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Neurocutaneous melanocytosis

Disease definition

Neurocutaneous melanocytosis (NCM) is a rare congenital neurological disorder characterized by abnormal aggregations of nevomelanocytes within the central nervous system (leptomeningeal melanocytosis) associated with large or giant congenital melanocytic nevi (CMN; see this term). NCM can be asymptomatic or present as variably severe and progressive neurological impairment, sometimes resulting in death.


Classification level: Disorder
  • Synonym(s):
    • NCM
    • Neurocutaneous melanosis
  • Prevalence: 1-9 / 100 000
  • Inheritance: Not applicable 
  • Age of onset: Childhood
  • ICD-10: D22.3  D22.4  D22.5  D22.6  D22.7
  • OMIM: 249400
  • UMLS: C0544862
  • MeSH: C537387
  • GARD: 7186
  • MedDRA: -

Detailed information


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