You are in: eMedicine Specialties > Dermatology > BENIGN NEOPLASMS Dermatosis Papulosa NigraArticle Last Updated: Dec 4, 2006AUTHOR AND EDITOR INFORMATIONAuthor: Mehran Nowfar-Rad, MD, Assistant Clinical Professor, Division of Dermatology, David Geffen School of Medicine University California at Los Angeles Mehran Nowfar-Rad is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, and American Medical Association Coauthor(s): Frederick Fish, MD, Director, Department of Dermatology and Cutaneous Surgery, St Paul Ramsey Medical Center; Associate Clinical Professor, Department of Dermatology, University of Minnesota Editors: Kathryn Schwarzenberger, MD, Associate Professor of Medicine, Division of Dermatology, University of Vermont College of Medicine; Consulting Staff, Division of Dermatology, Fletcher Allen Health Care; Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center; Edward F Chan, MD, Clinical Assistant Professor, Department of Dermatology, University of Pennsylvania School of Medicine; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center Author and Editor Disclosure Synonyms and related keywords: DPN, hyperpigmented papules, facial papules, seborrheic keratosis INTRODUCTIONBackgroundDermatosis papulosa nigra (DPN) is a benign cutaneous condition common among blacks. It is usually characterized by multiple, small, hyperpigmented, asymptomatic papules on the face of adult blacks. Histologically, DPN resembles seborrheic keratoses. The condition may be cosmetically undesirable to some patients. PathophysiologyThe pathophysiology of DPN is not known. The occasional positive family history may suggest a genetic propensity. FrequencyUnited StatesWhereas earlier studies revealed a 10% frequency in adult blacks, more recent data suggest a frequency of approximately 35% in this population. InternationalData pertaining to the international frequency of DPN are insufficient. Mortality/MorbidityDPN is not associated with any mortality or morbidity. RaceDPN affects up to 35% of the African American population. Blacks with a fair complexion have the lowest frequency of involvement. DPN also occurs among Asians, although the exact incidence is unknown. SexFemales are affected more frequently than males. AgeDPN usually begins in adolescence and is rare under the age of 7 years. The incidence of DPN, as well as the number and size of individual lesions, increases with age. CLINICALHistoryLesions usually begin during puberty. They tend to increase steadily in number and size as the individual ages. PhysicalDPN is characterized by multiple, firm, smooth, dark brown to black, flattened papules that measure 1-5 mm in diameter. Lesions occur mainly on the malar area of the face and the forehead, although they also may be found on the neck, upper back, and chest. A small percentage of patients have similar lesions on the upper trunk. Scaling, crusting, and ulceration do not occur. CausesDPN is likely to be genetically determined, with 40-54% of patients having a family history of involvement. DPN is believed to be caused by a nevoid developmental defect of the pilosebaceous follicle. Hairston et al have suggested that DPN should be classified within the group of epithelial nevi. DIFFERENTIALSNevi, Melanocytic Seborrheic Keratosis
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