Woolly Hair Syndrome

Woolly hair syndrome is a group of conditions in which the scalp hair is tightly curled, fine and short, in people who are not of African descent. It is either localised (woolly hair naevus) or generalised, and either isolated or part of a syndrome.

Isolated woolly hair is inherited as autosomal dominant (KRT74, KRT71) or autosomal recessive (LIPH, LPAR6, P2RY5) traits. Woolly hair naevus affects a patch of hair, is non-hereditary and can be associated with an epidermal naevus.

Woolly hair with palmoplantar keratoderma and arrhythmogenic cardiomyopathy occurs in Naxos disease (JUP, autosomal recessive) and Carvajal syndrome (DSP).

Pathophysiology.

Variants affect hair keratins or hair follicle structure (lipase H and its lysophosphatidic acid receptor), and cause abnormal shaft curvature. In Naxos disease and Carvajal syndrome, defective desmosome proteins (plakoglobin, desmoplakin) disrupt cell adhesion in hair, skin and heart.

• Tightly curled, fine, lighter hair that is slow to grow, from birth or early childhood. Eyebrows and lashes may be affected.
• Hypotrichosis (LIPH, LPAR6), and a lack of pigment in some.
• Syndromic forms: thickened palms and soles from infancy, and cardiomyopathy appearing in adolescence or adulthood, with palpitations, syncope or sudden death.

Red flags.

• Woolly hair with palmoplantar keratoderma, syncope, palpitations or a family history of sudden death or heart failure.

• Clinical diagnosis from the hair and family history. Examination of palms and soles.
• Light microscopy of hair shows twisting and sometimes trichorrhexis nodosa or pili torti.
• Gene testing (KRT74, LIPH, LPAR6, JUP, DSP). In patients with keratoderma: ECG, 24-hour Holter monitoring, echocardiography and cardiac MRI at diagnosis.

Differential diagnosis.

• Uncombable hair syndrome and other hair shaft disorders.
• Hair texture of tightly curled hair in people of African descent (normal).
• Other syndromes with keratoderma and cardiomyopathy.

• Isolated forms: reassure the family and use gentle hair care, with no specific treatment. Hair may become less curly with age.
• Syndromic forms: cardiology care with beta blockers, antiarrhythmic drugs and an implantable defibrillator for patients at high risk of sudden death. Restrict competitive exercise.
• Keratoderma: emollients with urea 10 to 20% or salicylic acid 5 to 10%.
• Genetic counselling and family testing.

Special groups. Children in families with Naxos disease or Carvajal syndrome: cardiac screening yearly from adolescence.

Monitoring. Cardiac review every 6 to 12 months in syndromic forms.

Referral and escalation. Cardiology and genetics for any patient with woolly hair and keratoderma; urgent review for syncope or palpitations.