Noonan syndrome with multiple lentigines

Noonan syndrome with multiple lentigines, previously known as LEOPARD syndrome (LS), is a rare autosomal dominant RASopathy that has many similarities to Noonan syndrome.

Despite a change in formal name, the 'LEOPARD' acronym is still useful to summarise the clinical features:

Importantly, this acronym does not include the other craniofacial anomalies (in addition to hypertelorism) which are identical to those of Noonan syndrome and present in nearly all patients 5

Thought to result from a mutation in the PTPN11 (protein tyrosinephosphatase nonreceptor type 11) gene located on chromosome 12q24.1 2, which results in increased signalling of the Ras/MAPK pathway. Thus, the disorder is classified as a RASopathy 5.

One concerning potential complication is the development of hypertrophic cardiomyopathy (HCM) (often in infancy) related to congenital cardiac defects.

Originally described by R J Gorlin and his colleagues in 1969 1.

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Article information

rID: 13885
Section: Syndromes
Synonyms or Alternate Spellings:
  • LEOPARD syndrome (LS)
  • Gorlin type II syndrome
  • Lentiginosis profusa syndrome
  • LEOPARD syndrome

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