SKINIPEDIA - Skin Diseases: Congenital Dermal Melanocytosis

Skin Diseases and Conditions: Congenital Dermal Melanocytosis (Mongolian Spot)

 

Author: Abdul-Ghani Kibbi, MD, Professor and Chair, Department of Dermatology, American University of Beirut Medical Center, Lebanon
Coauthor(s): Ruba Faik Bahhady, MD,, Senior Specialist, Department of Dermatology, American University of Beirut Medical Center; Zeina Tannous, MD, Consulting Staff, Department of Dermatology, Massachusetts General Hospital, Harvard Medical School; Mazen Kurban, MD, Staff Physician, Department of Dermatology, American University of Beirut Medical Center

Background

Mongolian spot refers to a macular blue-gray pigmentation usually on the sacral area of healthy infants. Mongolian spot is usually present at birth or appears within the first weeks of life. Mongolian spot typically disappears spontaneously within 4 years but can persist for life.

Pathophysiology

Mongolian spot is a congenital, developmental condition exclusively involving the skin. Mongolian spot results from entrapment of melanocytes in the dermis during their migration from the neural crest into the epidermis. This migration is regulated by exogenous peptide growth factors that work by the activation of tyrosine kinase receptors. It is postulated that accumulated metabolites such as GM1 and heparan sulfate bind to this tyrosine kinase receptor and lead to severe neurologic manifestations and aberrant neural crest migration.

 

Frequency: United States

More than 90% of Native Americans, 80% of Asians, and 70% of Hispanics have Mongolian spots; less than 10% of whites have Mongolian spots.

International

The prevalence of Mongolian spots varies among different ethnic groups. This condition is most common among Asians. Mongolian spot has also been reported in 80% of East African children, in 46% of Hispanic children, and in 1-9% of white children.

Congenital Dermal Melanocytosis (Mongolian Spot)

Mortality/Morbidity

Mongolian spot is not associated with mortality or morbidity.

Race

Mongolian spots are observed in more than 90% of infants of the Mongoloid race (ie, East Asians, Indonesians, Polynesians, Micronesians, Amerindians, Eskimos).

Sex

No sex predilection is reported for Mongolian spot.

Age

Mongolian spot is usually present at birth, but it can also appear within the first weeks of the neonatal period.

Congenital Demal Menanocytosis - Mongolian Spot, Part II

Skin Diseases and Conditions

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