Is a condition of many small, benign skin lesions on the face, a condition generally presenting on dark-skinned individuals. DPN is extremely common. From a histological perspective, DPN resembles seborrheic keratoses. The condition may be cosmetically undesirable to some patients.
It 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 of dermatosis papulosa nigra are small seborrheic keratoses.
Dermatosis papulosa nigra 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.
Investigations in dermatosis papulosa nigra
No tests are needed as dermatosis papulosa nigra is diagnosed clinically. If there is any doubt a skin biopsy can be taken. Histology shows the appearance of a seborrhoeic keratosis with markedly increased pigmentation of the basal layer of the epidermis.
Management of dermatosis papulosa nigra
Lesions are generally best left untreated. Complications of locally destructive treatment can include increased and decreased pigmentation, scarring and keloid formation. Treatment choices include curettage, freezing with liquid nitrogen (cryotherapy) and electrodessication followed by curettage. YAG laser has also recently been reported to achieve excellent cosmetic results. Treatment is kept superficial to minimise the risk of complications.