Loose Anagen Syndrome (LAS)

Loose Anagen Syndrome (LAS), also known as loose anagen hair, short anagen syndrome, easily pluckable hair.

Loose anagen syndrome is rather a recently described hair loss disorder affecting predominantly (not exclusively) blond female children. It was first described in 1984. This disorder is characterized by easily and painlessly pluckable anagen hair, which have abnormal morphology. The mechanism of this disorder is not known, but abnormal keratinization of the inner root sheath is suggested. Its incidence is not completely known due to the under-reported cases, but it seems to affect Caucasian people more.

The disorder usually present as general thinning that haircut is never or infrequently needed. Clumps of hair could be removed painlessly during kid playing. This condition is not associated with any nutritional deficiencies and the growth of the affected patients (usually children) is otherwise normal.

In physical examination, sparse growth of thin fine hair may present as diffuse or patchy hair loss. Although hair is not fragile it could be easily and painlessly removed. Hair is usually unkempt and difficult to style. Hair in the other parts of the body is not affected. In microscopic examination the extracted hair are generally in anagen phase. Hair bulb is usually twisted with an acute angle from the shaft. The cuticle has a characteristic of rippled or baggy appearance.

Currently there is no treatment and regrowth is usually spontaneous although hair may never reach its normal length before it is shed.

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References:

1. eMedicine
2. Tricological Society