Disease name

LEOPARD 증후군
 LEOPARD syndrome

Marker gene

Gene symbol Chromosome location Protein name
PTPN11 12q24.13 Tyrosine-protein phosphatase non-receptor type 11
RAF1 3p25.2 RAF proto-oncogene serine/threonine-protein kinase
BRAF 7q34 Serine/threonine-protein kinase B-raf

Prevalence

<1 / 1 000 000

Inheritance

상염색체 우성

Age of onset

소아기

ICD 10 code

Q87.8

MIM number

15110
611554
613707

Synonym

Cardiomyopathic lentiginosis
Familial multiple lentigines syndrome

Summary

LEOPARD syndrome (LS) is a rare multiple congenital anomalies condition, mainly characterized by skin, facial and cardiac anomalies. LEOPARD is an acronym for the major features of this disorder, including multiple Lentigines, ECG conduction abnormalities, Ocular hypertelorism, Pulmonic stenosis, Abnormal genitalia, Retardation of growth, and sensorineural Deafness. About 200 patients have been reported worldwide, but the real incidence of LS has not been assessed. Facial dysmorphism includes ocular hypertelorism, palpebral ptosis and low-set ears. Stature is usually below the 25th centile. Cardiac defects, in particular hypertrophic cardiomyopathy (mostly involving the left ventricle), and ECG anomalies are common. The lentigines may be congenital, although they more frequently manifest by the age of 4-5 years and increase throughout puberty. Additional common features are café-au-lait spots (CLS), chest anomalies, cryptorchidism, delayed puberty, hypotonia, mild developmental delay, sensorineural deafness and learning difficulties. In about 85% of the cases, a heterozygous missense mutation is detected in exons 7, 12 or 13 of the PTPN11 gene. Recently, missense mutations in the RAF1 gene have been found in two out of six PTPN11-negative LS patients. Mutation analysis can be carried out on blood, chorionic villi and amniotic fluid samples. LS shows a large overlap with Noonan syndrome and, during childhood, Neurofibromatosis type 1-Noonan syndrome (see these terms). Diagnostic clues for LS are multiple lentigines and CLS, hypertrophic cardiomyopathy and deafness. Mutation-based differential diagnosis in patients with borderline clinical manifestations is warranted. LS is an autosomal dominant condition, with full penetrance and variable expressivity. If one parent is affected, the recurrence risk is 50%. LS should be suspected in foetuses with severe cardiac hypertrophy and prenatal DNA testing may be performed. Clinical management should address growth and motor development and congenital anomalies, in particular cardiac defects that should be monitored annually. Hypertrophic cardiomyopathy needs careful risk assessment and prophylaxis to prevent sudden death in patients at risk. Hearing should be evaluated annually until adulthood. With the exception of ventricular hypertrophy, adults with LS do not require special medical care and the long-term prognosis is favourable.