Hair disorders

Question 1

Loose anagen (growing hair) syndrome

Answer 1

This presents as very thin wispy new growth hair

• usually in children <5 yrs.

Usually improves with age.

Question 2

Traction alopecia

Answer 2

Traction alopecia is thinning of the hair seen in the forehead area

• due to very tight hair styles (e.g. hair braiding) in female children.

Question 3

Trichotillomania (hair pulling)

Answer 3

This may occur during the night as a habit

• parents may be unaware of the hair pulling.

A characteristic feature is:

• an irregular shaped area of incomplete patchy alopecia
• containing hairs of different length, due to the fact that some hairs will not break with pulling while others will break at varying distances from the scalp surface.
• There may be associated follicular pustules or perifollicular petechiae.

However, scrapings should be taken to exclude a particular type of tinea capitis (black dot ringworm) caused by Trichophyton tonsurans.

The management is similar to thumb sucking or nail biting with a low key approach.

Question 4

Localised alopecia areata

Answer 4

This presents as a circumscribed area with a normal ‘clean’ scalp surface.

A pathognomic feature is the presence of ‘exclamation mark’ hairs at the margins:

• hairs ~5–10 mm long wider at the top than the base

If recent or progressive, treat with a potent topical steroid for 12 wks.

Question 5

Tinea capitis

Answer 5

Dermatophyte infection

• produces an area of incomplete ‘unclean’ alopecia
• with various degrees of scaling and inflammation of the scalp surface.

A boggy swelling (Kerion) can develop in severe cases.

Wood’s light examination will be positive in only 50% of cases.

Confirm diagnosis with scalp scrapings for microscopy and culture.