Growth Hormone Treatment for Patients with Noonan Syndrome

Noonan syndrome (NS) is a genetic disorder, which can present clinically with a variable phenotype. Proportional post natal short stature is a common manifestation of NS, with the majority of affected patients having an adult height below the third percentile. Some investigators have reported minor abnormalities in GH secretion and/or action, suggesting that recombinant growth hormone (rhGH) therapy may be useful for the treatment of their short stature. Our review of the literature regarding rhGH therapy in children with NS indicates that this therapy improves height velocity, but relatively few controlled clinical trials reporting adult height are available. rhGH treatment does not appear to be associated with adverse effects in these patients, but data on the possible development of malignancy during treatment are somewhat limited. Therefore, we believe that there is a need for large controlled clinical trials in patients with this condition, in order to accurately assess the effects of rhGH therapy over adult height.