Also known as DPN (Dermatosis Papulosa Nigra).
Dermatosispapulosanigra describes the presence of multiple, small, 1-5 mm diameter, smooth, firm, black or dark brown papules on face and neck of black-skinned people.
Dermatosispapulosanigra affects about 35% of blacks. There is a lower frequency in those with a fairer complexion. Dermatosispapulosanigra also occurs among dark-skinned Asians and Polynesians, but the exact frequency is unknown. Females are more frequently affected than males.
Dermatosispapulosanigra usually begins in adolescence. The incidence, number and size of lesions increases with age. Lesions occur mainly on the cheeks and forehead but may also be found on the neck, upper back and chest. Scaling, crusting and ulceration do not occur.
The papules are symptomless but may be regarded as unsightly.
Cause of Dermatosispapulosanigra?
The papules of dermatosispapulosanigra are small seborrhoeickeratoses.
Dermatosispapulosanigra is likely to be genetically determined with 40-50% of patients having a family history. It is believed to be due to a naevoid developmental defect of the hair follicle.