Atrichia with papular lesions.

Atrichia with papular lesions (APL) is a rare autosomal recessive form of irreversible alopecia with onset at few months of age with papular keratin cysts over the body. It is associated with mutation in the Zinc finger domain of the human hairless gene on chromosome region 8p12. An eleven-year-old male presented with extensive alopecia starting at six months of age refractory to the treatment along with keratotic papules on the face and trunk. Biopsy from a papule showed mid-dermal keratin cysts and from the scalp showed few vellus follicles with no terminal hairs. The diagnosis of APL was made based upon the criteria proposed. Vitamin D-dependent rickets was ruled out as it has similar clinical presentation. Accurate diagnosis of APL is required to avoid unnecessary treatment to the patient as it is commonly misdiagnosed as alopecia universalis and treated with systemic steroids.