Seborrheic Dermatitis and Hair Casts

Hair Casts in Inflammatory Scalp Disease: A Closer Look at Seborrheic Dermatitis

“Hair Casts” are thin elongated tubular like structures that wrap around the hair shaft. They are generally 2-7 mm in size.

Appearance of hair casts by trichoscopy in a patient with seborrheic dermatitis

Hair casts are said to be “primary” when not associated with any underlying scalp condition and “secondary” when associated with an underlying scalp issue. A variety of inflammatory and non inflammatory conditions lead to hair casts including seborrheic dermatitis(shown here), psoriasis, traction alopecia, scarring alopecia, pemphigus, hair sprays and more. Treatment is centred around treating the acual underlying disorder. For this patient treatment of the seborrheic dermatitis with a combination of zinc pyrithione and ciclopirox shampoos together with a topical steroid containing salicylic acid helped lead to resolution.