PTPN11 Mutation Associated with Aortic Dilation and Hypertrophic Cardiomyopathy in a Pediatric Patient with Noonan Syndrome

Noonan syndrome is an autosomal dominant disease that manifests a wide variety of clinical characteristics. The syndrome is also associated with some cardiac defects. Half of all Noonan syndrome cases are caused by mutations in the PTPN11 gene, but only limited data are available regarding aortic involvement in these cases. No reports exist regarding PTPN11 mutations in association with both aortic dilation and hypertrophic cardiomyopathy. We describe an 8-year-old girl who had Noonan syndrome involving a PTPN11 mutation, hypertrophic cardiomyopathy, main pulmonary artery dilation, and aortic root dilation. To our knowledge, this is the first case in which all three of these cardiovascular features have been observed in a single patient with Noonan syndrome.