Telogen Effluvium

Telogen Effluvium (also Discussed in Chapter 19: Hair and Scalp Disorders Resulting in Hair Loss)

Telogen effluvium (TE) is the most common type of alopecia in children and is characterized by diffuse hair thinning.
TE occurs when a triggering event results in the simultaneous shifting of a large number of hairs into the telogen (shedding) phase.
In children, TE is seen in certain clinical scenarios: during the newborn period, after a severe acute illness, a major trauma, surgery, malnutrition or restricted diets, or rarely, in association with medications such as oral contraceptives and isotretinoin.

Clinical Manifestations ⬆ ⬇

Hair shedding and generalized thinning throughout the scalp occurs 3 to 4 months after the triggering event.
Young children rarely notice a change in hair density.
Affected adolescents and parents of young children may report an increased shedding as noted by an increased number of hairs on a brush or comb, on pillows or clothing, or a smaller ponytail size.
Clinical spectrum is variable and may go unnoticed; in general medical attention is sought when >25% of hair is lost.

Clinical Variant ⬆ ⬇

Occipital alopecia of the newborn (Telogen effluvium of the newborn)

Occipital alopecia of the newborn occurring at 3 to 4 months of age is an asymptomatic, ill-defined patch of alopecia localized to the posterior occipital scalp (Fig. 9.6).
After the first few days of life, anagen hairs convert into telogen hairs and as a result a higher proportion of occipital scalp hairs are shed during the first 4 months of life, creating a noticeable patch of alopecia on the posterior scalp.
Friction created by rubbing the posterior scalp on the pillow or mattress is also a factor.
Clinically, the presentation varies from a small patch of relative alopecia to a larger area of complete alopecia.
Spontaneous complete recovery occurs within months, no treatment is required.

Diagnosis ⬆

Clinical examination of the hair and scalp should include a gentle hair pull of 30 to 60 hairs, if telogen effluvium is present >6 hairs will come out easily.
A trichogram showing >20% to 25% of hairs in telogen phase can help establish the diagnosis.

Management

If the trigger has been removed, complete regrowth is expected within months.
If the underlying trigger is sustained, telogen effluvium can become chronic.
Careful discussion with parents about the cause of the condition and its favorable natural history is usually all that is needed.
Shedding typically stops in 3 to 6 months and complete regrowth may take another 6 months.
No treatment is necessary and no treatment is uniformly effective.
However, topical minoxidil 2%, 1 mL applied to the scalp twice daily can promote transition back to anagen.

Helpful Hints

Occasionally TE can unmask androgenetic alopecia in predisposed individuals and a new baseline hair density is set when the TE episode resolves.
Blood tests for a possible underlying cause should be guided by history and physical examination if there are no obvious triggers.
Rate of scalp hair growth is 0.3 mm/day or 1 cm/month.