Cardiac anomalies including pulmonary stenosis and hypertrophic cardiomyopathy were most prevalent (87.2%), and the prevalence of hypertrophic cardiomyopathy was greater in patients without PTPN11 mutations than in those with PTPN11 mutations.
Genotype-phenotype correlation analyses of previously reported NS patients harboring RIT1, PTPN11, SOS1, RAF1, and KRAS revealed that hypertrophic cardiomyopathy (56 %) was more frequent in patients harboring a RIT1 mutation than in patients harboring PTPN11 (9 %) and SOS1 mutations (10 %).
Implantable cardioverter defibrillator for progressive hypertrophic cardiomyopathy in a patient with LEOPARD syndrome and a novel PTPN11 mutation Gln510His.
In our total cohort, patients with NS and a PTPN11 mutation presented significantly higher prevalence of short stature (p = 0.03) and pulmonary valve stenosis (p = 0.01), and lower prevalence of hypertrophic cardiomyopathy (p = 0.01).
We describe the "LEOPARD syndrome (LS) phenotype" associated with the Gln510Glu mutation of the PTPN11 gene in two patients presenting with rapidly progressive severe biventricular obstructive hypertrophic cardiomyopathy and structural abnormalities of the mitral valve, facial anomalies, café-au-lait spots and multiple lentigines.
PTPN11 missense mutations cause approximately 50% of Noonan syndrome, an autosomal dominant disorder presenting with various congenital heart defects, most commonly valvar pulmonary stenosis, and hypertrophic cardiomyopathy.
Phenotypic evaluation in LS patients suggests that a hypertrophic cardiomyopathy rather than an electrocardiographic conduction abnormality is characteristic of PTPN11 mutation positive patients.
Six of eight subjects with PTPN11/SHP2 mutations had pulmonary valve stenosis while no mutations were identified in those subjects (N = 4) with hypertrophic cardiomyopathy.
Genotype-phenotype analysis revealed that pulmonic stenosis was more prevalent among the group of subjects with NS who had PTPN11 mutations than it was in the group without them (70.6% vs. 46.2%; P<.01), whereas hypertrophic cardiomyopathy was less prevalent among those with PTPN11 mutations (5.9% vs. 26.2%; P<.005).