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.

Clinical presentation

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

• L: lentigines (multiple)
• E: ECG conduction abnormalities
• O: ocular hypertelorism
• P: pulmonary stenosis
• A: abnormal genitals
• R: retardation of growth
• D: deafness (sensorineural)

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 .

Pathology

Genetics 

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

Associations

• congenital cardiac anomalies 

Complications

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

History and etymology

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

Siehe auch:

• Hypertelorismus
• Herzfehler
• Hypertrophe Kardiomyopathie
• pulmonic stenosis

und weiter:

• orbital hypertelorism