Skin melanocytic tumor
Topics to be merged
Mongolian spot
Author: Christopher S. Hale, M.D.
Topic Completed: 1 November 2014
Minor changes: 4 November 2020
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: Mongolian spot
Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Case reports | Treatment | Clinical images | Microscopic (histologic) description | Differential diagnosisCite this page: Hale CS. Mongolian spot. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skintumormelanocyticmongolianspot.html. Accessed July 24th, 2021.
Definition / general
- Ill defined area of blue discoloration, up to several centimeters and in lumbosacral region (eMedicine - Congenital Dermal Melanocytosis (Mongolian Spot), Wikipedia - Mongolian spot)
- May also occur at other sites
- See also Ito’s nevus
Terminology
- Also known as congenital dermal melanocytosis
- Related to "dermal melanocytoses" (nevus of Ito, nevus of Ota, Hori nevus)
- Although melanocytic, is NOT a true nevus
Epidemiology
- Congenital disorder, present at birth in most neonates from Asia, East-Africa or Turkey; also Native Americans
- Incidence of 60 - 70% in Iran, Nigeria and Taiwan (Pediatr Dermatol 2006;23:61, Niger J Med 2001;10:121, Chang Gung Med J 2007;30:220), usually regresses over several years, almost always by puberty, but may persist (Int J Dermatol 2005;44:43)
- Usually not present in children with blond hair (Turk J Pediatr 2006;48:232)
- Extensive Mongolian spots may be associated with inborn errors of metabolism (Pediatr Neurol 2006;34:143, Br J Dermatol 2003;148:1173)
Sites
- Usually sacral region
Case reports
- 1 year old boy with facial lesion near mandibular area (J Dermatol 2007;34:381)
- Four infants with darker pigmented Mongolian spot superimposed on another Mongolian spot (Pediatr Dermatol 2008;25:233)
Treatment
- Wait for regression
- Laser (Lasers Med Sci 2007;22:159)
Clinical images
Images hosted on other servers:
Mongolian spots
Microscopic (histologic) description
- Normal at low power
- High power shows occasional deep dendritic melanocytes, with melanin granules dissecting bundles of dermal collagen
- No associated melanophages
Differential diagnosis
- Bruises from child abuse
