].
3. Lurie R, Hodak E, Ginzburg A, David M. Trichorrhexis nodosa: a manifestation of hypothyroidism. Cutis. May 1996;57(5):358-9. [Medline].
4. Pollitt RJ, Jenner FA, Davies M. Sibs with mental and physical retardation and trichorrhexis nodosa with abnormal amino acid composition of the hair. Arch Dis Child. Apr 1968;43(228):211-6. [Medline].
5. Bahi-Buisson N, Kaminska A, Nabbout R, Barnerias C, Desguerre I, De Lonlay P, et al. Epilepsy in menkes disease: analysis of clinical stages. Epilepsia. Feb 2006;47(2):380-6. [Medline].
6. Goulet O, Vinson C, Roquelaure B, Brousse N, Bodemer C, Cézard JP. Syndromic (phenotypic) diarrhea in early infancy. Orphanet J Rare Dis. Feb 28 2008;3:6. [Medline].
7. Khumalo NP, Dawber RP, Ferguson DJ. Apparent fragility of African hair is unrelated to the cystine-rich protein distribution: a cytochemical electron microscopic study. Exp Dermatol. Apr 2005;14(4):311-4. [Medline].
8. Liang C, Kraemer KH, Morris A, Schiffmann R, Price VH, Menefee E, et al. Characterization of tiger-tail banding and hair shaft abnormalities in trichothiodystrophy. J Am Acad Dermatol. Feb 2005;52(2):224-32. [Medline].
9. Burkhart CG, Burkhart CN. Trichorrhexis nodosa revisited. Skinmed. Mar-Apr 2007;6(2):57-8. [Medline].
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11. Chernosky ME, Owens DW. Trichorrhexis nodosa. Clinical and investigative studies. Arch Dermatol. Nov 1966;94(5):577-85. [Medline].
12. Chetty GN, Kamalam A, Thambiah AS. Acquired structural defects of the hair. Int J Dermatol. Mar 1981;20(2):119-21. [Medline].
13. Coulter DL, Beals TF, Allen RJ. Neurotrichosis: hair-shaft abnormalities associated with neurological diseases. Dev Med Child Neurol. Oct 1982;24(5):634-44. [Medline].
14. Freedburg IM, Eisen AZ, Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 5^th ed. New York, NY: McGraw Hill; 1999.
15. Itin PH, Mattarelli G, Bircher AJ, Zuberbuhler E, Guggenheim R. Localized trichorrhexis nodosa. Br J Dermatol. Dec 1992;127(6):656-7. [Medline].
16. Leonard JN, Gummer CL, Dawber RP. Generalized trichorrhexis nodosa. Br J Dermatol. Jul 1980;103(1):85-90. [Medline].
17. Owens DW, Chernosky ME. Trichorrhexis nodosa; in vitro reproduction. Arch Dermatol. Nov 1966;94(5):586-8. [Medline].
18. Peter C, Tomczok J, Hoting E, Behrendt H. Trichothiodystrophy without associated neuroectodermal defects. Br J Dermatol. Jul 1998;139(1):137-40. [Medline].
19. Rogers M. Hair shaft abnormalities: Part I. Australas J Dermatol. Nov 1995;36(4):179-84; quiz 185-6. [Medline].
20. Rushton DH, Norris MJ, James KC. Amino-acid composition in trichorrhexis nodosa. Clin Exp Dermatol. Jan 1990;15(1):24-8. [Medline].
21. Smith RA, Ross JS, Bunker CB. Localized trichorrhexis nodosa. Clin Exp Dermatol. Sep 1994;19(5):441-2. [Medline].
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Article Last Updated: May 1, 2008