Hair casts

Hair casts
Synonyms	Pseudonits, peripilar keratin casts
Pronounce	N/A
Specialty	N/A
Symptoms	White, cylindrical structures encircling the hair shaft
Complications	None
Onset	Any age
Duration	Variable
Types	N/A
Causes	Unknown, possibly related to seborrheic dermatitis or psoriasis
Risks	None
Diagnosis	Clinical examination, differentiation from lice
Differential diagnosis	Pediculosis capitis, dandruff, trichorrhexis nodosa
Prevention	N/A
Treatment	Gentle hair washing, keratolytic agents
Medication	N/A
Prognosis	Excellent
Frequency	Rare
Deaths	N/A

Hair casts or pseudonits are thin, elongated, cylindrical concretions that encircle the hair shaft and can be easily dislodged. They are usually white or yellowish in color and can be seen in normal individuals and in those with various scalp disorders.

Causes

Hair casts can be caused by a variety of factors, including:

• Keratin build-up: This is the most common cause of hair casts. Keratin is a protein that makes up the hair shaft. When it builds up on the scalp, it can form a cast around the hair shaft.
• Scalp conditions: Certain scalp conditions, such as seborrheic dermatitis, psoriasis, and tinea capitis, can cause hair casts.
• Hair care practices: Certain hair care practices, such as excessive use of hair products or infrequent shampooing, can lead to the formation of hair casts.

Diagnosis

Hair casts are usually diagnosed by a dermatologist through a physical examination of the scalp and hair. The dermatologist may also use a dermatoscope to examine the hair shafts more closely. In some cases, a biopsy of the scalp may be needed to confirm the diagnosis.

Treatment

The treatment for hair casts depends on the underlying cause. If the casts are caused by a scalp condition, the dermatologist may prescribe a medicated shampoo or topical treatment. If the casts are caused by hair care practices, the dermatologist may recommend changes in these practices.

See also

• Hair shaft disorders
• Scalp conditions
• Dermatology