Noonan Syndrome

Noonan syndrome is a genetic condition inherited by an autosomally dominant manner, characterised by congenital heart disease, short stature, abnormal facies and the somatic feature of Turner's syndrome, but a normal karyotype. Noonan syndrome affects approximately 1 in 1500 live births.
Congenital heart disease occurs in 35-50% of patients diagnosed with noonan syndrome. The most common cardiac lesions are pulmonary stenosis and hypertrophic cardiomyopathy. The frequency of renal anomalies in noonan syndrome is lower than that seen in Turner syndrome. However, splenomegaly with or without hepatomegaly occurs commonly. Ocular manifestations, coagulation factor deficiencies and abnormal bleeding and genital tract malformation are other features of this syndrome. If both parents had only possible or no signs of noonan syndrome, subsequent to the birth of the first child with noonan syndrome in a family, an empiric recurrence risk of 5% is predicted.
Successful treatment of short stature with growth hormone are reported. We report a 7-year old boy with noonan syndrome who presented with short stature, abnormal facies, congenital heart disease and bilateral undescended testis.