Mongolian spot

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Mongolian spot

Wikipedia

• Mongoloid spot, mongoloid spot

Mongolian spot (plural Mongolian spots)

1. A benign, flat, congenital, usually blue to blue-black birthmark on the lower back with wavy borders and irregular shape, prevalent among East Asians, South-East Asians, Polynesians, Native Americans, East Africans, and the Turkish people. It normally disappears three to five years after birth and almost always by puberty.
   • 1995, Theresa Overfield, Biological Variation in Health and Illness: Race, Age, and Sex Differences‎, page 13:

     Mongolian spots are produced by melanocyte leftovers that do not migrate into the epidermis; they remain deeper than usual in the lumbar-sacral region, resulting in blue coloration of the skin. Mongolian spots occur mainly on the buttocks and lower back, and occasionally on the abdomen, thighs, and arms. They occur in 90 percent of Blacks, 80 percent of Orientals and Native Americans, and 9 percent of Whites.

   • 2004, Adapted from Walter W. Tunnessen, Daniel P. Krowchuk, Chapter 46: Pediatric Dermatology, Michael Crocetti, Michael A. Barone, Frank A. Oski (editors), Oski's Essential Pediatrics, page 135,

     Mongolian spot is an unfortunate name for this common, benign skin discoloration. Present at birth, mongolian spots are blue-gray or blue-green and represent areas of dermal melanocytosis.

   • 2008, Margaret M. Andrews, “Chapter 3: Cultural Competence in the Health History and Physical Examination”, in Margaret M. Andrews, Joyceen S. Boyle, editors, Transcultural Concepts in Nursing Care, page 51:

     Mongolian spots consist of embryonic pigment that has been left behind in the epidermal layer during fetal development. […] Mongolian spots are a normal variation in children of African, Asian, or Latin descent.

• (blue or blue black birthmark on the lower back): congenital dermal melanocytosis, dermal melanocytosis, Mongoloid spot