Noonan Syndrome: Obstacles in Making a Diagnosis - Abstract
Noonan syndrome (NS), is a common congenital genetic disorder due to defects in the PTPN11 gene or genes related to Ras/mitogen-activated protein kinase signaling pathway. Common features seen in individuals with NS include characteristic facial features, congenital heart defects, short stature, and developmental delay. Its presentation, however, can be variable with lack of clear genotype-phenotype correlation thus making the diagnosis of a child with NS challenging. In this case report we describe a late diagnosis of NS in a 14 year old male who presented with a normal height, but a predicted adult height discordant with his genetic potential. Furthermore an extensive genetics evaluation as an infant with karyotype and chromosomal microarray returned normal, which likely dismissed the presence of a genetic syndrome. This case highlights the obstacles that resulted in a delay in diagnosis and provides additional considerations for providers who have a clinical suspicion for NS. Early recognition is important for prompt initiation of counseling, monitoring and therapeutic interventions for comorbidities associated with NS.