Woolly hair: a rare disorder

Woolly hair: a rare disorder: Jyoti Budhwar, Chetna Singla



Egyptian Journal of Dermatology and Venerology 2020 40(1):66-67



Sir,

Woolly hair is a rare congenital structural anomaly of scalp hair. It is either sporadic or genetic. Hair is extremely curly, and the texture resembles sheep’s wool, whereas the hair color often shows no unusual characteristics [1]. The rate of hair growth is usually normal, but the anagen phase is truncated, resulting in shorter hair. The hair shaft exhibits elliptical cross-section, axial rotation, and kink formation. The condition was first observed and described in a European family by Gossage [2]. It is different from the curly hair of black people, in that the curled hair of black people lies separately, whereas the curls of woolly hair usually merge.

A 10-year-old female child born of a nonconsanguineous marriage presented with complaints of short, curly brittle hair since birth ([Figure 1] and [Figure 2]). Similar complaints were also present in an 8-year-old female sibling ([Figure 3] and [Figure 4]). There were no similar complaints in parents and relatives. There was no history suggestive of physical and mental retardation. Examination of scalp revealed the presence of fine, short, coiled, and poorly pigmented hair. There were sparse body hair and partial loss of lateral third of eyebrows. Nails and teeth were normal. Systemic examination and routine hematological investigations were within the normal limits. Light microscopy of hair showed a slight variation in the thickness of the shaft, and potassium hydroxide examination result of hair was normal. Based on clinical findings and no systemic involvement, diagnosis of autosomal-recessive variant of woolly hair was made.

Figure 1 Woolly hair on the scalp and partial loss of lateral third of eyebrows. Click here to view

Figure 2 Close-up. Click here to view

Figure 3 Sibling having woolly hair and partial loss of lateral third of eyebrows. Click here to view

Figure 4 Close-up. Click here to view

Woolly hair can appear as a part of systemic disease (woolly hair syndrome) or without systemic findings (nonsyndromic woolly hair). Nonsyndromic woolly hair can be inherited as either an autosomal dominant or recessive disorder. An earlier classification has described four types of woolly hair: hereditary woolly hair, familial woolly hair, symmetrical circumscribed allotrichia, and woolly hair nevus [3]. In the literature, woolly hair has been associated with ichthyosis, keratosis pilaris, deafness, acral keratoderma, nail changes, and dental and facial abnormalities [4],[5].

Two characteristic associations of woolly hair are Naxos disease and Carvajal disease. Naxos disease is characterized by woolly hair, palmoplantar keratoderma, and dilated cardiomyopathy with right ventricular dysplasia. It is an autosomal-recessive disorder occurring owing to mutation in the plakoglobin gene. Carvajal disease is similar clinically to Naxos disease, except for left ventricular involvement and presentation at a younger age, and it is due to mutation in the desmoplakin gene [6].

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Conflicts of interest

There are no conflicts of interest.



 

References

1.	Ramot Y, Zlotogorski A. The twisting tale of woolly hair: a trait with many causes. J Med Genet 2015; 52:217–223.
2.	Gossage AM. The inheritance of certain human abnormalities. Quart J Med 1907; 1:331–347.
3.	Hutchison PE, Cairns RJ, Wells RS. Woolly hair. Trans St Johns Hosp Dermatol Soc 1974; 60:160–176.
4.	Vasudevan B, Verma R, Pragasam V, Badad A. A rare case of woolly hair with unusual associations. Indian Dermatol Online J 2013; 4:222–224.   [PUBMED]  [Full text]
5.	Lacarrubba F, Dall’Oglio F, Rossi A, Schwartz RA, Micali G. Familial keratosis follicularis spinulosa decalvans associated with woolly hair. Int J Dermatol 2007; 46:840–843.
6.	Norgett EE, Hatsell SJ, Carvajal-Huerta L, Cabezas JC, Common J, Purkis PE et al. Recessive mutation in desmoplakin disrupts desmoplakin-intermediate filament interactions and causes dilated cardiomyopathy, woolly hair and keratoderma. Hum Molec Genet 2000; 9:2761–2766.

Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]